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Groups > linux.kernel > #1416694 > unrolled thread
| Started by | Douglas Anderson <dianders@chromium.org> |
|---|---|
| First post | 2016-06-08 00:50 +0200 |
| Last post | 2016-06-08 00:50 +0200 |
| Articles | 13 — 3 participants |
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[PATCH 0/11] Changes to support 150 MHz eMMC on rk3399 Douglas Anderson <dianders@chromium.org> - 2016-06-08 00:50 +0200
[PATCH 06/11] Documentation: mmc: sdhci-of-arasan: Add ability to export card clock Douglas Anderson <dianders@chromium.org> - 2016-06-08 00:50 +0200
Re: [PATCH 06/11] Documentation: mmc: sdhci-of-arasan: Add ability to export card clock Rob Herring <robh@kernel.org> - 2016-06-08 22:20 +0200
Re: [PATCH 06/11] Documentation: mmc: sdhci-of-arasan: Add ability to export card clock Doug Anderson <dianders@chromium.org> - 2016-06-08 23:00 +0200
Re: [PATCH 06/11] Documentation: mmc: sdhci-of-arasan: Add ability to export card clock Rob Herring <robh@kernel.org> - 2016-06-10 15:20 +0200
[PATCH 05/11] arm64: dts: rockchip: Add soc-ctl-syscon to sdhci for rk3399 Douglas Anderson <dianders@chromium.org> - 2016-06-08 00:50 +0200
[PATCH 01/11] phy: rockchip-emmc: Increase lock time allowance Douglas Anderson <dianders@chromium.org> - 2016-06-08 00:50 +0200
[PATCH 10/11] phy: rockchip-emmc: Minor code cleanup in rockchip_emmc_phy_power_off() Douglas Anderson <dianders@chromium.org> - 2016-06-08 00:50 +0200
[PATCH 09/11] phy: rockchip-emmc: Set phyctrl_frqsel based on card clock Douglas Anderson <dianders@chromium.org> - 2016-06-08 00:50 +0200
[PATCH 04/11] mmc: sdhci-of-arasan: Properly set corecfg_baseclkfreq on rk3399 Douglas Anderson <dianders@chromium.org> - 2016-06-08 00:50 +0200
[PATCH 08/11] Documentation: phy: Let the rockchip eMMC PHY get an exported card clock Douglas Anderson <dianders@chromium.org> - 2016-06-08 00:50 +0200
Re: [PATCH 08/11] Documentation: phy: Let the rockchip eMMC PHY get an exported card clock Rob Herring <robh@kernel.org> - 2016-06-10 15:40 +0200
[PATCH 07/11] mmc: sdhci-of-arasan: Add ability to export card clock Douglas Anderson <dianders@chromium.org> - 2016-06-08 00:50 +0200
| From | Douglas Anderson <dianders@chromium.org> |
|---|---|
| Date | 2016-06-08 00:50 +0200 |
| Subject | [PATCH 0/11] Changes to support 150 MHz eMMC on rk3399 |
| Message-ID | <rHxYR-aA-5@gated-at.bofh.it> |
The theme of this series of patches is to try to allow running the eMMC
at 150 MHz on the rk3399 SoC, though the changes should still be correct
and have merit on their own. The motivation for running at 150 MHz is
that doing so improves signal integrity and (with some eMMC devices)
doesn't affect throughput.
These patches have been structured to keep things as separate as
possible, but nevertheless there are still some dependencies between
patches. It probably makes the most sense for all of the non-device
tree patches to go through a single tree. If others agree, perhaps the
most sane would be to get Acks from PHY maintainers and then to land the
patches in the MMC tree. Device tree patches should be able to be
landed separately and the worst what would happen is a warning in the
kernel log if you have the code without the device tree.
The code patches are based on Ulf's mmc-next, then 4 patches that are
outstanding / ready to land. Specifically:
- https://patchwork.kernel.org/patch/9086501/
phy: rockchip-emmc: give DLL some extra time to be ready
- https://patchwork.kernel.org/patch/9093681/
phy: rockchip-emmc: configure frequency range and drive impedance
- https://patchwork.kernel.org/patch/9086511/
phy: rockchip-emmc: configure default output tap delay
- https://patchwork.kernel.org/patch/9086531/
phy: rockchip-emmc: reindent the register definitions
The device tree patches are based on Heiko's v4.8-armsoc/dts64.
If requested, I could repost my series with the outstanding code patches
or I could try folding those patches into mine. Since those patches
aren't in 4.7-rc1 presumably they would also make sense to take through
the MMC tree if others agree.
Douglas Anderson (11):
phy: rockchip-emmc: Increase lock time allowance
mmc: sdhci-of-arasan: Always power the PHY off/on when clock changes
Documentation: mmc: sdhci-of-arasan: Add soc-ctl-syscon for corecfg
regs
mmc: sdhci-of-arasan: Properly set corecfg_baseclkfreq on rk3399
arm64: dts: rockchip: Add soc-ctl-syscon to sdhci for rk3399
Documentation: mmc: sdhci-of-arasan: Add ability to export card clock
mmc: sdhci-of-arasan: Add ability to export card clock
Documentation: phy: Let the rockchip eMMC PHY get an exported card
clock
phy: rockchip-emmc: Set phyctrl_frqsel based on card clock
phy: rockchip-emmc: Minor code cleanup in
rockchip_emmc_phy_power_off()
arm64: dts: rockchip: Provide emmcclk to PHY for rk3399
.../devicetree/bindings/mmc/arasan,sdhci.txt | 35 ++-
.../devicetree/bindings/phy/rockchip-emmc-phy.txt | 7 +
arch/arm64/boot/dts/rockchip/rk3399.dtsi | 5 +
drivers/mmc/host/sdhci-of-arasan.c | 333 +++++++++++++++++++--
drivers/phy/phy-rockchip-emmc.c | 107 +++++--
5 files changed, 427 insertions(+), 60 deletions(-)
--
2.8.0.rc3.226.g39d4020
[toc] | [next] | [standalone]
| From | Douglas Anderson <dianders@chromium.org> |
|---|---|
| Date | 2016-06-08 00:50 +0200 |
| Subject | [PATCH 06/11] Documentation: mmc: sdhci-of-arasan: Add ability to export card clock |
| Message-ID | <rHxYR-aA-15@gated-at.bofh.it> |
| In reply to | #1416694 |
Some SD/eMMC PHYs (like the PHY from Arasan that is designed to work
with arasan,sdhci-5.1) need to know the card clock in order to function
properly. Let's expose this clock using a standard device tree
mechanism so that the PHY can get access to and query the card clock.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
Documentation/devicetree/bindings/mmc/arasan,sdhci.txt | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt b/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
index b67e623ca1ff..074d03e630ec 100644
--- a/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
+++ b/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
@@ -30,6 +30,12 @@ Optional Properties:
- arasan,soc-ctl-syscon: A phandle to a syscon device (see ../mfd/syscon.txt)
used to access core corecfg registers. Offsets of registers in this
syscon are determined based on the main compatible string for the device.
