diff mbox series

[12/14] doc: dt: fsl-imx-esdhc: add auto-cmd23-broken binding

Message ID 1573816606-26779-2-git-send-email-haibo.chen@nxp.com
State Changes Requested, archived
Headers show
Series None | expand

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Commit Message

Bough Chen Nov. 15, 2019, 11:16 a.m. UTC
From: Haibo Chen <haibo.chen@nxp.com>

Add fsl,auto-cmd23-broken binding.

Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
---
 Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Rob Herring (Arm) Dec. 3, 2019, 7:27 p.m. UTC | #1
On Fri, Nov 15, 2019 at 07:16:46PM +0800, haibo.chen@nxp.com wrote:
> From: Haibo Chen <haibo.chen@nxp.com>
> 
> Add fsl,auto-cmd23-broken binding.
> 
> Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
> ---
>  Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt b/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt
> index d50144f5f1d2..a776f418a028 100644
> --- a/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt
> +++ b/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt
> @@ -43,6 +43,14 @@ Optional properties:
>    property allows user to change the delay target for the strobe input read clock.
>    If not use this property, driver default set the delay target to value 7.
>    Only eMMC HS400 mode need to take care of this property.
> +- fsl,auto-cmd23-broken: disable the ACMD23 function of USDHC.
> +  This is required for eMMC on imx6qpdl/imx6sx/imx7d when it use ADMA mode. Because
> +  for these SoC, it do not support the ACMD23 completely, only take the 16 bit block
> +  count from the 0x4 register (BLK_ATT) as argument for the ACMD23, the upper 16 bit
> +  of the CMD23's argument is ignored. This will impact the reliable write operation
> +  and the RPMB block write operation, because these operations need to set the bit 31
> +  of the CMD23's argument. SDMA mode will default disable the ACMD23 mode. SD card do
> +  not has this limitation on these SoCs.

Use the compatible string or perhaps the version register like the 
sdhci-esdhc driver does.

Rob
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt b/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt
index d50144f5f1d2..a776f418a028 100644
--- a/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt
+++ b/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt
@@ -43,6 +43,14 @@  Optional properties:
   property allows user to change the delay target for the strobe input read clock.
   If not use this property, driver default set the delay target to value 7.
   Only eMMC HS400 mode need to take care of this property.
+- fsl,auto-cmd23-broken: disable the ACMD23 function of USDHC.
+  This is required for eMMC on imx6qpdl/imx6sx/imx7d when it use ADMA mode. Because
+  for these SoC, it do not support the ACMD23 completely, only take the 16 bit block
+  count from the 0x4 register (BLK_ATT) as argument for the ACMD23, the upper 16 bit
+  of the CMD23's argument is ignored. This will impact the reliable write operation
+  and the RPMB block write operation, because these operations need to set the bit 31
+  of the CMD23's argument. SDMA mode will default disable the ACMD23 mode. SD card do
+  not has this limitation on these SoCs.
 
 Examples: