[SCSI] lpfc 8.1.4 : Introduce lpfc_reset_barrier() function for resets on dual channel adapters

Introduce lpfc_reset_barrier() function for resets on dual channel adapters

Workaround for a hardware errata on dual channel asics. There is a
potential for the chip to lock up on a reset if a shared dma engine is in
use. The (ugly) work around requires a reset process which uses a mailbox
command to synchronize the independent channels prior to the reset to
avoid the issue. Unfortunately, the timing windows required to ensure this
workaround succeeds are very specific, meaning we can't release the cpu
during the barrier.

Signed-off-by: James Smart <James.Smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/scsi/lpfc/lpfc_crtn.h b/drivers/scsi/lpfc/lpfc_crtn.h
index f716c1d85f41..fad607b2e6f4 100644
--- a/drivers/scsi/lpfc/lpfc_crtn.h
+++ b/drivers/scsi/lpfc/lpfc_crtn.h
@@ -139,6 +139,7 @@ struct lpfc_iocbq * lpfc_sli_get_iocbq(struct lpfc_hba *);
 void lpfc_sli_release_iocbq(struct lpfc_hba * phba, struct lpfc_iocbq * iocb);
 uint16_t lpfc_sli_next_iotag(struct lpfc_hba * phba, struct lpfc_iocbq * iocb);
 
+void lpfc_reset_barrier(struct lpfc_hba * phba);
 int lpfc_sli_brdready(struct lpfc_hba *, uint32_t);
 int lpfc_sli_brdkill(struct lpfc_hba *);
 int lpfc_sli_brdreset(struct lpfc_hba *);