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[PATCH 00/16] Thunderbolt networking

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  [PATCH 00/16] Thunderbolt networking Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 03/16] thunderbolt: Move enum tb_cfg_pkg_type to thunderbolt.h Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 05/16] thunderbolt: Move tb_switch_phy_port_from_link() to thunderbolt.h Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 14/16] thunderbolt: Add function to retrieve DMA device for the ring Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 09/16] thunderbolt: Export ring handling functions to modules Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 12/16] thunderbolt: Use spinlock in NHI serialization Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 15/16] thunderbolt: Allocate ring HopID automatically if requested Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 10/16] thunderbolt: Move ring descriptor flags to thunderbolt.h Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 13/16] thunderbolt: Add polling mode for rings Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 02/16] thunderbolt: Add support for XDomain properties Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 08/16] thunderbolt: Add support for frame mode Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 11/16] thunderbolt: Use spinlock in ring serialization Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    [PATCH 07/16] thunderbolt: Configure interrupt throttling for all interrupts Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-18 17:40 +0200
    Re: [PATCH 16/16] thunderbolt: Add support for networking over  Thunderbolt cable Andrew Lunn <andrew@lunn.ch> - 2017-09-19 01:30 +0200
      Re: [PATCH 16/16] thunderbolt: Add support for networking over  Thunderbolt cable Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-19 09:20 +0200
    Re: [PATCH 06/16] thunderbolt: Add support for XDomain discovery  protocol Mika Westerberg <mika.westerberg@linux.intel.com> - 2017-09-19 09:50 +0200

#1734230 — [PATCH 00/16] Thunderbolt networking

Hi all,

In addition of tunneling PCIe, Display Port and USB traffic, Thunderbolt
allows connecting two hosts (domains) over a Thunderbolt cable. It is
possible to tunnel arbitrary data packets over such connection using
high-speed DMA rings available in the Thunderbolt host controller.

In order to discover Thunderbolt services the other host supports, there is
a software protocol running on top of the automatically configured control
channel (ring 0). This protocol is called XDomain discovery protocol and it
uses XDomain properties to describe the host (domain) and the services it
supports.

Once both sides have agreed what services are supported they can enable
high-speed DMA rings to transfer data over the cable.

This series adds support for the XDomain protocol so that we expose each
remote connection as Thunderbolt XDomain device and each service as
Thunderbolt service device. On top of that we create an API that allows
writing drivers for these services and finally we provide an example
Thunderbolt service driver that creates virtual ethernet inferface that
allows tunneling networking packets over Thunderbolt cable. The API could
be used for creating other Thunderbolt services, such as tunneling SCSI for
example.

The XDomain protocol and networking support is also available in macOS and
Windows so this makes it possible to connect Linux to macOS and Windows as
well.

The patches are based on previous Thunderbolt networking patch series by
Amir Levy and Michael Jamet, that can be found here:

  https://lwn.net/Articles/705998/

The main difference to that patch series is that we have the XDomain
protocol running in the kernel now so there is no need for a separate
userspace daemon.

Note this does not affect the existing functionality, so security levels
and NVM firmware upgrade continue to work as before (with the small
exception that now sysfs also shows the XDomain connections and services in
addition to normal Thunderbolt devices).

In case someone wants to try this out, patch [16/16] adds documentation
how the networking driver can be used. In short, if you connect Linux to
a macOS or Windows, everything is done automatically (as those systems
have the networking service enabled by default). For Linux to Linux
connection one host needs to load the networking driver first (so that
the other side can locate the networking service and load the
corresponding driver).

Amir Levy (1):
  thunderbolt: Add support for networking over Thunderbolt cable

Mika Westerberg (15):
  byteorder: Move {cpu_to_be32,be32_to_cpu}_array() from Thunderbolt to core
  thunderbolt: Add support for XDomain properties
  thunderbolt: Move enum tb_cfg_pkg_type to thunderbolt.h
  thunderbolt: Move thunderbolt domain structure to thunderbolt.h
  thunderbolt: Move tb_switch_phy_port_from_link() to thunderbolt.h
  thunderbolt: Add support for XDomain discovery protocol
  thunderbolt: Configure interrupt throttling for all interrupts
  thunderbolt: Add support for frame mode
  thunderbolt: Export ring handling functions to modules
  thunderbolt: Move ring descriptor flags to thunderbolt.h
  thunderbolt: Use spinlock in ring serialization
  thunderbolt: Use spinlock in NHI serialization
  thunderbolt: Add polling mode for rings
  thunderbolt: Add function to retrieve DMA device for the ring
  thunderbolt: Allocate ring HopID automatically if requested

 Documentation/ABI/testing/sysfs-bus-thunderbolt |   48 +
 Documentation/admin-guide/thunderbolt.rst       |   24 +
 drivers/thunderbolt/Kconfig                     |   12 +
 drivers/thunderbolt/Makefile                    |    5 +-
 drivers/thunderbolt/ctl.c                       |   46 +-
 drivers/thunderbolt/ctl.h                       |    3 +-
 drivers/thunderbolt/domain.c                    |  197 ++-
 drivers/thunderbolt/icm.c                       |  218 +++-
 drivers/thunderbolt/net.c                       | 1392 ++++++++++++++++++++
 drivers/thunderbolt/nhi.c                       |  409 ++++--
 drivers/thunderbolt/nhi.h                       |  141 +-
 drivers/thunderbolt/nhi_regs.h                  |   11 +-
 drivers/thunderbolt/property.c                  |  670 ++++++++++
 drivers/thunderbolt/switch.c                    |    7 +-
 drivers/thunderbolt/tb.h                        |   88 +-
 drivers/thunderbolt/tb_msgs.h                   |  140 +-
 drivers/thunderbolt/xdomain.c                   | 1576 +++++++++++++++++++++++
 include/linux/byteorder/generic.h               |   16 +
 include/linux/mod_devicetable.h                 |   26 +
 include/linux/thunderbolt.h                     |  598 +++++++++
 scripts/mod/devicetable-offsets.c               |    7 +
 scripts/mod/file2alias.c                        |   25 +
 22 files changed, 5310 insertions(+), 349 deletions(-)
 create mode 100644 drivers/thunderbolt/net.c
 create mode 100644 drivers/thunderbolt/property.c
 create mode 100644 drivers/thunderbolt/xdomain.c
 create mode 100644 include/linux/thunderbolt.h

-- 
2.13.5

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#1734231 — [PATCH 03/16] thunderbolt: Move enum tb_cfg_pkg_type to thunderbolt.h

These will be needed by Thunderbolt services when sending and receiving
XDomain control messages.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 drivers/thunderbolt/ctl.h     |  1 +
 drivers/thunderbolt/tb_msgs.h | 17 -----------------
 include/linux/thunderbolt.h   | 17 +++++++++++++++++
 3 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/drivers/thunderbolt/ctl.h b/drivers/thunderbolt/ctl.h
index 36fd28b1c1c5..d0f21e1e0b8b 100644
--- a/drivers/thunderbolt/ctl.h
+++ b/drivers/thunderbolt/ctl.h
@@ -8,6 +8,7 @@
 #define _TB_CFG
 
 #include <linux/kref.h>
+#include <linux/thunderbolt.h>
 
 #include "nhi.h"
 #include "tb_msgs.h"
diff --git a/drivers/thunderbolt/tb_msgs.h b/drivers/thunderbolt/tb_msgs.h
index de6441e4a060..fe3039b05da6 100644
--- a/drivers/thunderbolt/tb_msgs.h
+++ b/drivers/thunderbolt/tb_msgs.h
@@ -15,23 +15,6 @@
 #include <linux/types.h>
 #include <linux/uuid.h>
 
-enum tb_cfg_pkg_type {
-	TB_CFG_PKG_READ = 1,
-	TB_CFG_PKG_WRITE = 2,
-	TB_CFG_PKG_ERROR = 3,
-	TB_CFG_PKG_NOTIFY_ACK = 4,
-	TB_CFG_PKG_EVENT = 5,
-	TB_CFG_PKG_XDOMAIN_REQ = 6,
-	TB_CFG_PKG_XDOMAIN_RESP = 7,
-	TB_CFG_PKG_OVERRIDE = 8,
-	TB_CFG_PKG_RESET = 9,
-	TB_CFG_PKG_ICM_EVENT = 10,
-	TB_CFG_PKG_ICM_CMD = 11,
-	TB_CFG_PKG_ICM_RESP = 12,
-	TB_CFG_PKG_PREPARE_TO_SLEEP = 0xd,
-
-};
-
 enum tb_cfg_space {
 	TB_CFG_HOPS = 0,
 	TB_CFG_PORT = 1,
diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
index 5673a4b4becb..0b22b64dacba 100644
--- a/include/linux/thunderbolt.h
+++ b/include/linux/thunderbolt.h
@@ -1,6 +1,7 @@
 /*
  * Thunderbolt service API
  *
+ * Copyright (C) 2014 Andreas Noever <andreas.noever@gmail.com>
  * Copyright (C) 2017, Intel Corporation
  * Authors: Michael Jamet <michael.jamet@intel.com>
  *          Mika Westerberg <mika.westerberg@linux.intel.com>
@@ -16,6 +17,22 @@
 #include <linux/list.h>
 #include <linux/uuid.h>
 
+enum tb_cfg_pkg_type {
+	TB_CFG_PKG_READ = 1,
+	TB_CFG_PKG_WRITE = 2,
+	TB_CFG_PKG_ERROR = 3,
+	TB_CFG_PKG_NOTIFY_ACK = 4,
+	TB_CFG_PKG_EVENT = 5,
+	TB_CFG_PKG_XDOMAIN_REQ = 6,
+	TB_CFG_PKG_XDOMAIN_RESP = 7,
+	TB_CFG_PKG_OVERRIDE = 8,
+	TB_CFG_PKG_RESET = 9,
+	TB_CFG_PKG_ICM_EVENT = 10,
+	TB_CFG_PKG_ICM_CMD = 11,
+	TB_CFG_PKG_ICM_RESP = 12,
+	TB_CFG_PKG_PREPARE_TO_SLEEP = 0xd,
+};
+
 /**
  * struct tb_property_dir - XDomain property directory
  * @uuid: Directory UUID or %NULL if root directory
-- 
2.13.5

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#1734232 — [PATCH 05/16] thunderbolt: Move tb_switch_phy_port_from_link() to thunderbolt.h

A Thunderbolt service might need to find the physical port from a link
the cable is connected to. For instance networking driver uses this
information to generate MAC address according the Apple ThunderboltIP
protocol.

Move this function to thunderbolt.h and rename it to
tb_phy_port_from_link() to reflect the fact that it does not take switch
as parameter.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 drivers/thunderbolt/icm.c   | 2 +-
 drivers/thunderbolt/tb.h    | 7 -------
 include/linux/thunderbolt.h | 7 +++++++
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c
index 53250fc057e1..8c22b91ed040 100644
--- a/drivers/thunderbolt/icm.c
+++ b/drivers/thunderbolt/icm.c
@@ -89,7 +89,7 @@ static inline struct tb *icm_to_tb(struct icm *icm)
 
 static inline u8 phy_port_from_route(u64 route, u8 depth)
 {
-	return tb_switch_phy_port_from_link(route >> ((depth - 1) * 8));
+	return tb_phy_port_from_link(route >> ((depth - 1) * 8));
 }
 
 static inline u8 dual_link_from_link(u8 link)
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index 2fefe76621ca..ea21d927bd09 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -40,8 +40,6 @@ struct tb_switch_nvm {
 };
 
 #define TB_SWITCH_KEY_SIZE		32
-/* Each physical port contains 2 links on modern controllers */
-#define TB_SWITCH_LINKS_PER_PHY_PORT	2
 
 /**
  * struct tb_switch - a thunderbolt switch
@@ -367,11 +365,6 @@ struct tb_switch *tb_switch_find_by_link_depth(struct tb *tb, u8 link,
 					       u8 depth);
 struct tb_switch *tb_switch_find_by_uuid(struct tb *tb, const uuid_t *uuid);
 
-static inline unsigned int tb_switch_phy_port_from_link(unsigned int link)
-{
-	return (link - 1) / TB_SWITCH_LINKS_PER_PHY_PORT;
-}
-
 static inline void tb_switch_put(struct tb_switch *sw)
 {
 	put_device(&sw->dev);
diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
index 89dbb0c20f07..4011d6537a8c 100644
--- a/include/linux/thunderbolt.h
+++ b/include/linux/thunderbolt.h
@@ -78,6 +78,13 @@ struct tb {
 
 extern struct bus_type tb_bus_type;
 
+#define TB_LINKS_PER_PHY_PORT	2
+
+static inline unsigned int tb_phy_port_from_link(unsigned int link)
+{
+	return (link - 1) / TB_LINKS_PER_PHY_PORT;
+}
+
 /**
  * struct tb_property_dir - XDomain property directory
  * @uuid: Directory UUID or %NULL if root directory
-- 
2.13.5

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#1734233 — [PATCH 14/16] thunderbolt: Add function to retrieve DMA device for the ring

This is needed when Thunderbolt service drivers need to DMA map memory
before it is passed down to the ring.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 include/linux/thunderbolt.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
index 9a63210d5084..d479a9e508cd 100644
--- a/include/linux/thunderbolt.h
+++ b/include/linux/thunderbolt.h
@@ -19,6 +19,7 @@
 #include <linux/list.h>
 #include <linux/mutex.h>
 #include <linux/mod_devicetable.h>
+#include <linux/pci.h>
 #include <linux/uuid.h>
 #include <linux/workqueue.h>
 
@@ -582,4 +583,16 @@ static inline int tb_ring_tx(struct tb_ring *ring, struct ring_frame *frame)
 struct ring_frame *tb_ring_poll(struct tb_ring *ring);
 void tb_ring_poll_complete(struct tb_ring *ring);
 
+/**
+ * tb_ring_dma_device() - Return device used for DMA mapping
+ * @ring: Ring whose DMA device is retrieved
+ *
+ * Use this function when you are mapping DMA for buffers that are
+ * passed to the ring for sending/receiving.
+ */
+static inline struct device *tb_ring_dma_device(struct tb_ring *ring)
+{
+	return &ring->nhi->pdev->dev;
+}
+
 #endif /* THUNDERBOLT_H_ */
-- 
2.13.5

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#1734234 — [PATCH 09/16] thunderbolt: Export ring handling functions to modules

These are used by Thunderbolt services to send and receive frames over
the high-speed DMA rings.

