Re: [PATCH V3] mmc: sdhci-msm: Update the software timeout value for sdhc

Adrian Hunter
2021-07-15T05:29:35Z

On 5/07/21 6:50 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@codeaurora.org>

A couple of minor nitpicks below. Fix those and you can add:

Acked-by: Adrian Hunter <adrian.hunter@intel.com>

> ---
>
> Changes since V2:
> - Updated 22 with 22LL to avoid compiler warning as suggested by
> Adrian Hunter.
> - Added a check to update software data timeout value if its value is
> less than the calculated hardware data timeout value as suggested
> by Veerabhadrarao Badiganti.
>
> Changes since V1:
> - Moved software data timeout update part to qcom specific file
> as suggested by Veerabhadrarao Badiganti.
> ---
> drivers/mmc/host/sdhci-msm.c | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index e44b7a6..64fb85e 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -2089,6 +2089,23 @@ static void sdhci_msm_cqe_disable(struct mmc_host *mmc, bool recovery)
> sdhci_cqe_disable(mmc, recovery);
> }
>
> +static void sdhci_msm_set_timeout(struct sdhci_host *host, struct mmc_command *cmd)
> +{
> +

Unnecessary blank line.

> + u32 count, start = 15;
> +
> + __sdhci_set_timeout(host, cmd);
> + count = sdhci_readb(host, SDHCI_TIMEOUT_CONTROL);
> + /*
> + * Update software timeout value if its value is less than hardware data
> + * timeout value. Qcom SoC hardware data timeout value was calculated
> + * using 4 * MCLK * 2^(count + 13). where MCLK = 1 / host->clock.
> + */
> + if (cmd && cmd->data && host->clock > 400000 && host->clock <= 50000000
> + && ((1 << (count + start)) > (10 * host->clock)))

'&&' is better at the end of the previous line

Also fewer parenthesis is more readable e.g.

if (cmd && cmd->data && host->clock > 400000 &&
host->clock <= 50000000 &&
(1 << (count + start)) > (10 * host->clock))

> + host->data_timeout = 22LL * NSEC_PER_SEC;
> +}
> +
> static const struct cqhci_host_ops sdhci_msm_cqhci_ops = {
> .enable = sdhci_msm_cqe_enable,
> .disable = sdhci_msm_cqe_disable,
> @@ -2438,6 +2455,7 @@ static const struct sdhci_ops sdhci_msm_ops = {
> .irq = sdhci_msm_cqe_irq,
> .dump_vendor_regs = sdhci_msm_dump_vendor_regs,
> .set_power = sdhci_set_power_noreg,
> + .set_timeout = sdhci_msm_set_timeout,
> };
>
> static const struct sdhci_pltfm_data sdhci_msm_pdata = {
>