[PATCH v4 0/7] Fix timeout clock used by hardware data timeout

[PATCH v4 0/7] Fix timeout clock used by hardware data timeout

[Sowjanya Komatineni]

Tegra210/Tegra186/Tegra194 has incorrectly enabled
SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK from the beginning of their support.

Tegra210 and later SDMMC hardware default uses sdmmc_legacy_tm (TMCLK)
all the time for hardware data timeout instead of SDCLK and this TMCLK
need to be kept enabled by Tegra sdmmc driver.

This series includes patches to fix this for Tegra210/Tegra186/Tegra194.

These patches need to be manually backported for 4.9, 4.14 and 4.19.

Will send patches to backport separately once these patches are ack'd.

Delta between patch versions:
[v4]:	Include additional dt-binding patch

[v3]:	Same as v2 with fixes tag

[v2]:	Includes minor fix
	- Patch-0006: parentheses around operand of '!'

Sowjanya Komatineni (7):
  sdhci: tegra: Remove SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK for Tegra210
  sdhci: tegra: Remove SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK for Tegra186
  dt-bindings: mmc: tegra: Add tmclk for Tegra210 and later
  arm64: tegra: Add missing timeout clock to Tegra210 SDMMC
  arm64: tegra: Add missing timeout clock to Tegra186 SDMMC nodes
  arm64: tegra: Add missing timeout clock to Tegra194 SDMMC nodes
  sdhci: tegra: Add missing TMCLK for data timeout

 .../bindings/mmc/nvidia,tegra20-sdhci.txt          | 23 +++++++++++-
 arch/arm64/boot/dts/nvidia/tegra186.dtsi           | 20 ++++++----
 arch/arm64/boot/dts/nvidia/tegra194.dtsi           | 15 +++++---
 arch/arm64/boot/dts/nvidia/tegra210.dtsi           | 20 ++++++----
 drivers/mmc/host/sdhci-tegra.c                     | 43 +++++++++++++++++++++-
 5 files changed, 96 insertions(+), 25 deletions(-)

-- 
2.7.4

[PATCH v4 1/7] sdhci: tegra: Remove SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK for Tegra210

[Sowjanya Komatineni]

commit b5a84ecf025a ("mmc: tegra: Add Tegra210 support")

SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK is set for Tegra210 from the
beginning of Tegra210 support in the driver.

Tegra210 SDMMC hardware by default uses timeout clock (TMCLK)
instead of SDCLK and this quirk should not be set.

So, this patch remove this quirk for Tegra210.

Fixes: b5a84ecf025a ("mmc: tegra: Add Tegra210 support")
Cc: stable <stable@vger.kernel.org> # 5.4
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/mmc/host/sdhci-tegra.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
index 0a3f9d0..2be3511 100644
--- a/drivers/mmc/host/sdhci-tegra.c
+++ b/drivers/mmc/host/sdhci-tegra.c
@@ -1418,7 +1418,6 @@ static const struct sdhci_ops tegra210_sdhci_ops = {
 
 static const struct sdhci_pltfm_data sdhci_tegra210_pdata = {
 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
-		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
 		  SDHCI_QUIRK_NO_HISPD_BIT |
 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
-- 
2.7.4

[PATCH v4 2/7] sdhci: tegra: Remove SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK for Tegra186

[Sowjanya Komatineni]

commit 4346b7c7941d ("mmc: tegra: Add Tegra186 support")

SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK is set for Tegra186 from the
beginning of its support in driver.

Tegra186 SDMMC hardware by default uses timeout clock (TMCLK) instead
of SDCLK and this quirk should not be set.

So, this patch remove this quirk for Tegra186.

Fixes: 4346b7c7941d ("mmc: tegra: Add Tegra186 support")
Cc: stable <stable@vger.kernel.org> # 5.4
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/mmc/host/sdhci-tegra.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
index 2be3511..31ed321 100644
--- a/drivers/mmc/host/sdhci-tegra.c
+++ b/drivers/mmc/host/sdhci-tegra.c
@@ -1455,7 +1455,6 @@ static const struct sdhci_ops tegra186_sdhci_ops = {
 
 static const struct sdhci_pltfm_data sdhci_tegra186_pdata = {
 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
-		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
 		  SDHCI_QUIRK_NO_HISPD_BIT |
 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
-- 
2.7.4

[PATCH v4 3/7] dt-bindings: mmc: tegra: Add tmclk for Tegra210 and later

[Sowjanya Komatineni]

Tegra210 and later uses separate SDMMC_LEGACY_TM clock for data
timeout.

