Re: [PATCH 3/3] mmc: Checking BKOPS status prior to Suspend

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 2017/1/17 20:15, Uri Yanai wrote:
If asked to do device Runtime Suspend while
in BKOPS and auto BKOPS is enabled return –EBUSY


The commit msg isn't correct as the code just return -EBUSY
when the level of BKOPS is EXT_CSD_BKOPS_LEVEL_PM_SUSPEND.

And how do you decide that EXT_CSD_BKOPS_LEVEL_2 should be used.
From the spec, it means "performance being impacted". It would be
good to know a bit details inside the eMMC firmware.

BTW, should we use EXT_CSD_BKOPS_LEVEL_2 directly since it looks
more strightforward?


Change-Id: Ie4b38a32fe98179f0bca5b57edaaa47a02d0a389
Signed-off-by: Uri Yanai <uri.yanai@xxxxxxxxxxx>
Signed-off-by: Alex Lemberg <alex.lemberg@xxxxxxxxxxx>
---
 drivers/mmc/core/mmc.c  | 35 ++++++++++++++++++++++++++++-------
 include/linux/mmc/mmc.h |  2 ++
 2 files changed, 30 insertions(+), 7 deletions(-)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index f70f6a1..21f5851 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1942,7 +1942,8 @@ static void mmc_detect(struct mmc_host *host)
 	}
 }

-static int _mmc_suspend(struct mmc_host *host, bool is_suspend)
+static int _mmc_suspend(struct mmc_host *host, bool is_suspend,
+	bool is_runtime_pm)
 {
 	int err = 0;
 	unsigned int notify_type = is_suspend ? EXT_CSD_POWER_OFF_SHORT :
@@ -1953,10 +1954,30 @@ static int _mmc_suspend(struct mmc_host *host, bool is_suspend)
 	if (mmc_card_suspended(host->card))
 		goto out;

-	if (mmc_card_doing_bkops(host->card)) {
-		err = mmc_stop_bkops(host->card);
-		if (err)
+	if (mmc_card_doing_bkops(host->card) ||
+		host->card->ext_csd.auto_bkops_en) {
+		err = mmc_read_bkops_status(host->card);
+		if (err) {
+			pr_err("%s: error %d reading BKOPS Status\n",
+				mmc_hostname(host), err);
 			goto out;
+		}
+		if (is_runtime_pm && host->card->ext_csd.raw_bkops_status >=
+				EXT_CSD_BKOPS_LEVEL_PM_SUSPEND) {
+			/*
+			 * We don’t allow Runtime Suspend while device still
+			 * needs time to complete internal BKOPS, returning
+			 * -EBUSY while BKOPS level is above
+			 *  EXT_CSD_BKOPS_LEVEL_PM_SUSPEND
+			 */
+			err = -EBUSY;
+			goto out;
+		}
+		if (mmc_card_doing_bkops(host->card)) {
+			err = mmc_stop_bkops(host->card);
+			if (err)
+				goto out;
+		}
 	}

 	err = mmc_flush_cache(host->card);
@@ -1987,7 +2008,7 @@ static int mmc_suspend(struct mmc_host *host)
 {
 	int err;

-	err = _mmc_suspend(host, true);
+	err = _mmc_suspend(host, true, false);
 	if (!err) {
 		pm_runtime_disable(&host->card->dev);
 		pm_runtime_set_suspended(&host->card->dev);
@@ -2034,7 +2055,7 @@ static int mmc_shutdown(struct mmc_host *host)
 		err = _mmc_resume(host);

 	if (!err)
-		err = _mmc_suspend(host, false);
+		err = _mmc_suspend(host, false, false);

 	return err;
 }
@@ -2058,7 +2079,7 @@ static int mmc_runtime_suspend(struct mmc_host *host)
 	if (!(host->caps & MMC_CAP_AGGRESSIVE_PM))
 		return 0;

-	err = _mmc_suspend(host, true);
+	err = _mmc_suspend(host, true, true);
 	if (err)
 		pr_err("%s: error %d doing aggressive suspend\n",
 			mmc_hostname(host), err);
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index 126b8d5..2633274 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -445,6 +445,8 @@ struct _mmc_csd {
  */
 #define EXT_CSD_BKOPS_LEVEL_2		0x2

+#define EXT_CSD_BKOPS_LEVEL_PM_SUSPEND	EXT_CSD_BKOPS_LEVEL_2
+
 /*
  * BKOPS modes
  */



--
Best Regards
Shawn Lin

--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux USB Devel]     [Linux Media]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux