On 3/12/22 12:58, gregkh@xxxxxxxxxxxxxxxxxxx wrote: > > The patch below does not apply to the 5.4-stable tree. > If someone wants it applied there, or to any other stable or longterm > tree, then please email the backport, including the original git commit > id to <stable@xxxxxxxxxxxxxxx>. > > Possible dependencies: > > c981cdfb9925 ("mmc: sdhci: Fix voltage switch delay") > fa0910107a9f ("mmc: sdhci: use FIELD_GET for preset value bit masks") Yes please cherry-pick fa0910107a9f then c981cdfb9925 Ditto for 4.19 and 4.14 too please. > > thanks, > > greg k-h > > ------------------ original commit in Linus's tree ------------------ > > From c981cdfb9925f64a364f13c2b4f98f877308a408 Mon Sep 17 00:00:00 2001 > From: Adrian Hunter <adrian.hunter@xxxxxxxxx> > Date: Mon, 28 Nov 2022 15:32:56 +0200 > Subject: [PATCH] mmc: sdhci: Fix voltage switch delay > > Commit 20b92a30b561 ("mmc: sdhci: update signal voltage switch code") > removed voltage switch delays from sdhci because mmc core had been > enhanced to support them. However that assumed that sdhci_set_ios() > did a single clock change, which it did not, and so the delays in mmc > core, which should have come after the first clock change, were not > effective. > > Fix by avoiding re-configuring UHS and preset settings when the clock > is turning on and the settings have not changed. That then also avoids > the associated clock changes, so that then sdhci_set_ios() does a single > clock change when voltage switching, and the mmc core delays become > effective. > > To do that has meant keeping track of driver strength (host->drv_type), > and cases of reinitialization (host->reinit_uhs). > > Note also, the 'turning_on_clk' restriction should not be necessary > but is done to minimize the impact of the change on stable kernels. > > Fixes: 20b92a30b561 ("mmc: sdhci: update signal voltage switch code") > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> > Link: https://lore.kernel.org/r/20221128133259.38305-2-adrian.hunter@xxxxxxxxx > Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > index fef03de85b99..c7ad32a75b57 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -373,6 +373,7 @@ static void sdhci_init(struct sdhci_host *host, int soft) > if (soft) { > /* force clock reconfiguration */ > host->clock = 0; > + host->reinit_uhs = true; > mmc->ops->set_ios(mmc, &mmc->ios); > } > } > @@ -2293,11 +2294,46 @@ void sdhci_set_uhs_signaling(struct sdhci_host *host, unsigned timing) > } > EXPORT_SYMBOL_GPL(sdhci_set_uhs_signaling); > > +static bool sdhci_timing_has_preset(unsigned char timing) > +{ > + switch (timing) { > + case MMC_TIMING_UHS_SDR12: > + case MMC_TIMING_UHS_SDR25: > + case MMC_TIMING_UHS_SDR50: > + case MMC_TIMING_UHS_SDR104: > + case MMC_TIMING_UHS_DDR50: > + case MMC_TIMING_MMC_DDR52: > + return true; > + }; > + return false; > +} > + > +static bool sdhci_preset_needed(struct sdhci_host *host, unsigned char timing) > +{ > + return !(host->quirks2 & SDHCI_QUIRK2_PRESET_VALUE_BROKEN) && > + sdhci_timing_has_preset(timing); > +} > + > +static bool sdhci_presetable_values_change(struct sdhci_host *host, struct mmc_ios *ios) > +{ > + /* > + * Preset Values are: Driver Strength, Clock Generator and SDCLK/RCLK > + * Frequency. Check if preset values need to be enabled, or the Driver > + * Strength needs updating. Note, clock changes are handled separately. > + */ > + return !host->preset_enabled && > + (sdhci_preset_needed(host, ios->timing) || host->drv_type != ios->drv_type); > +} > + > void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) > { > struct sdhci_host *host = mmc_priv(mmc); > + bool reinit_uhs = host->reinit_uhs; > + bool turning_on_clk = false; > u8 ctrl; > > + host->reinit_uhs = false; > + > if (ios->power_mode == MMC_POWER_UNDEFINED) > return; > > @@ -2323,6 +2359,8 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) > sdhci_enable_preset_value(host, false); > > if (!ios->clock || ios->clock != host->clock) { > + turning_on_clk = ios->clock && !host->clock; > + > host->ops->set_clock(host, ios->clock); > host->clock = ios->clock; > > @@ -2349,6 +2387,17 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) > > host->ops->set_bus_width(host, ios->bus_width); > > + /* > + * Special case to avoid multiple clock changes during voltage > + * switching. > + */ > + if (!reinit_uhs && > + turning_on_clk && > + host->timing == ios->timing && > + host->version >= SDHCI_SPEC_300 && > + !sdhci_presetable_values_change(host, ios)) > + return; > + > ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL); > > if (!(host->quirks & SDHCI_QUIRK_NO_HISPD_BIT)) { > @@ -2392,6 +2441,7 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) > } > > sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2); > + host->drv_type = ios->drv_type; > } else { > /* > * According to SDHC Spec v3.00, if the Preset Value > @@ -2419,19 +2469,14 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) > host->ops->set_uhs_signaling(host, ios->timing); > host->timing = ios->timing; > > - if (!(host->quirks2 & SDHCI_QUIRK2_PRESET_VALUE_BROKEN) && > - ((ios->timing == MMC_TIMING_UHS_SDR12) || > - (ios->timing == MMC_TIMING_UHS_SDR25) || > - (ios->timing == MMC_TIMING_UHS_SDR50) || > - (ios->timing == MMC_TIMING_UHS_SDR104) || > - (ios->timing == MMC_TIMING_UHS_DDR50) || > - (ios->timing == MMC_TIMING_MMC_DDR52))) { > + if (sdhci_preset_needed(host, ios->timing)) { > u16 preset; > > sdhci_enable_preset_value(host, true); > preset = sdhci_get_preset_value(host); > ios->drv_type = FIELD_GET(SDHCI_PRESET_DRV_MASK, > preset); > + host->drv_type = ios->drv_type; > } > > /* Re-enable SD Clock */ > @@ -3768,6 +3813,7 @@ int sdhci_resume_host(struct sdhci_host *host) > sdhci_init(host, 0); > host->pwr = 0; > host->clock = 0; > + host->reinit_uhs = true; > mmc->ops->set_ios(mmc, &mmc->ios); > } else { > sdhci_init(host, (mmc->pm_flags & MMC_PM_KEEP_POWER)); > @@ -3830,6 +3876,7 @@ int sdhci_runtime_resume_host(struct sdhci_host *host, int soft_reset) > /* Force clock and power re-program */ > host->pwr = 0; > host->clock = 0; > + host->reinit_uhs = true; > mmc->ops->start_signal_voltage_switch(mmc, &mmc->ios); > mmc->ops->set_ios(mmc, &mmc->ios); > > diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h > index d750c464bd1e..87a3aaa07438 100644 > --- a/drivers/mmc/host/sdhci.h > +++ b/drivers/mmc/host/sdhci.h > @@ -524,6 +524,8 @@ struct sdhci_host { > > unsigned int clock; /* Current clock (MHz) */ > u8 pwr; /* Current voltage */ > + u8 drv_type; /* Current UHS-I driver type */ > + bool reinit_uhs; /* Force UHS-related re-initialization */ > > bool runtime_suspended; /* Host is runtime suspended */ > bool bus_on; /* Bus power prevents runtime suspend */ >