diff mbox series

[RESEND] Revert "clk: rockchip: fix wrong mmc sample phase shift for rk3328"

Message ID c80eb52e34c03f817586b6b7912fbd4e31be9079.1589475794.git.robin.murphy@arm.com (mailing list archive)
State Mainlined
Commit 465931e70881476a210d44705102ef8b6ee6cdb0
Headers show
Series [RESEND] Revert "clk: rockchip: fix wrong mmc sample phase shift for rk3328" | expand

Commit Message

Robin Murphy June 18, 2020, 5:56 p.m. UTC
This reverts commit 82f4b67f018c88a7cc9337f0067ed3d6ec352648.

According to a subsequent revert in the vendor kernel, the original
change was based on unclear documentation and was in fact incorrect.

Emprically, my board's HS200 eMMC at 200MHZ apparently gets lucky with a
phase where this had no impact, but limiting max-frequency to 150MHz to
match the nominal capability of the I/O pins made it virtually unusable,
constantly throwing errors and retuning. With this revert, it starts
behaving perfectly at 150MHz too.

Fixes: 82f4b67f018c ("clk: rockchip: fix wrong mmc sample phase shift for rk3328")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---

Resending with the edited commit log I actually meant, rather than the
earlier draft I managed to generate the previuous patch from, since that
one seems to have slipped through the cracks anyway.

ybetter commit message
 drivers/clk/rockchip/clk-rk3328.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

Comments

Shawn Lin June 19, 2020, 9:30 a.m. UTC | #1
On 2020/6/19 1:56, Robin Murphy wrote:
> This reverts commit 82f4b67f018c88a7cc9337f0067ed3d6ec352648.
> 
> According to a subsequent revert in the vendor kernel, the original
> change was based on unclear documentation and was in fact incorrect.
> 

Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>

> Emprically, my board's HS200 eMMC at 200MHZ apparently gets lucky with a
> phase where this had no impact, but limiting max-frequency to 150MHz to
> match the nominal capability of the I/O pins made it virtually unusable,
> constantly throwing errors and retuning. With this revert, it starts
> behaving perfectly at 150MHz too.
> 
> Fixes: 82f4b67f018c ("clk: rockchip: fix wrong mmc sample phase shift for rk3328")
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
> 
> Resending with the edited commit log I actually meant, rather than the
> earlier draft I managed to generate the previuous patch from, since that
> one seems to have slipped through the cracks anyway.
> 
> ybetter commit message
>   drivers/clk/rockchip/clk-rk3328.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/clk/rockchip/clk-rk3328.c b/drivers/clk/rockchip/clk-rk3328.c
> index c186a1985bf4..2429b7c2a8b3 100644
> --- a/drivers/clk/rockchip/clk-rk3328.c
> +++ b/drivers/clk/rockchip/clk-rk3328.c
> @@ -808,22 +808,22 @@ static struct rockchip_clk_branch rk3328_clk_branches[] __initdata = {
>   	MMC(SCLK_SDMMC_DRV, "sdmmc_drv", "clk_sdmmc",
>   	    RK3328_SDMMC_CON0, 1),
>   	MMC(SCLK_SDMMC_SAMPLE, "sdmmc_sample", "clk_sdmmc",
> -	    RK3328_SDMMC_CON1, 0),
> +	    RK3328_SDMMC_CON1, 1),
>   
>   	MMC(SCLK_SDIO_DRV, "sdio_drv", "clk_sdio",
>   	    RK3328_SDIO_CON0, 1),
>   	MMC(SCLK_SDIO_SAMPLE, "sdio_sample", "clk_sdio",
> -	    RK3328_SDIO_CON1, 0),
> +	    RK3328_SDIO_CON1, 1),
>   
>   	MMC(SCLK_EMMC_DRV, "emmc_drv", "clk_emmc",
>   	    RK3328_EMMC_CON0, 1),
>   	MMC(SCLK_EMMC_SAMPLE, "emmc_sample", "clk_emmc",
> -	    RK3328_EMMC_CON1, 0),
> +	    RK3328_EMMC_CON1, 1),
>   
>   	MMC(SCLK_SDMMC_EXT_DRV, "sdmmc_ext_drv", "clk_sdmmc_ext",
>   	    RK3328_SDMMC_EXT_CON0, 1),
>   	MMC(SCLK_SDMMC_EXT_SAMPLE, "sdmmc_ext_sample", "clk_sdmmc_ext",
> -	    RK3328_SDMMC_EXT_CON1, 0),
> +	    RK3328_SDMMC_EXT_CON1, 1),
>   };
>   
>   static const char *const rk3328_critical_clocks[] __initconst = {
>
Heiko Stuebner July 8, 2020, 2:23 p.m. UTC | #2
On Thu, 18 Jun 2020 18:56:29 +0100, Robin Murphy wrote:
> This reverts commit 82f4b67f018c88a7cc9337f0067ed3d6ec352648.
> 
> According to a subsequent revert in the vendor kernel, the original
> change was based on unclear documentation and was in fact incorrect.
> 
> Emprically, my board's HS200 eMMC at 200MHZ apparently gets lucky with a
> phase where this had no impact, but limiting max-frequency to 150MHz to
> match the nominal capability of the I/O pins made it virtually unusable,
> constantly throwing errors and retuning. With this revert, it starts
> behaving perfectly at 150MHz too.

Applied, thanks!

[1/1] clk: rockchip: Revert "fix wrong mmc sample phase shift for rk3328"
      commit: 465931e70881476a210d44705102ef8b6ee6cdb0

Best regards,
diff mbox series

Patch

diff --git a/drivers/clk/rockchip/clk-rk3328.c b/drivers/clk/rockchip/clk-rk3328.c
index c186a1985bf4..2429b7c2a8b3 100644
--- a/drivers/clk/rockchip/clk-rk3328.c
+++ b/drivers/clk/rockchip/clk-rk3328.c
@@ -808,22 +808,22 @@  static struct rockchip_clk_branch rk3328_clk_branches[] __initdata = {
 	MMC(SCLK_SDMMC_DRV, "sdmmc_drv", "clk_sdmmc",
 	    RK3328_SDMMC_CON0, 1),
 	MMC(SCLK_SDMMC_SAMPLE, "sdmmc_sample", "clk_sdmmc",
-	    RK3328_SDMMC_CON1, 0),
+	    RK3328_SDMMC_CON1, 1),
 
 	MMC(SCLK_SDIO_DRV, "sdio_drv", "clk_sdio",
 	    RK3328_SDIO_CON0, 1),
 	MMC(SCLK_SDIO_SAMPLE, "sdio_sample", "clk_sdio",
-	    RK3328_SDIO_CON1, 0),
+	    RK3328_SDIO_CON1, 1),
 
 	MMC(SCLK_EMMC_DRV, "emmc_drv", "clk_emmc",
 	    RK3328_EMMC_CON0, 1),
 	MMC(SCLK_EMMC_SAMPLE, "emmc_sample", "clk_emmc",
-	    RK3328_EMMC_CON1, 0),
+	    RK3328_EMMC_CON1, 1),
 
 	MMC(SCLK_SDMMC_EXT_DRV, "sdmmc_ext_drv", "clk_sdmmc_ext",
 	    RK3328_SDMMC_EXT_CON0, 1),
 	MMC(SCLK_SDMMC_EXT_SAMPLE, "sdmmc_ext_sample", "clk_sdmmc_ext",
-	    RK3328_SDMMC_EXT_CON1, 0),
+	    RK3328_SDMMC_EXT_CON1, 1),
 };
 
 static const char *const rk3328_critical_clocks[] __initconst = {