Commit da4bc4f2 authored by Adrian Hunter's avatar Adrian Hunter Committed by Ulf Hansson
Browse files

mmc: sdhci: Factor out tuning helper functions 



Factor out some functions to tidy up the code in sdhci_execute_tuning.

Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent d0c3ab59

drivers/mmc/host/sdhci.c

+124 −92
Original line number Diff line number Diff line
@@ -1952,64 +1952,9 @@ static int sdhci_prepare_hs400_tuning(struct mmc_host *mmc, struct mmc_ios *ios) 
	return 0;

}



static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)

static void sdhci_start_tuning(struct sdhci_host *host)

{

	struct sdhci_host *host = mmc_priv(mmc);

	u16 ctrl;

	int tuning_loop_counter = MAX_TUNING_LOOP;

	int err = 0;

	unsigned long flags;

	unsigned int tuning_count = 0;

	bool hs400_tuning;



	spin_lock_irqsave(&host->lock, flags);



	hs400_tuning = host->flags & SDHCI_HS400_TUNING;

	host->flags &= ~SDHCI_HS400_TUNING;



	if (host->tuning_mode == SDHCI_TUNING_MODE_1)

		tuning_count = host->tuning_count;



	/*

	 * The Host Controller needs tuning in case of SDR104 and DDR50

	 * mode, and for SDR50 mode when Use Tuning for SDR50 is set in

	 * the Capabilities register.

	 * If the Host Controller supports the HS200 mode then the

	 * tuning function has to be executed.

	 */

	switch (host->timing) {

	/* HS400 tuning is done in HS200 mode */

	case MMC_TIMING_MMC_HS400:

		err = -EINVAL;

		goto out_unlock;



	case MMC_TIMING_MMC_HS200:

		/*

		 * Periodic re-tuning for HS400 is not expected to be needed, so

		 * disable it here.

		 */

		if (hs400_tuning)

			tuning_count = 0;

		break;



	case MMC_TIMING_UHS_SDR104:

	case MMC_TIMING_UHS_DDR50:

		break;



	case MMC_TIMING_UHS_SDR50:

		if (host->flags & SDHCI_SDR50_NEEDS_TUNING)

			break;

		/* FALLTHROUGH */



	default:

		goto out_unlock;

	}



	if (host->ops->platform_execute_tuning) {

		spin_unlock_irqrestore(&host->lock, flags);

		err = host->ops->platform_execute_tuning(host, opcode);

		return err;

	}



	ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);

	ctrl |= SDHCI_CTRL_EXEC_TUNING;
@@ -2029,28 +1974,58 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) 
	 */

	sdhci_writel(host, SDHCI_INT_DATA_AVAIL, SDHCI_INT_ENABLE);

	sdhci_writel(host, SDHCI_INT_DATA_AVAIL, SDHCI_SIGNAL_ENABLE);

}



static void sdhci_end_tuning(struct sdhci_host *host)

{

	sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);

	sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);

}



static void sdhci_reset_tuning(struct sdhci_host *host)

{

	u16 ctrl;



	ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);

	ctrl &= ~SDHCI_CTRL_TUNED_CLK;

	ctrl &= ~SDHCI_CTRL_EXEC_TUNING;

	sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);

}



static void sdhci_abort_tuning(struct sdhci_host *host, u32 opcode,

			       unsigned long flags)

{

	sdhci_reset_tuning(host);



	sdhci_do_reset(host, SDHCI_RESET_CMD);

	sdhci_do_reset(host, SDHCI_RESET_DATA);



	sdhci_end_tuning(host);



	spin_unlock_irqrestore(&host->lock, flags);

	mmc_abort_tuning(host->mmc, opcode);

	spin_lock_irqsave(&host->lock, flags);

}



/*

	 * Issue CMD19 repeatedly till Execute Tuning is set to 0 or the number

	 * of loops reaches 40 times.

 * We use sdhci_send_tuning() because mmc_send_tuning() is not a good fit. SDHCI

 * tuning command does not have a data payload (or rather the hardware does it

 * automatically) so mmc_send_tuning() will return -EIO. Also the tuning command

 * interrupt setup is different to other commands and there is no timeout

 * interrupt so special handling is needed.

