Re: [RFC PATCH v3.1 16/27] mmc: sdhci-uhs2: add set_ios()

Adrian Hunter
2020-11-26T08:18:03Z

On 6/11/20 4:27 am, AKASHI Takahiro wrote:
> This is a sdhci version of mmc's set_ios operation.
> It covers both UHS-I and UHS-II.
>
> Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> ---
> drivers/mmc/host/sdhci-uhs2.c | 100 ++++++++++++++++++++++++++++++++++
> drivers/mmc/host/sdhci-uhs2.h | 1 +
> drivers/mmc/host/sdhci.c | 40 +++++++++-----
> drivers/mmc/host/sdhci.h | 2 +
> 4 files changed, 128 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> index d9e98c097bfe..637464748cc4 100644
> --- a/drivers/mmc/host/sdhci-uhs2.c
> +++ b/drivers/mmc/host/sdhci-uhs2.c
> @@ -263,6 +263,74 @@ void sdhci_uhs2_set_timeout(struct sdhci_host *host, struct mmc_command *cmd)
> }
> EXPORT_SYMBOL_GPL(sdhci_uhs2_set_timeout);
>
> +/**
> + * sdhci_uhs2_clear_set_irqs - set Error Interrupt Status Enable register
> + * @host: SDHCI host
> + * @clear: bit-wise clear mask
> + * @set: bit-wise set mask
> + *
> + * Set/unset bits in UHS-II Error Interrupt Status Enable register
> + */
> +void sdhci_uhs2_clear_set_irqs(struct sdhci_host *host, u32 clear, u32 set)
> +{
> + u32 ier;
> +
> + ier = sdhci_readl(host, SDHCI_UHS2_ERR_INT_STATUS_EN);
> + ier &= ~clear;
> + ier |= set;
> + sdhci_writel(host, ier, SDHCI_UHS2_ERR_INT_STATUS_EN);
> + sdhci_writel(host, ier, SDHCI_UHS2_ERR_INT_SIG_EN);
> +}
> +EXPORT_SYMBOL_GPL(sdhci_uhs2_clear_set_irqs);
> +
> +static void __sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> +{
> + struct sdhci_host *host = mmc_priv(mmc);
> + u8 cmd_res, dead_lock;
> + u16 ctrl_2;
> + unsigned long flags;
> +
> + /* FIXME: why lock? */
> + spin_lock_irqsave(&host->lock, flags);
> +
> + /* UHS2 Timeout Control */
> + sdhci_calc_timeout_uhs2(host, &cmd_res, &dead_lock);
> +
> + /* change to use calculate value */
> + cmd_res |= dead_lock << SDHCI_UHS2_TIMER_CTRL_DEADLOCK_SHIFT;
> +
> + sdhci_uhs2_clear_set_irqs(host,
> + SDHCI_UHS2_ERR_INT_STATUS_RES_TIMEOUT |
> + SDHCI_UHS2_ERR_INT_STATUS_DEADLOCK_TIMEOUT,
> + 0);
> + sdhci_writeb(host, cmd_res, SDHCI_UHS2_TIMER_CTRL);
> + sdhci_uhs2_clear_set_irqs(host, 0,
> + SDHCI_UHS2_ERR_INT_STATUS_RES_TIMEOUT |
> + SDHCI_UHS2_ERR_INT_STATUS_DEADLOCK_TIMEOUT);
> +
> + /* UHS2 timing */
> + ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> + if (ios->timing == MMC_TIMING_UHS2)
> + ctrl_2 |= SDHCI_CTRL_UHS_2 | SDHCI_CTRL_UHS2_INTERFACE_EN;
> + else
> + ctrl_2 &= ~(SDHCI_CTRL_UHS_2 | SDHCI_CTRL_UHS2_INTERFACE_EN);
> + sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
> +
> + if (!(host->quirks2 & SDHCI_QUIRK2_PRESET_VALUE_BROKEN))
> + sdhci_enable_preset_value(host, true);
> +
> + if (host->ops->set_power)
> + host->ops->set_power(host, ios->power_mode, ios->vdd);
> + else
> + sdhci_set_power(host, ios->power_mode, ios->vdd);
> + udelay(100);
> +
> + host->timing = ios->timing;
> + sdhci_set_clock(host, host->clock);

sdhci_set_ios_common() already called ->set_clock() and ->set_power(), so I
am not really following what is going on here. Can you explain some more?