+ - clock-output-names: If specified, this will be the name of the card clock
+ which will be exposed by this device. Required if #clock-cells is
+ specified.
+ - #clock-cells: If specified this should be the value <0>. With this property
+ in place we will export a clock representing the Card Clock. This clock
+ is expected to be consumed by our PHY. You must also specify
Example:
sdhci@e0100000 {
@@ -61,7 +67,9 @@ Example:
arasan,soc-ctl-syscon = <&grf>;
assigned-clocks = <&cru SCLK_EMMC>;
assigned-clock-rates = <200000000>;
+ clock-output-names = "emmc_cardclock";
phys = <&emmc_phy>;
phy-names = "phy_arasan";
+ #clock-cells = <0>;
status = "disabled";
};
--
2.8.0.rc3.226.g39d4020
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| From | Rob Herring <robh@kernel.org> |
|---|---|
| Date | 2016-06-08 22:20 +0200 |
| Subject | Re: [PATCH 06/11] Documentation: mmc: sdhci-of-arasan: Add ability to export card clock |
| Message-ID | <rHS7f-4Ox-17@gated-at.bofh.it> |
| In reply to | #1416695 |
On Tue, Jun 07, 2016 at 03:44:39PM -0700, Douglas Anderson wrote:
> Some SD/eMMC PHYs (like the PHY from Arasan that is designed to work
> with arasan,sdhci-5.1) need to know the card clock in order to function
> properly. Let's expose this clock using a standard device tree
> mechanism so that the PHY can get access to and query the card clock.
Need to know the clock freq or need the clock? The former doesn't need
to be in DT.
>
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> ---
> Documentation/devicetree/bindings/mmc/arasan,sdhci.txt | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt b/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
> index b67e623ca1ff..074d03e630ec 100644
> --- a/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
> +++ b/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
> @@ -30,6 +30,12 @@ Optional Properties:
> - arasan,soc-ctl-syscon: A phandle to a syscon device (see ../mfd/syscon.txt)
> used to access core corecfg registers. Offsets of registers in this
> syscon are determined based on the main compatible string for the device.
> + - clock-output-names: If specified, this will be the name of the card clock
> + which will be exposed by this device. Required if #clock-cells is
> + specified.
> + - #clock-cells: If specified this should be the value <0>. With this property
> + in place we will export a clock representing the Card Clock. This clock
> + is expected to be consumed by our PHY. You must also specify
>
> Example:
> sdhci@e0100000 {
> @@ -61,7 +67,9 @@ Example:
> arasan,soc-ctl-syscon = <&grf>;
> assigned-clocks = <&cru SCLK_EMMC>;
> assigned-clock-rates = <200000000>;
> + clock-output-names = "emmc_cardclock";
> phys = <&emmc_phy>;
> phy-names = "phy_arasan";
> + #clock-cells = <0>;
> status = "disabled";
> };
> --
> 2.8.0.rc3.226.g39d4020
>
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| From | Doug Anderson <dianders@chromium.org> |
|---|---|
| Date | 2016-06-08 23:00 +0200 |
| Subject | Re: [PATCH 06/11] Documentation: mmc: sdhci-of-arasan: Add ability to export card clock |
| Message-ID | <rHSJX-53j-15@gated-at.bofh.it> |
| In reply to | #1417847 |
Rob, On Wed, Jun 8, 2016 at 1:19 PM, Rob Herring <robh@kernel.org> wrote: > On Tue, Jun 07, 2016 at 03:44:39PM -0700, Douglas Anderson wrote: >> Some SD/eMMC PHYs (like the PHY from Arasan that is designed to work >> with arasan,sdhci-5.1) need to know the card clock in order to function >> properly. Let's expose this clock using a standard device tree >> mechanism so that the PHY can get access to and query the card clock. > > Need to know the clock freq or need the clock? The former doesn't need > to be in DT. The PHY needs to know the card clock frequency. This clock clock frequency is known nowhere else in the system except the SDHCI driver since the SDHCI component takes its input clock and applies some dividers to get the card clock. In silicon, the SDHCI component and the PHY are separate and there is a physical clock signal going from the SDHCI component to the PHY component, so modeling this as a clock in in the device tree seems sane, doesn't it? -Doug
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| From | Rob Herring <robh@kernel.org> |
|---|---|
| Date | 2016-06-10 15:20 +0200 |
| Subject | Re: [PATCH 06/11] Documentation: mmc: sdhci-of-arasan: Add ability to export card clock |
| Message-ID | <rIuvT-527-11@gated-at.bofh.it> |
| In reply to | #1417867 |
On Wed, Jun 08, 2016 at 01:52:20PM -0700, Doug Anderson wrote: > Rob, > > On Wed, Jun 8, 2016 at 1:19 PM, Rob Herring <robh@kernel.org> wrote: > > On Tue, Jun 07, 2016 at 03:44:39PM -0700, Douglas Anderson wrote: > >> Some SD/eMMC PHYs (like the PHY from Arasan that is designed to work > >> with arasan,sdhci-5.1) need to know the card clock in order to function > >> properly. Let's expose this clock using a standard device tree > >> mechanism so that the PHY can get access to and query the card clock. > > > > Need to know the clock freq or need the clock? The former doesn't need > > to be in DT. > > The PHY needs to know the card clock frequency. This clock clock > frequency is known nowhere else in the system except the SDHCI driver > since the SDHCI component takes its input clock and applies some > dividers to get the card clock. In silicon, the SDHCI component and > the PHY are separate and there is a physical clock signal going from > the SDHCI component to the PHY component, so modeling this as a clock > in in the device tree seems sane, doesn't it? Yes, please just re-word it to make it clear there is a connection. With that, Acked-by: Rob Herring <robh@kernel.org>
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| From | Douglas Anderson <dianders@chromium.org> |
|---|---|
| Date | 2016-06-08 00:50 +0200 |
| Subject | [PATCH 05/11] arm64: dts: rockchip: Add soc-ctl-syscon to sdhci for rk3399 |
