scsi: mpt3sas: Reload SBR without rebooting HBA

Add a new IOCTL command MPT3ENABLEDIAGSBRRELOAD. As a part of firmware
update operation, applications use this IOCTL command to set the SBR reload
bit in the Host Diagnostic register. This permits HBA firmware to be
updated without powercycling the system.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202312280909.MZyhxwBL-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202312281141.jDyPezRn-lkp@intel.com/
Signed-off-by: Ranjan Kumar <ranjan.kumar@broadcom.com>
Link: https://lore.kernel.org/r/20231228114810.11923-2-ranjan.kumar@broadcom.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 67 insertions, 32 deletions

diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
index 8761bc58d965..fc8c45e15235 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
@@ -5481,7 +5481,7 @@ mpt3sas_atto_validate_nvram(struct MPT3SAS_ADAPTER *ioc,
  * mpt3sas_atto_get_sas_addr - get the ATTO SAS address from mfg page 1
  *
  * @ioc : per adapter object
- * @*sas_addr : return sas address
+ * @sas_addr : return sas address
  * Return: 0 for success, non-zero for failure.
  */
 static int
@@ -7914,26 +7914,22 @@ mpt3sas_base_validate_event_type(struct MPT3SAS_ADAPTER *ioc, u32 *event_type)
 }
 
 /**
- * _base_diag_reset - the "big hammer" start of day reset
- * @ioc: per adapter object
- *
- * Return: 0 for success, non-zero for failure.
- */
-static int
-_base_diag_reset(struct MPT3SAS_ADAPTER *ioc)
-{
-	u32 host_diagnostic;
-	u32 ioc_state;
-	u32 count;
-	u32 hcb_size;
-
-	ioc_info(ioc, "sending diag reset !!\n");
-
-	pci_cfg_access_lock(ioc->pdev);
+* mpt3sas_base_unlock_and_get_host_diagnostic- enable Host Diagnostic Register writes
+* @ioc: per adapter object
+* @host_diagnostic: host diagnostic register content
+*
+* Return: 0 for success, non-zero for failure.
+*/
 
-	drsprintk(ioc, ioc_info(ioc, "clear interrupts\n"));
+int
+mpt3sas_base_unlock_and_get_host_diagnostic(struct MPT3SAS_ADAPTER *ioc,
+	u32 *host_diagnostic)
+{
 
+	u32 count;
+	*host_diagnostic = 0;
 	count = 0;
+
 	do {
 		/* Write magic sequence to WriteSequence register
 		 * Loop until in diagnostic mode
@@ -7952,30 +7948,67 @@ _base_diag_reset(struct MPT3SAS_ADAPTER *ioc)
 
 		if (count++ > 20) {
 			ioc_info(ioc,
-			    "Stop writing magic sequence after 20 retries\n");
+				    "Stop writing magic sequence after 20 retries\n");
 			_base_dump_reg_set(ioc);
-			goto out;
+			return -EFAULT;
 		}
 
-		host_diagnostic = ioc->base_readl_ext_retry(&ioc->chip->HostDiagnostic);
+		*host_diagnostic = ioc->base_readl_ext_retry(&ioc->chip->HostDiagnostic);
 		drsprintk(ioc,
-			  ioc_info(ioc, "wrote magic sequence: count(%d), host_diagnostic(0x%08x)\n",
-				   count, host_diagnostic));
+			     ioc_info(ioc, "wrote magic sequence: count(%d), host_diagnostic(0x%08x)\n",
+				     count, *host_diagnostic));
 
-	} while ((host_diagnostic & MPI2_DIAG_DIAG_WRITE_ENABLE) == 0);
+	} while ((*host_diagnostic & MPI2_DIAG_DIAG_WRITE_ENABLE) == 0);
+	return 0;
+}
 
-	hcb_size = ioc->base_readl(&ioc->chip->HCBSize);
+/**
+ * mpt3sas_base_lock_host_diagnostic: Disable Host Diagnostic Register writes
+ * @ioc: per adapter object
+ */
 
