2024-04-02 09:40:46

by Maksim Kiselev

Subject: [PATCH v1] mmc: sdhci-of-dwcmshc: th1520: Increase tuning loop count to 128

Fix SD card tuning error by increasing tuning loop count
from 40(MAX_TUNING_LOOP) to 128.

For some reason the tuning algorithm requires to move through all the taps
of delay line even if the THRESHOLD_MODE (bit 2 in AT_CTRL_R) is used
instead of the LARGEST_WIN_MODE.

Tested-by: Drew Fustini <[email protected]>
Tested-by: Xi Ruoyao <[email protected]>
Signed-off-by: Maksim Kiselev <[email protected]>
---
Previous discussion was here:
https://lore.kernel.org/lkml/CALHCpMhc1F5Ue7U_gsDXREHUZRVQJNYRCJxYxoNqbN=-39jf7A@mail.gmail.com/

drivers/mmc/host/sdhci-of-dwcmshc.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
index 8d6cfb648096..1001b6ea1a89 100644
--- a/drivers/mmc/host/sdhci-of-dwcmshc.c
+++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
@@ -706,6 +706,7 @@ static int th1520_execute_tuning(struct sdhci_host *host, u32 opcode)

/* perform tuning */
sdhci_start_tuning(host);
+ host->tuning_loop_count = 128;
host->tuning_err = __sdhci_execute_tuning(host, opcode);
if (host->tuning_err) {
/* disable auto-tuning upon tuning error */
--
2.40.1

2024-04-04 08:42:29

by Adrian Hunter

Subject: Re: [PATCH v1] mmc: sdhci-of-dwcmshc: th1520: Increase tuning loop count to 128

On 2/04/24 12:35, Maksim Kiselev wrote:
> Fix SD card tuning error by increasing tuning loop count
> from 40(MAX_TUNING_LOOP) to 128.
>
> For some reason the tuning algorithm requires to move through all the taps
> of delay line even if the THRESHOLD_MODE (bit 2 in AT_CTRL_R) is used
> instead of the LARGEST_WIN_MODE.
>
> Tested-by: Drew Fustini <[email protected]>
> Tested-by: Xi Ruoyao <[email protected]>
> Signed-off-by: Maksim Kiselev <[email protected]>

Acked-by: Adrian Hunter <[email protected]>

> ---
> Previous discussion was here:
> https://lore.kernel.org/lkml/CALHCpMhc1F5Ue7U_gsDXREHUZRVQJNYRCJxYxoNqbN=-39jf7A@mail.gmail.com/
>
> drivers/mmc/host/sdhci-of-dwcmshc.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
> index 8d6cfb648096..1001b6ea1a89 100644
> --- a/drivers/mmc/host/sdhci-of-dwcmshc.c
> +++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
> @@ -706,6 +706,7 @@ static int th1520_execute_tuning(struct sdhci_host *host, u32 opcode)
>
> /* perform tuning */
> sdhci_start_tuning(host);
> + host->tuning_loop_count = 128;
> host->tuning_err = __sdhci_execute_tuning(host, opcode);
> if (host->tuning_err) {
> /* disable auto-tuning upon tuning error */

2024-04-04 09:41:26

by Ulf Hansson

Subject: Re: [PATCH v1] mmc: sdhci-of-dwcmshc: th1520: Increase tuning loop count to 128

On Tue, 2 Apr 2024 at 11:36, Maksim Kiselev <[email protected]> wrote:
>
> Fix SD card tuning error by increasing tuning loop count
> from 40(MAX_TUNING_LOOP) to 128.
>
> For some reason the tuning algorithm requires to move through all the taps
> of delay line even if the THRESHOLD_MODE (bit 2 in AT_CTRL_R) is used
> instead of the LARGEST_WIN_MODE.
>
> Tested-by: Drew Fustini <[email protected]>
> Tested-by: Xi Ruoyao <[email protected]>
> Signed-off-by: Maksim Kiselev <[email protected]>

Applied for fixes and by adding a fixes+stable tag, thanks!

Kind regards
Uffe



> ---
> Previous discussion was here:
> https://lore.kernel.org/lkml/CALHCpMhc1F5Ue7U_gsDXREHUZRVQJNYRCJxYxoNqbN=-39jf7A@mail.gmail.com/
>
> drivers/mmc/host/sdhci-of-dwcmshc.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
> index 8d6cfb648096..1001b6ea1a89 100644
> --- a/drivers/mmc/host/sdhci-of-dwcmshc.c
> +++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
> @@ -706,6 +706,7 @@ static int th1520_execute_tuning(struct sdhci_host *host, u32 opcode)
>
> /* perform tuning */
> sdhci_start_tuning(host);
> + host->tuning_loop_count = 128;
> host->tuning_err = __sdhci_execute_tuning(host, opcode);
> if (host->tuning_err) {
> /* disable auto-tuning upon tuning error */
> --
> 2.40.1
>