So, this patch adds "tmclk" to Tegra sdhci clock property in the
device tree binding.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 .../bindings/mmc/nvidia,tegra20-sdhci.txt          | 23 +++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt b/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt
index 2cf3aff..9603d05 100644
--- a/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt
+++ b/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt
@@ -17,6 +17,8 @@ Required properties:
   - "nvidia,tegra194-sdhci": for Tegra194
 - clocks : Must contain one entry, for the module clock.
   See ../clocks/clock-bindings.txt for details.
+  Must also contain "tmclk" entry for Tegra210, Tegra186, and Tegra194.
+  Tegra210 and later uses separate SDMMC_LEGACY_TM clock for data timeout.
 - resets : Must contain an entry for each entry in reset-names.
   See ../reset/reset.txt for details.
 - reset-names : Must include the following entries:
@@ -99,7 +101,7 @@ Optional properties for Tegra210, Tegra186 and Tegra194:
 
 Example:
 sdhci@700b0000 {
-	compatible = "nvidia,tegra210-sdhci", "nvidia,tegra124-sdhci";
+	compatible = "nvidia,tegra124-sdhci";
 	reg = <0x0 0x700b0000 0x0 0x200>;
 	interrupts = <GIC_SPI 14 IRQ_TYPE_LEVEL_HIGH>;
 	clocks = <&tegra_car TEGRA210_CLK_SDMMC1>;
@@ -115,3 +117,22 @@ sdhci@700b0000 {
 	nvidia,pad-autocal-pull-down-offset-1v8 = <0x7b>;
 	status = "disabled";
 };
+
+sdhci@700b0000 {
+	compatible = "nvidia,tegra210-sdhci";
+	reg = <0x0 0x700b0000 0x0 0x200>;
+	interrupts = <GIC_SPI 14 IRQ_TYPE_LEVEL_HIGH>;
+	clocks = <&tegra_car TEGRA210_CLK_SDMMC1>,
+		 <&tegra_car TEGRA210_CLK_SDMMC_LEGACY>;
+	clock-names = "sdhci", "tmclk";
+	resets = <&tegra_car 14>;
+	reset-names = "sdhci";
+	pinctrl-names = "sdmmc-3v3", "sdmmc-1v8";
+	pinctrl-0 = <&sdmmc1_3v3>;
+	pinctrl-1 = <&sdmmc1_1v8>;
+	nvidia,pad-autocal-pull-up-offset-3v3 = <0x00>;
+	nvidia,pad-autocal-pull-down-offset-3v3 = <0x7d>;
+	nvidia,pad-autocal-pull-up-offset-1v8 = <0x7b>;
+	nvidia,pad-autocal-pull-down-offset-1v8 = <0x7b>;
+	status = "disabled";
+};
-- 
2.7.4

Re: [PATCH v4 3/7] dt-bindings: mmc: tegra: Add tmclk for Tegra210 and later

[Jon Hunter]

On 24/08/2020 20:15, Sowjanya Komatineni wrote:
> Tegra210 and later uses separate SDMMC_LEGACY_TM clock for data
> timeout.
> 
> So, this patch adds "tmclk" to Tegra sdhci clock property in the
> device tree binding.
> 
> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
> ---
>  .../bindings/mmc/nvidia,tegra20-sdhci.txt          | 23 +++++++++++++++++++++-
>  1 file changed, 22 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt b/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt
> index 2cf3aff..9603d05 100644
> --- a/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt
> +++ b/Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt
> @@ -17,6 +17,8 @@ Required properties:
>    - "nvidia,tegra194-sdhci": for Tegra194
>  - clocks : Must contain one entry, for the module clock.
>    See ../clocks/clock-bindings.txt for details.
> +  Must also contain "tmclk" entry for Tegra210, Tegra186, and Tegra194.
> +  Tegra210 and later uses separate SDMMC_LEGACY_TM clock for data timeout.

Maybe we should make this a bit clearer ...

