Re: [PATCH V1] mmc: sdhci: Update the software timeout value for sdhc

[Veerabhadrarao Badiganti]

On 6/16/2021 2:55 PM, Shaik Sajida Bhanu wrote:
> Whenever SDHC run at clock rate 50MHZ or below, the hardware data
> timeout value will be 21.47secs, which is approx. 22secs and we have
> a current software timeout value as 10secs. We have to set software
> timeout value more than the hardware data timeout value to avioid seeing
> the below register dumps.
>
> [  332.953670] mmc2: Timeout waiting for hardware interrupt.
> [  332.959608] mmc2: sdhci: ============ SDHCI REGISTER DUMP ===========
> [  332.966450] mmc2: sdhci: Sys addr:  0x00000000 | Version:  0x00007202
> [  332.973256] mmc2: sdhci: Blk size:  0x00000200 | Blk cnt:  0x00000001
> [  332.980054] mmc2: sdhci: Argument:  0x00000000 | Trn mode: 0x00000027
> [  332.986864] mmc2: sdhci: Present:   0x01f801f6 | Host ctl: 0x0000001f
> [  332.993671] mmc2: sdhci: Power:     0x00000001 | Blk gap:  0x00000000
> [  333.000583] mmc2: sdhci: Wake-up:   0x00000000 | Clock:    0x00000007
> [  333.007386] mmc2: sdhci: Timeout:   0x0000000e | Int stat: 0x00000000
> [  333.014182] mmc2: sdhci: Int enab:  0x03ff100b | Sig enab: 0x03ff100b
> [  333.020976] mmc2: sdhci: ACmd stat: 0x00000000 | Slot int: 0x00000000
> [  333.027771] mmc2: sdhci: Caps:      0x322dc8b2 | Caps_1:   0x0000808f
> [  333.034561] mmc2: sdhci: Cmd:       0x0000183a | Max curr: 0x00000000
> [  333.041359] mmc2: sdhci: Resp[0]:   0x00000900 | Resp[1]:  0x00000000
> [  333.048157] mmc2: sdhci: Resp[2]:   0x00000000 | Resp[3]:  0x00000000
> [  333.054945] mmc2: sdhci: Host ctl2: 0x00000000
> [  333.059657] mmc2: sdhci: ADMA Err:  0x00000000 | ADMA Ptr:
> 0x0000000ffffff218
> [  333.067178] mmc2: sdhci_msm: ----------- VENDOR REGISTER DUMP
> -----------
> [  333.074343] mmc2: sdhci_msm: DLL sts: 0x00000000 | DLL cfg:
> 0x6000642c | DLL cfg2: 0x0020a000
> [  333.083417] mmc2: sdhci_msm: DLL cfg3: 0x00000000 | DLL usr ctl:
> 0x00000000 | DDR cfg: 0x80040873
> [  333.092850] mmc2: sdhci_msm: Vndr func: 0x00008a9c | Vndr func2 :
> 0xf88218a8 Vndr func3: 0x02626040
> [  333.102371] mmc2: sdhci: ============================================
>
> So, set software timeout value more than hardware timeout value.
>
> Signed-off-by: Shaik Sajida Bhanu <sbhanu@xxxxxxxxxxxxxx>
> ---
>   drivers/mmc/host/sdhci.c | 9 ++++++++-
>   1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index bf238ad..1386f7d 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -1670,7 +1670,14 @@ static bool sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd)
>   	else if (!cmd->data && cmd->busy_timeout > 9000)
>   		timeout += DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ;
>   	else
> -		timeout += 10 * HZ;
> +	       /*
> +		* In some of the conditions hardware data timeout value could be
> +		* approx 21.5 seconds and driver is setting software data timeout
> +		* value less than the hardware data timeout value and software data
> +		* timeout value should be more than the hardware data timeout value.
> +		* So, set software data timeout value more than 21.5 sec i.e. 22sec.
> +		*/
> +		timeout += 22 * HZ;

This timeout is qcom SDHC specific.
I think right way is to, define your own set_timeout op and update 
host->data_timeout
in that as per qcom SDHC requirements.

>   	sdhci_mod_timer(host, cmd->mrq, timeout);
>   
>   	if (host->use_external_dma)