We also put the functions to tb_ namespace to make sure we do not
collide with others and add missing kernel-doc comments for the exported
functions.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 drivers/thunderbolt/ctl.c   |  20 +++---
 drivers/thunderbolt/nhi.c   |  62 +++++++++++------
 drivers/thunderbolt/nhi.h   | 147 +----------------------------------------
 include/linux/thunderbolt.h | 158 ++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 211 insertions(+), 176 deletions(-)

diff --git a/drivers/thunderbolt/ctl.c b/drivers/thunderbolt/ctl.c
index 05400b77dcd7..dd10789e1dbb 100644
--- a/drivers/thunderbolt/ctl.c
+++ b/drivers/thunderbolt/ctl.c
@@ -359,7 +359,7 @@ static int tb_ctl_tx(struct tb_ctl *ctl, const void *data, size_t len,
 	cpu_to_be32_array(pkg->buffer, data, len / 4);
 	*(__be32 *) (pkg->buffer + len) = tb_crc(pkg->buffer, len);
 
-	res = ring_tx(ctl->tx, &pkg->frame);
+	res = tb_ring_tx(ctl->tx, &pkg->frame);
 	if (res) /* ring is stopped */
 		tb_ctl_pkg_free(pkg);
 	return res;
@@ -376,7 +376,7 @@ static bool tb_ctl_handle_event(struct tb_ctl *ctl, enum tb_cfg_pkg_type type,
 
 static void tb_ctl_rx_submit(struct ctl_pkg *pkg)
 {
-	ring_rx(pkg->ctl->rx, &pkg->frame); /*
+	tb_ring_rx(pkg->ctl->rx, &pkg->frame); /*
 					     * We ignore failures during stop.
 					     * All rx packets are referenced
 					     * from ctl->rx_packets, so we do
@@ -614,11 +614,11 @@ struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, event_cb cb, void *cb_data)
 	if (!ctl->frame_pool)
 		goto err;
 
-	ctl->tx = ring_alloc_tx(nhi, 0, 10, RING_FLAG_NO_SUSPEND);
+	ctl->tx = tb_ring_alloc_tx(nhi, 0, 10, RING_FLAG_NO_SUSPEND);
 	if (!ctl->tx)
 		goto err;
 
-	ctl->rx = ring_alloc_rx(nhi, 0, 10, RING_FLAG_NO_SUSPEND, 0xffff,
+	ctl->rx = tb_ring_alloc_rx(nhi, 0, 10, RING_FLAG_NO_SUSPEND, 0xffff,
 				0xffff);
 	if (!ctl->rx)
 		goto err;
@@ -652,9 +652,9 @@ void tb_ctl_free(struct tb_ctl *ctl)
 		return;
 
 	if (ctl->rx)
-		ring_free(ctl->rx);
+		tb_ring_free(ctl->rx);
 	if (ctl->tx)
-		ring_free(ctl->tx);
+		tb_ring_free(ctl->tx);
 
 	/* free RX packets */
 	for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++)
@@ -673,8 +673,8 @@ void tb_ctl_start(struct tb_ctl *ctl)
 {
 	int i;
 	tb_ctl_info(ctl, "control channel starting...\n");
-	ring_start(ctl->tx); /* is used to ack hotplug packets, start first */
-	ring_start(ctl->rx);
+	tb_ring_start(ctl->tx); /* is used to ack hotplug packets, start first */
+	tb_ring_start(ctl->rx);
 	for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++)
 		tb_ctl_rx_submit(ctl->rx_packets[i]);
 
@@ -695,8 +695,8 @@ void tb_ctl_stop(struct tb_ctl *ctl)
 	ctl->running = false;
 	mutex_unlock(&ctl->request_queue_lock);
 
-	ring_stop(ctl->rx);
-	ring_stop(ctl->tx);
+	tb_ring_stop(ctl->rx);
+	tb_ring_stop(ctl->tx);
 
 	if (!list_empty(&ctl->request_queue))
 		tb_ctl_WARN(ctl, "dangling request in request_queue\n");
diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index cde8b6d46147..4704ccd20c84 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -253,7 +253,7 @@ static void ring_work(struct work_struct *work)
 	}
 }
 
-int __ring_enqueue(struct tb_ring *ring, struct ring_frame *frame)
+int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame)
 {
 	int ret = 0;
 	mutex_lock(&ring->lock);
@@ -266,6 +266,7 @@ int __ring_enqueue(struct tb_ring *ring, struct ring_frame *frame)
 	mutex_unlock(&ring->lock);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(__tb_ring_enqueue);
 
 static irqreturn_t ring_msix(int irq, void *data)
 {
@@ -309,9 +310,9 @@ static void ring_release_msix(struct tb_ring *ring)
 	ring->irq = 0;
 }
 
-static struct tb_ring *ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
-				  bool transmit, unsigned int flags,
-				  u16 sof_mask, u16 eof_mask)
+static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
+				     bool transmit, unsigned int flags,
+				     u16 sof_mask, u16 eof_mask)
 {
 	struct tb_ring *ring = NULL;
 	dev_info(&nhi->pdev->dev, "allocating %s ring %d of size %d\n",
@@ -377,24 +378,42 @@ static struct tb_ring *ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 	return NULL;
 }
 
-struct tb_ring *ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
-			      unsigned int flags)
+/**
+ * tb_ring_alloc_tx() - Allocate DMA ring for transmit
+ * @nhi: Pointer to the NHI the ring is to be allocated
+ * @hop: HopID (ring) to allocate
+ * @size: Number of entries in the ring
+ * @flags: Flags for the ring
+ */
+struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
+				 unsigned int flags)
 {
-	return ring_alloc(nhi, hop, size, true, flags, 0, 0);
+	return tb_ring_alloc(nhi, hop, size, true, flags, 0, 0);
 }
+EXPORT_SYMBOL_GPL(tb_ring_alloc_tx);
 
-struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
-			      unsigned int flags, u16 sof_mask, u16 eof_mask)
+/**
+ * tb_ring_alloc_rx() - Allocate DMA ring for receive
+ * @nhi: Pointer to the NHI the ring is to be allocated
+ * @hop: HopID (ring) to allocate
+ * @size: Number of entries in the ring
+ * @flags: Flags for the ring
+ * @sof_mask: Mask of PDF values that start a frame
+ * @eof_mask: Mask of PDF values that end a frame
+ */
+struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
+				 unsigned int flags, u16 sof_mask, u16 eof_mask)
 {
-	return ring_alloc(nhi, hop, size, false, flags, sof_mask, eof_mask);
+	return tb_ring_alloc(nhi, hop, size, false, flags, sof_mask, eof_mask);
 }
+EXPORT_SYMBOL_GPL(tb_ring_alloc_rx);
 
 /**
- * ring_start() - enable a ring
+ * tb_ring_start() - enable a ring
  *
- * Must not be invoked in parallel with ring_stop().
+ * Must not be invoked in parallel with tb_ring_stop().
  */
-void ring_start(struct tb_ring *ring)
+void tb_ring_start(struct tb_ring *ring)
 {
 	u16 frame_size;
 	u32 flags;
@@ -450,21 +469,22 @@ void ring_start(struct tb_ring *ring)
 	mutex_unlock(&ring->lock);
 	mutex_unlock(&ring->nhi->lock);
 }
-
+EXPORT_SYMBOL_GPL(tb_ring_start);
 
 /**
- * ring_stop() - shutdown a ring
+ * tb_ring_stop() - shutdown a ring
  *
  * Must not be invoked from a callback.
  *
- * This method will disable the ring. Further calls to ring_tx/ring_rx will
- * return -ESHUTDOWN until ring_stop has been called.
+ * This method will disable the ring. Further calls to
+ * tb_ring_tx/tb_ring_rx will return -ESHUTDOWN until ring_stop has been
+ * called.
  *
  * All enqueued frames will be canceled and their callbacks will be executed
  * with frame->canceled set to true (on the callback thread). This method
  * returns only after all callback invocations have finished.
  */
-void ring_stop(struct tb_ring *ring)
+void tb_ring_stop(struct tb_ring *ring)
 {
 	mutex_lock(&ring->nhi->lock);
 	mutex_lock(&ring->lock);
@@ -497,9 +517,10 @@ void ring_stop(struct tb_ring *ring)
 	schedule_work(&ring->work);
 	flush_work(&ring->work);
 }
+EXPORT_SYMBOL_GPL(tb_ring_stop);
 
 /*
- * ring_free() - free ring
+ * tb_ring_free() - free ring
  *
  * When this method returns all invocations of ring->callback will have
  * finished.
@@ -508,7 +529,7 @@ void ring_stop(struct tb_ring *ring)
  *
  * Must NOT be called from ring_frame->callback!
  */
-void ring_free(struct tb_ring *ring)
+void tb_ring_free(struct tb_ring *ring)
 {
 	mutex_lock(&ring->nhi->lock);
 	/*
@@ -550,6 +571,7 @@ void ring_free(struct tb_ring *ring)
 	mutex_destroy(&ring->lock);
 	kfree(ring);
 }
+EXPORT_SYMBOL_GPL(tb_ring_free);
 
 /**
  * nhi_mailbox_cmd() - Send a command through NHI mailbox
diff --git a/drivers/thunderbolt/nhi.h b/drivers/thunderbolt/nhi.h
index 4503ddbeccb3..771d09ca5dc5 100644
--- a/drivers/thunderbolt/nhi.h
+++ b/drivers/thunderbolt/nhi.h
@@ -7,152 +7,7 @@
 #ifndef DSL3510_H_
 #define DSL3510_H_
 
-#include <linux/idr.h>
-#include <linux/mutex.h>
-#include <linux/workqueue.h>
-
-/**
- * struct tb_nhi - thunderbolt native host interface
- * @lock: Must be held during ring creation/destruction. Is acquired by
- *	  interrupt_work when dispatching interrupts to individual rings.
- * @pdev: Pointer to the PCI device
- * @iobase: MMIO space of the NHI
- * @tx_rings: All Tx rings available on this host controller
- * @rx_rings: All Rx rings available on this host controller
- * @msix_ida: Used to allocate MSI-X vectors for rings
- * @going_away: The host controller device is about to disappear so when
- *		this flag is set, avoid touching the hardware anymore.
- * @interrupt_work: Work scheduled to handle ring interrupt when no
- *		    MSI-X is used.
- * @hop_count: Number of rings (end point hops) supported by NHI.
- */
-struct tb_nhi {
-	struct mutex lock;
-	struct pci_dev *pdev;
-	void __iomem *iobase;
-	struct tb_ring **tx_rings;
-	struct tb_ring **rx_rings;
-	struct ida msix_ida;
-	bool going_away;
-	struct work_struct interrupt_work;
-	u32 hop_count;
-};
-
-/**
- * struct tb_ring - thunderbolt TX or RX ring associated with a NHI
- * @lock: Lock serializing actions to this ring. Must be acquired after
- *	  nhi->lock.
- * @nhi: Pointer to the native host controller interface
- * @size: Size of the ring
- * @hop: Hop (DMA channel) associated with this ring
- * @head: Head of the ring (write next descriptor here)
- * @tail: Tail of the ring (complete next descriptor here)
- * @descriptors: Allocated descriptors for this ring
- * @queue: Queue holding frames to be transferred over this ring
- * @in_flight: Queue holding frames that are currently in flight
- * @work: Interrupt work structure
- * @is_tx: Is the ring Tx or Rx
- * @running: Is the ring running
- * @irq: MSI-X irq number if the ring uses MSI-X. %0 otherwise.
- * @vector: MSI-X vector number the ring uses (only set if @irq is > 0)
- * @flags: Ring specific flags
- * @sof_mask: Bit mask used to detect start of frame PDF
- * @eof_mask: Bit mask used to detect end of frame PDF
- */
-struct tb_ring {
-	struct mutex lock;
-	struct tb_nhi *nhi;
-	int size;
-	int hop;
-	int head;
-	int tail;
-	struct ring_desc *descriptors;
-	dma_addr_t descriptors_dma;
-	struct list_head queue;
-	struct list_head in_flight;
-	struct work_struct work;
-	bool is_tx:1;
-	bool running:1;
-	int irq;
-	u8 vector;
-	unsigned int flags;
-	u16 sof_mask;
-	u16 eof_mask;
-};
-
-/* Leave ring interrupt enabled on suspend */
-#define RING_FLAG_NO_SUSPEND	BIT(0)
-/* Configure the ring to be in frame mode */
-#define RING_FLAG_FRAME		BIT(1)
-/* Enable end-to-end flow control */
-#define RING_FLAG_E2E		BIT(2)
-
-struct ring_frame;
-typedef void (*ring_cb)(struct tb_ring*, struct ring_frame*, bool canceled);
-
-/**
- * struct ring_frame - for use with ring_rx/ring_tx
- */
-struct ring_frame {
-	dma_addr_t buffer_phy;
-	ring_cb callback;
-	struct list_head list;
-	u32 size:12; /* TX: in, RX: out*/
-	u32 flags:12; /* RX: out */
-	u32 eof:4; /* TX:in, RX: out */
-	u32 sof:4; /* TX:in, RX: out */
-};
-
-#define TB_FRAME_SIZE 0x100    /* minimum size for ring_rx */
-
-struct tb_ring *ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
-			      unsigned int flags);
-struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
-			      unsigned int flags, u16 sof_mask, u16 eof_mask);
-void ring_start(struct tb_ring *ring);
-void ring_stop(struct tb_ring *ring);
-void ring_free(struct tb_ring *ring);
-
-int __ring_enqueue(struct tb_ring *ring, struct ring_frame *frame);
-
-/**
- * ring_rx() - enqueue a frame on an RX ring
- *
- * frame->buffer, frame->buffer_phy and frame->callback have to be set. The
- * buffer must contain at least TB_FRAME_SIZE bytes.
- *
- * frame->callback will be invoked with frame->size, frame->flags, frame->eof,
- * frame->sof set once the frame has been received.
- *
- * If ring_stop is called after the packet has been enqueued frame->callback
- * will be called with canceled set to true.
- *
- * Return: Returns ESHUTDOWN if ring_stop has been called. Zero otherwise.
- */
-static inline int ring_rx(struct tb_ring *ring, struct ring_frame *frame)
-{
-	WARN_ON(ring->is_tx);
-	return __ring_enqueue(ring, frame);
-}
-
-/**
- * ring_tx() - enqueue a frame on an TX ring
- *
- * frame->buffer, frame->buffer_phy, frame->callback, frame->size, frame->eof
- * and frame->sof have to be set.
- *
- * frame->callback will be invoked with once the frame has been transmitted.
- *
- * If ring_stop is called after the packet has been enqueued frame->callback
- * will be called with canceled set to true.
- *
- * Return: Returns ESHUTDOWN if ring_stop has been called. Zero otherwise.
- */
-static inline int ring_tx(struct tb_ring *ring, struct ring_frame *frame)
-{
-	WARN_ON(!ring->is_tx);
-	return __ring_enqueue(ring, frame);
-}
+#include <linux/thunderbolt.h>
 
 enum nhi_fw_mode {
 	NHI_FW_SAFE_MODE,
diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
index 79abdaf1c296..1a376374c327 100644
--- a/include/linux/thunderbolt.h
+++ b/include/linux/thunderbolt.h
@@ -15,10 +15,12 @@
 #define THUNDERBOLT_H_
 
