Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1668963 > unrolled thread

[PATCH 0/3] change powerup logic for MediaTek PCIe controller

Back to article view | Back to linux.kernel

Contents

  [PATCH 0/3] change powerup logic for MediaTek PCIe controller Ryder Lee <ryder.lee@mediatek.com> - 2017-06-19 12:10 +0200
    [PATCH 1/3] PCI: mediatek: modify controller powerup logic Ryder Lee <ryder.lee@mediatek.com> - 2017-06-19 12:10 +0200

#1668963 — [PATCH 0/3] change powerup logic for MediaTek PCIe controller

Hi Bjorn,

This patch series does some modifications to powerup logic to avoid unbalanced
PM warnings, and turns off host power if no link is detected.

I also make some properties(eg, PHY/reset/..) optional to gain more flexibility
just in case future SoCs don't have it.

Could you also fold this patch series into pci/host-mediatek for v4.13?
Thanks!

Ryder Lee (3):
  PCI: mediatek: modify controller powerup logic
  PCI: mediatek: turn off subsys power if no link up detected
  PCI: mediatek: make some properties optioanl

 drivers/pci/host/pcie-mediatek.c | 110 +++++++++++++++++++++------------------
 1 file changed, 58 insertions(+), 52 deletions(-)

-- 
1.9.1

[toc] | [next] | [standalone]

#1668968 — [PATCH 1/3] PCI: mediatek: modify controller powerup logic

The current powerup logic may lead to unbalanced pm_runtime_enable() if
the earlier probe failed due to -EPROBE_DEFER. Hence we do a little flow
adjustment to avoid that:

Parse standard PCI resources firstly, then check properties for each port,
power on controller finally.

Also, this patch removes unused registers and renames funtions properly.

Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
---
 drivers/pci/host/pcie-mediatek.c | 51 +++++++++++++++++-----------------------
 1 file changed, 21 insertions(+), 30 deletions(-)

diff --git a/drivers/pci/host/pcie-mediatek.c b/drivers/pci/host/pcie-mediatek.c
index 3baafa8..165d82d 100644
--- a/drivers/pci/host/pcie-mediatek.c
+++ b/drivers/pci/host/pcie-mediatek.c
@@ -34,8 +34,6 @@
 
 /* PCIe per port registers */
 #define PCIE_BAR0_SETUP		0x10
-#define PCIE_BAR1_SETUP		0x14
-#define PCIE_BAR0_MEM_BASE	0x18
 #define PCIE_CLASS		0x34
 #define PCIE_LINK_STATUS	0x50
 
@@ -224,7 +222,7 @@ static void mtk_pcie_assert_ports(struct mtk_pcie_port *port)
 	msleep(100);
 }
 
-static int mtk_pcie_enable_ports(struct mtk_pcie_port *port)
+static void mtk_pcie_enable_ports(struct mtk_pcie_port *port)
 {
 	struct device *dev = port->pcie->dev;
 	int err;
@@ -249,7 +247,7 @@ static int mtk_pcie_enable_ports(struct mtk_pcie_port *port)
 	/* if link up, then setup root port configuration space */
 	if (mtk_pcie_link_is_up(port)) {
 		mtk_pcie_configure_rc(port);
-		return 0;
+		return;
 	}
 
 	dev_info(dev, "Port%d link down\n", port->index);
@@ -257,13 +255,13 @@ static int mtk_pcie_enable_ports(struct mtk_pcie_port *port)
 	phy_power_off(port->phy);
 err_phy_on:
 	clk_disable_unprepare(port->sys_ck);
-	mtk_pcie_port_free(port);
 err_sys_clk:
-	return err;
+	mtk_pcie_port_free(port);
+
+	return;
 }
 
 static int mtk_pcie_parse_ports(struct mtk_pcie *pcie,
-				struct mtk_pcie_port **p,
 				struct device_node *node,
 				int index)
 {
@@ -274,12 +272,10 @@ static int mtk_pcie_parse_ports(struct mtk_pcie *pcie,
 	char name[10];
 	int err;
 
-	*p = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
-	if (!*p)
+	port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
+	if (!port)
 		return -ENOMEM;
 
-	port = *p;
-
 	err = of_property_read_u32(node, "num-lanes", &port->lane);
 	if (err) {
 		dev_err(dev, "missing num-lanes property\n");
@@ -323,7 +319,7 @@ static int mtk_pcie_parse_ports(struct mtk_pcie *pcie,
 	return 0;
 }
 
-static int mtk_pcie_handle_shared_resource(struct mtk_pcie *pcie)
+static int mtk_pcie_subsys_powerup(struct mtk_pcie *pcie)
 {
 	struct device *dev = pcie->dev;
 	struct platform_device *pdev = to_platform_device(dev);
@@ -366,20 +362,16 @@ static int mtk_pcie_handle_shared_resource(struct mtk_pcie *pcie)
 	return err;
 }
 
-static int mtk_pcie_parse_and_add_res(struct mtk_pcie *pcie)
+static int mtk_pcie_setup(struct mtk_pcie *pcie)
 {
 	struct device *dev = pcie->dev;
 	struct device_node *node = dev->of_node, *child;
 	struct of_pci_range_parser parser;
 	struct of_pci_range range;
 	struct resource res;
+	struct mtk_pcie_port *port, *tmp;
 	int err;
 
-	/* parse shared resources */
-	err = mtk_pcie_handle_shared_resource(pcie);
-	if (err)
-		return err;
-
 	if (of_pci_range_parser_init(&parser, node)) {
 		dev_err(dev, "missing \"ranges\" property\n");
 		return -EINVAL;
@@ -423,8 +415,7 @@ static int mtk_pcie_parse_and_add_res(struct mtk_pcie *pcie)
 		pcie->busn.flags = IORESOURCE_BUS;
 	}
 
-	for_each_child_of_node(node, child) {
-		struct mtk_pcie_port *port;
+	for_each_available_child_of_node(node, child) {
 		int index;
 
 		err = of_pci_get_devfn(child);
@@ -435,19 +426,19 @@ static int mtk_pcie_parse_and_add_res(struct mtk_pcie *pcie)
 
 		index = PCI_SLOT(err);
 
-		if (!of_device_is_available(child))
-			continue;
-
-		err = mtk_pcie_parse_ports(pcie, &port, child, index);
-		if (err)
-			return err;
-
-		/* enable each port, and then check link status */
-		err = mtk_pcie_enable_ports(port);
+		err = mtk_pcie_parse_ports(pcie, child, index);
 		if (err)
 			return err;
 	}
 
+	err = mtk_pcie_subsys_powerup(pcie);
+	if (err)
+		return err;
+
+	/* enable each port, and then check link status */
+	list_for_each_entry_safe(port, tmp, &pcie->ports, list)
+		mtk_pcie_enable_ports(port);
+
 	return 0;
 }
 
@@ -516,7 +507,7 @@ static int mtk_pcie_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, pcie);
 	INIT_LIST_HEAD(&pcie->ports);
 
-	err = mtk_pcie_parse_and_add_res(pcie);
+	err = mtk_pcie_setup(pcie);
 	if (err)
 		return err;
 
-- 
1.9.1

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web