scsi: qla2xxx: Fix reset of MPI firmware

Normally, the MPI firmware is reset when an MPI dump is collected.  If an
unsaved MPI dump exists in the driver, though, an alternate mechanism is
used. This mechanism, which was not fully correct, is not recommended and
instead an MPI dump template walk is suggested to perform the MPI reset.

To allow for the MPI dump template walk, extra space is reserved in the MPI
dump buffer which gets used only when there is already an MPI dump in
place.

Link: https://lore.kernel.org/r/20200929102152.32278-5-njavali@marvell.com
Fixes: cbb01c2f2f63 ("scsi: qla2xxx: Fix MPI failure AEN (8200) handling")
Cc: stable@vger.kernel.org
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Arun Easi <aeasi@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 13 insertions, 36 deletions

diff --git a/drivers/scsi/qla2xxx/qla_tmpl.c b/drivers/scsi/qla2xxx/qla_tmpl.c
index 591df89a4d13..0af3e7fa31f0 100644
--- a/drivers/scsi/qla2xxx/qla_tmpl.c
+++ b/drivers/scsi/qla2xxx/qla_tmpl.c
@@ -12,33 +12,6 @@
 #define IOBASE(vha)	IOBAR(ISPREG(vha))
 #define INVALID_ENTRY ((struct qla27xx_fwdt_entry *)0xffffffffffffffffUL)
 
-/* hardware_lock assumed held. */
-static void
-qla27xx_write_remote_reg(struct scsi_qla_host *vha,
-			 u32 addr, u32 data)
-{
-	struct device_reg_24xx __iomem *reg = &vha->hw->iobase->isp24;
-
-	ql_dbg(ql_dbg_misc, vha, 0xd300,
-	       "%s: addr/data = %xh/%xh\n", __func__, addr, data);
-
-	wrt_reg_dword(&reg->iobase_addr, 0x40);
-	wrt_reg_dword(&reg->iobase_c4, data);
-	wrt_reg_dword(&reg->iobase_window, addr);
-}
-
-void
-qla27xx_reset_mpi(scsi_qla_host_t *vha)
-{
-	ql_dbg(ql_dbg_misc + ql_dbg_verbose, vha, 0xd301,
-	       "Entered %s.\n", __func__);
-
-	qla27xx_write_remote_reg(vha, 0x104050, 0x40004);
-	qla27xx_write_remote_reg(vha, 0x10405c, 0x4);
-
-	vha->hw->stat.num_mpi_reset++;
-}
-
 static inline void
 qla27xx_insert16(uint16_t value, void *buf, ulong *len)
 {
@@ -1028,7 +1001,6 @@ void
 qla27xx_mpi_fwdump(scsi_qla_host_t *vha, int hardware_locked)
 {
 	ulong flags = 0;
-	bool need_mpi_reset = true;
 
 #ifndef __CHECKER__
 	if (!hardware_locked)
@@ -1036,14 +1008,20 @@ qla27xx_mpi_fwdump(scsi_qla_host_t *vha, int hardware_locked)
 #endif
 	if (!vha->hw->mpi_fw_dump) {
 		ql_log(ql_log_warn, vha, 0x02f3, "-> mpi_fwdump no buffer\n");
-	} else if (vha->hw->mpi_fw_dumped) {
-		ql_log(ql_log_warn, vha, 0x02f4,
-		       "-> MPI firmware already dumped (%p) -- ignoring request\n",
-		       vha->hw->mpi_fw_dump);
 	} else {
 		struct fwdt *fwdt = &vha->hw->fwdt[1];
 		ulong len;
 		void *buf = vha->hw->mpi_fw_dump;
+		bool walk_template_only = false;
+
+		if (vha->hw->mpi_fw_dumped) {
+			/* Use the spare area for any further dumps. */
+			buf += fwdt->dump_size;
+			walk_template_only = true;
+			ql_log(ql_log_warn, vha, 0x02f4,
+			       "-> MPI firmware already dumped -- dump saving to temporary buffer %p.\n",
+			       buf);
+		}
 
 		ql_log(ql_log_warn, vha, 0x02f5, "-> fwdt1 running...\n");
 		if (!fwdt->template) {
@@ -1058,9 +1036,10 @@ qla27xx_mpi_fwdump(scsi_qla_host_t *vha, int hardware_locked)
 			ql_log(ql_log_warn, vha, 0x02f7,
 			       "-> fwdt1 fwdump residual=%+ld\n",
 			       fwdt->dump_size - len);
-		} else {
-			need_mpi_reset = false;
 		}
+		vha->hw->stat.num_mpi_reset++;
+		if (walk_template_only)
+			goto bailout;
 
 		vha->hw->mpi_fw_dump_len = len;
 		vha->hw->mpi_fw_dumped = 1;
@@ -1072,8 +1051,6 @@ qla27xx_mpi_fwdump(scsi_qla_host_t *vha, int hardware_locked)
 	}
 
 bailout:
-	if (need_mpi_reset)
-		qla27xx_reset_mpi(vha);
 #ifndef __CHECKER__
 	if (!hardware_locked)
 		spin_unlock_irqrestore(&vha->hw->hardware_lock, flags);