| Message-ID | <rHxYR-aA-19@gated-at.bofh.it> |
| In reply to | #1416694 |
On rk3399 we'd like to be able to properly set corecfg registers in the Arasan SDHCI component. Specify the syscon to enable that. Signed-off-by: Douglas Anderson <dianders@chromium.org> --- arch/arm64/boot/dts/rockchip/rk3399.dtsi | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/dts/rockchip/rk3399.dtsi index a4383f359264..1b57e92e0093 100644 --- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi +++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi @@ -220,6 +220,7 @@ compatible = "rockchip,rk3399-sdhci-5.1", "arasan,sdhci-5.1"; reg = <0x0 0xfe330000 0x0 0x10000>; interrupts = <GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>; + arasan,soc-ctl-syscon = <&grf>; assigned-clocks = <&cru SCLK_EMMC>; assigned-clock-rates = <200000000>; clocks = <&cru SCLK_EMMC>, <&cru ACLK_EMMC>; -- 2.8.0.rc3.226.g39d4020
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| From | Douglas Anderson <dianders@chromium.org> |
|---|---|
| Date | 2016-06-08 00:50 +0200 |
| Subject | [PATCH 01/11] phy: rockchip-emmc: Increase lock time allowance |
| Message-ID | <rHxYR-aA-25@gated-at.bofh.it> |
| In reply to | #1416694 |
Previous PHY code waited a fixed amount of time for the DLL to lock at
power on time. Unfortunately, the time for the DLL to lock is actually
a bit more dynamic and can be longer if the card clock is slower.
Instead of waiting a fixed 30 us, let's now dynamically wait until the
lock bit gets set. We'll wait up to 10 ms which should be OK even if
the card clock is at the super slow 100 kHz.
On its own, this change makes the PHY power on code a little more
robust. Before this change the PHY was relying on the eMMC code to make
sure the PHY was only powered on when the card clock was set to at least
50 MHz before, though this reliance wasn't documented anywhere.
This change will be even more useful in future changes where we actually
need to be able to wait for a DLL lock at slower clock speeds.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
drivers/phy/phy-rockchip-emmc.c | 27 +++++++++++++++++++--------
1 file changed, 19 insertions(+), 8 deletions(-)
diff --git a/drivers/phy/phy-rockchip-emmc.c b/drivers/phy/phy-rockchip-emmc.c
index a69f53630e67..8336053aea5c 100644
--- a/drivers/phy/phy-rockchip-emmc.c
+++ b/drivers/phy/phy-rockchip-emmc.c
@@ -85,6 +85,7 @@ static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
{
unsigned int caldone;
unsigned int dllrdy;
+ unsigned long timeout;
/*
* Keep phyctrl_pdb and phyctrl_endll low to allow
@@ -137,15 +138,25 @@ static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
PHYCTRL_ENDLL_MASK,
PHYCTRL_ENDLL_SHIFT));
/*
- * After enable analog DLL circuits, we need an extra 10.2us
- * for dll to be ready for work. But according to testing, we
- * find some chips need more than 25us.
+ * After enabling analog DLL circuits docs say that we need 10.2 us if
+ * our source clock is at 50 MHz and that lock time scales linearly
+ * with clock speed. If we are powering on the PHY and the card clock
+ * is super slow (like 100 kHZ) this could take as long as 5.1 ms.
+ * Hopefully we won't be running at 100 kHz, but we should still make
+ * sure we wait long enough.
*/
- udelay(30);
- regmap_read(rk_phy->reg_base,
- rk_phy->reg_offset + GRF_EMMCPHY_STATUS,
- &dllrdy);
- dllrdy = (dllrdy >> PHYCTRL_DLLRDY_SHIFT) & PHYCTRL_DLLRDY_MASK;
+ timeout = jiffies + msecs_to_jiffies(10);
+ do {
+ udelay(1);
+
+ regmap_read(rk_phy->reg_base,
+ rk_phy->reg_offset + GRF_EMMCPHY_STATUS,
+ &dllrdy);
+ dllrdy = (dllrdy >> PHYCTRL_DLLRDY_SHIFT) & PHYCTRL_DLLRDY_MASK;
+ if (dllrdy == PHYCTRL_DLLRDY_DONE)
+ break;
+ } while (!time_after(jiffies, timeout));
+
if (dllrdy != PHYCTRL_DLLRDY_DONE) {
pr_err("rockchip_emmc_phy_power: dllrdy timeout.\n");
return -ETIMEDOUT;
--
2.8.0.rc3.226.g39d4020
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| From | Douglas Anderson <dianders@chromium.org> |
|---|---|
| Date | 2016-06-08 00:50 +0200 |
| Subject | [PATCH 10/11] phy: rockchip-emmc: Minor code cleanup in rockchip_emmc_phy_power_off() |
| Message-ID | <rHxYS-aA-33@gated-at.bofh.it> |
| In reply to | #1416694 |
There's no reason to store the return value of rockchip_emmc_phy_power()
in a variable nor to check it. Just return it.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
drivers/phy/phy-rockchip-emmc.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/drivers/phy/phy-rockchip-emmc.c b/drivers/phy/phy-rockchip-emmc.c
index 0fce7359d468..188e4c387ba8 100644
--- a/drivers/phy/phy-rockchip-emmc.c
+++ b/drivers/phy/phy-rockchip-emmc.c
@@ -227,8 +227,6 @@ static int rockchip_emmc_phy_power_off(struct phy *phy)
static int rockchip_emmc_phy_power_on(struct phy *phy)
{
struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
- int ret = 0;
-
/* Drive impedance: 50 Ohm */
regmap_write(rk_phy->reg_base,
@@ -252,11 +250,7 @@ static int rockchip_emmc_phy_power_on(struct phy *phy)
PHYCTRL_OTAPDLYSEL_SHIFT));
/* Power up emmc phy analog blocks */
- ret = rockchip_emmc_phy_power(phy, PHYCTRL_PDB_PWR_ON);
- if (ret)
- return ret;
-
- return 0;
+ return rockchip_emmc_phy_power(phy, PHYCTRL_PDB_PWR_ON);
}
static const struct phy_ops ops = {
--
2.8.0.rc3.226.g39d4020
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| From | Douglas Anderson <dianders@chromium.org> |
|---|---|
| Date | 2016-06-08 00:50 +0200 |
| Subject | [PATCH 09/11] phy: rockchip-emmc: Set phyctrl_frqsel based on card clock |
| Message-ID | <rHxYS-aA-35@gated-at.bofh.it> |
| In reply to | #1416694 |
The "phyctrl_frqsel" is described in the Arasan datasheet [1] as "the
frequency range of DLL operation". Although the Rockchip variant of
this PHY has different ranges than the reference Arasan PHY it appears
as if the functionality is similar. We should set this phyctrl field
properly.
Note: as per Rockchip engineers, apparently the "phyctrl_frqsel" is
actually only useful in HS200 / HS400 modes even though the DLL itself
it used for some purposes in all modes. See the discussion in the
earlier change in this series: ("mmc: sdhci-of-arasan: Always power the
PHY off/on when clock changes"). In any case, it shouldn't hurt to set
this always.
Note that this change should allow boards to run at HS200 / HS400 speed
modes while running at 100 MHz or 150 MHz. In fact, running HS400 at
150 MHz (giving 300 MB/s) is the main motivation of this series, since
performance is still good but signal integrity problems are less
prevelant at 150 MHz.
[1]: https://arasan.com/wp-content/media/eMMC-5-1-Total-Solution_Rev-1-3.pdf
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
drivers/phy/phy-rockchip-emmc.c | 74 +++++++++++++++++++++++++++++++----------
1 file changed, 57 insertions(+), 17 deletions(-)
diff --git a/drivers/phy/phy-rockchip-emmc.c b/drivers/phy/phy-rockchip-emmc.c
index 8336053aea5c..0fce7359d468 100644
--- a/drivers/phy/phy-rockchip-emmc.c
+++ b/drivers/phy/phy-rockchip-emmc.c
@@ -14,6 +14,7 @@
* GNU General Public License for more details.
*/
+#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
@@ -78,16 +79,61 @@
struct rockchip_emmc_phy {
unsigned int reg_offset;
struct regmap *reg_base;
+ struct clk *emmcclk;
};
-static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
- bool on_off)
+static int rockchip_emmc_phy_power(struct phy *phy, bool on_off)
{
+ struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
unsigned int caldone;
unsigned int dllrdy;
+ unsigned int freqsel = PHYCTRL_FREQSEL_200M;
unsigned long timeout;
/*
+ * We purposely get the clock here and not in probe to avoid the
+ * circular dependency problem. We expect:
+ * - PHY driver to probe
+ * - USB driver to start probe
+ * - USB driver to register it's clock
+ * - USB driver to get the PHY
+ * - USB driver to power on the PHY
+ */
+ if (!rk_phy->emmcclk) {
+ rk_phy->emmcclk = devm_clk_get(&phy->dev, "emmcclk");
+
+ /* Don't expect defer at this point; try next time */
+ if (PTR_ERR(rk_phy->emmcclk) == -EPROBE_DEFER) {
+ dev_warn(&phy->dev, "Unexpected emmcclk defer\n");
+ rk_phy->emmcclk = NULL;
+ }
+ }
+
+ if (!IS_ERR_OR_NULL(rk_phy->emmcclk)) {
+ unsigned long rate = clk_get_rate(rk_phy->emmcclk);
+
+ switch (rate) {
+ case 0 ... 74999999:
+ /* Nominal 50 MHz */
+ freqsel = PHYCTRL_FREQSEL_50M;
+ break;
+ case 75000000 ... 124999999:
+ /* Nominal 100 MHz */
+ freqsel = PHYCTRL_FREQSEL_100M;
+ break;
+ case 125000000 ... 174999999:
+ /* Nominal 150 MHz */
+ freqsel = PHYCTRL_FREQSEL_150M;
+ break;
+ default:
+ if (rate > 200000000)
+ dev_warn(&phy->dev, "Unsupported rate: %lu\n",
+ rate);
+ break;
+ };
+ }
+
+ /*
* Keep phyctrl_pdb and phyctrl_endll low to allow
* initialization of CALIO state M/C DFFs
*/
@@ -132,6 +178,13 @@ static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
return -ETIMEDOUT;
}
+ /* Set the frequency of the DLL operation */
+ regmap_write(rk_phy->reg_base,
+ rk_phy->reg_offset + GRF_EMMCPHY_CON0,
+ HIWORD_UPDATE(freqsel, PHYCTRL_FREQSEL_MASK,
+ PHYCTRL_FREQSEL_SHIFT));
+
+ /* Turn on the DLL */
regmap_write(rk_phy->reg_base,
rk_phy->reg_offset + GRF_EMMCPHY_CON6,
HIWORD_UPDATE(PHYCTRL_ENDLL_ENABLE,
@@ -167,15 +220,8 @@ static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
static int rockchip_emmc_phy_power_off(struct phy *phy)
{
- struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
- int ret = 0;
-
/* Power down emmc phy analog blocks */
- ret = rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_OFF);
- if (ret)
- return ret;
-
- return 0;
+ return rockchip_emmc_phy_power(phy, PHYCTRL_PDB_PWR_OFF);
}
static int rockchip_emmc_phy_power_on(struct phy *phy)
@@ -183,12 +229,6 @@ static int rockchip_emmc_phy_power_on(struct phy *phy)
struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
int ret = 0;
- /* DLL operation: 200 MHz */
- regmap_write(rk_phy->reg_base,
- rk_phy->reg_offset + GRF_EMMCPHY_CON0,
- HIWORD_UPDATE(PHYCTRL_FREQSEL_200M,
- PHYCTRL_FREQSEL_MASK,
- PHYCTRL_FREQSEL_SHIFT));
/* Drive impedance: 50 Ohm */
regmap_write(rk_phy->reg_base,
@@ -212,7 +252,7 @@ static int rockchip_emmc_phy_power_on(struct phy *phy)
PHYCTRL_OTAPDLYSEL_SHIFT));
/* Power up emmc phy analog blocks */
- ret = rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_ON);
+ ret = rockchip_emmc_phy_power(phy, PHYCTRL_PDB_PWR_ON);
if (ret)
return ret;
--
2.8.0.rc3.226.g39d4020
[toc] | [prev] | [next] | [standalone]
| From | Douglas Anderson <dianders@chromium.org> |
|---|---|
| Date | 2016-06-08 00:50 +0200 |
| Subject | [PATCH 04/11] mmc: sdhci-of-arasan: Properly set corecfg_baseclkfreq on rk3399 |
| Message-ID | <rHxYR-aA-23@gated-at.bofh.it> |
| In reply to | #1416694 |
In the the earlier change in this series ("Documentation: mmc:
sdhci-of-arasan: Add soc-ctl-syscon for corecfg regs") we can see the
mechansim for specifying a syscon to properly set corecfg registers in
sdhci-of-arasan. Now let's use this mechanism to properly set
corecfg_baseclkfreq on rk3399.
From [1] the corecfg_baseclkfreq is supposed to be set to:
Base Clock Frequency for SD Clock.
This is the frequency of the xin_clk.
This is a relatively easy thing to do. Note that we assume that xin_clk
is not dynamic and we can check the clock at probe time. If any real
devices have a dynamic xin_clk future patches could register for
notifiers for the clock.
At the moment, setting corecfg_baseclkfreq is only supported for rk3399
since we need a specific map for each implementation. The code is
written in a generic way that should make this easy to extend to other
SoCs. Note that a specific compatible string for rk3399 is already in
use and so we add that to the table to match rk3399.
[1]: https://arasan.com/wp-content/media/eMMC-5-1-Total-Solution_Rev-1-3.pdf
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
drivers/mmc/host/sdhci-of-arasan.c | 189 ++++++++++++++++++++++++++++++++++---
1 file changed, 178 insertions(+), 11 deletions(-)
diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 3ff1711077c2..859ea1b21215 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -22,6 +22,8 @@
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/phy/phy.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
#include "sdhci-pltfm.h"
#define SDHCI_ARASAN_CLK_CTRL_OFFSET 0x2c
@@ -32,18 +34,115 @@
#define CLK_CTRL_TIMEOUT_MASK (0xf << CLK_CTRL_TIMEOUT_SHIFT)
#define CLK_CTRL_TIMEOUT_MIN_EXP 13
+/*
+ * On some SoCs the syscon area has a feature where the upper 16-bits of
+ * each 32-bit register act as a write mask for the lower 16-bits. This allows
+ * atomic updates of the register without locking. This macro is used on SoCs
+ * that have that feature.
+ */
+#define HIWORD_UPDATE(val, mask, shift) \
+ ((val) << (shift) | (mask) << ((shift) + 16))
+
+/**
+ * struct sdhci_arasan_soc_ctl_field - Field used in sdhci_arasan_soc_ctl_map
+ *
+ * @reg: Offset within the syscon of the register containing this field
+ * @width: Number of bits for this field
+ * @shift: Bit offset within @reg of this field (or -1 if not avail)
+ */
+struct sdhci_arasan_soc_ctl_field {
+ u32 reg;
+ u16 width;
+ s16 shift;
+};
+
+/**
+ * struct sdhci_arasan_soc_ctl_map - Map in syscon to corecfg registers
+ *
+ * It's up to the licensee of the Arsan IP block to make these available
+ * somewhere if needed. Presumably these will be scattered somewhere that's
+ * accessible via the syscon API.
+ *
+ * @baseclkfreq: Where to find corecfg_baseclkfreq
+ * @hiword_update: If true, use HIWORD_UPDATE to access the syscon
+ */
+struct sdhci_arasan_soc_ctl_map {
+ struct sdhci_arasan_soc_ctl_field baseclkfreq;
+ bool hiword_update;
+};
+
/**
* struct sdhci_arasan_data
- * @clk_ahb: Pointer to the AHB clock
- * @phy: Pointer to the generic phy
- * @phy_on: True if the PHY is turned on.
+ * @clk_ahb: Pointer to the AHB clock
+ * @phy: Pointer to the generic phy
+ * @phy_on: True if the PHY is turned on.
+ * @soc_ctl_base: Pointer to regmap for syscon for soc_ctl registers.
+ * @soc_ctl_map: Map to get offsets into soc_ctl registers.
*/
struct sdhci_arasan_data {
struct clk *clk_ahb;
struct phy *phy;
bool phy_on;
+
+ struct regmap *soc_ctl_base;
+ const struct sdhci_arasan_soc_ctl_map *soc_ctl_map;
+};
+
+static const struct sdhci_arasan_soc_ctl_map rk3399_soc_ctl_map = {
+ .baseclkfreq = { .reg = 0xf000, .width = 8, .shift = 8 },
+ .hiword_update = true,
};
+/**
+ * sdhci_arasan_syscon_write - Write to a field in soc_ctl registers
+ *
+ * This function allows writing to fields in sdhci_arasan_soc_ctl_map.
+ * Note that if a field is specified as not available (shift < 0) then
+ * this function will silently return an error code. It will be noisy
+ * and print errors for any other (unexpected) errors.
+ *
+ * @host: The sdhci_host
+ * @fld: The field to write to
+ * @val: The value to write
+ */
+static int sdhci_arasan_syscon_write(struct sdhci_host *host,
+ const struct sdhci_arasan_soc_ctl_field *fld,
+ u32 val)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+ struct regmap *soc_ctl_base = sdhci_arasan->soc_ctl_base;
+ u32 reg = fld->reg;
+ u16 width = fld->width;
+ s16 shift = fld->shift;
+ int ret;
+
+ /*
+ * Silently return errors for shift < 0 so caller doesn't have
+ * to check for fields which are optional. For fields that
+ * are required then caller needs to do something special
+ * anyway.
