[PATCH 17/20] scsi/qla1280: Remove stale comment about mmiowb()

Will Deacon
2019-03-01T14:05:09Z

All mmiowb() invocations have been removed, so there's no need to keep
banging on about it.

Signed-off-by: Will Deacon <will.deacon@arm.com>
---
drivers/scsi/qla1280.c | 10 ----------
1 file changed, 10 deletions(-)

diff --git a/drivers/scsi/qla1280.c b/drivers/scsi/qla1280.c
index 93acbc5094f0..327eff67a1ee 100644
--- a/drivers/scsi/qla1280.c
+++ b/drivers/scsi/qla1280.c
@@ -3363,16 +3363,6 @@ qla1280_isp_cmd(struct scsi_qla_host *ha)

/*
* Update request index to mailbox4 (Request Queue In).
- * The mmiowb() ensures that this write is ordered with writes by other
- * CPUs. Without the mmiowb(), it is possible for the following:
- * CPUA posts write of index 5 to mailbox4
- * CPUA releases host lock
- * CPUB acquires host lock
- * CPUB posts write of index 6 to mailbox4
- * On PCI bus, order reverses and write of 6 posts, then index 5,
- * causing chip to issue full queue of stale commands
- * The mmiowb() prevents future writes from crossing the barrier.
- * See Documentation/driver-api/device-io.rst for more information.
*/
WRT_REG_WORD(&reg->mailbox4, ha->req_ring_index);

--
2.11.0