scsi: mpt3sas: Dump system registers for debugging

When controller fails to transition to READY state during driver probe,
dump the system interface register set. This will give snapshot of the
firmware status for debugging driver load issues.

Link: https://lore.kernel.org/r/1596096229-3341-3-git-send-email-suganath-prabu.subramani@broadcom.com
Signed-off-by: Suganath Prabu S <suganath-prabu.subramani@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
index 1d64524..712f7f1 100644 (file)
--- a/drivers/scsi/mpt3sas/mpt3sas_base.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
@@ -5618,6 +5618,23 @@ _base_wait_on_iocstate(struct MPT3SAS_ADAPTER *ioc, u32 ioc_state, int timeout)
        return current_state;
 }
 
+/**
+ * _base_dump_reg_set -        This function will print hexdump of register set.
+ * @ioc: per adapter object
+ *
+ * Returns nothing.
+ */
+static inline void
+_base_dump_reg_set(struct MPT3SAS_ADAPTER *ioc)
+{
+       unsigned int i, sz = 256;
+       u32 __iomem *reg = (u32 __iomem *)ioc->chip;
+
+       ioc_info(ioc, "System Register set:\n");
+       for (i = 0; i < (sz / sizeof(u32)); i++)
+               pr_info("%08x: %08x\n", (i * 4), readl(&reg[i]));
+}
+
 /**
  * _base_wait_for_doorbell_int - waiting for controller interrupt(generated by
  * a write to the doorbell)
@@ -6797,6 +6814,7 @@ _base_diag_reset(struct MPT3SAS_ADAPTER *ioc)
                if (count++ > 20) {
                        ioc_info(ioc,
                            "Stop writing magic sequence after 20 retries\n");
+                       _base_dump_reg_set(ioc);
                        goto out;
                }
 
@@ -6825,6 +6843,7 @@ _base_diag_reset(struct MPT3SAS_ADAPTER *ioc)
                if (host_diagnostic == 0xFFFFFFFF) {
                        ioc_info(ioc,
                            "Invalid host diagnostic register value\n");
+                       _base_dump_reg_set(ioc);
                        goto out;
                }
                if (!(host_diagnostic & MPI2_DIAG_RESET_ADAPTER))
@@ -6859,6 +6878,7 @@ _base_diag_reset(struct MPT3SAS_ADAPTER *ioc)
        if (ioc_state) {
                ioc_err(ioc, "%s: failed going to ready state (ioc_state=0x%x)\n",
                        __func__, ioc_state);
+               _base_dump_reg_set(ioc);
                goto out;
        }