+ */
+ if (shift < 0)
+ return -EINVAL;
+
+ if (sdhci_arasan->soc_ctl_map->hiword_update)
+ ret = regmap_write(soc_ctl_base, reg,
+ HIWORD_UPDATE(val, GENMASK(width, 0),
+ shift));
+ else
+ ret = regmap_update_bits(soc_ctl_base, reg,
+ GENMASK(shift + width, shift),
+ val << shift);
+
+ /* Yell about (unexpected) regmap errors */
+ if (ret)
+ pr_warn("%s: Regmap write fail: %d\n",
+ mmc_hostname(host->mmc), ret);
+
+ return ret;
+}
+
static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host)
{
u32 div;
@@ -191,9 +290,66 @@ static int sdhci_arasan_resume(struct device *dev)
static SIMPLE_DEV_PM_OPS(sdhci_arasan_dev_pm_ops, sdhci_arasan_suspend,
sdhci_arasan_resume);
+static const struct of_device_id sdhci_arasan_of_match[] = {
+ /* SoC-specific compatible strings w/ soc_ctl_map */
+ {
+ .compatible = "rockchip,rk3399-sdhci-5.1",
+ .data = &rk3399_soc_ctl_map,
+ },
+
+ /* Generic compatible below here */
+ { .compatible = "arasan,sdhci-8.9a" },
+ { .compatible = "arasan,sdhci-5.1" },
+ { .compatible = "arasan,sdhci-4.9a" },
+
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
+
+/**
+ * sdhci_arasan_update_baseclkfreq - Set corecfg_baseclkfreq
+ *
+ * The corecfg_baseclkfreq is supposed to contain the MHz of clk_xin. This
+ * function can be used to make that happen.
+ *
+ * NOTES:
+ * - Many existing devices don't seem to do this and work fine. To keep
+ * compatibility for old hardware where the device tree doesn't provide a
+ * register map, this function is a noop if a soc_ctl_map hasn't been provided
+ * for this platform.
+ * - It's assumed that clk_xin is not dynamic and that we use the SDHCI divider
+ * to achieve lower clock rates. That means that this function is called once
+ * at probe time and never called again.
+ *
+ * @host: The sdhci_host
+ */
+static void sdhci_arasan_update_baseclkfreq(struct sdhci_host *host)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+ const struct sdhci_arasan_soc_ctl_map *soc_ctl_map =
+ sdhci_arasan->soc_ctl_map;
+ u32 mhz = DIV_ROUND_CLOSEST(clk_get_rate(pltfm_host->clk), 1000000);
+
+ /* Having a map is optional */
+ if (!soc_ctl_map)
+ return;
+
+ /* If we have a map, we expect to have a syscon */
+ if (!sdhci_arasan->soc_ctl_base) {
+ pr_warn("%s: Have regmap, but no soc-ctl-syscon\n",
+ mmc_hostname(host->mmc));
+ return;
+ }
+
+ sdhci_arasan_syscon_write(host, &soc_ctl_map->baseclkfreq, mhz);
+}
+
static int sdhci_arasan_probe(struct platform_device *pdev)
{
int ret;
+ const struct of_device_id *match;
+ struct device_node *node;
struct clk *clk_xin;
struct sdhci_host *host;
struct sdhci_pltfm_host *pltfm_host;
@@ -207,6 +363,23 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
pltfm_host = sdhci_priv(host);
sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+ match = of_match_node(sdhci_arasan_of_match, pdev->dev.of_node);
+ sdhci_arasan->soc_ctl_map = match->data;
+
+ node = of_parse_phandle(pdev->dev.of_node, "arasan,soc-ctl-syscon", 0);
+ if (node) {
+ sdhci_arasan->soc_ctl_base = syscon_node_to_regmap(node);
+ of_node_put(node);
+
+ if (IS_ERR(sdhci_arasan->soc_ctl_base)) {
+ ret = PTR_ERR(sdhci_arasan->soc_ctl_base);
+ if (ret != -EPROBE_DEFER)
+ dev_err(&pdev->dev, "Can't get syscon: %d\n",
+ ret);
+ goto err_pltfm_free;
+ }
+ }
+
sdhci_arasan->clk_ahb = devm_clk_get(&pdev->dev, "clk_ahb");
if (IS_ERR(sdhci_arasan->clk_ahb)) {
dev_err(&pdev->dev, "clk_ahb clock not found.\n");
@@ -236,6 +409,8 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
sdhci_get_of_property(pdev);
pltfm_host->clk = clk_xin;
+ sdhci_arasan_update_baseclkfreq(host);
+
ret = mmc_of_parse(host->mmc);
if (ret) {
dev_err(&pdev->dev, "parsing dt failed (%u)\n", ret);
@@ -301,14 +476,6 @@ static int sdhci_arasan_remove(struct platform_device *pdev)
return ret;
}
-static const struct of_device_id sdhci_arasan_of_match[] = {
- { .compatible = "arasan,sdhci-8.9a" },
- { .compatible = "arasan,sdhci-5.1" },
- { .compatible = "arasan,sdhci-4.9a" },
- { }
-};
-MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
-
static struct platform_driver sdhci_arasan_driver = {
.driver = {
.name = "sdhci-arasan",
--
2.8.0.rc3.226.g39d4020
[toc] | [prev] | [next] | [standalone]
| From | Douglas Anderson <dianders@chromium.org> |
|---|---|
| Date | 2016-06-08 00:50 +0200 |
| Subject | [PATCH 08/11] Documentation: phy: Let the rockchip eMMC PHY get an exported card clock |
| Message-ID | <rHxYR-aA-27@gated-at.bofh.it> |
| In reply to | #1416694 |
As of an earlier change in this series ("Documentation: mmc:
sdhci-of-arasan: Add ability to export card clock") the SDHCI driver
used on Rockchip SoCs can now expose its clock. Let's now specify that
the PHY can use it.
Letting the PHY get access to this clock means it can adjust
phyctrl_frqsel field appropriately. Although the Rockchip PHY appears
slightly different than the reference Arasan one, you can see that the
Arasan datasheet [1] had it defined as:
Select the frequency range of DLL operation:
3b'000 => 200MHz to 170 MHz
3b'001 => 170MHz to 140 MHz
3b'010 => 140MHz to 110 MHz
3b'011 => 110MHz to 80MHz
3b'100 => 80MHz to 50 MHz
3b'101 => 275Mhz to 250MHz
3b'110 => 250MHz to 225MHz
3b'111 => 225MHz to 200MHz
On the Rockchip version of the PHY we have less granularity but the idea
is the same.
