Commit 0d84c3e6 authored by Ulf Hansson's avatar Ulf Hansson
Browse files

mmc: core: Convert to mmc_poll_for_busy() for erase/trim/discard 



Rather than open coding the polling loop in mmc_do_erase(), let's convert
to use mmc_poll_for_busy().

To allow a slightly different error parsing during polling, compared to the
__mmc_switch() case, a new in-parameter to mmc_poll_for_busy() is needed,
but other than that the conversion is straight forward.

Besides addressing the open coding issue, moving to mmc_poll_for_busy() for
erase/trim/discard improves the behaviour according to below.

- Adds support for polling via the optional ->card_busy() host ops.
- Returns zero to indicate success when the final polling attempt finds the
  card non-busy, even if the timeout expired.
- Exits the polling loop when state moves to R1_STATE_TRAN, rather than
  when leaving R1_STATE_PRG.
- Decreases the starting range for throttling to 32-64us.

Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Tested-by: default avatarBaolin Wang <baolin.wang7@gmail.com>
Tested-by: default avatarLudovic Barre <ludovic.barre@st.com>
Reviewed-by: default avatarLudovic Barre <ludovic.barre@st.com>
Link: https://lore.kernel.org/r/20200204085449.32585-9-ulf.hansson@linaro.org
parent 2a1c7cda

drivers/mmc/core/core.c

+2 −34
Original line number Diff line number Diff line
@@ -1658,8 +1658,6 @@ static int mmc_do_erase(struct mmc_card *card, unsigned int from, 
	struct mmc_command cmd = {};

	unsigned int qty = 0, busy_timeout = 0;

	bool use_r1b_resp = false;

	unsigned long timeout;

	int loop_udelay=64, udelay_max=32768;

	int err;



	mmc_retune_hold(card->host);
@@ -1763,38 +1761,8 @@ static int mmc_do_erase(struct mmc_card *card, unsigned int from, 
	if ((card->host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp)

		goto out;



	timeout = jiffies + msecs_to_jiffies(busy_timeout);

	do {

		memset(&cmd, 0, sizeof(struct mmc_command));

		cmd.opcode = MMC_SEND_STATUS;

		cmd.arg = card->rca << 16;

		cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;

		/* Do not retry else we can't see errors */

		err = mmc_wait_for_cmd(card->host, &cmd, 0);

		if (err || R1_STATUS(cmd.resp[0])) {

			pr_err("error %d requesting status %#x\n",

				err, cmd.resp[0]);

			err = -EIO;

			goto out;

		}



		/* Timeout if the device never becomes ready for data and

		 * never leaves the program state.

		 */

		if (time_after(jiffies, timeout)) {

			pr_err("%s: Card stuck in programming state! %s\n",

				mmc_hostname(card->host), __func__);

			err =  -EIO;

			goto out;

		}

		if ((cmd.resp[0] & R1_READY_FOR_DATA) &&

		    R1_CURRENT_STATE(cmd.resp[0]) != R1_STATE_PRG)

			break;



		usleep_range(loop_udelay, loop_udelay*2);

		if (loop_udelay < udelay_max)

			loop_udelay *= 2;

	} while (1);

	/* Let's poll to find out when the erase operation completes. */

	err = mmc_poll_for_busy(card, busy_timeout, MMC_BUSY_ERASE);



out:

	mmc_retune_release(card->host);

drivers/mmc/core/mmc_ops.c

+24 −6
Original line number Diff line number Diff line
@@ -445,7 +445,7 @@ int mmc_switch_status(struct mmc_card *card, bool crc_err_fatal) 
}



static int mmc_busy_status(struct mmc_card *card, bool retry_crc_err,

			   bool *busy)

			   enum mmc_busy_cmd busy_cmd, bool *busy)

{

	struct mmc_host *host = card->host;

	u32 status = 0;
@@ -464,7 +464,17 @@ static int mmc_busy_status(struct mmc_card *card, bool retry_crc_err, 
	if (err)

		return err;



	switch (busy_cmd) {

	case MMC_BUSY_CMD6:

		err = mmc_switch_status_error(card->host, status);

		break;

	case MMC_BUSY_ERASE:

		err = R1_STATUS(status) ? -EIO : 0;

		break;

	default:

		err = -EINVAL;

	}



	if (err)

		return err;
@@ -472,8 +482,9 @@ static int mmc_busy_status(struct mmc_card *card, bool retry_crc_err, 
	return 0;

}



static int mmc_poll_for_busy(struct mmc_card *card, unsigned int timeout_ms,

			bool send_status, bool retry_crc_err)

static int __mmc_poll_for_busy(struct mmc_card *card, unsigned int timeout_ms,

			       bool send_status, bool retry_crc_err,

			       enum mmc_busy_cmd busy_cmd)

{

	struct mmc_host *host = card->host;

	int err;
@@ -500,7 +511,7 @@ static int mmc_poll_for_busy(struct mmc_card *card, unsigned int timeout_ms, 
		 */

		expired = time_after(jiffies, timeout);



		err = mmc_busy_status(card, retry_crc_err, &busy);

		err = mmc_busy_status(card, retry_crc_err, busy_cmd, &busy);

		if (err)

			return err;
@@ -522,6 +533,12 @@ static int mmc_poll_for_busy(struct mmc_card *card, unsigned int timeout_ms, 
	return 0;

}



int mmc_poll_for_busy(struct mmc_card *card, unsigned int timeout_ms,

		      enum mmc_busy_cmd busy_cmd)

{

	return __mmc_poll_for_busy(card, timeout_ms, true, false, busy_cmd);

}



/**

 *	__mmc_switch - modify EXT_CSD register

 *	@card: the MMC card associated with the data transfer
@@ -591,7 +608,8 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value, 
		goto out_tim;



	/* Let's try to poll to find out when the command is completed. */

	err = mmc_poll_for_busy(card, timeout_ms, send_status, retry_crc_err);

	err = __mmc_poll_for_busy(card, timeout_ms, send_status, retry_crc_err,

				  MMC_BUSY_CMD6);

	if (err)

		goto out;

drivers/mmc/core/mmc_ops.h

+7 −0
Original line number Diff line number Diff line
@@ -10,6 +10,11 @@ 


#include <linux/types.h>



enum mmc_busy_cmd {

	MMC_BUSY_CMD6,

	MMC_BUSY_ERASE,

};



struct mmc_host;

struct mmc_card;
@@ -30,6 +35,8 @@ int mmc_interrupt_hpi(struct mmc_card *card); 
int mmc_can_ext_csd(struct mmc_card *card);

int mmc_get_ext_csd(struct mmc_card *card, u8 **new_ext_csd);

int mmc_switch_status(struct mmc_card *card, bool crc_err_fatal);

int mmc_poll_for_busy(struct mmc_card *card, unsigned int timeout_ms,

		      enum mmc_busy_cmd busy_cmd);

int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,

		unsigned int timeout_ms, unsigned char timing,

		bool send_status, bool retry_crc_err);

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