 #include <linux/device.h>
+#include <linux/idr.h>
 #include <linux/list.h>
 #include <linux/mutex.h>
 #include <linux/mod_devicetable.h>
 #include <linux/uuid.h>
+#include <linux/workqueue.h>
 
 enum tb_cfg_pkg_type {
 	TB_CFG_PKG_READ = 1,
@@ -397,4 +399,160 @@ static inline struct tb_xdomain *tb_service_parent(struct tb_service *svc)
 	return tb_to_xdomain(svc->dev.parent);
 }
 
+/**
+ * struct tb_nhi - thunderbolt native host interface
+ * @lock: Must be held during ring creation/destruction. Is acquired by
+ *	  interrupt_work when dispatching interrupts to individual rings.
+ * @pdev: Pointer to the PCI device
+ * @iobase: MMIO space of the NHI
+ * @tx_rings: All Tx rings available on this host controller
+ * @rx_rings: All Rx rings available on this host controller
+ * @msix_ida: Used to allocate MSI-X vectors for rings
+ * @going_away: The host controller device is about to disappear so when
+ *		this flag is set, avoid touching the hardware anymore.
+ * @interrupt_work: Work scheduled to handle ring interrupt when no
+ *		    MSI-X is used.
+ * @hop_count: Number of rings (end point hops) supported by NHI.
+ */
+struct tb_nhi {
+	struct mutex lock;
+	struct pci_dev *pdev;
+	void __iomem *iobase;
+	struct tb_ring **tx_rings;
+	struct tb_ring **rx_rings;
+	struct ida msix_ida;
+	bool going_away;
+	struct work_struct interrupt_work;
+	u32 hop_count;
+};
+
+/**
+ * struct tb_ring - thunderbolt TX or RX ring associated with a NHI
+ * @lock: Lock serializing actions to this ring. Must be acquired after
+ *	  nhi->lock.
+ * @nhi: Pointer to the native host controller interface
+ * @size: Size of the ring
+ * @hop: Hop (DMA channel) associated with this ring
+ * @head: Head of the ring (write next descriptor here)
+ * @tail: Tail of the ring (complete next descriptor here)
+ * @descriptors: Allocated descriptors for this ring
+ * @queue: Queue holding frames to be transferred over this ring
+ * @in_flight: Queue holding frames that are currently in flight
+ * @work: Interrupt work structure
+ * @is_tx: Is the ring Tx or Rx
+ * @running: Is the ring running
+ * @irq: MSI-X irq number if the ring uses MSI-X. %0 otherwise.
+ * @vector: MSI-X vector number the ring uses (only set if @irq is > 0)
+ * @flags: Ring specific flags
+ * @sof_mask: Bit mask used to detect start of frame PDF
+ * @eof_mask: Bit mask used to detect end of frame PDF
+ */
+struct tb_ring {
+	struct mutex lock;
+	struct tb_nhi *nhi;
+	int size;
+	int hop;
+	int head;
+	int tail;
+	struct ring_desc *descriptors;
+	dma_addr_t descriptors_dma;
+	struct list_head queue;
+	struct list_head in_flight;
+	struct work_struct work;
+	bool is_tx:1;
+	bool running:1;
+	int irq;
+	u8 vector;
+	unsigned int flags;
+	u16 sof_mask;
+	u16 eof_mask;
+};
+
+/* Leave ring interrupt enabled on suspend */
+#define RING_FLAG_NO_SUSPEND	BIT(0)
+/* Configure the ring to be in frame mode */
+#define RING_FLAG_FRAME		BIT(1)
+/* Enable end-to-end flow control */
+#define RING_FLAG_E2E		BIT(2)
+
+struct ring_frame;
+typedef void (*ring_cb)(struct tb_ring *, struct ring_frame *, bool canceled);
+
+/**
+ * struct ring_frame - For use with ring_rx/ring_tx
+ * @buffer_phy: DMA mapped address of the frame
+ * @callback: Callback called when the frame is finished
+ * @list: Frame is linked to a queue using this
+ * @size: Size of the frame in bytes (%0 means %4096)
+ * @flags: Flags for the frame (see &enum ring_desc_flags)
+ * @eof: End of frame protocol defined field
+ * @sof: Start of frame protocol defined field
+ */
+struct ring_frame {
+	dma_addr_t buffer_phy;
+	ring_cb callback;
+	struct list_head list;
+	u32 size:12;
+	u32 flags:12;
+	u32 eof:4;
+	u32 sof:4;
+};
+
+/* Minimum size for ring_rx */
+#define TB_FRAME_SIZE		0x100
+
+struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
+				 unsigned int flags);
+struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
+				 unsigned int flags, u16 sof_mask,
+				 u16 eof_mask);
+void tb_ring_start(struct tb_ring *ring);
+void tb_ring_stop(struct tb_ring *ring);
+void tb_ring_free(struct tb_ring *ring);
+
+int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame);
+
+/**
+ * tb_ring_rx() - enqueue a frame on an RX ring
+ * @ring: Ring to enqueue the frame
+ * @frame: Frame to enqueue
+ *
+ * @frame->buffer, @frame->buffer_phy and @frame->callback have to be set. The
+ * buffer must contain at least %TB_FRAME_SIZE bytes.
+ *
+ * @frame->callback will be invoked with @frame->size, @frame->flags,
+ * @frame->eof, @frame->sof set once the frame has been received.
+ *
+ * If ring_stop() is called after the packet has been enqueued
+ * @frame->callback will be called with canceled set to true.
+ *
+ * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
+ */
+static inline int tb_ring_rx(struct tb_ring *ring, struct ring_frame *frame)
+{
+	WARN_ON(ring->is_tx);
+	return __tb_ring_enqueue(ring, frame);
+}
+
+/**
+ * tb_ring_tx() - enqueue a frame on an TX ring
+ * @ring: Ring the enqueue the frame
+ * @frame: Frame to enqueue
+ *
+ * @frame->buffer, @frame->buffer_phy, @frame->callback, @frame->size,
+ * @frame->eof and @frame->sof have to be set.
+ *
+ * @frame->callback will be invoked with once the frame has been transmitted.
+ *
+ * If ring_stop() is called after the packet has been enqueued @frame->callback
+ * will be called with canceled set to true.
+ *
+ * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
+ */
+static inline int tb_ring_tx(struct tb_ring *ring, struct ring_frame *frame)
+{
+	WARN_ON(!ring->is_tx);
+	return __tb_ring_enqueue(ring, frame);
+}
+
 #endif /* THUNDERBOLT_H_ */
-- 
2.13.5

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#1734235 — [PATCH 12/16] thunderbolt: Use spinlock in NHI serialization

This is needed because ring polling functionality can be called from
atomic contexts when networking and other high-speed traffic is
transferred over a Thunderbolt cable.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 drivers/thunderbolt/nhi.c   | 75 +++++++++++++++++++++++++--------------------
 include/linux/thunderbolt.h |  2 +-
 2 files changed, 42 insertions(+), 35 deletions(-)

diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index d1ad37c6eccf..cf1397afa72f 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -327,21 +327,9 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 	if (transmit && hop == RING_E2E_UNUSED_HOPID)
 		return NULL;
 
-	mutex_lock(&nhi->lock);
-	if (hop >= nhi->hop_count) {
-		dev_WARN(&nhi->pdev->dev, "invalid hop: %d\n", hop);
-		goto err;
-	}
-	if (transmit && nhi->tx_rings[hop]) {
-		dev_WARN(&nhi->pdev->dev, "TX hop %d already allocated\n", hop);
-		goto err;
-	} else if (!transmit && nhi->rx_rings[hop]) {
-		dev_WARN(&nhi->pdev->dev, "RX hop %d already allocated\n", hop);
-		goto err;
-	}
 	ring = kzalloc(sizeof(*ring), GFP_KERNEL);
 	if (!ring)
-		goto err;
+		return NULL;
 
 	spin_lock_init(&ring->lock);
 	INIT_LIST_HEAD(&ring->queue);
@@ -359,25 +347,45 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 	ring->tail = 0;
 	ring->running = false;
 
-	if (ring_request_msix(ring, flags & RING_FLAG_NO_SUSPEND))
-		goto err;
-
 	ring->descriptors = dma_alloc_coherent(&ring->nhi->pdev->dev,
 			size * sizeof(*ring->descriptors),
 			&ring->descriptors_dma, GFP_KERNEL | __GFP_ZERO);
 	if (!ring->descriptors)
-		goto err;
+		goto err_free_ring;
 
+	if (ring_request_msix(ring, flags & RING_FLAG_NO_SUSPEND))
+		goto err_free_descs;
+
+	spin_lock_irq(&nhi->lock);
+	if (hop >= nhi->hop_count) {
+		dev_WARN(&nhi->pdev->dev, "invalid hop: %d\n", hop);
+		goto err_release_msix;
+	}
+	if (transmit && nhi->tx_rings[hop]) {
+		dev_WARN(&nhi->pdev->dev, "TX hop %d already allocated\n", hop);
+		goto err_release_msix;
+	} else if (!transmit && nhi->rx_rings[hop]) {
+		dev_WARN(&nhi->pdev->dev, "RX hop %d already allocated\n", hop);
+		goto err_release_msix;
+	}
 	if (transmit)
 		nhi->tx_rings[hop] = ring;
 	else
 		nhi->rx_rings[hop] = ring;
-	mutex_unlock(&nhi->lock);
+	spin_unlock_irq(&nhi->lock);
+
 	return ring;
 
-err:
+err_release_msix:
+	spin_unlock_irq(&nhi->lock);
+	ring_release_msix(ring);
+err_free_descs:
+	dma_free_coherent(&ring->nhi->pdev->dev,
+			  ring->size * sizeof(*ring->descriptors),
+			  ring->descriptors, ring->descriptors_dma);
+err_free_ring:
 	kfree(ring);
-	mutex_unlock(&nhi->lock);
+
 	return NULL;
 }
 
@@ -421,8 +429,8 @@ void tb_ring_start(struct tb_ring *ring)
 	u16 frame_size;
 	u32 flags;
 
-	mutex_lock(&ring->nhi->lock);
-	spin_lock_irq(&ring->lock);
+	spin_lock_irq(&ring->nhi->lock);
+	spin_lock(&ring->lock);
 	if (ring->nhi->going_away)
 		goto err;
 	if (ring->running) {
@@ -469,8 +477,8 @@ void tb_ring_start(struct tb_ring *ring)
 	ring_interrupt_active(ring, true);
 	ring->running = true;
 err:
-	spin_unlock_irq(&ring->lock);
-	mutex_unlock(&ring->nhi->lock);
+	spin_unlock(&ring->lock);
+	spin_unlock_irq(&ring->nhi->lock);
 }
 EXPORT_SYMBOL_GPL(tb_ring_start);
 
@@ -489,8 +497,8 @@ EXPORT_SYMBOL_GPL(tb_ring_start);
  */
 void tb_ring_stop(struct tb_ring *ring)
 {
-	mutex_lock(&ring->nhi->lock);
-	spin_lock_irq(&ring->lock);
+	spin_lock_irq(&ring->nhi->lock);
+	spin_lock(&ring->lock);
 	dev_info(&ring->nhi->pdev->dev, "stopping %s %d\n",
 		 RING_TYPE(ring), ring->hop);
 	if (ring->nhi->going_away)
@@ -511,8 +519,8 @@ void tb_ring_stop(struct tb_ring *ring)
 	ring->running = false;
 
 err:
-	spin_unlock_irq(&ring->lock);
-	mutex_unlock(&ring->nhi->lock);
+	spin_unlock(&ring->lock);
+	spin_unlock_irq(&ring->nhi->lock);
 
 	/*
 	 * schedule ring->work to invoke callbacks on all remaining frames.
@@ -534,7 +542,7 @@ EXPORT_SYMBOL_GPL(tb_ring_stop);
  */
 void tb_ring_free(struct tb_ring *ring)
 {
-	mutex_lock(&ring->nhi->lock);
+	spin_lock_irq(&ring->nhi->lock);
 	/*
 	 * Dissociate the ring from the NHI. This also ensures that
 	 * nhi_interrupt_work cannot reschedule ring->work.
@@ -564,7 +572,7 @@ void tb_ring_free(struct tb_ring *ring)
 		 RING_TYPE(ring),
 		 ring->hop);
 
