| Message ID | b9cba2452c0166ef2fa69514d6ac8fbe7ee02883.1563259454.git.baolin.wang@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] mmc: host: sdhci-sprd: Fix the incorrect soft reset operation when runtime resuming | expand |
On 16/07/19 10:31 AM, Baolin Wang wrote: > In sdhci_runtime_resume_host() function, we will always do software reset > for all, which will cause Spreadtrum host controller work abnormally after > resuming. > > Thus for Spreadtrum platform that do not power down the SD/eMMC card during > runtime suspend, we should not do software reset for all. To fix this > issue, adding a specific reset operation that add one condition to validate > the MMC_CAP_AGGRESSIVE_PM to decide if we can do software reset for all or > just reset command and data lines. > > Signed-off-by: Baolin Wang <baolin.wang@linaro.org> > --- > Changes from v1: > - Add a specific reset operation instead of changing the core to avoid > affecting other hardware. > --- > drivers/mmc/host/sdhci-sprd.c | 38 +++++++++++++++++++++++++++++++++++++- > 1 file changed, 37 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/sdhci-sprd.c b/drivers/mmc/host/sdhci-sprd.c > index 603a5d9..174b566 100644 > --- a/drivers/mmc/host/sdhci-sprd.c > +++ b/drivers/mmc/host/sdhci-sprd.c > @@ -373,6 +373,42 @@ static unsigned int sdhci_sprd_get_max_timeout_count(struct sdhci_host *host) > return 1 << 31; > } > > +static void sdhci_sprd_reset(struct sdhci_host *host, u8 mask) > +{ > + struct mmc_host *mmc = host->mmc; > + ktime_t timeout; > + > + /* > + * When try to reset controller after runtime suspend, we should not > + * reset for all if the SD/eMMC card is not power down, just reset > + * command and data lines instead. Otherwise will meet some strange > + * behaviors for Spreadtrum host controller. > + */ > + if (host->runtime_suspended && (mask & SDHCI_RESET_ALL) && > + !(mmc->caps & MMC_CAP_AGGRESSIVE_PM)) > + mask = SDHCI_RESET_CMD | SDHCI_RESET_DATA; > + Here you could just call sdhci_reset(host, mask) instead of below. > + sdhci_writeb(host, mask, SDHCI_SOFTWARE_RESET); > + > + /* Wait max 100 ms */ > + timeout = ktime_add_ms(ktime_get(), 100); > + > + /* hw clears the bit when it's done */ > + while (1) { > + bool timedout = ktime_after(ktime_get(), timeout); > + > + if (!(sdhci_readb(host, SDHCI_SOFTWARE_RESET) & mask)) > + break; > + if (timedout) { > + pr_err("%s: Reset 0x%x never completed.\n", > + mmc_hostname(host->mmc), (int)mask); > + sdhci_dumpregs(host); > + return; > + } > + udelay(10); > + } > +} > + > static struct sdhci_ops sdhci_sprd_ops = { > .read_l = sdhci_sprd_readl, > .write_l = sdhci_sprd_writel, > @@ -381,7 +417,7 @@ static unsigned int sdhci_sprd_get_max_timeout_count(struct sdhci_host *host) > .get_max_clock = sdhci_sprd_get_max_clock, > .get_min_clock = sdhci_sprd_get_min_clock, > .set_bus_width = sdhci_set_bus_width, > - .reset = sdhci_reset, > + .reset = sdhci_sprd_reset, > .set_uhs_signaling = sdhci_sprd_set_uhs_signaling, > .hw_reset = sdhci_sprd_hw_reset, > .get_max_timeout_count = sdhci_sprd_get_max_timeout_count, >
diff --git a/drivers/mmc/host/sdhci-sprd.c b/drivers/mmc/host/sdhci-sprd.c index 603a5d9..174b566 100644 --- a/drivers/mmc/host/sdhci-sprd.c +++ b/drivers/mmc/host/sdhci-sprd.c @@ -373,6 +373,42 @@ static unsigned int sdhci_sprd_get_max_timeout_count(struct sdhci_host *host) return 1 << 31; } +static void sdhci_sprd_reset(struct sdhci_host *host, u8 mask) +{ + struct mmc_host *mmc = host->mmc; + ktime_t timeout; + + /* + * When try to reset controller after runtime suspend, we should not + * reset for all if the SD/eMMC card is not power down, just reset + * command and data lines instead. Otherwise will meet some strange + * behaviors for Spreadtrum host controller. + */ + if (host->runtime_suspended && (mask & SDHCI_RESET_ALL) && + !(mmc->caps & MMC_CAP_AGGRESSIVE_PM)) + mask = SDHCI_RESET_CMD | SDHCI_RESET_DATA; + + sdhci_writeb(host, mask, SDHCI_SOFTWARE_RESET); + + /* Wait max 100 ms */ + timeout = ktime_add_ms(ktime_get(), 100); + + /* hw clears the bit when it's done */ + while (1) { + bool timedout = ktime_after(ktime_get(), timeout); + + if (!(sdhci_readb(host, SDHCI_SOFTWARE_RESET) & mask)) + break; + if (timedout) { + pr_err("%s: Reset 0x%x never completed.\n", + mmc_hostname(host->mmc), (int)mask); + sdhci_dumpregs(host); + return; + } + udelay(10); + } +} + static struct sdhci_ops sdhci_sprd_ops = { .read_l = sdhci_sprd_readl, .write_l = sdhci_sprd_writel, @@ -381,7 +417,7 @@ static unsigned int sdhci_sprd_get_max_timeout_count(struct sdhci_host *host) .get_max_clock = sdhci_sprd_get_max_clock, .get_min_clock = sdhci_sprd_get_min_clock, .set_bus_width = sdhci_set_bus_width, - .reset = sdhci_reset, + .reset = sdhci_sprd_reset, .set_uhs_signaling = sdhci_sprd_set_uhs_signaling, .hw_reset = sdhci_sprd_hw_reset, .get_max_timeout_count = sdhci_sprd_get_max_timeout_count,
In sdhci_runtime_resume_host() function, we will always do software reset for all, which will cause Spreadtrum host controller work abnormally after resuming. Thus for Spreadtrum platform that do not power down the SD/eMMC card during runtime suspend, we should not do software reset for all. To fix this issue, adding a specific reset operation that add one condition to validate the MMC_CAP_AGGRESSIVE_PM to decide if we can do software reset for all or just reset command and data lines. Signed-off-by: Baolin Wang <baolin.wang@linaro.org> --- Changes from v1: - Add a specific reset operation instead of changing the core to avoid affecting other hardware. --- drivers/mmc/host/sdhci-sprd.c | 38 +++++++++++++++++++++++++++++++++++++- 1 file changed, 37 insertions(+), 1 deletion(-) -- 1.7.9.5