2018-06-29 15:31:59

by hieagle

Subject: [PATCH] mmc: dw_mmc: fix errors to use card read/write threshold for HS400 mode

The card write threshold is applicable for HS400 mode only, so it should
return back except HS400 timing mode.

The card read threshold is also required for HS400 mode as the host
controller incorrectly samples the data if the card clock stops within
a block transfer.

Signed-off-by: Huanlin.Ke <[email protected]>
Signed-off-by: zhangbo_a <[email protected]>
---
drivers/mmc/host/dw_mmc.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 623f4d2..d4e6983 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -1065,7 +1065,7 @@ static void dw_mci_ctrl_thld(struct dw_mci *host, struct mmc_data *data)
* It's used when HS400 mode is enabled.
*/
if (data->flags & MMC_DATA_WRITE &&
- !(host->timing != MMC_TIMING_MMC_HS400))
+ (host->timing != MMC_TIMING_MMC_HS400))
return;

if (data->flags & MMC_DATA_WRITE)
@@ -1074,6 +1074,7 @@ static void dw_mci_ctrl_thld(struct dw_mci *host, struct mmc_data *data)
enable = SDMMC_CARD_RD_THR_EN;

if (host->timing != MMC_TIMING_MMC_HS200 &&
+ host->timing != MMC_TIMING_MMC_HS400 &&
host->timing != MMC_TIMING_UHS_SDR104)
goto disable;

--
2.7.4

2018-07-02 14:39:08

by Ulf Hansson

Subject: Re: [PATCH] mmc: dw_mmc: fix errors to use card read/write threshold for HS400 mode

On 29 June 2018 at 15:59, Huanlin.Ke <[email protected]> wrote:
> The card write threshold is applicable for HS400 mode only, so it should
> return back except HS400 timing mode.
>
> The card read threshold is also required for HS400 mode as the host
> controller incorrectly samples the data if the card clock stops within
> a block transfer.
>
> Signed-off-by: Huanlin.Ke <[email protected]>
> Signed-off-by: zhangbo_a <[email protected]>

Thanks for your patch!

I have just applied an earlier version of the patch, posted by Qing
Xia from Hisilicon.
https://patchwork.kernel.org/patch/10434913/

If it works for you as well, I can add your tested by tags for it.

Also, can you perhaps point me to a commit which introduced the problem?

Kind regards
Uffe

> ---
> drivers/mmc/host/dw_mmc.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> index 623f4d2..d4e6983 100644
> --- a/drivers/mmc/host/dw_mmc.c
> +++ b/drivers/mmc/host/dw_mmc.c
> @@ -1065,7 +1065,7 @@ static void dw_mci_ctrl_thld(struct dw_mci *host, struct mmc_data *data)
> * It's used when HS400 mode is enabled.
> */
> if (data->flags & MMC_DATA_WRITE &&
> - !(host->timing != MMC_TIMING_MMC_HS400))
> + (host->timing != MMC_TIMING_MMC_HS400))
> return;
>
> if (data->flags & MMC_DATA_WRITE)
> @@ -1074,6 +1074,7 @@ static void dw_mci_ctrl_thld(struct dw_mci *host, struct mmc_data *data)
> enable = SDMMC_CARD_RD_THR_EN;
>
> if (host->timing != MMC_TIMING_MMC_HS200 &&
> + host->timing != MMC_TIMING_MMC_HS400 &&
> host->timing != MMC_TIMING_UHS_SDR104)
> goto disable;
>
> --
> 2.7.4
>