-	mutex_unlock(&ring->nhi->lock);
+	spin_unlock_irq(&ring->nhi->lock);
 	/**
 	 * ring->work can no longer be scheduled (it is scheduled only
 	 * by nhi_interrupt_work, ring_stop and ring_msix). Wait for it
@@ -639,7 +647,7 @@ static void nhi_interrupt_work(struct work_struct *work)
 	int type = 0; /* current interrupt type 0: TX, 1: RX, 2: RX overflow */
 	struct tb_ring *ring;
 
-	mutex_lock(&nhi->lock);
+	spin_lock_irq(&nhi->lock);
 
 	/*
 	 * Starting at REG_RING_NOTIFY_BASE there are three status bitfields
@@ -677,7 +685,7 @@ static void nhi_interrupt_work(struct work_struct *work)
 		/* we do not check ring->running, this is done in ring->work */
 		schedule_work(&ring->work);
 	}
-	mutex_unlock(&nhi->lock);
+	spin_unlock_irq(&nhi->lock);
 }
 
 static irqreturn_t nhi_msi(int irq, void *data)
@@ -766,7 +774,6 @@ static void nhi_shutdown(struct tb_nhi *nhi)
 		devm_free_irq(&nhi->pdev->dev, nhi->pdev->irq, nhi);
 		flush_work(&nhi->interrupt_work);
 	}
-	mutex_destroy(&nhi->lock);
 	ida_destroy(&nhi->msix_ida);
 }
 
@@ -855,7 +862,7 @@ static int nhi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		return res;
 	}
 
-	mutex_init(&nhi->lock);
+	spin_lock_init(&nhi->lock);
 
 	pci_set_master(pdev);
 
diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
index 51af0a5fa52f..62adb97d77f1 100644
--- a/include/linux/thunderbolt.h
+++ b/include/linux/thunderbolt.h
@@ -415,7 +415,7 @@ static inline struct tb_xdomain *tb_service_parent(struct tb_service *svc)
  * @hop_count: Number of rings (end point hops) supported by NHI.
  */
 struct tb_nhi {
-	struct mutex lock;
+	spinlock_t lock;
 	struct pci_dev *pdev;
 	void __iomem *iobase;
 	struct tb_ring **tx_rings;
-- 
2.13.5

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#1734236 — [PATCH 15/16] thunderbolt: Allocate ring HopID automatically if requested

Thunderbolt services should not care which HopID (ring) they use for
sending and receiving packets over the high-speed DMA path, so make
tb_ring_alloc_rx() and tb_ring_alloc_tx() accept negative HopID. This
means that the NHI will allocate next available HopID for the caller
automatically.

These HopIDs will be allocated from the range which is not reserved for
the Thunderbolt protocol (8 .. hop_count - 1).

The allocated HopID can be retrieved from ring->hop field after the ring
has been allocated successfully if needed.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 drivers/thunderbolt/nhi.c | 78 ++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 60 insertions(+), 18 deletions(-)

diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index 5bc3f77cc1f3..b9e3980aa4fc 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -26,6 +26,8 @@
  * use this ring for anything else.
  */
 #define RING_E2E_UNUSED_HOPID	2
+/* HopIDs 0-7 are reserved by the Thunderbolt protocol */
+#define RING_FIRST_USABLE_HOPID	8
 
 /*
  * Minimal number of vectors when we use MSI-X. Two for control channel
@@ -411,6 +413,62 @@ static void ring_release_msix(struct tb_ring *ring)
 	ring->irq = 0;
 }
 
+static int nhi_alloc_hop(struct tb_nhi *nhi, struct tb_ring *ring)
+{
+	int ret = 0;
+
+	spin_lock_irq(&nhi->lock);
+
+	if (ring->hop < 0) {
+		unsigned int i;
+
+		/*
+		 * Automatically allocate HopID from the non-reserved
+		 * range 8 .. hop_count - 1.
+		 */
+		for (i = RING_FIRST_USABLE_HOPID; i < nhi->hop_count; i++) {
+			if (ring->is_tx) {
+				if (!nhi->tx_rings[i]) {
+					ring->hop = i;
+					break;
+				}
+			} else {
+				if (!nhi->rx_rings[i]) {
+					ring->hop = i;
+					break;
+				}
+			}
+		}
+	}
+
+	if (ring->hop < 0 || ring->hop >= nhi->hop_count) {
+		dev_warn(&nhi->pdev->dev, "invalid hop: %d\n", ring->hop);
+		ret = -EINVAL;
+		goto err_unlock;
+	}
+	if (ring->is_tx && nhi->tx_rings[ring->hop]) {
+		dev_warn(&nhi->pdev->dev, "TX hop %d already allocated\n",
+			 ring->hop);
+		ret = -EBUSY;
+		goto err_unlock;
+	} else if (!ring->is_tx && nhi->rx_rings[ring->hop]) {
+		dev_warn(&nhi->pdev->dev, "RX hop %d already allocated\n",
+			 ring->hop);
+		ret = -EBUSY;
+		goto err_unlock;
+	}
+
+	if (ring->is_tx)
+		nhi->tx_rings[ring->hop] = ring;
+	else
+		nhi->rx_rings[ring->hop] = ring;
+
+err_unlock:
+	spin_unlock_irq(&nhi->lock);
+
+	return ret;
+}
+
 static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 				     bool transmit, unsigned int flags,
 				     u16 sof_mask, u16 eof_mask,
@@ -456,28 +514,12 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 	if (ring_request_msix(ring, flags & RING_FLAG_NO_SUSPEND))
 		goto err_free_descs;
 
-	spin_lock_irq(&nhi->lock);
-	if (hop >= nhi->hop_count) {
-		dev_WARN(&nhi->pdev->dev, "invalid hop: %d\n", hop);
+	if (nhi_alloc_hop(nhi, ring))
 		goto err_release_msix;
-	}
-	if (transmit && nhi->tx_rings[hop]) {
-		dev_WARN(&nhi->pdev->dev, "TX hop %d already allocated\n", hop);
-		goto err_release_msix;
-	} else if (!transmit && nhi->rx_rings[hop]) {
-		dev_WARN(&nhi->pdev->dev, "RX hop %d already allocated\n", hop);
-		goto err_release_msix;
-	}
-	if (transmit)
-		nhi->tx_rings[hop] = ring;
-	else
-		nhi->rx_rings[hop] = ring;
-	spin_unlock_irq(&nhi->lock);
 
 	return ring;
 
 err_release_msix:
-	spin_unlock_irq(&nhi->lock);
 	ring_release_msix(ring);
 err_free_descs:
 	dma_free_coherent(&ring->nhi->pdev->dev,
@@ -506,7 +548,7 @@ EXPORT_SYMBOL_GPL(tb_ring_alloc_tx);
 /**
  * tb_ring_alloc_rx() - Allocate DMA ring for receive
  * @nhi: Pointer to the NHI the ring is to be allocated
- * @hop: HopID (ring) to allocate
+ * @hop: HopID (ring) to allocate. Pass %-1 for automatic allocation.
  * @size: Number of entries in the ring
  * @flags: Flags for the ring
  * @sof_mask: Mask of PDF values that start a frame
-- 
2.13.5

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#1734237 — [PATCH 10/16] thunderbolt: Move ring descriptor flags to thunderbolt.h

A Thunderbolt service driver might need to check if there was an error
with the descriptor when in frame mode. We also add two Rx specific
error flags RING_DESC_CRC_ERROR and RING_DESC_BUFFER_OVERRUN.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 drivers/thunderbolt/nhi_regs.h |  7 -------
 include/linux/thunderbolt.h    | 18 ++++++++++++++++++
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/thunderbolt/nhi_regs.h b/drivers/thunderbolt/nhi_regs.h
index 491a4c0c18fc..5ed6934e31e7 100644
--- a/drivers/thunderbolt/nhi_regs.h
+++ b/drivers/thunderbolt/nhi_regs.h
@@ -17,13 +17,6 @@ enum ring_flags {
 	RING_FLAG_ENABLE = 1 << 31,
 };
 
-enum ring_desc_flags {
-	RING_DESC_ISOCH = 0x1, /* TX only? */
-	RING_DESC_COMPLETED = 0x2, /* set by NHI */
-	RING_DESC_POSTED = 0x4, /* always set this */
-	RING_DESC_INTERRUPT = 0x8, /* request an interrupt on completion */
-};
-
 /**
  * struct ring_desc - TX/RX ring entry
  *
diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
index 1a376374c327..fac4ff62c0de 100644
--- a/include/linux/thunderbolt.h
+++ b/include/linux/thunderbolt.h
@@ -479,6 +479,24 @@ struct ring_frame;
 typedef void (*ring_cb)(struct tb_ring *, struct ring_frame *, bool canceled);
 
 /**
+ * enum ring_desc_flags - Flags for DMA ring descriptor
+ * %RING_DESC_ISOCH: Enable isonchronous DMA (Tx only)
+ * %RING_DESC_CRC_ERROR: In frame mode CRC check failed for the frame (Rx only)
+ * %RING_DESC_COMPLETED: Descriptor completed (set by NHI)
+ * %RING_DESC_POSTED: Always set this
+ * %RING_DESC_BUFFER_OVERRUN: RX buffer overrun
+ * %RING_DESC_INTERRUPT: Request an interrupt on compltion
+ */
+enum ring_desc_flags {
+	RING_DESC_ISOCH = 0x1,
+	RING_DESC_CRC_ERROR = 0x1,
+	RING_DESC_COMPLETED = 0x2,
+	RING_DESC_POSTED = 0x4,
+	RING_DESC_BUFFER_OVERRUN = 0x04,
+	RING_DESC_INTERRUPT = 0x8,
+};
+
+/**
  * struct ring_frame - For use with ring_rx/ring_tx
  * @buffer_phy: DMA mapped address of the frame
  * @callback: Callback called when the frame is finished
-- 
2.13.5

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#1734238 — [PATCH 13/16] thunderbolt: Add polling mode for rings

In order to support things like networking over Thunderbolt cable, there
needs to be a way to switch the ring to a mode where it can be polled
with the interrupt masked. We implement such mode so that the caller can
allocate a ring by passing pointer to a function that is then called
when an interrupt is triggered. Completed frames can be fetched using
tb_ring_poll() and the interrupt can be re-enabled when the caller is
finished with polling by using tb_ring_poll_complete().

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 drivers/thunderbolt/ctl.c   |   2 +-
 drivers/thunderbolt/nhi.c   | 126 ++++++++++++++++++++++++++++++++++++++++----
 include/linux/thunderbolt.h |  23 +++++---
 3 files changed, 134 insertions(+), 17 deletions(-)

diff --git a/drivers/thunderbolt/ctl.c b/drivers/thunderbolt/ctl.c
index dd10789e1dbb..d079dbba2c03 100644
--- a/drivers/thunderbolt/ctl.c
+++ b/drivers/thunderbolt/ctl.c
@@ -619,7 +619,7 @@ struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, event_cb cb, void *cb_data)
 		goto err;
 
 	ctl->rx = tb_ring_alloc_rx(nhi, 0, 10, RING_FLAG_NO_SUSPEND, 0xffff,
-				0xffff);
+				0xffff, NULL, NULL);
 	if (!ctl->rx)
 		goto err;
 
diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index cf1397afa72f..5bc3f77cc1f3 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -252,7 +252,8 @@ static void ring_work(struct work_struct *work)
 		 * Do not hold on to it.
 		 */
 		list_del_init(&frame->list);
-		frame->callback(ring, frame, canceled);
+		if (frame->callback)
+			frame->callback(ring, frame, canceled);
 	}
 }
 
@@ -273,11 +274,106 @@ int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame)
 }
 EXPORT_SYMBOL_GPL(__tb_ring_enqueue);
 
+/**
+ * tb_ring_poll() - Poll one completed frame from the ring
+ * @ring: Ring to poll
+ *
+ * This function can be called when @start_poll callback of the @ring
+ * has been called. It will read one completed frame from the ring and
+ * return it to the caller. Returns %NULL if there is no more completed
+ * frames.
+ */
+struct ring_frame *tb_ring_poll(struct tb_ring *ring)
+{
+	struct ring_frame *frame = NULL;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ring->lock, flags);
+	if (!ring->running)
+		goto unlock;
+	if (ring_empty(ring))
+		goto unlock;
+
+	if (ring->descriptors[ring->tail].flags & RING_DESC_COMPLETED) {
+		frame = list_first_entry(&ring->in_flight, typeof(*frame),
+					 list);
+		list_del_init(&frame->list);
+
+		if (!ring->is_tx) {
+			frame->size = ring->descriptors[ring->tail].length;
+			frame->eof = ring->descriptors[ring->tail].eof;
+			frame->sof = ring->descriptors[ring->tail].sof;
+			frame->flags = ring->descriptors[ring->tail].flags;
+		}
+
+		ring->tail = (ring->tail + 1) % ring->size;
+	}
+
+unlock:
+	spin_unlock_irqrestore(&ring->lock, flags);
+	return frame;
+}
+EXPORT_SYMBOL_GPL(tb_ring_poll);
+
+static void __ring_interrupt_mask(struct tb_ring *ring, bool mask)
+{
+	int idx = ring_interrupt_index(ring);
+	int reg = REG_RING_INTERRUPT_BASE + idx / 32 * 4;
+	int bit = idx % 32;
+	u32 val;
+
+	val = ioread32(ring->nhi->iobase + reg);
+	if (mask)
+		val &= ~BIT(bit);
+	else
+		val |= BIT(bit);
+	iowrite32(val, ring->nhi->iobase + reg);
+}
+
+/* Both @nhi->lock and @ring->lock should be held */
+static void __ring_interrupt(struct tb_ring *ring)
+{
+	if (!ring->running)
+		return;
+
+	if (ring->start_poll) {
+		__ring_interrupt_mask(ring, false);
+		ring->start_poll(ring->poll_data);
+	} else {
+		schedule_work(&ring->work);
+	}
+}
+
+/**
+ * tb_ring_poll_complete() - Re-start interrupt for the ring
+ * @ring: Ring to re-start the interrupt
+ *
+ * This will re-start (unmask) the ring interrupt once the user is done
+ * with polling.
+ */
+void tb_ring_poll_complete(struct tb_ring *ring)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&ring->nhi->lock, flags);
+	spin_lock(&ring->lock);
+	if (ring->start_poll)
+		__ring_interrupt_mask(ring, false);
+	spin_unlock(&ring->lock);
+	spin_unlock_irqrestore(&ring->nhi->lock, flags);
+}
+EXPORT_SYMBOL_GPL(tb_ring_poll_complete);
+
 static irqreturn_t ring_msix(int irq, void *data)
 {
 	struct tb_ring *ring = data;
 
-	schedule_work(&ring->work);
+	spin_lock(&ring->nhi->lock);
+	spin_lock(&ring->lock);
+	__ring_interrupt(ring);
+	spin_unlock(&ring->lock);
+	spin_unlock(&ring->nhi->lock);
+
 	return IRQ_HANDLED;
 }
 
@@ -317,7 +413,9 @@ static void ring_release_msix(struct tb_ring *ring)
 
 static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 				     bool transmit, unsigned int flags,
-				     u16 sof_mask, u16 eof_mask)
+				     u16 sof_mask, u16 eof_mask,
+				     void (*start_poll)(void *),
+				     void *poll_data)
 {
 	struct tb_ring *ring = NULL;
 	dev_info(&nhi->pdev->dev, "allocating %s ring %d of size %d\n",
@@ -346,6 +444,8 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 	ring->head = 0;
 	ring->tail = 0;
 	ring->running = false;
+	ring->start_poll = start_poll;
+	ring->poll_data = poll_data;
 
 	ring->descriptors = dma_alloc_coherent(&ring->nhi->pdev->dev,
 			size * sizeof(*ring->descriptors),
@@ -399,7 +499,7 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
 				 unsigned int flags)
 {
-	return tb_ring_alloc(nhi, hop, size, true, flags, 0, 0);
+	return tb_ring_alloc(nhi, hop, size, true, flags, 0, 0, NULL, NULL);
 }
 EXPORT_SYMBOL_GPL(tb_ring_alloc_tx);
 
@@ -411,11 +511,17 @@ EXPORT_SYMBOL_GPL(tb_ring_alloc_tx);
  * @flags: Flags for the ring
  * @sof_mask: Mask of PDF values that start a frame
  * @eof_mask: Mask of PDF values that end a frame
+ * @start_poll: If not %NULL the ring will call this function when an
+ *		interrupt is triggered and masked, instead of callback
+ *		in each Rx frame.
+ * @poll_data: Optional data passed to @start_poll
  */
 struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
-				 unsigned int flags, u16 sof_mask, u16 eof_mask)
+				 unsigned int flags, u16 sof_mask, u16 eof_mask,
+				 void (*start_poll)(void *), void *poll_data)
 {
-	return tb_ring_alloc(nhi, hop, size, false, flags, sof_mask, eof_mask);
+	return tb_ring_alloc(nhi, hop, size, false, flags, sof_mask, eof_mask,
+			     start_poll, poll_data);
 }
 EXPORT_SYMBOL_GPL(tb_ring_alloc_rx);
 
@@ -556,6 +662,7 @@ void tb_ring_free(struct tb_ring *ring)
 		dev_WARN(&ring->nhi->pdev->dev, "%s %d still running\n",
 			 RING_TYPE(ring), ring->hop);
 	}
+	spin_unlock_irq(&ring->nhi->lock);
 
 	ring_release_msix(ring);
 
@@ -572,7 +679,6 @@ void tb_ring_free(struct tb_ring *ring)
 		 RING_TYPE(ring),
 		 ring->hop);
 
-	spin_unlock_irq(&ring->nhi->lock);
 	/**
 	 * ring->work can no longer be scheduled (it is scheduled only
 	 * by nhi_interrupt_work, ring_stop and ring_msix). Wait for it
@@ -682,8 +788,10 @@ static void nhi_interrupt_work(struct work_struct *work)
 				 hop);
 			continue;
 		}
-		/* we do not check ring->running, this is done in ring->work */
-		schedule_work(&ring->work);
+
+		spin_lock(&ring->lock);
+		__ring_interrupt(ring);
+		spin_unlock(&ring->lock);
 	}
 	spin_unlock_irq(&nhi->lock);
 }
diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
index 62adb97d77f1..9a63210d5084 100644
--- a/include/linux/thunderbolt.h
+++ b/include/linux/thunderbolt.h
@@ -446,6 +446,9 @@ struct tb_nhi {
  * @flags: Ring specific flags
  * @sof_mask: Bit mask used to detect start of frame PDF
  * @eof_mask: Bit mask used to detect end of frame PDF
+ * @start_poll: Called when ring interrupt is triggered to start
+ *		polling. Passing %NULL keeps the ring in interrupt mode.
+ * @poll_data: Data passed to @start_poll
  */
 struct tb_ring {
 	spinlock_t lock;
@@ -466,6 +469,8 @@ struct tb_ring {
 	unsigned int flags;
 	u16 sof_mask;
 	u16 eof_mask;
+	void (*start_poll)(void *data);
+	void *poll_data;
 };
 
 /* Leave ring interrupt enabled on suspend */
@@ -499,7 +504,7 @@ enum ring_desc_flags {
 /**
  * struct ring_frame - For use with ring_rx/ring_tx
  * @buffer_phy: DMA mapped address of the frame
- * @callback: Callback called when the frame is finished
+ * @callback: Callback called when the frame is finished (optional)
  * @list: Frame is linked to a queue using this
  * @size: Size of the frame in bytes (%0 means %4096)
  * @flags: Flags for the frame (see &enum ring_desc_flags)
@@ -522,8 +527,8 @@ struct ring_frame {
 struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
 				 unsigned int flags);
 struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
-				 unsigned int flags, u16 sof_mask,
-				 u16 eof_mask);
+				 unsigned int flags, u16 sof_mask, u16 eof_mask,
+				 void (*start_poll)(void *), void *poll_data);
 void tb_ring_start(struct tb_ring *ring);
 void tb_ring_stop(struct tb_ring *ring);
 void tb_ring_free(struct tb_ring *ring);
@@ -535,8 +540,8 @@ int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame);
  * @ring: Ring to enqueue the frame
  * @frame: Frame to enqueue
  *
- * @frame->buffer, @frame->buffer_phy and @frame->callback have to be set. The
- * buffer must contain at least %TB_FRAME_SIZE bytes.
+ * @frame->buffer, @frame->buffer_phy have to be set. The buffer must
+ * contain at least %TB_FRAME_SIZE bytes.
  *
  * @frame->callback will be invoked with @frame->size, @frame->flags,
  * @frame->eof, @frame->sof set once the frame has been received.
@@ -557,8 +562,8 @@ static inline int tb_ring_rx(struct tb_ring *ring, struct ring_frame *frame)
  * @ring: Ring the enqueue the frame
  * @frame: Frame to enqueue
  *
- * @frame->buffer, @frame->buffer_phy, @frame->callback, @frame->size,
- * @frame->eof and @frame->sof have to be set.
+ * @frame->buffer, @frame->buffer_phy, @frame->size, @frame->eof and
+ * @frame->sof have to be set.
  *
  * @frame->callback will be invoked with once the frame has been transmitted.
  *
@@ -573,4 +578,8 @@ static inline int tb_ring_tx(struct tb_ring *ring, struct ring_frame *frame)
 	return __tb_ring_enqueue(ring, frame);
 }
 
+/* Used only when the ring is in polling mode */
+struct ring_frame *tb_ring_poll(struct tb_ring *ring);
+void tb_ring_poll_complete(struct tb_ring *ring);
+
 #endif /* THUNDERBOLT_H_ */
-- 
2.13.5

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#1734242 — [PATCH 02/16] thunderbolt: Add support for XDomain properties

Thunderbolt XDomain discovery protocol uses directories which contain
properties and other directories to exchange information about what
capabilities the remote host supports. This also includes identification
information like device ID and name.

This adds support for parsing and formatting these properties and
establishes an API drivers can use in addition to the core Thunderbolt
driver. This API is exposed in a new header: include/linux/thunderbolt.h.

This code is based on the work done by Amir Levy and Michael Jamet.

Signed-off-by: Michael Jamet <michael.jamet@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 drivers/thunderbolt/Makefile   |   2 +-
 drivers/thunderbolt/property.c | 670 +++++++++++++++++++++++++++++++++++++++++
 include/linux/thunderbolt.h    |  89 ++++++
 3 files changed, 760 insertions(+), 1 deletion(-)
 create mode 100644 drivers/thunderbolt/property.c
 create mode 100644 include/linux/thunderbolt.h

