[SCSI] qla2xxx: Honour "Extended BB credits" bit for CNAs.

We now enable/disable "Additional Receive Credits" in f/w based on nvram
parameter "Extended_BB_Credits" bit (i.e. Enhanced-Features: at offset 0x196).
This is applicable only for GEN2 CNAs.

Signed-off-by: Santosh Vernekar <santosh.vernekar@qlogic.com>
Signed-off-by: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 7 insertions, 1 deletions

diff --git a/drivers/scsi/qla2xxx/qla_mbx.c b/drivers/scsi/qla2xxx/qla_mbx.c
index 6e53bdbb1da8..3ba9a2b56556 100644
--- a/drivers/scsi/qla2xxx/qla_mbx.c
+++ b/drivers/scsi/qla2xxx/qla_mbx.c
@@ -339,6 +339,7 @@ qla2x00_load_ram(scsi_qla_host_t *vha, dma_addr_t req_dma, uint32_t risc_addr,
         return rval;
 }
 
+#define EXTENDED_BB_CREDITS     BIT_0
 /*
  * qla2x00_execute_fw
  *     Start adapter firmware.
@@ -371,7 +372,12 @@ qla2x00_execute_fw(scsi_qla_host_t *vha, uint32_t risc_addr)
                 mcp->mb[1] = MSW(risc_addr);
                 mcp->mb[2] = LSW(risc_addr);
                 mcp->mb[3] = 0;
-                mcp->mb[4] = 0;
+                if (IS_QLA81XX(ha)) {
+                        struct nvram_81xx *nv = ha->nvram;
+                        mcp->mb[4] = (nv->enhanced_features &
+                            EXTENDED_BB_CREDITS);
+                } else
+                        mcp->mb[4] = 0;
                 mcp->out_mb |= MBX_4|MBX_3|MBX_2|MBX_1;
                 mcp->in_mb |= MBX_1;
         } else {