Re: [PATCH V5 11/26] mmc: sdhci-uhs2: add reset function and uhs2_mode function
From: Victor Shih
Date: Tue Dec 13 2022 - 03:46:29 EST
Hi, Adrian
On Wed, Nov 2, 2022 at 1:13 AM Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
>
> On 19/10/22 14:06, Victor Shih wrote:
> > Sdhci_uhs2_reset() does a UHS-II specific reset operation.
> >
> > Signed-off-by: Ben Chuang <ben.chuang@xxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx>
> > Signed-off-by: Victor Shih <victor.shih@xxxxxxxxxxxxxxxxxxx>
> > ---
> > drivers/mmc/host/sdhci-pci-core.c | 1 +
> > drivers/mmc/host/sdhci-pci-gli.c | 1 +
> > drivers/mmc/host/sdhci-uhs2.c | 68 +++++++++++++++++++++++++++++++
> > drivers/mmc/host/sdhci-uhs2.h | 3 ++
> > drivers/mmc/host/sdhci.c | 3 +-
> > drivers/mmc/host/sdhci.h | 14 +++++++
> > 6 files changed, 89 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
> > index 34ea1acbb3cc..cba5bba994b8 100644
> > --- a/drivers/mmc/host/sdhci-pci-core.c
> > +++ b/drivers/mmc/host/sdhci-pci-core.c
> > @@ -1955,6 +1955,7 @@ static const struct sdhci_ops sdhci_pci_ops = {
> > .reset = sdhci_reset,
> > .set_uhs_signaling = sdhci_set_uhs_signaling,
> > .hw_reset = sdhci_pci_hw_reset,
> > + .uhs2_reset = sdhci_uhs2_reset,
>
> AFAICT this isn't needed
>
I will update it in the patch#10 of the new [PATCH V6].
> > };
> >
> > /*****************************************************************************\
> > diff --git a/drivers/mmc/host/sdhci-pci-gli.c b/drivers/mmc/host/sdhci-pci-gli.c
> > index 4d509f656188..607cf69f45d0 100644
> > --- a/drivers/mmc/host/sdhci-pci-gli.c
> > +++ b/drivers/mmc/host/sdhci-pci-gli.c
> > @@ -1097,6 +1097,7 @@ static const struct sdhci_ops sdhci_gl9755_ops = {
> > .reset = sdhci_reset,
> > .set_uhs_signaling = sdhci_set_uhs_signaling,
> > .voltage_switch = sdhci_gli_voltage_switch,
> > + .uhs2_reset = sdhci_uhs2_reset,
> > };
> >
> > const struct sdhci_pci_fixes sdhci_gl9755 = {
> > diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> > index 08905ed081fb..0e82f98d1967 100644
> > --- a/drivers/mmc/host/sdhci-uhs2.c
> > +++ b/drivers/mmc/host/sdhci-uhs2.c
> > @@ -10,6 +10,7 @@
> > * Author: AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx>
> > */
> >
> > +#include <linux/delay.h>
> > #include <linux/module.h>
> >
> > #include "sdhci.h"
> > @@ -49,6 +50,73 @@ void sdhci_uhs2_dump_regs(struct sdhci_host *host)
> > }
> > EXPORT_SYMBOL_GPL(sdhci_uhs2_dump_regs);
> >
> > +/*****************************************************************************\
> > + * *
> > + * Low level functions *
> > + * *
> > +\*****************************************************************************/
> > +
> > +bool sdhci_uhs2_mode(struct sdhci_host *host)
> > +{
> > + if ((host->mmc->caps2 & MMC_CAP2_SD_UHS2) &&
> > + (IS_ENABLED(CONFIG_MMC_SDHCI_UHS2) &&
> > + (host->version >= SDHCI_SPEC_400) &&
> > + (host->mmc->flags & MMC_UHS2_SUPPORT)))
> > + return true;
> > + else
> > + return false;
>
> For now, let's just make this:
>
> return host->mmc->flags & MMC_UHS2_SUPPORT;
>
I will update it in the patch#10 of the new [PATCH V6].
> > +}
> > +
> > +/**
> > + * sdhci_uhs2_reset - invoke SW reset
> > + * @host: SDHCI host
> > + * @mask: Control mask
> > + *
> > + * Invoke SW reset, depending on a bit in @mask and wait for completion.
> > + */
> > +void sdhci_uhs2_reset(struct sdhci_host *host, u16 mask)
> > +{
> > + unsigned long timeout;
> > + u32 val;
> > +
> > + if (!(sdhci_uhs2_mode(host))) {
>
> That isn't possible.
>
I will update it in the patch#10 of the new [PATCH V6].
> > + /**
> > + * u8 mask for legacy.
> > + * u16 mask for uhs-2.
> > + */
> > + u8 u8_mask;
> > +
> > + u8_mask = (mask & 0xFF);
> > + sdhci_reset(host, u8_mask);
>
> Probably should call host->ops->reset() but !sdhci_uhs2_mode(host)
> isn't possible
>
I will update it in the patch#10 of the new [PATCH V6].
> > +
> > + return;
> > + }
> > +
> > + sdhci_writew(host, mask, SDHCI_UHS2_SW_RESET);
> > +
> > + if (mask & SDHCI_UHS2_SW_RESET_FULL) {
> > + host->clock = 0;
> > + /* Reset-all turns off SD Bus Power */
> > + if (host->quirks2 & SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON)
> > + sdhci_runtime_pm_bus_off(host);
>
> We don't know what other drivers will opt for UHS-II
> support, but I doubt this quirk will be used, so let's
> not support SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON for UHS-II
>
I will update it in the patch#10 of the new [PATCH V6].