diff --git a/drivers/thunderbolt/Makefile b/drivers/thunderbolt/Makefile
index 4900febc6c8a..7afd21f5383a 100644
--- a/drivers/thunderbolt/Makefile
+++ b/drivers/thunderbolt/Makefile
@@ -1,3 +1,3 @@
 obj-${CONFIG_THUNDERBOLT} := thunderbolt.o
 thunderbolt-objs := nhi.o ctl.o tb.o switch.o cap.o path.o tunnel_pci.o eeprom.o
-thunderbolt-objs += domain.o dma_port.o icm.o
+thunderbolt-objs += domain.o dma_port.o icm.o property.o
diff --git a/drivers/thunderbolt/property.c b/drivers/thunderbolt/property.c
new file mode 100644
index 000000000000..55a8aa32b1d6
--- /dev/null
+++ b/drivers/thunderbolt/property.c
@@ -0,0 +1,670 @@
+/*
+ * Thunderbolt XDomain property support
+ *
+ * Copyright (C) 2017, Intel Corporation
+ * Authors: Michael Jamet <michael.jamet@intel.com>
+ *          Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/uuid.h>
+#include <linux/thunderbolt.h>
+
+struct tb_property_entry {
+	u32 key_hi;
+	u32 key_lo;
+	u16 length;
+	u8 reserved;
+	u8 type;
+	u32 value;
+} __packed;
+
+struct tb_property_rootdir_entry {
+	u32 magic;
+	u32 length;
+	struct tb_property_entry entries[];
+} __packed;
+
+struct tb_property_dir_entry {
+	u32 uuid[4];
+	struct tb_property_entry entries[];
+} __packed;
+
+#define TB_PROPERTY_ROOTDIR_MAGIC	0x55584401
+
+static struct tb_property_dir *__tb_property_parse_dir(const u32 *block,
+	size_t block_len, unsigned int dir_offset, size_t dir_len,
+	bool is_root);
+
+static inline void parse_dwdata(void *dst, const void *src, size_t dwords)
+{
+	be32_to_cpu_array(dst, src, dwords);
+}
+
+static inline void format_dwdata(void *dst, const void *src, size_t dwords)
+{
+	cpu_to_be32_array(dst, src, dwords);
+}
+
+static bool tb_property_entry_valid(const struct tb_property_entry *entry,
+				  size_t block_len)
+{
+	switch (entry->type) {
+	case TB_PROPERTY_TYPE_DIRECTORY:
+	case TB_PROPERTY_TYPE_DATA:
+	case TB_PROPERTY_TYPE_TEXT:
+		if (entry->length > block_len)
+			return false;
+		if (entry->value + entry->length > block_len)
+			return false;
+		break;
+
+	case TB_PROPERTY_TYPE_VALUE:
+		if (entry->length != 1)
+			return false;
+		break;
+	}
+
+	return true;
+}
+
+static bool tb_property_key_valid(const char *key)
+{
+	return key && strlen(key) <= TB_PROPERTY_KEY_SIZE;
+}
+
+static struct tb_property *
+tb_property_alloc(const char *key, enum tb_property_type type)
+{
+	struct tb_property *property;
+
+	property = kzalloc(sizeof(*property), GFP_KERNEL);
+	if (!property)
+		return NULL;
+
+	strcpy(property->key, key);
+	property->type = type;
+	INIT_LIST_HEAD(&property->list);
+
+	return property;
+}
+
+static struct tb_property *tb_property_parse(const u32 *block, size_t block_len,
+					const struct tb_property_entry *entry)
+{
+	char key[TB_PROPERTY_KEY_SIZE + 1];
+	struct tb_property *property;
+	struct tb_property_dir *dir;
+
+	if (!tb_property_entry_valid(entry, block_len))
+		return NULL;
+
+	parse_dwdata(key, entry, 2);
+	key[TB_PROPERTY_KEY_SIZE] = '\0';
+
+	property = tb_property_alloc(key, entry->type);
+	if (!property)
+		return NULL;
+
+	property->length = entry->length;
+
+	switch (property->type) {
+	case TB_PROPERTY_TYPE_DIRECTORY:
+		dir = __tb_property_parse_dir(block, block_len, entry->value,
+					      entry->length, false);
+		if (!dir) {
+			kfree(property);
+			return NULL;
+		}
+		property->value.dir = dir;
+		break;
+
+	case TB_PROPERTY_TYPE_DATA:
+		property->value.data = kcalloc(property->length, sizeof(u32),
+					       GFP_KERNEL);
+		if (!property->value.data) {
+			kfree(property);
+			return NULL;
+		}
+		parse_dwdata(property->value.data, block + entry->value,
+			     entry->length);
+		break;
+
+	case TB_PROPERTY_TYPE_TEXT:
+		property->value.text = kcalloc(property->length, sizeof(u32),
+					       GFP_KERNEL);
+		if (!property->value.text) {
+			kfree(property);
+			return NULL;
+		}
+		parse_dwdata(property->value.text, block + entry->value,
+			     entry->length);
+		/* Force null termination */
+		property->value.text[property->length * 4 - 1] = '\0';
+		break;
+
+	case TB_PROPERTY_TYPE_VALUE:
+		property->value.immediate = entry->value;
+		break;
+
+	default:
+		property->type = TB_PROPERTY_TYPE_UNKNOWN;
+		break;
+	}
+
+	return property;
+}
+
+static struct tb_property_dir *__tb_property_parse_dir(const u32 *block,
+	size_t block_len, unsigned int dir_offset, size_t dir_len, bool is_root)
+{
+	const struct tb_property_entry *entries;
+	size_t i, content_len, nentries;
+	unsigned int content_offset;
+	struct tb_property_dir *dir;
+
+	dir = kzalloc(sizeof(*dir), GFP_KERNEL);
+	if (!dir)
+		return NULL;
+
+	if (is_root) {
+		content_offset = dir_offset + 2;
+		content_len = dir_len;
+	} else {
+		dir->uuid = kmemdup(&block[dir_offset], sizeof(*dir->uuid),
+				    GFP_KERNEL);
+		content_offset = dir_offset + 4;
+		content_len = dir_len - 4; /* Length includes UUID */
+	}
+
+	entries = (const struct tb_property_entry *)&block[content_offset];
+	nentries = content_len / (sizeof(*entries) / 4);
+
+	INIT_LIST_HEAD(&dir->properties);
+
+	for (i = 0; i < nentries; i++) {
+		struct tb_property *property;
+
+		property = tb_property_parse(block, block_len, &entries[i]);
+		if (!property) {
+			tb_property_free_dir(dir);
+			return NULL;
+		}
+
+		list_add_tail(&property->list, &dir->properties);
+	}
+
+	return dir;
+}
+
+/**
+ * tb_property_parse_dir() - Parses properties from given property block
+ * @block: Property block to parse
+ * @block_len: Number of dword elements in the property block
+ *
+ * This function parses the XDomain properties data block into format that
+ * can be traversed using the helper functions provided by this module.
+ * Upon success returns the parsed directory. In case of error returns
+ * %NULL. The resulting &struct tb_property_dir needs to be released by
+ * calling tb_property_free_dir() when not needed anymore.
+ *
+ * The @block is expected to be root directory.
+ */
+struct tb_property_dir *tb_property_parse_dir(const u32 *block,
+					      size_t block_len)
+{
+	const struct tb_property_rootdir_entry *rootdir =
+		(const struct tb_property_rootdir_entry *)block;
+
+	if (rootdir->magic != TB_PROPERTY_ROOTDIR_MAGIC)
+		return NULL;
+	if (rootdir->length > block_len)
+		return NULL;
+
+	return __tb_property_parse_dir(block, block_len, 0, rootdir->length,
+				       true);
+}
+
+/**
+ * tb_property_create_dir() - Creates new property directory
+ * @uuid: UUID used to identify the particular directory
+ *
+ * Creates new, empty property directory. If @uuid is %NULL then the
+ * directory is assumed to be root directory.
+ */
+struct tb_property_dir *tb_property_create_dir(const uuid_t *uuid)
+{
+	struct tb_property_dir *dir;
+
+	dir = kzalloc(sizeof(*dir), GFP_KERNEL);
+	if (!dir)
+		return NULL;
+
+	INIT_LIST_HEAD(&dir->properties);
+	if (uuid) {
+		dir->uuid = kmemdup(uuid, sizeof(*dir->uuid), GFP_KERNEL);
+		if (!dir->uuid) {
+			kfree(dir);
+			return NULL;
+		}
+	}
+
+	return dir;
+}
+EXPORT_SYMBOL_GPL(tb_property_create_dir);
+
+static void tb_property_free(struct tb_property *property)
+{
+	switch (property->type) {
+	case TB_PROPERTY_TYPE_DIRECTORY:
+		tb_property_free_dir(property->value.dir);
+		break;
+
+	case TB_PROPERTY_TYPE_DATA:
+		kfree(property->value.data);
+		break;
+
+	case TB_PROPERTY_TYPE_TEXT:
+		kfree(property->value.text);
+		break;
+
+	default:
+		break;
+	}
+
+	kfree(property);
+}
+
+/**
+ * tb_property_free_dir() - Release memory allocated for property directory
+ * @dir: Directory to release
+ *
+ * This will release all the memory the directory occupies including all
+ * descendants. It is OK to pass %NULL @dir, then the function does
+ * nothing.
+ */
+void tb_property_free_dir(struct tb_property_dir *dir)
+{
+	struct tb_property *property, *tmp;
+
+	if (!dir)
+		return;
+
+	list_for_each_entry_safe(property, tmp, &dir->properties, list) {
+		list_del(&property->list);
+		tb_property_free(property);
+	}
+	kfree(dir->uuid);
+	kfree(dir);
+}
+EXPORT_SYMBOL_GPL(tb_property_free_dir);
+
+static size_t tb_property_dir_length(const struct tb_property_dir *dir,
+				     bool recurse, size_t *data_len)
+{
+	const struct tb_property *property;
+	size_t len = 0;
+
+	if (dir->uuid)
+		len += sizeof(*dir->uuid) / 4;
+	else
+		len += sizeof(struct tb_property_rootdir_entry) / 4;
+
+	list_for_each_entry(property, &dir->properties, list) {
+		len += sizeof(struct tb_property_entry) / 4;
+
+		switch (property->type) {
+		case TB_PROPERTY_TYPE_DIRECTORY:
+			if (recurse) {
+				len += tb_property_dir_length(
+					property->value.dir, recurse, data_len);
+			}
+			/* Reserve dword padding after each directory */
+			if (data_len)
+				*data_len += 1;
+			break;
+
+		case TB_PROPERTY_TYPE_DATA:
+		case TB_PROPERTY_TYPE_TEXT:
+			if (data_len)
+				*data_len += property->length;
+			break;
+
+		default:
+			break;
+		}
+	}
+
+	return len;
+}
+
+static ssize_t __tb_property_format_dir(const struct tb_property_dir *dir,
+	u32 *block, unsigned int start_offset, size_t block_len)
+{
+	unsigned int data_offset, dir_end;
+	const struct tb_property *property;
+	struct tb_property_entry *entry;
+	size_t dir_len, data_len = 0;
+	int ret;
+
+	/*
+	 * The structure of property block looks like following. Leaf
+	 * data/text is included right after the directory and each
+	 * directory follows each other (even nested ones).
+	 *
+	 * +----------+ <-- start_offset
+	 * |  header  | <-- root directory header
+	 * +----------+ ---
+	 * |  entry 0 | -^--------------------.
+	 * +----------+  |                    |
+	 * |  entry 1 | -|--------------------|--.
+	 * +----------+  |                    |  |
+	 * |  entry 2 | -|-----------------.  |  |
+	 * +----------+  |                 |  |  |
+	 * :          :  |  dir_len        |  |  |
+	 * .          .  |                 |  |  |
+	 * :          :  |                 |  |  |
+	 * +----------+  |                 |  |  |
+	 * |  entry n |  v                 |  |  |
+	 * +----------+ <-- data_offset    |  |  |
+	 * |  data 0  | <------------------|--'  |
+	 * +----------+                    |     |
+	 * |  data 1  | <------------------|-----'
+	 * +----------+                    |
+	 * | 00000000 | padding            |
+	 * +----------+ <-- dir_end <------'
+	 * |   UUID   | <-- directory UUID (child directory)
+	 * +----------+
+	 * |  entry 0 |
+	 * +----------+
+	 * |  entry 1 |
+	 * +----------+
+	 * :          :
+	 * .          .
+	 * :          :
+	 * +----------+
+	 * |  entry n |
+	 * +----------+
+	 * |  data 0  |
+	 * +----------+
+	 *
+	 * We use dir_end to hold pointer to the end of the directory. It
+	 * will increase as we add directories and each directory should be
+	 * added starting from previous dir_end.
+	 */
+	dir_len = tb_property_dir_length(dir, false, &data_len);
+	data_offset = start_offset + dir_len;
+	dir_end = start_offset + data_len + dir_len;
+
+	if (data_offset > dir_end)
+		return -EINVAL;
+	if (dir_end > block_len)
+		return -EINVAL;
+
+	/* Write headers first */
+	if (dir->uuid) {
+		struct tb_property_dir_entry *pe;
+
+		pe = (struct tb_property_dir_entry *)&block[start_offset];
+		memcpy(pe->uuid, dir->uuid, sizeof(pe->uuid));
+		entry = pe->entries;
+	} else {
+		struct tb_property_rootdir_entry *re;
+
+		re = (struct tb_property_rootdir_entry *)&block[start_offset];
+		re->magic = TB_PROPERTY_ROOTDIR_MAGIC;
+		re->length = dir_len - sizeof(*re) / 4;
+		entry = re->entries;
+	}
+
+	list_for_each_entry(property, &dir->properties, list) {
+		const struct tb_property_dir *child;
+
+		format_dwdata(entry, property->key, 2);
+		entry->type = property->type;
+
+		switch (property->type) {
+		case TB_PROPERTY_TYPE_DIRECTORY:
+			child = property->value.dir;
+			ret = __tb_property_format_dir(child, block, dir_end,
+						       block_len);
+			if (ret < 0)
+				return ret;
+			entry->length = tb_property_dir_length(child, false,
+							       NULL);
+			entry->value = dir_end;
+			dir_end = ret;
+			break;
+
+		case TB_PROPERTY_TYPE_DATA:
+			format_dwdata(&block[data_offset], property->value.data,
+				      property->length);
+			entry->length = property->length;
+			entry->value = data_offset;
+			data_offset += entry->length;
+			break;
+
+		case TB_PROPERTY_TYPE_TEXT:
+			format_dwdata(&block[data_offset], property->value.text,
+				      property->length);
+			entry->length = property->length;
+			entry->value = data_offset;
+			data_offset += entry->length;
+			break;
+
+		case TB_PROPERTY_TYPE_VALUE:
+			entry->length = property->length;
+			entry->value = property->value.immediate;
+			break;
+
+		default:
+			break;
+		}
+
+		entry++;
+	}
+
+	return dir_end;
+}
+
+/**
+ * tb_property_format_dir() - Formats directory to the packed XDomain format
+ * @dir: Directory to format
+ * @block: Property block where the packed data is placed
+ * @block_len: Length of the property block
+ *
+ * This function formats the directory to the packed format that can be
+ * then send over the thunderbolt fabric to receiving host. Returns %0 in
+ * case of success and negative errno on faulure. Passing %NULL in @block
+ * returns number of entries the block takes.
+ */
+ssize_t tb_property_format_dir(const struct tb_property_dir *dir, u32 *block,
+			       size_t block_len)
+{
+	ssize_t ret;
+
+	if (!block) {
+		size_t dir_len, data_len = 0;
+
+		dir_len = tb_property_dir_length(dir, true, &data_len);
+		return dir_len + data_len;
+	}
+
+	ret = __tb_property_format_dir(dir, block, 0, block_len);
+	return ret < 0 ? ret : 0;
+}
+
+/**
+ * tb_property_add_immediate() - Add immediate property to directory
+ * @parent: Directory to add the property
+ * @key: Key for the property
+ * @value: Immediate value to store with the property
+ */
+int tb_property_add_immediate(struct tb_property_dir *parent, const char *key,
+			      u32 value)
+{
+	struct tb_property *property;
+
+	if (!tb_property_key_valid(key))
+		return -EINVAL;
+
+	property = tb_property_alloc(key, TB_PROPERTY_TYPE_VALUE);
+	if (!property)
+		return -ENOMEM;
+
+	property->length = 1;
+	property->value.immediate = value;
+
+	list_add_tail(&property->list, &parent->properties);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tb_property_add_immediate);
+
+/**
+ * tb_property_add_data() - Adds arbitrary data property to directory
+ * @parent: Directory to add the property
+ * @key: Key for the property
+ * @buf: Data buffer to add
+ * @buflen: Number of bytes in the data buffer
+ *
+ * Function takes a copy of @buf and adds it to the directory.
+ */
+int tb_property_add_data(struct tb_property_dir *parent, const char *key,
+			 const void *buf, size_t buflen)
+{
+	/* Need to pad to dword boundary */
+	size_t size = round_up(buflen, 4);
+	struct tb_property *property;
+
+	if (!tb_property_key_valid(key))
+		return -EINVAL;
+
+	property = tb_property_alloc(key, TB_PROPERTY_TYPE_DATA);
+	if (!property)
+		return -ENOMEM;
+
+	property->length = size / 4;
+	property->value.data = kzalloc(size, GFP_KERNEL);
+	memcpy(property->value.data, buf, buflen);
+
+	list_add_tail(&property->list, &parent->properties);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tb_property_add_data);
+
+/**
+ * tb_property_add_text() - Adds string property to directory
+ * @parent: Directory to add the property
+ * @key: Key for the property
+ * @text: String to add
+ *
+ * Function takes a copy of @text and adds it to the directory.
+ */
+int tb_property_add_text(struct tb_property_dir *parent, const char *key,
+			 const char *text)
+{
+	/* Need to pad to dword boundary */
+	size_t size = round_up(strlen(text) + 1, 4);
+	struct tb_property *property;
+
+	if (!tb_property_key_valid(key))
+		return -EINVAL;
+
+	property = tb_property_alloc(key, TB_PROPERTY_TYPE_TEXT);
+	if (!property)
+		return -ENOMEM;
+
+	property->length = size / 4;
+	property->value.data = kzalloc(size, GFP_KERNEL);
+	strcpy(property->value.text, text);
+
+	list_add_tail(&property->list, &parent->properties);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tb_property_add_text);
+
+/**
+ * tb_property_add_dir() - Adds a directory to the parent directory
+ * @parent: Directory to add the property
+ * @key: Key for the property
+ * @dir: Directory to add
+ */
+int tb_property_add_dir(struct tb_property_dir *parent, const char *key,
+			struct tb_property_dir *dir)
+{
+	struct tb_property *property;
+
+	if (!tb_property_key_valid(key))
+		return -EINVAL;
+
+	property = tb_property_alloc(key, TB_PROPERTY_TYPE_DIRECTORY);
+	if (!property)
+		return -ENOMEM;
+
+	property->value.dir = dir;
+
+	list_add_tail(&property->list, &parent->properties);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tb_property_add_dir);
+
+/**
+ * tb_property_remove() - Removes property from a parent directory
+ * @property: Property to remove
+ *
+ * Note memory for @property is released as well so it is not allowed to
+ * touch the object after call to this function.
+ */
+void tb_property_remove(struct tb_property *property)
+{
+	list_del(&property->list);
+	kfree(property);
+}
+EXPORT_SYMBOL_GPL(tb_property_remove);
+
+/**
+ * tb_property_find() - Find a property from a directory
+ * @dir: Directory where the property is searched
+ * @key: Key to look for
+ * @type: Type of the property
+ *
+ * Finds and returns property from the given directory. Does not recurse
+ * into sub-directories. Returns %NULL if the property was not found.
+ */
+struct tb_property *tb_property_find(struct tb_property_dir *dir,
+	const char *key, enum tb_property_type type)
+{
+	struct tb_property *property;
+
+	list_for_each_entry(property, &dir->properties, list) {
+		if (property->type == type && !strcmp(property->key, key))
+			return property;
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(tb_property_find);
+
+/**
+ * tb_property_get_next() - Get next property from directory
+ * @dir: Directory holding properties
+ * @prev: Previous property in the directory (%NULL returns the first)
+ */
+struct tb_property *tb_property_get_next(struct tb_property_dir *dir,
+					 struct tb_property *prev)
+{
+	if (prev) {
+		if (list_is_last(&prev->list, &dir->properties))
+			return NULL;
+		return list_next_entry(prev, list);
+	}
+	return list_first_entry_or_null(&dir->properties, struct tb_property,
+					list);
+}
+EXPORT_SYMBOL_GPL(tb_property_get_next);
diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
new file mode 100644
index 000000000000..5673a4b4becb
--- /dev/null
+++ b/include/linux/thunderbolt.h
@@ -0,0 +1,89 @@
+/*
+ * Thunderbolt service API
+ *
+ * Copyright (C) 2017, Intel Corporation
+ * Authors: Michael Jamet <michael.jamet@intel.com>
+ *          Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef THUNDERBOLT_H_
+#define THUNDERBOLT_H_
+
+#include <linux/list.h>
+#include <linux/uuid.h>
+
+/**
+ * struct tb_property_dir - XDomain property directory
+ * @uuid: Directory UUID or %NULL if root directory
+ * @properties: List of properties in this directory
+ *
+ * User needs to provide serialization if needed.
+ */
+struct tb_property_dir {
+	const uuid_t *uuid;
+	struct list_head properties;
+};
+
+enum tb_property_type {
+	TB_PROPERTY_TYPE_UNKNOWN,
+	TB_PROPERTY_TYPE_DIRECTORY = 0x44,
+	TB_PROPERTY_TYPE_DATA = 0x64,
+	TB_PROPERTY_TYPE_TEXT = 0x74,
+	TB_PROPERTY_TYPE_VALUE = 0x76,
+};
+
+#define TB_PROPERTY_KEY_SIZE	8
+
+/**
+ * struct tb_property - XDomain property
+ * @list: Used to link properties together in a directory
+ * @key: Key for the property (always terminated).
+ * @type: Type of the property
+ * @length: Length of the property data in dwords
+ * @value: Property value
+ *
+ * Users use @type to determine which field in @value is filled.
+ */
+struct tb_property {
+	struct list_head list;
+	char key[TB_PROPERTY_KEY_SIZE + 1];
+	enum tb_property_type type;
+	size_t length;
+	union {
+		struct tb_property_dir *dir;
+		u8 *data;
+		char *text;
+		u32 immediate;
+	} value;
+};
+
+struct tb_property_dir *tb_property_parse_dir(const u32 *block,
+					      size_t block_len);
+ssize_t tb_property_format_dir(const struct tb_property_dir *dir, u32 *block,
+			       size_t block_len);
+struct tb_property_dir *tb_property_create_dir(const uuid_t *uuid);
+void tb_property_free_dir(struct tb_property_dir *dir);
+int tb_property_add_immediate(struct tb_property_dir *parent, const char *key,
+			      u32 value);
+int tb_property_add_data(struct tb_property_dir *parent, const char *key,
+			 const void *buf, size_t buflen);
+int tb_property_add_text(struct tb_property_dir *parent, const char *key,
+			 const char *text);
+int tb_property_add_dir(struct tb_property_dir *parent, const char *key,
+			struct tb_property_dir *dir);
+void tb_property_remove(struct tb_property *tb_property);
+struct tb_property *tb_property_find(struct tb_property_dir *dir,
+			const char *key, enum tb_property_type type);
+struct tb_property *tb_property_get_next(struct tb_property_dir *dir,
+					 struct tb_property *prev);
+
+#define tb_property_for_each(dir, property)			\
+	for (property = tb_property_get_next(dir, NULL);	\
+	     property;						\
+	     property = tb_property_get_next(dir, property))
+
+#endif /* THUNDERBOLT_H_ */
-- 
2.13.5

