Re: [PATCH V5 15/26] mmc: sdhci-uhs2: add set_ios()

[Adrian Hunter <adrian.hunter@intel.com>]

On 19/10/22 14:06, Victor Shih 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>
> Signed-off-by: Victor Shih <victor.shih@genesyslogic.com.tw>
> ---
>  drivers/mmc/host/sdhci-uhs2.c | 102 ++++++++++++++++++++++++++++++++++
>  drivers/mmc/host/sdhci-uhs2.h |   1 +
>  drivers/mmc/host/sdhci.c      |  40 ++++++++-----
>  drivers/mmc/host/sdhci.h      |   2 +
>  4 files changed, 130 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> index 2b90e5308764..b535a47dc55a 100644
> --- a/drivers/mmc/host/sdhci-uhs2.c
> +++ b/drivers/mmc/host/sdhci-uhs2.c
> @@ -281,6 +281,74 @@ 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_set_ios() should not be racing with anything, so the lock
should not be needed.  Please remove for now.

> +
> +	/* 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_SD_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_uhs2_set_power(host, ios->power_mode, ios->vdd);
> +	udelay(100);
> +
> +	host->timing = ios->timing;
> +	sdhci_set_clock(host, host->clock);
> +
> +	spin_unlock_irqrestore(&host->lock, flags);
> +}
> +
>  /*****************************************************************************\
>   *                                                                           *
>   * MMC callbacks                                                             *
> @@ -302,6 +370,39 @@ static int sdhci_uhs2_start_signal_voltage_switch(struct mmc_host *mmc,
>  	return sdhci_start_signal_voltage_switch(mmc, ios);
>  }
>  
> +int 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->caps2 & MMC_CAP2_SD_UHS2)) {
> +		sdhci_set_ios(mmc, ios);
> +		return 0;
> +	}
> +
> +	if (ios->power_mode == MMC_POWER_UNDEFINED)
> +		return 1;

->uhs2_set_ios() expects 0 or a negative error code.
This case is not an error.

		return 0;

> +
> +	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 1;

This is an error, so a negative code is needed

> +	}
> +
> +	/* FIXME: host->timing = ios->timing */

Yes, __sdhci_uhs2_set_ios() should do that when it sets the timing

> +
> +	sdhci_set_ios_common(mmc, ios);
> +
> +	__sdhci_uhs2_set_ios(mmc, ios);
> +
> +	return 0;
> +}
> +
>  /*****************************************************************************\
>   *                                                                           *
>   * Driver init/exit                                                          *
> @@ -312,6 +413,7 @@ 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.uhs2_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 5ea235b14108..23368448ccd4 100644
> --- a/drivers/mmc/host/sdhci-uhs2.h
> +++ b/drivers/mmc/host/sdhci-uhs2.h
> @@ -216,5 +216,6 @@ 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 dfa0939a9058..de47c71995fb 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -47,8 +47,6 @@
>  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)
> @@ -1888,6 +1886,9 @@ 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_SD_UHS2:
> +		preset = sdhci_readw(host, SDHCI_PRESET_FOR_UHS2);
> +		break;
>  	default:
>  		pr_warn("%s: Invalid UHS-I mode selected\n",
>  			mmc_hostname(host->mmc));
> @@ -2305,20 +2306,9 @@ 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.
> @@ -2355,6 +2345,25 @@ 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);
> @@ -2935,7 +2944,7 @@ 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)
> @@ -2963,6 +2972,7 @@ 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 c34ca6ffbff6..22d7f47862ae 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -871,6 +871,8 @@ 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);