[PATCH 2/7] mpt3sas: Dump system registers for debugging.

[Suganath Prabu S <suganath-prabu.subramani@xxxxxxxxxxxx>]

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.

Signed-off-by: Suganath Prabu S <suganath-prabu.subramani@xxxxxxxxxxxx>
---
 drivers/scsi/mpt3sas/mpt3sas_base.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
index 96b78fd..b9d8f08 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
@@ -5617,6 +5617,23 @@ _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)
@@ -6795,6 +6812,7 @@ _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;
 		}
 
@@ -6823,6 +6841,7 @@ _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))
@@ -6857,6 +6876,7 @@ _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;
 	}
 
-- 
2.26.2