[toc] | [prev] | [next] | [standalone]

#1734243 — [PATCH 08/16] thunderbolt: Add support for frame mode

When high-speed DMA paths are used to transfer arbitrary data over a
Thunderbolt link, DMA rings should be in frame mode instead of raw mode.
The latter is used by the control channel (ring 0). In frame mode each
data frame can hold up to 4kB payload.

This patch modifies the DMA ring code to allow configuring a ring to be
in frame mode by passing a new flag (RING_FLAG_FRAME) to the ring when
it is allocated. In addition there might be need to enable end-to-end
(E2E) workaround for the ring to prevent losing Rx frames in certain
situations. We add another flag (RING_FLAG_E2E) that can be used for
this purpose.

This code is based on the work done by Amir Levy and Michael Jamet.

Signed-off-by: Michael Jamet <michael.jamet@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 drivers/thunderbolt/ctl.c      |  3 +-
 drivers/thunderbolt/nhi.c      | 76 ++++++++++++++++++++++++++----------------
 drivers/thunderbolt/nhi.h      | 10 +++++-
 drivers/thunderbolt/nhi_regs.h |  2 ++
 4 files changed, 61 insertions(+), 30 deletions(-)

diff --git a/drivers/thunderbolt/ctl.c b/drivers/thunderbolt/ctl.c
index 46e393c5fd1d..05400b77dcd7 100644
--- a/drivers/thunderbolt/ctl.c
+++ b/drivers/thunderbolt/ctl.c
@@ -618,7 +618,8 @@ struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, event_cb cb, void *cb_data)
 	if (!ctl->tx)
 		goto err;
 
-	ctl->rx = ring_alloc_rx(nhi, 0, 10, RING_FLAG_NO_SUSPEND);
+	ctl->rx = ring_alloc_rx(nhi, 0, 10, RING_FLAG_NO_SUSPEND, 0xffff,
+				0xffff);
 	if (!ctl->rx)
 		goto err;
 
diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index bc44cbaaf05a..cde8b6d46147 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -22,6 +22,12 @@
 #define RING_TYPE(ring) ((ring)->is_tx ? "TX ring" : "RX ring")
 
 /*
+ * Used to enable end-to-end workaround for missing RX packets. Do not
+ * use this ring for anything else.
+ */
+#define RING_E2E_UNUSED_HOPID	2
+
+/*
  * Minimal number of vectors when we use MSI-X. Two for control channel
  * Rx/Tx and the rest four are for cross domain DMA paths.
  */
@@ -229,23 +235,6 @@ static void ring_work(struct work_struct *work)
 			frame->eof = ring->descriptors[ring->tail].eof;
 			frame->sof = ring->descriptors[ring->tail].sof;
 			frame->flags = ring->descriptors[ring->tail].flags;
-			if (frame->sof != 0)
-				dev_WARN(&ring->nhi->pdev->dev,
-					 "%s %d got unexpected SOF: %#x\n",
-					 RING_TYPE(ring), ring->hop,
-					 frame->sof);
-			/*
-			 * known flags:
-			 * raw not enabled, interupt not set: 0x2=0010
-			 * raw enabled: 0xa=1010
-			 * raw not enabled: 0xb=1011
-			 * partial frame (>MAX_FRAME_SIZE): 0xe=1110
-			 */
-			if (frame->flags != 0xa)
-				dev_WARN(&ring->nhi->pdev->dev,
-					 "%s %d got unexpected flags: %#x\n",
-					 RING_TYPE(ring), ring->hop,
-					 frame->flags);
 		}
 		ring->tail = (ring->tail + 1) % ring->size;
 	}
@@ -321,12 +310,17 @@ static void ring_release_msix(struct tb_ring *ring)
 }
 
 static struct tb_ring *ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
-				  bool transmit, unsigned int flags)
+				  bool transmit, unsigned int flags,
+				  u16 sof_mask, u16 eof_mask)
 {
 	struct tb_ring *ring = NULL;
 	dev_info(&nhi->pdev->dev, "allocating %s ring %d of size %d\n",
 		 transmit ? "TX" : "RX", hop, size);
 
+	/* Tx Ring 2 is reserved for E2E workaround */
+	if (transmit && hop == RING_E2E_UNUSED_HOPID)
+		return NULL;
+
 	mutex_lock(&nhi->lock);
 	if (hop >= nhi->hop_count) {
 		dev_WARN(&nhi->pdev->dev, "invalid hop: %d\n", hop);
@@ -353,6 +347,8 @@ static struct tb_ring *ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 	ring->is_tx = transmit;
 	ring->size = size;
 	ring->flags = flags;
+	ring->sof_mask = sof_mask;
+	ring->eof_mask = eof_mask;
 	ring->head = 0;
 	ring->tail = 0;
 	ring->running = false;
@@ -384,13 +380,13 @@ static struct tb_ring *ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 struct tb_ring *ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
 			      unsigned int flags)
 {
-	return ring_alloc(nhi, hop, size, true, flags);
+	return ring_alloc(nhi, hop, size, true, flags, 0, 0);
 }
 
 struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
-			      unsigned int flags)
+			      unsigned int flags, u16 sof_mask, u16 eof_mask)
 {
-	return ring_alloc(nhi, hop, size, false, flags);
+	return ring_alloc(nhi, hop, size, false, flags, sof_mask, eof_mask);
 }
 
 /**
@@ -400,6 +396,9 @@ struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
  */
 void ring_start(struct tb_ring *ring)
 {
+	u16 frame_size;
+	u32 flags;
+
 	mutex_lock(&ring->nhi->lock);
 	mutex_lock(&ring->lock);
 	if (ring->nhi->going_away)
@@ -411,18 +410,39 @@ void ring_start(struct tb_ring *ring)
 	dev_info(&ring->nhi->pdev->dev, "starting %s %d\n",
 		 RING_TYPE(ring), ring->hop);
 
+	if (ring->flags & RING_FLAG_FRAME) {
+		/* Means 4096 */
+		frame_size = 0;
+		flags = RING_FLAG_ENABLE;
+	} else {
+		frame_size = TB_FRAME_SIZE;
+		flags = RING_FLAG_ENABLE | RING_FLAG_RAW;
+	}
+
+	if (ring->flags & RING_FLAG_E2E && !ring->is_tx) {
+		u32 hop;
+
+		/*
+		 * In order not to lose Rx packets we enable end-to-end
+		 * workaround which transfers Rx credits to an unused Tx
+		 * HopID.
+		 */
+		hop = RING_E2E_UNUSED_HOPID << REG_RX_OPTIONS_E2E_HOP_SHIFT;
+		hop &= REG_RX_OPTIONS_E2E_HOP_MASK;
+		flags |= hop | RING_FLAG_E2E_FLOW_CONTROL;
+	}
+
 	ring_iowrite64desc(ring, ring->descriptors_dma, 0);
 	if (ring->is_tx) {
 		ring_iowrite32desc(ring, ring->size, 12);
 		ring_iowrite32options(ring, 0, 4); /* time releated ? */
-		ring_iowrite32options(ring,
-				      RING_FLAG_ENABLE | RING_FLAG_RAW, 0);
+		ring_iowrite32options(ring, flags, 0);
 	} else {
-		ring_iowrite32desc(ring,
-				   (TB_FRAME_SIZE << 16) | ring->size, 12);
-		ring_iowrite32options(ring, 0xffffffff, 4); /* SOF EOF mask */
-		ring_iowrite32options(ring,
-				      RING_FLAG_ENABLE | RING_FLAG_RAW, 0);
+		u32 sof_eof_mask = ring->sof_mask << 16 | ring->eof_mask;
+
+		ring_iowrite32desc(ring, (frame_size << 16) | ring->size, 12);
+		ring_iowrite32options(ring, sof_eof_mask, 4);
+		ring_iowrite32options(ring, flags, 0);
 	}
 	ring_interrupt_active(ring, true);
 	ring->running = true;
diff --git a/drivers/thunderbolt/nhi.h b/drivers/thunderbolt/nhi.h
index 0e05828983db..4503ddbeccb3 100644
--- a/drivers/thunderbolt/nhi.h
+++ b/drivers/thunderbolt/nhi.h
@@ -56,6 +56,8 @@ struct tb_nhi {
  * @irq: MSI-X irq number if the ring uses MSI-X. %0 otherwise.
  * @vector: MSI-X vector number the ring uses (only set if @irq is > 0)
  * @flags: Ring specific flags
+ * @sof_mask: Bit mask used to detect start of frame PDF
+ * @eof_mask: Bit mask used to detect end of frame PDF
  */
 struct tb_ring {
 	struct mutex lock;
@@ -74,10 +76,16 @@ struct tb_ring {
 	int irq;
 	u8 vector;
 	unsigned int flags;
+	u16 sof_mask;
+	u16 eof_mask;
 };
 