> +
> + spin_unlock_irqrestore(&host->lock, flags);
> +}
> +
> /*****************************************************************************\
> * *
> * MMC callbacks *
> @@ -286,6 +354,37 @@ static int sdhci_uhs2_start_signal_voltage_switch(struct mmc_host *mmc,
> return sdhci_start_signal_voltage_switch(mmc, ios);
> }
>
> +void sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> +{
> + struct sdhci_host *host = mmc_priv(mmc);
> +
> + if (!(host->version >= SDHCI_SPEC_400) ||
> + !(host->mmc->flags & MMC_UHS2_SUPPORT &&
> + host->mmc->caps & MMC_CAP_UHS2)) {
> + sdhci_set_ios(mmc, ios);
> + return;
> + }
> +
> + if (ios->power_mode == MMC_POWER_UNDEFINED)
> + return;
> +
> + if (host->flags & SDHCI_DEVICE_DEAD) {
> + if (!IS_ERR(mmc->supply.vmmc) &&
> + ios->power_mode == MMC_POWER_OFF)
> + mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
> + if (!IS_ERR_OR_NULL(mmc->supply.vmmc2) &&
> + ios->power_mode == MMC_POWER_OFF)
> + mmc_regulator_set_ocr(mmc, mmc->supply.vmmc2, 0);
> + return;
> + }
> +
> + /* FIXME: host->timing = ios->timing */
> +
> + sdhci_set_ios_common(mmc, ios);
> +
> + __sdhci_uhs2_set_ios(mmc, ios);
> +}
> +
> /*****************************************************************************\
> * *
> * Driver init/exit *
> @@ -296,6 +395,7 @@ static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
> {
> host->mmc_host_ops.start_signal_voltage_switch =
> sdhci_uhs2_start_signal_voltage_switch;
> + host->mmc_host_ops.set_ios = sdhci_uhs2_set_ios;
>
> return 0;
> }
> diff --git a/drivers/mmc/host/sdhci-uhs2.h b/drivers/mmc/host/sdhci-uhs2.h
> index efe70577bc74..c1ff4ac1ab7a 100644
> --- a/drivers/mmc/host/sdhci-uhs2.h
> +++ b/drivers/mmc/host/sdhci-uhs2.h
> @@ -214,5 +214,6 @@ void sdhci_uhs2_reset(struct sdhci_host *host, u16 mask);
> void sdhci_uhs2_set_power(struct sdhci_host *host, unsigned char mode,
> unsigned short vdd);
> void sdhci_uhs2_set_timeout(struct sdhci_host *host, struct mmc_command *cmd);
> +void sdhci_uhs2_clear_set_irqs(struct sdhci_host *host, u32 clear, u32 set);
>
> #endif /* __SDHCI_UHS2_H */
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 0b741eb546cb..becb228330af 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -48,8 +48,6 @@
> static unsigned int debug_quirks = 0;
> static unsigned int debug_quirks2;
>
> -static void sdhci_enable_preset_value(struct sdhci_host *host, bool enable);
> -
> static bool sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd);
>
> void sdhci_dumpregs(struct sdhci_host *host)
> @@ -1836,6 +1834,9 @@ static u16 sdhci_get_preset_value(struct sdhci_host *host)
> case MMC_TIMING_MMC_HS400:
> preset = sdhci_readw(host, SDHCI_PRESET_FOR_HS400);
> break;
> + case MMC_TIMING_UHS2:
> + preset = sdhci_readw(host, SDHCI_PRESET_FOR_UHS2);
> + break;
> default:
> pr_warn("%s: Invalid UHS-I mode selected\n",
> mmc_hostname(host->mmc));
> @@ -2249,20 +2250,9 @@ void sdhci_set_uhs_signaling(struct sdhci_host *host, unsigned timing)
> }
> EXPORT_SYMBOL_GPL(sdhci_set_uhs_signaling);
>
> -void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> +void sdhci_set_ios_common(struct mmc_host *mmc, struct mmc_ios *ios)
> {
> struct sdhci_host *host = mmc_priv(mmc);
> - u8 ctrl;
> -
> - if (ios->power_mode == MMC_POWER_UNDEFINED)
> - return;
> -
> - if (host->flags & SDHCI_DEVICE_DEAD) {
> - if (!IS_ERR(mmc->supply.vmmc) &&
> - ios->power_mode == MMC_POWER_OFF)
> - mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
> - return;
> - }
>
> /*
> * Reset the chip on each power off.
> @@ -2299,6 +2289,25 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> host->ops->set_power(host, ios->power_mode, ios->vdd);
> else
> sdhci_set_power(host, ios->power_mode, ios->vdd);
> +}
> +EXPORT_SYMBOL_GPL(sdhci_set_ios_common);
> +
> +void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> +{
> + struct sdhci_host *host = mmc_priv(mmc);
> + u8 ctrl;
> +
> + if (ios->power_mode == MMC_POWER_UNDEFINED)
> + return;
> +
> + if (host->flags & SDHCI_DEVICE_DEAD) {
> + if (!IS_ERR(mmc->supply.vmmc) &&
> + ios->power_mode == MMC_POWER_OFF)
> + mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
> + return;
> + }
> +
> + sdhci_set_ios_common(mmc, ios);
>
> if (host->ops->platform_send_init_74_clocks)
> host->ops->platform_send_init_74_clocks(host, ios->power_mode);
> @@ -2869,7 +2878,7 @@ int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)
> }
> EXPORT_SYMBOL_GPL(sdhci_execute_tuning);
>
> -static void sdhci_enable_preset_value(struct sdhci_host *host, bool enable)
> +void sdhci_enable_preset_value(struct sdhci_host *host, bool enable)
> {
> /* Host Controller v3.00 defines preset value registers */
> if (host->version < SDHCI_SPEC_300)
> @@ -2897,6 +2906,7 @@ static void sdhci_enable_preset_value(struct sdhci_host *host, bool enable)
> host->preset_enabled = enable;
> }
> }
> +EXPORT_SYMBOL_GPL(sdhci_enable_preset_value);
>
> static void sdhci_post_req(struct mmc_host *mmc, struct mmc_request *mrq,
> int err)
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index 2b5b8295cf92..e84ebddb20d8 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -851,6 +851,8 @@ void sdhci_set_bus_width(struct sdhci_host *host, int width);
> void sdhci_reset(struct sdhci_host *host, u8 mask);
> void sdhci_set_uhs_signaling(struct sdhci_host *host, unsigned timing);
> int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode);
> +void sdhci_enable_preset_value(struct sdhci_host *host, bool enable);
> +void sdhci_set_ios_common(struct mmc_host *mmc, struct mmc_ios *ios);
> void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios);
> int sdhci_start_signal_voltage_switch(struct mmc_host *mmc,
> struct mmc_ios *ios);
>