+void
+mpt3sas_base_lock_host_diagnostic(struct MPT3SAS_ADAPTER *ioc)
+{
+	drsprintk(ioc, ioc_info(ioc, "disable writes to the diagnostic register\n"));
+	writel(MPI2_WRSEQ_FLUSH_KEY_VALUE, &ioc->chip->WriteSequence);
+}
+
+/**
+ * _base_diag_reset - the "big hammer" start of day reset
+ * @ioc: per adapter object
+ *
+ * Return: 0 for success, non-zero for failure.
+ */
+static int
+_base_diag_reset(struct MPT3SAS_ADAPTER *ioc)
+{
+	u32 host_diagnostic;
+	u32 ioc_state;
+	u32 count;
+	u32 hcb_size;
+
+	ioc_info(ioc, "sending diag reset !!\n");
+
+	pci_cfg_access_lock(ioc->pdev);
+
+	drsprintk(ioc, ioc_info(ioc, "clear interrupts\n"));
+
+	mutex_lock(&ioc->hostdiag_unlock_mutex);
+	if (mpt3sas_base_unlock_and_get_host_diagnostic(ioc, &host_diagnostic))
+		goto out;
+
+	hcb_size = ioc->base_readl(&ioc->chip->HCBSize);
 	drsprintk(ioc, ioc_info(ioc, "diag reset: issued\n"));
 	writel(host_diagnostic | MPI2_DIAG_RESET_ADAPTER,
 	     &ioc->chip->HostDiagnostic);
 
-	/*This delay allows the chip PCIe hardware time to finish reset tasks*/
+	/* This delay allows the chip PCIe hardware time to finish reset tasks */
 	msleep(MPI2_HARD_RESET_PCIE_FIRST_READ_DELAY_MICRO_SEC/1000);
 
 	/* Approximately 300 second max wait */
 	for (count = 0; count < (300000000 /
-		MPI2_HARD_RESET_PCIE_SECOND_READ_DELAY_MICRO_SEC); count++) {
+	    MPI2_HARD_RESET_PCIE_SECOND_READ_DELAY_MICRO_SEC); count++) {
 
 		host_diagnostic = ioc->base_readl_ext_retry(&ioc->chip->HostDiagnostic);
 
@@ -7988,13 +8021,15 @@ _base_diag_reset(struct MPT3SAS_ADAPTER *ioc)
 		if (!(host_diagnostic & MPI2_DIAG_RESET_ADAPTER))
 			break;
 
-		msleep(MPI2_HARD_RESET_PCIE_SECOND_READ_DELAY_MICRO_SEC / 1000);
+		/* Wait to pass the second read delay window */
+		msleep(MPI2_HARD_RESET_PCIE_SECOND_READ_DELAY_MICRO_SEC/1000);
 	}
 
 	if (host_diagnostic & MPI2_DIAG_HCB_MODE) {
 
 		drsprintk(ioc,
-			  ioc_info(ioc, "restart the adapter assuming the HCB Address points to good F/W\n"));
+			ioc_info(ioc, "restart the adapter assuming the\n"
+					"HCB Address points to good F/W\n"));
 		host_diagnostic &= ~MPI2_DIAG_BOOT_DEVICE_SELECT_MASK;
 		host_diagnostic |= MPI2_DIAG_BOOT_DEVICE_SELECT_HCDW;
 		writel(host_diagnostic, &ioc->chip->HostDiagnostic);
@@ -8008,9 +8043,8 @@ _base_diag_reset(struct MPT3SAS_ADAPTER *ioc)
 	writel(host_diagnostic & ~MPI2_DIAG_HOLD_IOC_RESET,
 	    &ioc->chip->HostDiagnostic);
 
-	drsprintk(ioc,
-		  ioc_info(ioc, "disable writes to the diagnostic register\n"));
-	writel(MPI2_WRSEQ_FLUSH_KEY_VALUE, &ioc->chip->WriteSequence);
+	mpt3sas_base_lock_host_diagnostic(ioc);
+	mutex_unlock(&ioc->hostdiag_unlock_mutex);
 
 	drsprintk(ioc, ioc_info(ioc, "Wait for FW to go to the READY state\n"));
 	ioc_state = _base_wait_on_iocstate(ioc, MPI2_IOC_STATE_READY, 20);
@@ -8028,6 +8062,7 @@ _base_diag_reset(struct MPT3SAS_ADAPTER *ioc)
  out:
 	pci_cfg_access_unlock(ioc->pdev);
 	ioc_err(ioc, "diag reset: FAILED\n");
+	mutex_unlock(&ioc->hostdiag_unlock_mutex);
 	return -EFAULT;
 }