On 10 August 2018 at 12:11, Yinbo Zhu <yinbo.zhu@xxxxxxx> wrote:
> In tuning mode of operation, when TBCTL[TB_EN] is set, eSDHC may report
> one of the following errors :
> 1)Tuning error while running tuning operation where SYSCTL2[SAMPCLKSEL]
> will not get set even when SYSCTL2[EXTN] is reset. OR
> 2)Data transaction error (e.g. IRQSTAT[DCE], IRQSTAT[DEBE]) during data
> transaction errors.
> This issue occurs when the data window sampled within eSDHC is in full
> cycle. So, in that case, eSDHC is not able to find out the start and
> end points of the data window and sets the sampling pointer at default
> location (which is middle of the internal SD clock). If this sampling
> point coincides with the data eye boundary, then it can result in the
> above mentioned errors. Impact: Tuning mode of operation for SDR50,
> SDR104 or HS200 speed modes may not work properly
> Workaround: In case eSDHC reports tuning error or data errors in tuning
> mode of operation, by add the erratum A008171 support to fix the issue.
>
> Signed-off-by: Yinbo Zhu <yinbo.zhu@xxxxxxx>
> ---
> Change in v4:
> Use generic error code in tuning function.
>
> drivers/mmc/host/sdhci-esdhc.h | 1 +
> drivers/mmc/host/sdhci-of-esdhc.c | 44 ++++++++++++++++++++++++++++++++++++-
> drivers/mmc/host/sdhci.c | 9 ++++---
> drivers/mmc/host/sdhci.h | 1 +
> 4 files changed, 50 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-esdhc.h b/drivers/mmc/host/sdhci-esdhc.h
> index dfa58f8..3f16d9c 100644
> --- a/drivers/mmc/host/sdhci-esdhc.h
> +++ b/drivers/mmc/host/sdhci-esdhc.h
> @@ -60,6 +60,7 @@
> /* Tuning Block Control Register */
> #define ESDHC_TBCTL 0x120
> #define ESDHC_TB_EN 0x00000004
> +#define ESDHC_TBPTR 0x128
>
> /* Control Register for DMA transfer */
> #define ESDHC_DMA_SYSCTL 0x40c
> diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c
> index c9685c6..fcc29c3 100644
> --- a/drivers/mmc/host/sdhci-of-esdhc.c
> +++ b/drivers/mmc/host/sdhci-of-esdhc.c
> @@ -77,8 +77,10 @@ struct sdhci_esdhc {
> u8 vendor_ver;
> u8 spec_ver;
> bool quirk_incorrect_hostver;
> + bool quirk_fixup_tuning;
> unsigned int peripheral_clock;
> const struct esdhc_clk_fixup *clk_fixup;
> + u32 div_ratio;
> };
>
> /**
> @@ -574,6 +576,7 @@ static void esdhc_of_set_clock(struct sdhci_host *host, unsigned int clock)
> dev_dbg(mmc_dev(host->mmc), "desired SD clock: %d, actual: %d\n",
> clock, host->max_clk / pre_div / div);
> host->mmc->actual_clock = host->max_clk / pre_div / div;
> + esdhc->div_ratio = pre_div * div;
> pre_div >>= 1;
> div--;
>
> @@ -706,9 +709,24 @@ static int esdhc_signal_voltage_switch(struct mmc_host *mmc,
> }
> }
>
> +static struct soc_device_attribute soc_fixup_tuning[] = {
> + { .family = "QorIQ T1040", .revision = "1.0", },
> + { .family = "QorIQ T2080", .revision = "1.0", },
> + { .family = "QorIQ T1023", .revision = "1.0", },
> + { .family = "QorIQ LS1021A", .revision = "1.0", },
> + { .family = "QorIQ LS1080A", .revision = "1.0", },
> + { .family = "QorIQ LS2080A", .revision = "1.0", },
> + { .family = "QorIQ LS1012A", .revision = "1.0", },
> + { .family = "QorIQ LS1043A", .revision = "1.*", },
> + { .family = "QorIQ LS1046A", .revision = "1.0", },
> + { },
> +};
> +
> static int esdhc_execute_tuning(struct mmc_host *mmc, u32 opcode)
> {
> struct sdhci_host *host = mmc_priv(mmc);
> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> + struct sdhci_esdhc *esdhc = sdhci_pltfm_priv(pltfm_host);
> u32 val;
>
> /* Use tuning block for tuning procedure */