 /* Leave ring interrupt enabled on suspend */
 #define RING_FLAG_NO_SUSPEND	BIT(0)
+/* Configure the ring to be in frame mode */
+#define RING_FLAG_FRAME		BIT(1)
+/* Enable end-to-end flow control */
+#define RING_FLAG_E2E		BIT(2)
 
 struct ring_frame;
 typedef void (*ring_cb)(struct tb_ring*, struct ring_frame*, bool canceled);
@@ -100,7 +108,7 @@ struct ring_frame {
 struct tb_ring *ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
 			      unsigned int flags);
 struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
-			      unsigned int flags);
+			      unsigned int flags, u16 sof_mask, u16 eof_mask);
 void ring_start(struct tb_ring *ring);
 void ring_stop(struct tb_ring *ring);
 void ring_free(struct tb_ring *ring);
diff --git a/drivers/thunderbolt/nhi_regs.h b/drivers/thunderbolt/nhi_regs.h
index 46eff69b19ad..491a4c0c18fc 100644
--- a/drivers/thunderbolt/nhi_regs.h
+++ b/drivers/thunderbolt/nhi_regs.h
@@ -77,6 +77,8 @@ struct ring_desc {
  * ..: unknown
  */
 #define REG_RX_OPTIONS_BASE	0x29800
+#define REG_RX_OPTIONS_E2E_HOP_MASK	GENMASK(22, 12)
+#define REG_RX_OPTIONS_E2E_HOP_SHIFT	12
 
 /*
  * three bitfields: tx, rx, rx overflow
-- 
2.13.5

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#1734244 — [PATCH 11/16] thunderbolt: Use spinlock in ring serialization

This makes it possible to enqueue frames also from atomic context which
is needed for example, when networking packets are sent over a
Thunderbolt cable.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 drivers/thunderbolt/nhi.c   | 26 ++++++++++++++------------
 include/linux/thunderbolt.h |  2 +-
 2 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index 4704ccd20c84..d1ad37c6eccf 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -212,8 +212,10 @@ static void ring_work(struct work_struct *work)
 	struct tb_ring *ring = container_of(work, typeof(*ring), work);
 	struct ring_frame *frame;
 	bool canceled = false;
+	unsigned long flags;
 	LIST_HEAD(done);
-	mutex_lock(&ring->lock);
+
+	spin_lock_irqsave(&ring->lock, flags);
 
 	if (!ring->running) {
 		/*  Move all frames to done and mark them as canceled. */
@@ -241,7 +243,8 @@ static void ring_work(struct work_struct *work)
 	ring_write_descriptors(ring);
 
 invoke_callback:
-	mutex_unlock(&ring->lock); /* allow callbacks to schedule new work */
+	/* allow callbacks to schedule new work */
+	spin_unlock_irqrestore(&ring->lock, flags);
 	while (!list_empty(&done)) {
 		frame = list_first_entry(&done, typeof(*frame), list);
 		/*
@@ -255,15 +258,17 @@ static void ring_work(struct work_struct *work)
 
 int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame)
 {
+	unsigned long flags;
 	int ret = 0;
-	mutex_lock(&ring->lock);
+
+	spin_lock_irqsave(&ring->lock, flags);
 	if (ring->running) {
 		list_add_tail(&frame->list, &ring->queue);
 		ring_write_descriptors(ring);
 	} else {
 		ret = -ESHUTDOWN;
 	}
-	mutex_unlock(&ring->lock);
+	spin_unlock_irqrestore(&ring->lock, flags);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(__tb_ring_enqueue);
@@ -338,7 +343,7 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 	if (!ring)
 		goto err;
 
-	mutex_init(&ring->lock);
+	spin_lock_init(&ring->lock);
 	INIT_LIST_HEAD(&ring->queue);
 	INIT_LIST_HEAD(&ring->in_flight);
 	INIT_WORK(&ring->work, ring_work);
@@ -371,8 +376,6 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 	return ring;
 
 err:
-	if (ring)
-		mutex_destroy(&ring->lock);
 	kfree(ring);
 	mutex_unlock(&nhi->lock);
 	return NULL;
@@ -419,7 +422,7 @@ void tb_ring_start(struct tb_ring *ring)
 	u32 flags;
 
 	mutex_lock(&ring->nhi->lock);
-	mutex_lock(&ring->lock);
+	spin_lock_irq(&ring->lock);
 	if (ring->nhi->going_away)
 		goto err;
 	if (ring->running) {
@@ -466,7 +469,7 @@ void tb_ring_start(struct tb_ring *ring)
 	ring_interrupt_active(ring, true);
 	ring->running = true;
 err:
-	mutex_unlock(&ring->lock);
+	spin_unlock_irq(&ring->lock);
 	mutex_unlock(&ring->nhi->lock);
 }
 EXPORT_SYMBOL_GPL(tb_ring_start);
@@ -487,7 +490,7 @@ EXPORT_SYMBOL_GPL(tb_ring_start);
 void tb_ring_stop(struct tb_ring *ring)
 {
 	mutex_lock(&ring->nhi->lock);
-	mutex_lock(&ring->lock);
+	spin_lock_irq(&ring->lock);
 	dev_info(&ring->nhi->pdev->dev, "stopping %s %d\n",
 		 RING_TYPE(ring), ring->hop);
 	if (ring->nhi->going_away)
@@ -508,7 +511,7 @@ void tb_ring_stop(struct tb_ring *ring)
 	ring->running = false;
 
 err:
-	mutex_unlock(&ring->lock);
+	spin_unlock_irq(&ring->lock);
 	mutex_unlock(&ring->nhi->lock);
 
 	/*
@@ -568,7 +571,6 @@ void tb_ring_free(struct tb_ring *ring)
 	 * to finish before freeing the ring.
 	 */
 	flush_work(&ring->work);
-	mutex_destroy(&ring->lock);
 	kfree(ring);
 }
 EXPORT_SYMBOL_GPL(tb_ring_free);
diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
index fac4ff62c0de..51af0a5fa52f 100644
--- a/include/linux/thunderbolt.h
+++ b/include/linux/thunderbolt.h
@@ -448,7 +448,7 @@ struct tb_nhi {
  * @eof_mask: Bit mask used to detect end of frame PDF
  */
 struct tb_ring {
-	struct mutex lock;
+	spinlock_t lock;
 	struct tb_nhi *nhi;
 	int size;
 	int hop;
-- 
2.13.5

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#1734245 — [PATCH 07/16] thunderbolt: Configure interrupt throttling for all interrupts

This will keep the interrupt delivery rate reasonable. The value used
here (128 us) is a recommendation from the hardware people.

This code is based on the work done by Amir Levy and Michael Jamet.

Signed-off-by: Michael Jamet <michael.jamet@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
---
 drivers/thunderbolt/nhi.c      | 22 +++++++++++++++++++---
 drivers/thunderbolt/nhi_regs.h |  2 ++
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index 05af126a2435..bc44cbaaf05a 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -651,6 +651,21 @@ static int nhi_suspend_noirq(struct device *dev)
 	return tb_domain_suspend_noirq(tb);
 }
 
+static void nhi_enable_int_throttling(struct tb_nhi *nhi)
+{
+	u32 throttle = DIV_ROUND_UP(128 * NSEC_PER_USEC, 256);
+	unsigned int i;
+
+	/*
+	 * Configure interrupt throttling for all vectors even if we
+	 * only use few.
+	 */
+	for (i = 0; i < MSIX_MAX_VECS; i++) {
+		u32 reg = REG_INT_THROTTLING_RATE + i * 4;
+		iowrite32(throttle, nhi->iobase + reg);
+	}
+}
+
 static int nhi_resume_noirq(struct device *dev)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
@@ -663,6 +678,8 @@ static int nhi_resume_noirq(struct device *dev)
 	 */
 	if (!pci_device_is_present(pdev))
 		tb->nhi->going_away = true;
+	else
+		nhi_enable_int_throttling(tb->nhi);
 
 	return tb_domain_resume_noirq(tb);
 }
@@ -717,6 +734,8 @@ static int nhi_init_msi(struct tb_nhi *nhi)
 	/* In case someone left them on. */
 	nhi_disable_interrupts(nhi);
 
+	nhi_enable_int_throttling(nhi);
+
 	ida_init(&nhi->msix_ida);
 
 	/*
@@ -796,9 +815,6 @@ static int nhi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	pci_set_master(pdev);
 
-	/* magic value - clock related? */
-	iowrite32(3906250 / 10000, nhi->iobase + 0x38c00);
-
 	tb = icm_probe(nhi);
 	if (!tb)
 		tb = tb_probe(nhi);
diff --git a/drivers/thunderbolt/nhi_regs.h b/drivers/thunderbolt/nhi_regs.h
index 09ed574e92ff..46eff69b19ad 100644
--- a/drivers/thunderbolt/nhi_regs.h
+++ b/drivers/thunderbolt/nhi_regs.h
@@ -95,6 +95,8 @@ struct ring_desc {
 #define REG_RING_INTERRUPT_BASE	0x38200
 #define RING_INTERRUPT_REG_COUNT(nhi) ((31 + 2 * nhi->hop_count) / 32)
 
+#define REG_INT_THROTTLING_RATE	0x38c00
+
 /* Interrupt Vector Allocation */
 #define REG_INT_VEC_ALLOC_BASE	0x38c40
 #define REG_INT_VEC_ALLOC_BITS	4
-- 
2.13.5

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#1734539 — Re: [PATCH 16/16] thunderbolt: Add support for networking over Thunderbolt cable

On Mon, Sep 18, 2017 at 06:30:49PM +0300, Mika Westerberg wrote:
> From: Amir Levy <amir.jer.levy@intel.com>
> 
> ThunderboltIP is a protocol created by Apple to tunnel IP/ethernet
> traffic over a Thunderbolt cable. The protocol consists of configuration
> phase where each side sends ThunderboltIP login packets (the protocol is
> determined by UUID in the XDomain packet header) over the configuration
> channel. Once both sides get positive acknowledgment to their login
> packet, they configure high-speed DMA path accordingly. This DMA path is
> then used to transmit and receive networking traffic.
> 
> This patch creates a virtual ethernet interface the host software can
> use in the same way as any other networking interface. Once the
> interface is brought up successfully network packets get tunneled over
> the Thunderbolt cable to the remote host and back.
> 
> The connection is terminated by sending a ThunderboltIP logout packet
> over the configuration channel. We do this when the network interface is
> brought down by user or the driver is unloaded.
> 
> Signed-off-by: Amir Levy <amir.jer.levy@intel.com>
> Signed-off-by: Michael Jamet <michael.jamet@intel.com>
> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
> ---
>  Documentation/admin-guide/thunderbolt.rst |   24 +
>  drivers/thunderbolt/Kconfig               |   12 +
>  drivers/thunderbolt/Makefile              |    3 +
>  drivers/thunderbolt/net.c                 | 1392 +++++++++++++++++++++++++++++
>  4 files changed, 1431 insertions(+)
>  create mode 100644 drivers/thunderbolt/net.c

Hi Mika

Could this be renamed to driver/net/thunderbolt.c?

At minimum, it needs a MAINTAINER entry pointing to netdev, so patches
get reviewed by netdev people. However, since the driver seems to be a
lot more netdev than thunderbolt, placing it in driver/net could be
better.

	Thanks
		Andrew

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#1734707 — Re: [PATCH 16/16] thunderbolt: Add support for networking over Thunderbolt cable

On Tue, Sep 19, 2017 at 01:21:44AM +0200, Andrew Lunn wrote:
> On Mon, Sep 18, 2017 at 06:30:49PM +0300, Mika Westerberg wrote:
> > From: Amir Levy <amir.jer.levy@intel.com>
> > 
> > ThunderboltIP is a protocol created by Apple to tunnel IP/ethernet
> > traffic over a Thunderbolt cable. The protocol consists of configuration
> > phase where each side sends ThunderboltIP login packets (the protocol is
> > determined by UUID in the XDomain packet header) over the configuration
> > channel. Once both sides get positive acknowledgment to their login
> > packet, they configure high-speed DMA path accordingly. This DMA path is
> > then used to transmit and receive networking traffic.
> > 
> > This patch creates a virtual ethernet interface the host software can
> > use in the same way as any other networking interface. Once the
> > interface is brought up successfully network packets get tunneled over
> > the Thunderbolt cable to the remote host and back.
> > 
> > The connection is terminated by sending a ThunderboltIP logout packet
> > over the configuration channel. We do this when the network interface is
> > brought down by user or the driver is unloaded.
> > 
> > Signed-off-by: Amir Levy <amir.jer.levy@intel.com>
> > Signed-off-by: Michael Jamet <michael.jamet@intel.com>
> > Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> > Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
> > ---
> >  Documentation/admin-guide/thunderbolt.rst |   24 +
> >  drivers/thunderbolt/Kconfig               |   12 +
> >  drivers/thunderbolt/Makefile              |    3 +
> >  drivers/thunderbolt/net.c                 | 1392 +++++++++++++++++++++++++++++
> >  4 files changed, 1431 insertions(+)
> >  create mode 100644 drivers/thunderbolt/net.c
> 
> Hi Mika
> 
> Could this be renamed to driver/net/thunderbolt.c?

I pondered between drivers/thunderbolt/net.c and
drivers/net/thunderbolt.c and then decided to go with the former because
it follows drivers/firewire/net.c and kind of makes it easier for user
to enabled.

But no problem moving it into drivers/net if that's what networking
people prefer.

> At minimum, it needs a MAINTAINER entry pointing to netdev, so patches
> get reviewed by netdev people. However, since the driver seems to be a
> lot more netdev than thunderbolt, placing it in driver/net could be
> better.

OK.

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#1734717 — Re: [PATCH 06/16] thunderbolt: Add support for XDomain discovery protocol

On Mon, Sep 18, 2017 at 06:30:39PM +0300, Mika Westerberg wrote:
> +What:		/sys/bus/thunderbolt/devices/<xdomain>.<service>/key
> +Date:		Dec 2017
> +KernelVersion:	4.14

I forgot to update these to 4.15. I'll fix them in v2.

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