- clocks : For Tegra210, Tegra186 and Tegra194 must contain two entries;
           one for the module clock and one for the timeout clock. For
           all other Tegra devices, must contain a single entry for the
           module clock. See ../clocks/clock-bindings.txt for details.
- clock-names: For Tegra210, Tegra186 and Tegra194 must contain the
               strings 'sdhci' and 'tmclk' to represent the module and
               timeout clocks, respectively. For all other Tegra devices
               must contain the string 'sdhci' to represent the module
               clock.

Cheers
Jon

-- 
nvpublic

[PATCH v4 4/7] arm64: tegra: Add missing timeout clock to Tegra210 SDMMC

[Sowjanya Komatineni]

commit 742af7e7a0a1 ("arm64: tegra: Add Tegra210 support")

Tegra210 uses separate SDMMC_LEGACY_TM clock for data timeout and
this clock is not enabled currently which is not recommended.

Tegra SDMMC advertises 12Mhz as timeout clock frequency in host
capability register.

So, this clock should be kept enabled by SDMMC driver.

Fixes: 742af7e7a0a1 ("arm64: tegra: Add Tegra210 support")
Cc: stable <stable@vger.kernel.org> # 5.4
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 arch/arm64/boot/dts/nvidia/tegra210.dtsi | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/arch/arm64/boot/dts/nvidia/tegra210.dtsi b/arch/arm64/boot/dts/nvidia/tegra210.dtsi
index 829f786..8cca216 100644
--- a/arch/arm64/boot/dts/nvidia/tegra210.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra210.dtsi
@@ -1194,8 +1194,9 @@
 		compatible = "nvidia,tegra210-sdhci";
 		reg = <0x0 0x700b0000 0x0 0x200>;
 		interrupts = <GIC_SPI 14 IRQ_TYPE_LEVEL_HIGH>;
-		clocks = <&tegra_car TEGRA210_CLK_SDMMC1>;
-		clock-names = "sdhci";
+		clocks = <&tegra_car TEGRA210_CLK_SDMMC1>,
+			 <&tegra_car TEGRA210_CLK_SDMMC_LEGACY>;
+		clock-names = "sdhci", "tmclk";
 		resets = <&tegra_car 14>;
 		reset-names = "sdhci";
 		pinctrl-names = "sdmmc-3v3", "sdmmc-1v8",
@@ -1222,8 +1223,9 @@
 		compatible = "nvidia,tegra210-sdhci";
 		reg = <0x0 0x700b0200 0x0 0x200>;
 		interrupts = <GIC_SPI 15 IRQ_TYPE_LEVEL_HIGH>;
-		clocks = <&tegra_car TEGRA210_CLK_SDMMC2>;
-		clock-names = "sdhci";
+		clocks = <&tegra_car TEGRA210_CLK_SDMMC2>,
+			 <&tegra_car TEGRA210_CLK_SDMMC_LEGACY>;
+		clock-names = "sdhci", "tmclk";
 		resets = <&tegra_car 9>;
 		reset-names = "sdhci";
 		pinctrl-names = "sdmmc-1v8-drv";
@@ -1239,8 +1241,9 @@
 		compatible = "nvidia,tegra210-sdhci";
 		reg = <0x0 0x700b0400 0x0 0x200>;
 		interrupts = <GIC_SPI 19 IRQ_TYPE_LEVEL_HIGH>;
-		clocks = <&tegra_car TEGRA210_CLK_SDMMC3>;
-		clock-names = "sdhci";
+		clocks = <&tegra_car TEGRA210_CLK_SDMMC3>,
+			 <&tegra_car TEGRA210_CLK_SDMMC_LEGACY>;
+		clock-names = "sdhci", "tmclk";
 		resets = <&tegra_car 69>;
 		reset-names = "sdhci";
 		pinctrl-names = "sdmmc-3v3", "sdmmc-1v8",
@@ -1262,8 +1265,9 @@
 		compatible = "nvidia,tegra210-sdhci";
 		reg = <0x0 0x700b0600 0x0 0x200>;
 		interrupts = <GIC_SPI 31 IRQ_TYPE_LEVEL_HIGH>;
-		clocks = <&tegra_car TEGRA210_CLK_SDMMC4>;
-		clock-names = "sdhci";
+		clocks = <&tegra_car TEGRA210_CLK_SDMMC4>,
+			 <&tegra_car TEGRA210_CLK_SDMMC_LEGACY>;
+		clock-names = "sdhci", "tmclk";
 		resets = <&tegra_car 15>;
 		reset-names = "sdhci";
 		pinctrl-names = "sdmmc-3v3-drv", "sdmmc-1v8-drv";
-- 
2.7.4

