[U-Boot] [PATCH] mmc: sdhci: revert "mmc: sdhci: Claer high speed if not supported"

Jaehoon Chung jh80.chung at samsung.com
Thu Jul 28 08:34:15 CEST 2016


Hi All,

On 07/26/2016 07:03 PM, Jaehoon Chung wrote:
> This "commit 429790026021d522d51617217d4b86218cca5750" is wrong.
> SDHCI_QUIRK_NO_HISPD_BIT is for skipping to set CTRL_HISPD bit.
> 
> For example, Exynos didn't have CTRL_HISPD. But Highspeed mode
> is supported.
> (This quirks doesn't mean  that driver didn't support the Highseepd mode.)
> 
> Note: If driver didn't support the Highspeed Mode, use or add the other
> quirks.
> 
> After applied this patch, all Exynos SoCs are just running with 25MHz.

SDHCI_QUIRK_NO_HISPD had added from me.
At that time, it meant the Controller doesn't have the SDHCI_CTRL_HISPD bit[2].
In exynos, this bit is using as OUTEDGINV (Output Egde Inversion).
I added SDHCI_QUIRK_NO_HISPD to prevent wrong bit operation likes this.

And in drivers/mmc/mmc.c 1328 line, 

mmc->card_caps &= mmc->cfg->host_caps;

After reading card's capabilities, if card didn't support those, then it's cleared.
I don't know why cleared these capabilities before checking the card's capabilities.

After applied commit "42979002602"

Device: SAMSUNG SDHCI
Manufacturer ID: 3
OEM: 5344
Name: SU16G
Tran Speed: 25000000
Rd Block Len: 512
SD version 3.0
High Capacity: Yes
Capacity: 14.8 GiB
Bus Width: 4-bit
Erase Group Size: 512 Bytes

After reverted commit "42979002602"

Device: SAMSUNG SDHCI
Manufacturer ID: 3
OEM: 5344
Name: SU16G
Tran Speed: 50000000
Rd Block Len: 512
SD version 3.0
High Capacity: Yes
Capacity: 14.8 GiB
Bus Width: 4-bit
Erase Group Size: 512 Bytes

There is no purpose, it needs to revert for Other SoCs.

Best Regards,
Jaehoon Chung

> 
> Signed-off-by: Jaehoon Chung <jh80.chung at samsung.com>
> ---
>  drivers/mmc/sdhci.c | 3 ---
>  1 file changed, 3 deletions(-)
> 
> diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
> index 9fdbed8..1fa4038 100644
> --- a/drivers/mmc/sdhci.c
> +++ b/drivers/mmc/sdhci.c
> @@ -553,9 +553,6 @@ int sdhci_setup_cfg(struct mmc_config *cfg, const char *name, int buswidth,
>  			cfg->host_caps |= MMC_MODE_8BIT;
>  	}
>  
> -	if (quirks & SDHCI_QUIRK_NO_HISPD_BIT)
> -		cfg->host_caps &= ~(MMC_MODE_HS | MMC_MODE_HS_52MHz);
> -
>  	if (host_caps)
>  		cfg->host_caps |= host_caps;
>  
> 



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