> @@ -722,7 +740,26 @@ static int esdhc_execute_tuning(struct mmc_host *mmc, u32 opcode)
> sdhci_writel(host, val, ESDHC_TBCTL);
> esdhc_clock_enable(host, true);
>
> - return sdhci_execute_tuning(mmc, opcode);
> + sdhci_execute_tuning(mmc, opcode);
> + if (-EAGAIN == host->tuning_err && esdhc->quirk_fixup_tuning) {
I would rather use this style:
if (host->tuning_err == -EAGAIN && esdhc->quirk_fixup_tuning) {
> +
> + /* program TBPTR[TB_WNDW_END_PTR] = 3*DIV_RATIO and
> + * program TBPTR[TB_WNDW_START_PTR] = 5*DIV_RATIO
> + */
> + val = sdhci_readl(host, ESDHC_TBPTR);
> + val = (val & ~((0x7f << 8) | 0x7f)) |
> + (3 * esdhc->div_ratio) | ((5 * esdhc->div_ratio) << 8);
> + sdhci_writel(host, val, ESDHC_TBPTR);
> +
> + /* program the software tuning mode by setting
> + * TBCTL[TB_MODE]=2'h3
> + */
> + val = sdhci_readl(host, ESDHC_TBCTL);
> + val |= 0x3;
> + sdhci_writel(host, val, ESDHC_TBCTL);
> + sdhci_execute_tuning(mmc, opcode);
> + }
> + return 0;
> }
>
> #ifdef CONFIG_PM_SLEEP
> @@ -897,6 +934,11 @@ static int sdhci_esdhc_probe(struct platform_device *pdev)
>
> pltfm_host = sdhci_priv(host);
> esdhc = sdhci_pltfm_priv(pltfm_host);
> + if (soc_device_match(soc_fixup_tuning))
> + esdhc->quirk_fixup_tuning = true;
> + else
> + esdhc->quirk_fixup_tuning = false;
> +
> if (esdhc->vendor_ver == VENDOR_V_22)
> host->quirks2 |= SDHCI_QUIRK2_HOST_NO_CMD23;
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 1c828e0..caf1839 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -2213,7 +2213,7 @@ static void sdhci_send_tuning(struct sdhci_host *host, u32 opcode)
>
> }
>
> -static void __sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
> +static int __sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
> {
> int i;
>
> @@ -2230,13 +2230,13 @@ static void __sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
> pr_info("%s: Tuning timeout, falling back to fixed sampling clock\n",
> mmc_hostname(host->mmc));
> sdhci_abort_tuning(host, opcode);
> - return;
> + return -ETIMEDOUT;
> }
>
> ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> if (!(ctrl & SDHCI_CTRL_EXEC_TUNING)) {
> if (ctrl & SDHCI_CTRL_TUNED_CLK)
> - return; /* Success! */
> + return -ETIMEDOUT; /* Success! */
This should be: return 0;
I realize that in practice it doesn't matter for you, as you only look
at -EAGAIN.
> break;
> }
>
> @@ -2248,6 +2248,7 @@ static void __sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
> pr_info("%s: Tuning failed, falling back to fixed sampling clock\n",
> mmc_hostname(host->mmc));
> sdhci_reset_tuning(host);
> + return -EAGAIN;
> }
>
> int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)
> @@ -2309,7 +2310,7 @@ int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)
>
> sdhci_start_tuning(host);
>
> - __sdhci_execute_tuning(host, opcode);
> + host->tuning_err = __sdhci_execute_tuning(host, opcode);
>
> sdhci_end_tuning(host);
> out:
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index 23966f8..6c4ed6d 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -554,6 +554,7 @@ struct sdhci_host {
>
> unsigned int tuning_count; /* Timer count for re-tuning */
> unsigned int tuning_mode; /* Re-tuning mode supported by host */
> + unsigned int tuning_err; /* Error code for re-tuning */
> #define SDHCI_TUNING_MODE_1 0
> #define SDHCI_TUNING_MODE_2 1
> #define SDHCI_TUNING_MODE_3 2
> --
> 1.7.1
>
I did the trivial changes, resolved a conflict and queued this up for
v4.20, thanks!
Kind regards
Uffe