[PATCH v4 5/7] arm64: tegra: Add missing timeout clock to Tegra186 SDMMC nodes

[Sowjanya Komatineni]

commit 39cb62cb8973 ("arm64: tegra: Add Tegra186 support")

Tegra186 uses separate SDMMC_LEGACY_TM clock for data timeout and
this clock is not enabled currently which is not recommended.

Tegra186 SDMMC advertises 12Mhz as timeout clock frequency in host
capability register and uses it by default.

So, this clock should be kept enabled by the SDMMC driver.

Fixes: 39cb62cb8973 ("arm64: tegra: Add Tegra186 support")
Cc: stable <stable@vger.kernel.org> # 5.4
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 arch/arm64/boot/dts/nvidia/tegra186.dtsi | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/arch/arm64/boot/dts/nvidia/tegra186.dtsi b/arch/arm64/boot/dts/nvidia/tegra186.dtsi
index 34d249d..8eb61dd 100644
--- a/arch/arm64/boot/dts/nvidia/tegra186.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra186.dtsi
@@ -337,8 +337,9 @@
 		compatible = "nvidia,tegra186-sdhci";
 		reg = <0x0 0x03400000 0x0 0x10000>;
 		interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>;
-		clocks = <&bpmp TEGRA186_CLK_SDMMC1>;
-		clock-names = "sdhci";
+		clocks = <&bpmp TEGRA186_CLK_SDMMC1>,
+			 <&bpmp TEGRA186_CLK_SDMMC_LEGACY_TM>;
+		clock-names = "sdhci", "tmclk";
 		resets = <&bpmp TEGRA186_RESET_SDMMC1>;
 		reset-names = "sdhci";
 		interconnects = <&mc TEGRA186_MEMORY_CLIENT_SDMMCRA &emc>,
@@ -366,8 +367,9 @@
 		compatible = "nvidia,tegra186-sdhci";
 		reg = <0x0 0x03420000 0x0 0x10000>;
 		interrupts = <GIC_SPI 63 IRQ_TYPE_LEVEL_HIGH>;
-		clocks = <&bpmp TEGRA186_CLK_SDMMC2>;
-		clock-names = "sdhci";
+		clocks = <&bpmp TEGRA186_CLK_SDMMC2>,
+			 <&bpmp TEGRA186_CLK_SDMMC_LEGACY_TM>;
+		clock-names = "sdhci", "tmclk";
 		resets = <&bpmp TEGRA186_RESET_SDMMC2>;
 		reset-names = "sdhci";
 		interconnects = <&mc TEGRA186_MEMORY_CLIENT_SDMMCRAA &emc>,
@@ -390,8 +392,9 @@
 		compatible = "nvidia,tegra186-sdhci";
 		reg = <0x0 0x03440000 0x0 0x10000>;
 		interrupts = <GIC_SPI 64 IRQ_TYPE_LEVEL_HIGH>;
-		clocks = <&bpmp TEGRA186_CLK_SDMMC3>;
-		clock-names = "sdhci";
+		clocks = <&bpmp TEGRA186_CLK_SDMMC3>,
+			 <&bpmp TEGRA186_CLK_SDMMC_LEGACY_TM>;
+		clock-names = "sdhci", "tmclk";
 		resets = <&bpmp TEGRA186_RESET_SDMMC3>;
 		reset-names = "sdhci";
 		interconnects = <&mc TEGRA186_MEMORY_CLIENT_SDMMCR &emc>,
@@ -416,8 +419,9 @@
 		compatible = "nvidia,tegra186-sdhci";
 		reg = <0x0 0x03460000 0x0 0x10000>;
 		interrupts = <GIC_SPI 65 IRQ_TYPE_LEVEL_HIGH>;
-		clocks = <&bpmp TEGRA186_CLK_SDMMC4>;
-		clock-names = "sdhci";
+		clocks = <&bpmp TEGRA186_CLK_SDMMC4>,
+			 <&bpmp TEGRA186_CLK_SDMMC_LEGACY_TM>;
+		clock-names = "sdhci", "tmclk";
 		assigned-clocks = <&bpmp TEGRA186_CLK_SDMMC4>,
 				  <&bpmp TEGRA186_CLK_PLLC4_VCO>;
 		assigned-clock-parents = <&bpmp TEGRA186_CLK_PLLC4_VCO>;
-- 
2.7.4