[1]: https://arasan.com/wp-content/media/eMMC-5-1-Total-Solution_Rev-1-3.pdf
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
index 555cb0f40690..fd118b071e5e 100644
--- a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
+++ b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
@@ -7,6 +7,11 @@ Required properties:
- reg: PHY register address offset and length in "general
register files"
+Optional clocks (see ../clock/clock-bindings.txt), specified by name:
+ - emmcclk: The card clock exported by the SDHCI driver. Although this is
+ listed as optional (because most boards can get basic functionality
+ without having access to it), it is strongly suggested.
+
Example:
@@ -20,6 +25,8 @@ grf: syscon@ff770000 {
emmcphy: phy@f780 {
compatible = "rockchip,rk3399-emmc-phy";
reg = <0xf780 0x20>;
+ clocks = <&sdhci>;
+ clock-names = "emmcclk";
#phy-cells = <0>;
};
};
--
2.8.0.rc3.226.g39d4020
[toc] | [prev] | [next] | [standalone]
| From | Rob Herring <robh@kernel.org> |
|---|---|
| Date | 2016-06-10 15:40 +0200 |
| Subject | Re: [PATCH 08/11] Documentation: phy: Let the rockchip eMMC PHY get an exported card clock |
| Message-ID | <rIuPg-58O-21@gated-at.bofh.it> |
| In reply to | #1416702 |
On Tue, Jun 07, 2016 at 03:44:41PM -0700, Douglas Anderson wrote:
> As of an earlier change in this series ("Documentation: mmc:
> sdhci-of-arasan: Add ability to export card clock") the SDHCI driver
> used on Rockchip SoCs can now expose its clock. Let's now specify that
> the PHY can use it.
>
> Letting the PHY get access to this clock means it can adjust
> phyctrl_frqsel field appropriately. Although the Rockchip PHY appears
> slightly different than the reference Arasan one, you can see that the
> Arasan datasheet [1] had it defined as:
> Select the frequency range of DLL operation:
> 3b'000 => 200MHz to 170 MHz
> 3b'001 => 170MHz to 140 MHz
> 3b'010 => 140MHz to 110 MHz
> 3b'011 => 110MHz to 80MHz
> 3b'100 => 80MHz to 50 MHz
> 3b'101 => 275Mhz to 250MHz
> 3b'110 => 250MHz to 225MHz
> 3b'111 => 225MHz to 200MHz
>
> On the Rockchip version of the PHY we have less granularity but the idea
> is the same.
>
> [1]: https://arasan.com/wp-content/media/eMMC-5-1-Total-Solution_Rev-1-3.pdf
>
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> ---
> Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
> index 555cb0f40690..fd118b071e5e 100644
> --- a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
> +++ b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
> @@ -7,6 +7,11 @@ Required properties:
> - reg: PHY register address offset and length in "general
> register files"
>
> +Optional clocks (see ../clock/clock-bindings.txt), specified by name:
> + - emmcclk: The card clock exported by the SDHCI driver. Although this is
This reads like emmcclk is the property. You need to list out clocks and
clock-names.
> + listed as optional (because most boards can get basic functionality
> + without having access to it), it is strongly suggested.
> +
> Example:
>
>
> @@ -20,6 +25,8 @@ grf: syscon@ff770000 {
> emmcphy: phy@f780 {
> compatible = "rockchip,rk3399-emmc-phy";
> reg = <0xf780 0x20>;
> + clocks = <&sdhci>;
> + clock-names = "emmcclk";
> #phy-cells = <0>;
> };
> };
> --
> 2.8.0.rc3.226.g39d4020
>
[toc] | [prev] | [next] | [standalone]
| From | Douglas Anderson <dianders@chromium.org> |
|---|---|
| Date | 2016-06-08 00:50 +0200 |
| Subject | [PATCH 07/11] mmc: sdhci-of-arasan: Add ability to export card clock |
| Message-ID | <rHxYS-aA-31@gated-at.bofh.it> |
| In reply to | #1416694 |
Some SD/eMMC PHYs (like the PHY from Arasan that is designed to work
with arasan,sdhci-5.1) need to know the card clock in order to function
properly. Let's add the ability to expose this clock. Any PHY that
needs to know the clock rate can add a reference and query the clock
rate.
At the moment we register a CLK_GET_RATE_NOCACHE clock that simply
allows querying the clock. This allows us to be less intrusive with
regards to the main SDHCI driver, which has complex logic for adjusting
the SD clock. Right now we always fully power cycle the PHY when the
clock changes and that gives the PHY a good chance to query our clock.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
drivers/mmc/host/sdhci-of-arasan.c | 125 ++++++++++++++++++++++++++++++++++++-
1 file changed, 122 insertions(+), 3 deletions(-)
diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 859ea1b21215..25852e4fd1b6 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -19,6 +19,7 @@
* your option) any later version.
*/
+#include <linux/clk-provider.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/phy/phy.h>
@@ -73,17 +74,24 @@ struct sdhci_arasan_soc_ctl_map {
/**
* struct sdhci_arasan_data
+ * @host: Pointer to the main SDHCI host structure.
* @clk_ahb: Pointer to the AHB clock
* @phy: Pointer to the generic phy
* @phy_on: True if the PHY is turned on.
+ * @sdcardclk_hw: Struct for the clock we might provide to a PHY.
+ * @sdcardclk: Pointer to normal 'struct clock' for sdcardclk_hw.
* @soc_ctl_base: Pointer to regmap for syscon for soc_ctl registers.
* @soc_ctl_map: Map to get offsets into soc_ctl registers.
*/
struct sdhci_arasan_data {
+ struct sdhci_host *host;
struct clk *clk_ahb;
struct phy *phy;
bool phy_on;
+ struct clk_hw sdcardclk_hw;
+ struct clk *sdcardclk;
+
struct regmap *soc_ctl_base;
const struct sdhci_arasan_soc_ctl_map *soc_ctl_map;
};
@@ -307,6 +315,31 @@ static const struct of_device_id sdhci_arasan_of_match[] = {
MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
/**
+ * sdhci_arasan_sdcardclk_recalc_rate - Return the card clock rate
+ *
+ * Return the current actual rate of the SD card clock. This can be used
+ * to communicate with out PHY.
+ *
+ * @hw: Pointer to the hardware clock structure.
+ * @parent_rate The parent rate (should be rate of clk_xin).