 */

	do {

static void sdhci_send_tuning(struct sdhci_host *host, u32 opcode,

			      unsigned long flags)

{

	struct mmc_host *mmc = host->mmc;

	struct mmc_command cmd = {0};

	struct mmc_request mrq = {NULL};



	cmd.opcode = opcode;

		cmd.arg = 0;

	cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;

		cmd.retries = 0;

		cmd.data = NULL;

	cmd.mrq = &mrq;

		cmd.error = 0;



		if (tuning_loop_counter-- == 0)

			break;



	mrq.cmd = &cmd;



	/*

	 * In response to CMD19, the card sends 64 bytes of tuning

	 * block to the Host Controller. So we set the block size
@@ -2079,37 +2054,97 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) 
	sdhci_send_command(host, &cmd);



	host->cmd = NULL;



	sdhci_del_timer(host, &mrq);



	host->tuning_done = 0;



	spin_unlock_irqrestore(&host->lock, flags);



	/* Wait for Buffer Read Ready interrupt */

		wait_event_timeout(host->buf_ready_int,

					(host->tuning_done == 1),

	wait_event_timeout(host->buf_ready_int, (host->tuning_done == 1),

			   msecs_to_jiffies(50));



	spin_lock_irqsave(&host->lock, flags);

}



		if (!host->tuning_done) {

			pr_info(DRIVER_NAME ": Timeout waiting for Buffer Read Ready interrupt during tuning procedure, falling back to fixed sampling clock\n");

			ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);

			ctrl &= ~SDHCI_CTRL_TUNED_CLK;

			ctrl &= ~SDHCI_CTRL_EXEC_TUNING;

			sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);

static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)

{

	struct sdhci_host *host = mmc_priv(mmc);

	u16 ctrl;

	int tuning_loop_counter = MAX_TUNING_LOOP;

	int err = 0;

	unsigned long flags;

	unsigned int tuning_count = 0;

	bool hs400_tuning;



			sdhci_do_reset(host, SDHCI_RESET_CMD);

			sdhci_do_reset(host, SDHCI_RESET_DATA);

	spin_lock_irqsave(&host->lock, flags);



			sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);

			sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);

	hs400_tuning = host->flags & SDHCI_HS400_TUNING;

	host->flags &= ~SDHCI_HS400_TUNING;



	if (host->tuning_mode == SDHCI_TUNING_MODE_1)

		tuning_count = host->tuning_count;



	/*

	 * The Host Controller needs tuning in case of SDR104 and DDR50

	 * mode, and for SDR50 mode when Use Tuning for SDR50 is set in

	 * the Capabilities register.

	 * If the Host Controller supports the HS200 mode then the

	 * tuning function has to be executed.

	 */

	switch (host->timing) {

	/* HS400 tuning is done in HS200 mode */

	case MMC_TIMING_MMC_HS400:

		err = -EINVAL;

		goto out_unlock;



	case MMC_TIMING_MMC_HS200:

		/*

		 * Periodic re-tuning for HS400 is not expected to be needed, so

		 * disable it here.

		 */

		if (hs400_tuning)

			tuning_count = 0;

		break;



	case MMC_TIMING_UHS_SDR104:

	case MMC_TIMING_UHS_DDR50:

		break;



	case MMC_TIMING_UHS_SDR50:

		if (host->flags & SDHCI_SDR50_NEEDS_TUNING)

			break;

		/* FALLTHROUGH */



	default:

		goto out_unlock;

	}



	if (host->ops->platform_execute_tuning) {

		spin_unlock_irqrestore(&host->lock, flags);

			mmc_abort_tuning(mmc, opcode);

			spin_lock_irqsave(&host->lock, flags);

		err = host->ops->platform_execute_tuning(host, opcode);

		return err;

	}



	sdhci_start_tuning(host);



	/*

	 * Issue CMD19 repeatedly till Execute Tuning is set to 0 or the number

	 * of loops reaches 40 times.

	 */

	do {

		if (tuning_loop_counter-- == 0)

			break;



		sdhci_send_tuning(host, opcode, flags);



		if (!host->tuning_done) {

			pr_info(DRIVER_NAME ": Timeout waiting for Buffer Read Ready interrupt during tuning procedure, falling back to fixed sampling clock\n");

			sdhci_abort_tuning(host, opcode, flags);

			goto out;

		}



		host->tuning_done = 0;



		ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);



		/* eMMC spec does not require a delay between tuning cycles */
@@ -2121,18 +2156,15 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) 
	 * The Host Driver has exhausted the maximum number of loops allowed,

	 * so use fixed sampling frequency.

	 */

	if (tuning_loop_counter < 0) {

		ctrl &= ~SDHCI_CTRL_TUNED_CLK;

		ctrl &= ~SDHCI_CTRL_EXEC_TUNING;

		sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);

	}

	if (!(ctrl & SDHCI_CTRL_TUNED_CLK))

	if (tuning_loop_counter < 0)

		sdhci_reset_tuning(host);



	if (tuning_loop_counter < 0 || !(ctrl & SDHCI_CTRL_TUNED_CLK))

		pr_info(DRIVER_NAME ": Tuning procedure failed, falling back to fixed sampling clock\n");

out:

	host->mmc->retune_period = tuning_count;



	sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);

	sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);

	sdhci_end_tuning(host);

out_unlock:

	spin_unlock_irqrestore(&host->lock, flags);

	return err;