[PATCH v4 6/7] arm64: tegra: Add missing timeout clock to Tegra194 SDMMC nodes

[Sowjanya Komatineni]

commit 5425fb15d8ee ("arm64: tegra: Add Tegra194 chip device tree")

Tegra194 uses separate SDMMC_LEGACY_TM clock for data timeout and
this clock is not enabled currently which is not recommended.

Tegra194 SDMMC advertises 12Mhz as timeout clock frequency in host
capability register.

So, this clock should be kept enabled by SDMMC driver.

Fixes: 5425fb15d8ee ("arm64: tegra: Add Tegra194 chip device tree")
Cc: stable <stable@vger.kernel.org> # 5.4
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 arch/arm64/boot/dts/nvidia/tegra194.dtsi | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/boot/dts/nvidia/tegra194.dtsi b/arch/arm64/boot/dts/nvidia/tegra194.dtsi
index 48160f4..ca5cb6a 100644
--- a/arch/arm64/boot/dts/nvidia/tegra194.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra194.dtsi
@@ -460,8 +460,9 @@
 			compatible = "nvidia,tegra194-sdhci";
 			reg = <0x03400000 0x10000>;
 			interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>;
-			clocks = <&bpmp TEGRA194_CLK_SDMMC1>;
-			clock-names = "sdhci";
+			clocks = <&bpmp TEGRA194_CLK_SDMMC1>,
+				 <&bpmp TEGRA194_CLK_SDMMC_LEGACY_TM>;
+			clock-names = "sdhci", "tmclk";
 			resets = <&bpmp TEGRA194_RESET_SDMMC1>;
 			reset-names = "sdhci";
 			interconnects = <&mc TEGRA194_MEMORY_CLIENT_SDMMCRA &emc>,
@@ -485,8 +486,9 @@
 			compatible = "nvidia,tegra194-sdhci";
 			reg = <0x03440000 0x10000>;
 			interrupts = <GIC_SPI 64 IRQ_TYPE_LEVEL_HIGH>;
-			clocks = <&bpmp TEGRA194_CLK_SDMMC3>;
-			clock-names = "sdhci";
+			clocks = <&bpmp TEGRA194_CLK_SDMMC3>,
+				 <&bpmp TEGRA194_CLK_SDMMC_LEGACY_TM>;
+			clock-names = "sdhci", "tmclk";
 			resets = <&bpmp TEGRA194_RESET_SDMMC3>;
 			reset-names = "sdhci";
 			interconnects = <&mc TEGRA194_MEMORY_CLIENT_SDMMCR &emc>,
@@ -511,8 +513,9 @@
 			compatible = "nvidia,tegra194-sdhci";
 			reg = <0x03460000 0x10000>;
 			interrupts = <GIC_SPI 65 IRQ_TYPE_LEVEL_HIGH>;
-			clocks = <&bpmp TEGRA194_CLK_SDMMC4>;
-			clock-names = "sdhci";
+			clocks = <&bpmp TEGRA194_CLK_SDMMC4>,
+				 <&bpmp TEGRA194_CLK_SDMMC_LEGACY_TM>;
+			clock-names = "sdhci", "tmclk";
 			assigned-clocks = <&bpmp TEGRA194_CLK_SDMMC4>,
 					  <&bpmp TEGRA194_CLK_PLLC4>;
 			assigned-clock-parents =
-- 
2.7.4

[PATCH v4 7/7] sdhci: tegra: Add missing TMCLK for data timeout

[Sowjanya Komatineni]

commit b5a84ecf025a ("mmc: tegra: Add Tegra210 support")

Tegra210 and later has a separate sdmmc_legacy_tm (TMCLK) used by Tegra
SDMMC hawdware for data timeout to achive better timeout than using
SDCLK and using TMCLK is recommended.

