Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1258008

[PATCH v6 14/15] scsi: ufs: commit descriptors before setting the doorbell

Show all headers | View raw

Add a write memory barrier to make sure descriptors prepared are actually
written to memory before ringing the doorbell. We have also added the
write memory barrier after ringing the doorbell register so that
controller sees the new request immediately.

Reviewed-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Gilad Broner <gbroner@codeaurora.org>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>

---
 drivers/scsi/ufs/ufshcd.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index dfc4ac1..ec90504 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -1628,6 +1628,8 @@ static int ufshcd_exec_dev_cmd(struct ufs_hba *hba,
 
 	hba->dev_cmd.complete = &wait;
 
+	/* Make sure descriptors are ready before ringing the doorbell */
+	wmb();
 	spin_lock_irqsave(hba->host->host_lock, flags);
 	ufshcd_send_command(hba, tag);
 	spin_unlock_irqrestore(hba->host->host_lock, flags);
-- 
1.8.5.2

-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH v6 00/15] Big fixes, retries, handle a race condition Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
  [PATCH v6 13/15] scsi: ufs: add missing memory barriers Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
  [PATCH v6 08/15] scsi: ufs: add retries to dme_peer get and set attribute Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
  [PATCH v6 12/15] scsi: ufs: reduce the interrupts for power mode change requests Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
  [PATCH v6 04/15] scsi: ufs: clear outstanding_request bit in case query timeout Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
  [PATCH v6 01/15] scsi: ufs: clear UTRD, UPIU req and rsp before new transfers Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
  [PATCH v6 15/15] scsi: ufs: add wrapper for retrying sending query attribute Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
  [PATCH v6 11/15] scsi: ufs: retry failed query flag requests Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
  [PATCH v6 14/15] scsi: ufs: commit descriptors before setting the doorbell Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
  [PATCH v6 06/15] scsi: ufs: avoid exception event handler racing with PM callbacks Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
  [PATCH v6 07/15] scsi: ufs: set REQUEST_SENSE command size to 18 bytes Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
    Re: [PATCH v6 07/15] scsi: ufs: set REQUEST_SENSE command size to 18  bytes Hannes Reinecke <hare@suse.de> - 2015-10-30 13:20 +0100
  [PATCH v6 03/15] scsi: ufs: verify command tag validity Yaniv Gardi <ygardi@codeaurora.org> - 2015-10-28 14:20 +0100
  Re: [PATCH v6 00/15] Big fixes, retries, handle a race condition Hannes Reinecke <hare@suse.de> - 2015-10-30 13:30 +0100

csiph-web