scsi: lpfc: Restrict support for 32 byte CDBs to specific HBAs

An older generation of HBAs are failing FCP discovery due to usage of an
outdated field in FCP command WQEs.

Fix by checking the SLI Interface Type register for applicable support of
32 Byte CDB commands, and restore a setting for a WQE path using normal 16
byte CDBs.

Fixes: af20bb7 ("scsi: lpfc: Add support for 32 byte CDBs")
Cc: [email protected] # v6.10+
Signed-off-by: Justin Tee <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Martin K. Petersen <[email protected]>

Author: Justin Tee

drivers/scsi/lpfc/lpfc_hw4.h

@@ -4847,6 +4847,7 @@ struct fcp_iwrite64_wqe {
 #define	cmd_buff_len_SHIFT  16
 #define	cmd_buff_len_MASK  0x00000ffff
 #define	cmd_buff_len_WORD  word3
+/* Note: payload_offset_len field depends on ASIC support */
 #define payload_offset_len_SHIFT 0
 #define payload_offset_len_MASK 0x0000ffff
 #define payload_offset_len_WORD word3
@@ -4863,6 +4864,7 @@ struct fcp_iread64_wqe {
 #define	cmd_buff_len_SHIFT  16
 #define	cmd_buff_len_MASK  0x00000ffff
 #define	cmd_buff_len_WORD  word3
+/* Note: payload_offset_len field depends on ASIC support */
 #define payload_offset_len_SHIFT 0
 #define payload_offset_len_MASK 0x0000ffff
 #define payload_offset_len_WORD word3
@@ -4879,6 +4881,7 @@ struct fcp_icmnd64_wqe {
 #define	cmd_buff_len_SHIFT  16
 #define	cmd_buff_len_MASK  0x00000ffff
 #define	cmd_buff_len_WORD  word3
+/* Note: payload_offset_len field depends on ASIC support */
 #define payload_offset_len_SHIFT 0
 #define payload_offset_len_MASK 0x0000ffff
 #define payload_offset_len_WORD word3

drivers/scsi/lpfc/lpfc_init.c

@@ -4699,6 +4699,7 @@ lpfc_create_port(struct lpfc_hba *phba, int instance, struct device *dev)
 	uint64_t wwn;
 	bool use_no_reset_hba = false;
 	int rc;
+	u8 if_type;
 
 	if (lpfc_no_hba_reset_cnt) {
 		if (phba->sli_rev < LPFC_SLI_REV4 &&
@@ -4773,10 +4774,24 @@ lpfc_create_port(struct lpfc_hba *phba, int instance, struct device *dev)
 	shost->max_id = LPFC_MAX_TARGET;
 	shost->max_lun = vport->cfg_max_luns;
 	shost->this_id = -1;
-	if (phba->sli_rev == LPFC_SLI_REV4)
-		shost->max_cmd_len = LPFC_FCP_CDB_LEN_32;
-	else
+
+	/* Set max_cmd_len applicable to ASIC support */
+	if (phba->sli_rev == LPFC_SLI_REV4) {
+		if_type = bf_get(lpfc_sli_intf_if_type,
+				 &phba->sli4_hba.sli_intf);
+		switch (if_type) {
+		case LPFC_SLI_INTF_IF_TYPE_2:
+			fallthrough;
+		case LPFC_SLI_INTF_IF_TYPE_6:
+			shost->max_cmd_len = LPFC_FCP_CDB_LEN_32;
+			break;
+		default:
+			shost->max_cmd_len = LPFC_FCP_CDB_LEN;
+			break;
+		}
+	} else {
 		shost->max_cmd_len = LPFC_FCP_CDB_LEN;
+	}
 
 	if (phba->sli_rev == LPFC_SLI_REV4) {
 		if (!phba->cfg_fcp_mq_threshold ||

drivers/scsi/lpfc/lpfc_scsi.c

@@ -4760,7 +4760,7 @@ static int lpfc_scsi_prep_cmnd_buf_s4(struct lpfc_vport *vport,
 
 	 /* Word 3 */
 	bf_set(payload_offset_len, &wqe->fcp_icmd,
-	       sizeof(struct fcp_cmnd32) + sizeof(struct fcp_rsp));
+	       sizeof(struct fcp_cmnd) + sizeof(struct fcp_rsp));
 
 	/* Word 6 */
 	bf_set(wqe_ctxt_tag, &wqe->generic.wqe_com,