USE_TMCLK_FOR_DATA_TIMEOUT bit in Tegra SDMMC register
SDHCI_TEGRA_VENDOR_SYS_SW_CTRL can be used to choose either TMCLK or
SDCLK for data timeout.

Default USE_TMCLK_FOR_DATA_TIMEOUT bit is set to 1 and TMCLK is used
for data timeout by Tegra SDMMC hardware and having TMCLK not enabled
is not recommended.

So, this patch fixes it.

Fixes: b5a84ecf025a ("mmc: tegra: Add Tegra210 support")
Cc: stable <stable@vger.kernel.org> # 5.4
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/mmc/host/sdhci-tegra.c | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
index 31ed321..c0b9405 100644
--- a/drivers/mmc/host/sdhci-tegra.c
+++ b/drivers/mmc/host/sdhci-tegra.c
@@ -140,6 +140,7 @@ struct sdhci_tegra_autocal_offsets {
 struct sdhci_tegra {
 	const struct sdhci_tegra_soc_data *soc_data;
 	struct gpio_desc *power_gpio;
+	struct clk *tmclk;
 	bool ddr_signaling;
 	bool pad_calib_required;
 	bool pad_control_available;
@@ -1611,6 +1612,44 @@ static int sdhci_tegra_probe(struct platform_device *pdev)
 		goto err_power_req;
 	}
 
+	/*
+	 * Tegra210 has a separate SDMMC_LEGACY_TM clock used for host
+	 * timeout clock and SW can choose TMCLK or SDCLK for hardware
+	 * data timeout through the bit USE_TMCLK_FOR_DATA_TIMEOUT of
+	 * the register SDHCI_TEGRA_VENDOR_SYS_SW_CTRL.
+	 *
+	 * USE_TMCLK_FOR_DATA_TIMEOUT bit default is set to 1 and SDMMC uses
+	 * 12Mhz TMCLK which is advertised in host capability register.
+	 * With TMCLK of 12Mhz provides maximum data timeout period that can
+	 * be achieved is 11s better than using SDCLK for data timeout.
+	 *
+	 * So, TMCLK is set to 12Mhz and kept enabled all the time on SoC's
+	 * supporting SDR104 mode and when not using SDCLK for data timeout.
+	 */
+
+	if ((soc_data->nvquirks & NVQUIRK_ENABLE_SDR104) &&
+	    !(soc_data->pdata->quirks & SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK)) {
+		clk = devm_clk_get(&pdev->dev, "tmclk");
+		if (IS_ERR(clk)) {
+			rc = PTR_ERR(clk);
+			if (rc == -EPROBE_DEFER)
+				goto err_power_req;
+
+			dev_warn(&pdev->dev, "failed to get tmclk: %d\n", rc);
+			clk = NULL;
+		}
+
+		clk_set_rate(clk, 12000000);
+		rc = clk_prepare_enable(clk);
+		if (rc) {
+			dev_err(&pdev->dev,
+				"failed to enable tmclk: %d\n", rc);
+			goto err_power_req;
+		}
+
+		tegra_host->tmclk = clk;
+	}
+
 	clk = devm_clk_get(mmc_dev(host->mmc), NULL);
 	if (IS_ERR(clk)) {
 		rc = PTR_ERR(clk);
@@ -1654,6 +1693,7 @@ static int sdhci_tegra_probe(struct platform_device *pdev)
 err_rst_get:
 	clk_disable_unprepare(pltfm_host->clk);
 err_clk_get:
+	clk_disable_unprepare(tegra_host->tmclk);
 err_power_req:
 err_parse_dt:
 	sdhci_pltfm_free(pdev);
@@ -1671,6 +1711,7 @@ static int sdhci_tegra_remove(struct platform_device *pdev)
 	reset_control_assert(tegra_host->rst);
 	usleep_range(2000, 4000);
 	clk_disable_unprepare(pltfm_host->clk);
+	clk_disable_unprepare(tegra_host->tmclk);
 
 	sdhci_pltfm_free(pdev);
 
-- 
2.7.4

Re: [PATCH v4 7/7] sdhci: tegra: Add missing TMCLK for data timeout

[Jon Hunter]

