Commit 8266c585 authored by Ludovic Barre's avatar Ludovic Barre Committed by Ulf Hansson
Browse files

mmc: mmci: add hardware busy timeout feature 



In the stm32_sdmmc variant, the datatimer is active not only during
data transfers with the DPSM, but also while waiting for the busyend
IRQs from commands having the MMC_RSP_BUSY flag set. This leads to an
incorrect IRQ being raised to signal MCI_DATATIMEOUT error, which
simply breaks the behaviour.

Address this by updating the datatimer value before sending a command
having the MMC_RSP_BUSY flag set. To inform the mmc core about the
maximum supported busy timeout, which also depends on the current
clock rate, set ->max_busy_timeout (in ms).

Signed-off-by: default avatarLudovic Barre <ludovic.barre@st.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent e2b98d83

drivers/mmc/host/mmci.c

+37 −5
Original line number Original line Diff line number Diff line
@@ -1075,6 +1075,7 @@ static void 
mmci_start_command(struct mmci_host *host, struct mmc_command *cmd, u32 c)

mmci_start_command(struct mmci_host *host, struct mmc_command *cmd, u32 c)

{

{

	void __iomem *base = host->base;

	void __iomem *base = host->base;

	unsigned long long clks;





	dev_dbg(mmc_dev(host->mmc), "op %02x arg %08x flags %08x\n",

	dev_dbg(mmc_dev(host->mmc), "op %02x arg %08x flags %08x\n",

	    cmd->opcode, cmd->arg, cmd->flags);

	    cmd->opcode, cmd->arg, cmd->flags);
@@ -1097,6 +1098,16 @@ mmci_start_command(struct mmci_host *host, struct mmc_command *cmd, u32 c) 
		else

		else

			c |= host->variant->cmdreg_srsp;

			c |= host->variant->cmdreg_srsp;

	}

	}



	if (host->variant->busy_timeout && cmd->flags & MMC_RSP_BUSY) {

		if (!cmd->busy_timeout)

			cmd->busy_timeout = 10 * MSEC_PER_SEC;



		clks = (unsigned long long)cmd->busy_timeout * host->cclk;

		do_div(clks, MSEC_PER_SEC);

		writel_relaxed(clks, host->base + MMCIDATATIMER);

	}



	if (/*interrupt*/0)

	if (/*interrupt*/0)

		c |= MCI_CPSM_INTERRUPT;

		c |= MCI_CPSM_INTERRUPT;
@@ -1201,6 +1212,7 @@ static void 
mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd,

mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd,

	     unsigned int status)

	     unsigned int status)

{

{

	u32 err_msk = MCI_CMDCRCFAIL | MCI_CMDTIMEOUT;

	void __iomem *base = host->base;

	void __iomem *base = host->base;

	bool sbc, busy_resp;

	bool sbc, busy_resp;
@@ -1215,8 +1227,11 @@ mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd, 
	 * handling. Note that we tag on any latent IRQs postponed

	 * handling. Note that we tag on any latent IRQs postponed

	 * due to waiting for busy status.

	 * due to waiting for busy status.

	 */

	 */

	if (host->variant->busy_timeout && busy_resp)

		err_msk |= MCI_DATATIMEOUT;



	if (!((status | host->busy_status) &

	if (!((status | host->busy_status) &

	      (MCI_CMDCRCFAIL|MCI_CMDTIMEOUT|MCI_CMDSENT|MCI_CMDRESPEND)))

	      (err_msk | MCI_CMDSENT | MCI_CMDRESPEND)))

		return;

		return;





	/* Handle busy detection on DAT0 if the variant supports it. */

	/* Handle busy detection on DAT0 if the variant supports it. */
@@ -1235,8 +1250,7 @@ mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd, 
		 * while, to allow it to be set, but tests indicates that it

		 * while, to allow it to be set, but tests indicates that it

		 * isn't needed.

		 * isn't needed.