+ * Returns the card clock rate.
+ */
+static unsigned long sdhci_arasan_sdcardclk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+
+{
+ struct sdhci_arasan_data *sdhci_arasan =
+ container_of(hw, struct sdhci_arasan_data, sdcardclk_hw);
+ struct sdhci_host *host = sdhci_arasan->host;
+
+ return host->mmc->actual_clock;
+}
+
+static const struct clk_ops arasan_sdcardclk_ops = {
+ .recalc_rate = sdhci_arasan_sdcardclk_recalc_rate,
+};
+
+/**
* sdhci_arasan_update_baseclkfreq - Set corecfg_baseclkfreq
*
* The corecfg_baseclkfreq is supposed to contain the MHz of clk_xin. This
@@ -345,6 +378,83 @@ static void sdhci_arasan_update_baseclkfreq(struct sdhci_host *host)
sdhci_arasan_syscon_write(host, &soc_ctl_map->baseclkfreq, mhz);
}
+/**
+ * sdhci_arasan_register_sdclk - Register the sdclk for a PHY to use
+ *
+ * Some PHY devices need to know what the actual card clock is. In order for
+ * them to find out, we'll provide a clock through the common clock framework
+ * for them to query.
+ *
+ * Note: without seriously re-architecting SDHCI's clock code and testing on
+ * all platforms, there's no way to create a totally beautiful clock here
+ * with all clock ops implemented. Instead, we'll just create a clock that can
+ * be queried and set the CLK_GET_RATE_NOCACHE attribute to tell common clock
+ * framework that we're doing things behind its back. This should be sufficient
+ * to create nice clean device tree bindings and later (if needed) we can try
+ * re-architecting SDHCI if we see some benefit to it.
+ *
+ * @sdhci_arasan: Our private data structure.
+ * @clk_xin: Pointer to the functional clock
+ * @dev: Pointer to our struct device.
+ * Returns 0 on success and error value on error
+ */
+static int sdhci_arasan_register_sdclk(struct sdhci_arasan_data *sdhci_arasan,
+ struct clk *clk_xin,
+ struct device *dev)
+{
+ struct device_node *np = dev->of_node;
+ struct clk_init_data sdcardclk_init;
+ const char *parent_clk_name;
+ int ret;
+
+ /* Providing a clock to the PHY is optional; no error if missing */
+ if (!of_find_property(np, "#clock-cells", NULL))
+ return 0;
+
+ ret = of_property_read_string_index(np, "clock-output-names", 0,
+ &sdcardclk_init.name);
+ if (ret) {
+ dev_err(dev, "DT has #clock-cells but no clock-output-names\n");
+ return ret;
+ }
+
+ parent_clk_name = __clk_get_name(clk_xin);
+ sdcardclk_init.parent_names = &parent_clk_name;
+ sdcardclk_init.num_parents = 1;
+ sdcardclk_init.flags = CLK_GET_RATE_NOCACHE;
+ sdcardclk_init.ops = &arasan_sdcardclk_ops;
+
+ sdhci_arasan->sdcardclk_hw.init = &sdcardclk_init;
+ sdhci_arasan->sdcardclk =
+ devm_clk_register(dev, &sdhci_arasan->sdcardclk_hw);
+ sdhci_arasan->sdcardclk_hw.init = NULL;
+
+ ret = of_clk_add_provider(np, of_clk_src_simple_get,
+ sdhci_arasan->sdcardclk);
+ if (ret)
+ dev_err(dev, "Failed to add clock provider\n");
+
+ return ret;
+}
+
+/**
+ * sdhci_arasan_unregister_sdclk - Undoes sdhci_arasan_register_sdclk()
+ *
+ * Should be called any time we're exiting and sdhci_arasan_register_sdclk()
+ * returned success.
+ *
+ * @dev: Pointer to our struct device.
+ */
+static void sdhci_arasan_unregister_sdclk(struct device *dev)
+{
+ struct device_node *np = dev->of_node;
+
+ if (!of_find_property(np, "#clock-cells", NULL))
+ return;
+
+ of_clk_del_provider(dev->of_node);
+}
+
static int sdhci_arasan_probe(struct platform_device *pdev)
{
int ret;
@@ -362,6 +472,7 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
pltfm_host = sdhci_priv(host);
sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+ sdhci_arasan->host = host;
match = of_match_node(sdhci_arasan_of_match, pdev->dev.of_node);
sdhci_arasan->soc_ctl_map = match->data;
@@ -411,10 +522,14 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
sdhci_arasan_update_baseclkfreq(host);
+ ret = sdhci_arasan_register_sdclk(sdhci_arasan, clk_xin, &pdev->dev);
+ if (ret)
+ goto clk_disable_all;
+
ret = mmc_of_parse(host->mmc);
if (ret) {
dev_err(&pdev->dev, "parsing dt failed (%u)\n", ret);
- goto clk_disable_all;
+ goto unreg_clk;
}
sdhci_arasan->phy = ERR_PTR(-ENODEV);
@@ -425,13 +540,13 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
if (IS_ERR(sdhci_arasan->phy)) {
ret = PTR_ERR(sdhci_arasan->phy);
dev_err(&pdev->dev, "No phy for arasan,sdhci-5.1.\n");
- goto clk_disable_all;
+ goto unreg_clk;
}
ret = phy_init(sdhci_arasan->phy);
if (ret < 0) {
dev_err(&pdev->dev, "phy_init err.\n");
- goto clk_disable_all;
+ goto unreg_clk;
}
host->mmc_host_ops.hs400_enhanced_strobe =
@@ -447,6 +562,8 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
err_add_host:
if (!IS_ERR(sdhci_arasan->phy))
phy_exit(sdhci_arasan->phy);
+unreg_clk:
+ sdhci_arasan_unregister_sdclk(&pdev->dev);
clk_disable_all:
clk_disable_unprepare(clk_xin);
clk_dis_ahb:
@@ -469,6 +586,8 @@ static int sdhci_arasan_remove(struct platform_device *pdev)
phy_exit(sdhci_arasan->phy);
}
+ sdhci_arasan_unregister_sdclk(&pdev->dev);
+
ret = sdhci_pltfm_unregister(pdev);
clk_disable_unprepare(clk_ahb);
--
2.8.0.rc3.226.g39d4020
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