On 24/08/2020 20:15, Sowjanya Komatineni wrote:
> commit b5a84ecf025a ("mmc: tegra: Add Tegra210 support")
> 
> Tegra210 and later has a separate sdmmc_legacy_tm (TMCLK) used by Tegra
> SDMMC hawdware for data timeout to achive better timeout than using
> SDCLK and using TMCLK is recommended.
> 
> USE_TMCLK_FOR_DATA_TIMEOUT bit in Tegra SDMMC register
> SDHCI_TEGRA_VENDOR_SYS_SW_CTRL can be used to choose either TMCLK or
> SDCLK for data timeout.
> 
> Default USE_TMCLK_FOR_DATA_TIMEOUT bit is set to 1 and TMCLK is used
> for data timeout by Tegra SDMMC hardware and having TMCLK not enabled
> is not recommended.
> 
> So, this patch fixes it.
> 
> Fixes: b5a84ecf025a ("mmc: tegra: Add Tegra210 support")
> Cc: stable <stable@vger.kernel.org> # 5.4
> Tested-by: Jon Hunter <jonathanh@nvidia.com>
> Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
> Acked-by: Adrian Hunter <adrian.hunter@intel.com>
> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
> ---
>  drivers/mmc/host/sdhci-tegra.c | 41 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 41 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
> index 31ed321..c0b9405 100644
> --- a/drivers/mmc/host/sdhci-tegra.c
> +++ b/drivers/mmc/host/sdhci-tegra.c
> @@ -140,6 +140,7 @@ struct sdhci_tegra_autocal_offsets {
>  struct sdhci_tegra {
>  	const struct sdhci_tegra_soc_data *soc_data;
>  	struct gpio_desc *power_gpio;
> +	struct clk *tmclk;
>  	bool ddr_signaling;
>  	bool pad_calib_required;
>  	bool pad_control_available;
> @@ -1611,6 +1612,44 @@ static int sdhci_tegra_probe(struct platform_device *pdev)
>  		goto err_power_req;
>  	}
>  
> +	/*
> +	 * Tegra210 has a separate SDMMC_LEGACY_TM clock used for host
> +	 * timeout clock and SW can choose TMCLK or SDCLK for hardware
> +	 * data timeout through the bit USE_TMCLK_FOR_DATA_TIMEOUT of
> +	 * the register SDHCI_TEGRA_VENDOR_SYS_SW_CTRL.
> +	 *
> +	 * USE_TMCLK_FOR_DATA_TIMEOUT bit default is set to 1 and SDMMC uses
> +	 * 12Mhz TMCLK which is advertised in host capability register.
> +	 * With TMCLK of 12Mhz provides maximum data timeout period that can
> +	 * be achieved is 11s better than using SDCLK for data timeout.
> +	 *
> +	 * So, TMCLK is set to 12Mhz and kept enabled all the time on SoC's
> +	 * supporting SDR104 mode and when not using SDCLK for data timeout.
> +	 */
> +
> +	if ((soc_data->nvquirks & NVQUIRK_ENABLE_SDR104) &&
> +	    !(soc_data->pdata->quirks & SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK)) {
> +		clk = devm_clk_get(&pdev->dev, "tmclk");
> +		if (IS_ERR(clk)) {
> +			rc = PTR_ERR(clk);
> +			if (rc == -EPROBE_DEFER)
> +				goto err_power_req;
> +
> +			dev_warn(&pdev->dev, "failed to get tmclk: %d\n", rc);
> +			clk = NULL;
> +		}
> +
> +		clk_set_rate(clk, 12000000);
> +		rc = clk_prepare_enable(clk);
> +		if (rc) {
> +			dev_err(&pdev->dev,
> +				"failed to enable tmclk: %d\n", rc);
> +			goto err_power_req;
> +		}
> +
> +		tegra_host->tmclk = clk;
> +	}
> +
>  	clk = devm_clk_get(mmc_dev(host->mmc), NULL);


One thing that I just thought of is that now we may have two clocks,
shouldn't we use the name, 'sdhci', for requesting the above clock as well?

Unfortunately, the name 'sdhci' has not been populated for all Tegra
devices until recently and so we may need to check if there are one of
two clocks populated. If there is only one, then maybe we fall back to
the above.

Cheers
Jon

-- 
nvpublic