		 */

		 */

		if (!host->busy_status &&

		if (!host->busy_status && !(status & err_msk) &&

		    !(status & (MCI_CMDCRCFAIL|MCI_CMDTIMEOUT)) &&

		    (readl(base + MMCISTATUS) & host->variant->busy_detect_flag)) {

		    (readl(base + MMCISTATUS) & host->variant->busy_detect_flag)) {





			writel(readl(base + MMCIMASK0) |

			writel(readl(base + MMCIMASK0) |
@@ -1290,6 +1304,9 @@ mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd, 
		cmd->error = -ETIMEDOUT;

		cmd->error = -ETIMEDOUT;

	} else if (status & MCI_CMDCRCFAIL && cmd->flags & MMC_RSP_CRC) {

	} else if (status & MCI_CMDCRCFAIL && cmd->flags & MMC_RSP_CRC) {

		cmd->error = -EILSEQ;

		cmd->error = -EILSEQ;

	} else if (host->variant->busy_timeout && busy_resp &&

		   status & MCI_DATATIMEOUT) {

		cmd->error = -ETIMEDOUT;

	} else {

	} else {

		cmd->resp[0] = readl(base + MMCIRESPONSE0);

		cmd->resp[0] = readl(base + MMCIRESPONSE0);

		cmd->resp[1] = readl(base + MMCIRESPONSE1);

		cmd->resp[1] = readl(base + MMCIRESPONSE1);
@@ -1583,6 +1600,20 @@ static void mmci_request(struct mmc_host *mmc, struct mmc_request *mrq) 
	spin_unlock_irqrestore(&host->lock, flags);

	spin_unlock_irqrestore(&host->lock, flags);

}

}





static void mmci_set_max_busy_timeout(struct mmc_host *mmc)

{

	struct mmci_host *host = mmc_priv(mmc);

	u32 max_busy_timeout = 0;



	if (!host->variant->busy_detect)

		return;



	if (host->variant->busy_timeout && mmc->actual_clock)

		max_busy_timeout = ~0UL / (mmc->actual_clock / MSEC_PER_SEC);



	mmc->max_busy_timeout = max_busy_timeout;

}



static void mmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)

static void mmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)

{

{

	struct mmci_host *host = mmc_priv(mmc);

	struct mmci_host *host = mmc_priv(mmc);
@@ -1687,6 +1718,8 @@ static void mmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) 
	else

	else

		mmci_set_clkreg(host, ios->clock);

		mmci_set_clkreg(host, ios->clock);





	mmci_set_max_busy_timeout(mmc);



	if (host->ops && host->ops->set_pwrreg)

	if (host->ops && host->ops->set_pwrreg)

		host->ops->set_pwrreg(host, pwr);

		host->ops->set_pwrreg(host, pwr);

	else

	else
@@ -1957,7 +1990,6 @@ static int mmci_probe(struct amba_device *dev, 
			mmci_write_datactrlreg(host,

			mmci_write_datactrlreg(host,

					       host->variant->busy_dpsm_flag);

					       host->variant->busy_dpsm_flag);

		mmc->caps |= MMC_CAP_WAIT_WHILE_BUSY;

		mmc->caps |= MMC_CAP_WAIT_WHILE_BUSY;

		mmc->max_busy_timeout = 0;

	}

	}





	/* Prepare a CMD12 - needed to clear the DPSM on some variants. */

	/* Prepare a CMD12 - needed to clear the DPSM on some variants. */

drivers/mmc/host/mmci.h

+3 −0
Original line number Original line Diff line number Diff line
@@ -287,6 +287,8 @@ struct mmci_host; 
 * @signal_direction: input/out direction of bus signals can be indicated

 * @signal_direction: input/out direction of bus signals can be indicated

 * @pwrreg_clkgate: MMCIPOWER register must be used to gate the clock

 * @pwrreg_clkgate: MMCIPOWER register must be used to gate the clock

 * @busy_detect: true if the variant supports busy detection on DAT0.

 * @busy_detect: true if the variant supports busy detection on DAT0.

 * @busy_timeout: true if the variant starts data timer when the DPSM

 *		  enter in Wait_R or Busy state.

 * @busy_dpsm_flag: bitmask enabling busy detection in the DPSM

 * @busy_dpsm_flag: bitmask enabling busy detection in the DPSM

 * @busy_detect_flag: bitmask identifying the bit in the MMCISTATUS register

 * @busy_detect_flag: bitmask identifying the bit in the MMCISTATUS register

 *		      indicating that the card is busy

 *		      indicating that the card is busy
@@ -333,6 +335,7 @@ struct variant_data { 
	u8			signal_direction:1;

	u8			signal_direction:1;

	u8			pwrreg_clkgate:1;

	u8			pwrreg_clkgate:1;

	u8			busy_detect:1;

	u8			busy_detect:1;

	u8			busy_timeout:1;

	u32			busy_dpsm_flag;

	u32			busy_dpsm_flag;

	u32			busy_detect_flag;

	u32			busy_detect_flag;

	u32			busy_detect_mask;

	u32			busy_detect_mask;

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