> > + }
> > +
> > + /* Wait max 100 ms */
> > + timeout = 10000;
>
> Isn't that 10ms
>
I will update it in the patch#10 of the new [PATCH V6].
> > +
> > + /* hw clears the bit when it's done */
> > + if (read_poll_timeout_atomic(sdhci_readw, val, !(val & mask), 10,
> > + timeout, true, host, SDHCI_UHS2_SW_RESET)) {
> > + pr_err("%s: %s: Reset 0x%x never completed.\n",
> > + __func__, mmc_hostname(host->mmc), (int)mask);
> > + pr_err("%s: clean reset bit\n",
> > + mmc_hostname(host->mmc));
> > + sdhci_writeb(host, 0, SDHCI_UHS2_SW_RESET);
> > + return;
> > + }
> > +}
> > +EXPORT_SYMBOL_GPL(sdhci_uhs2_reset);
> > +
> > /*****************************************************************************\
> > * *
> > * Driver init/exit *
> > diff --git a/drivers/mmc/host/sdhci-uhs2.h b/drivers/mmc/host/sdhci-uhs2.h
> > index afdb05d6056b..31776dcca5cf 100644
> > --- a/drivers/mmc/host/sdhci-uhs2.h
> > +++ b/drivers/mmc/host/sdhci-uhs2.h
> > @@ -11,6 +11,7 @@
> > #define __SDHCI_UHS2_H
> >
> > #include <linux/bits.h>
> > +#include <linux/iopoll.h>
>
> Not needed in header. Can just be in .c
>
I will update it in the patch#10 of the new [PATCH V6].
> >
> > /*
> > * UHS-II Controller registers
> > @@ -210,5 +211,7 @@
> > struct sdhci_host;
> >
> > void sdhci_uhs2_dump_regs(struct sdhci_host *host);
> > +bool sdhci_uhs2_mode(struct sdhci_host *host);
> > +void sdhci_uhs2_reset(struct sdhci_host *host, u16 mask);
> >
> > #endif /* __SDHCI_UHS2_H */
> > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> > index 2cdd183c8ada..bd017c59a020 100644
> > --- a/drivers/mmc/host/sdhci.c
> > +++ b/drivers/mmc/host/sdhci.c
> > @@ -194,13 +194,14 @@ static void sdhci_runtime_pm_bus_on(struct sdhci_host *host)
> > pm_runtime_get_noresume(mmc_dev(host->mmc));
> > }
> >
> > -static void sdhci_runtime_pm_bus_off(struct sdhci_host *host)
> > +void sdhci_runtime_pm_bus_off(struct sdhci_host *host)
> > {
> > if (!host->bus_on)
> > return;
> > host->bus_on = false;
> > pm_runtime_put_noidle(mmc_dev(host->mmc));
> > }
> > +EXPORT_SYMBOL_GPL(sdhci_runtime_pm_bus_off);
>
> Let's not support SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON for UHS-II
>
I will update it in the patch#10 of the new [PATCH V6].
> >
> > void sdhci_reset(struct sdhci_host *host, u8 mask)
> > {
> > diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> > index bbed850241d4..28716105da61 100644
> > --- a/drivers/mmc/host/sdhci.h
> > +++ b/drivers/mmc/host/sdhci.h
> > @@ -715,6 +715,19 @@ struct sdhci_ops {
> > u8 power_mode);
> > unsigned int (*get_ro)(struct sdhci_host *host);
> > void (*reset)(struct sdhci_host *host, u8 mask);
> > + /**
> > + * The sdhci_uhs2_reset callback is to implement for reset
> > + * @host: SDHCI host
> > + * @mask: Control mask
> > + *
> > + * Invoke reset, depending on a bit in @mask and wait for completion.
> > + * SD mode UHS-II mode
> > + * SDHCI_RESET_ALL SDHCI_UHS2_SW_RESET_FULL
> > + * SDHCI_RESET_CMD SDHCI_RESET_CMD
> > + * SDHCI_RESET_DATA SDHCI_UHS2_SW_RESET_SD
> > + *
> > + **/
> > + void (*uhs2_reset)(struct sdhci_host *host, u16 mask);
>
> This is only being called from sdhci_uhs2.c so let's just call it
> directly for now, instead of using a callback.
>
I will update it in the patch#10 of the new [PATCH V6].
> > int (*platform_execute_tuning)(struct sdhci_host *host, u32 opcode);
> > void (*set_uhs_signaling)(struct sdhci_host *host, unsigned int uhs);
> > void (*hw_reset)(struct sdhci_host *host);
> > @@ -837,6 +850,7 @@ static inline void sdhci_read_caps(struct sdhci_host *host)
> > __sdhci_read_caps(host, NULL, NULL, NULL);
> > }
> >
> > +void sdhci_runtime_pm_bus_off(struct sdhci_host *host);
>
> Let's not support SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON for UHS-II
>
I will update it in the patch#10 of the new [PATCH V6].
> > u16 sdhci_calc_clk(struct sdhci_host *host, unsigned int clock,
> > unsigned int *actual_clock);
> > void sdhci_set_clock(struct sdhci_host *host, unsigned int clock);
>
Thanks, Victor Shih