[SCSI] megaraid_sas: FW transition and q size changes

This patch has the following enhancements :
        a. handles new transition states of FW to support controller hotplug.
        b. It reduces by 1 the maximum cmds that the driver may send to FW.
        c. Sends "Stop Processing" cmd to FW before returning failure from reset routine
        d. Adds print in megasas_transition routine
        e. Sends "RESET" flag to FW to do a soft reset of controller
to move from Operational to Ready state.
	f. Sending correct pointer (cmd->sense) to pci_pool_free

Signed-off-by: Sumant Patro <Sumant.Patro@lsil.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

2 files changed, 38 insertions, 8 deletions

diff --git a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c
index 4cab5b534b25..38733b6009a4 100644
--- a/drivers/scsi/megaraid/megaraid_sas.c
+++ b/drivers/scsi/megaraid/megaraid_sas.c
@@ -832,6 +832,12 @@ static int megasas_wait_for_outstanding(struct megasas_instance *instance)
         }
 
         if (atomic_read(&instance->fw_outstanding)) {
+                /*
+                * Send signal to FW to stop processing any pending cmds.
+                * The controller will be taken offline by the OS now.
+                */
+                writel(MFI_STOP_ADP,
+                                &instance->reg_set->inbound_doorbell);
                 instance->hw_crit_error = 1;
                 return FAILED;
         }
@@ -1229,10 +1235,12 @@ megasas_transition_to_ready(struct megasas_instance* instance)
 
         fw_state = instance->instancet->read_fw_status_reg(instance->reg_set) & MFI_STATE_MASK;
 
+        if (fw_state != MFI_STATE_READY)
+                printk(KERN_INFO "megasas: Waiting for FW to come to ready"
+                       " state\n");
+
         while (fw_state != MFI_STATE_READY) {
 
-                printk(KERN_INFO "megasas: Waiting for FW to come to ready"
-                       " state\n");
                 switch (fw_state) {
 
                 case MFI_STATE_FAULT:
@@ -1244,19 +1252,27 @@ megasas_transition_to_ready(struct megasas_instance* instance)
                         /*
                          * Set the CLR bit in inbound doorbell
                          */
-                        writel(MFI_INIT_CLEAR_HANDSHAKE,
+                        writel(MFI_INIT_CLEAR_HANDSHAKE|MFI_INIT_HOTPLUG,
                                 &instance->reg_set->inbound_doorbell);
 
                         max_wait = 2;
                         cur_state = MFI_STATE_WAIT_HANDSHAKE;
                         break;
 
+                case MFI_STATE_BOOT_MESSAGE_PENDING:
+                        writel(MFI_INIT_HOTPLUG,
+                                &instance->reg_set->inbound_doorbell);
+
+                        max_wait = 10;
+                        cur_state = MFI_STATE_BOOT_MESSAGE_PENDING;
+                        break;
+
                 case MFI_STATE_OPERATIONAL:
                         /*
-                         * Bring it to READY state; assuming max wait 2 secs
+                         * Bring it to READY state; assuming max wait 10 secs
                          */
                         megasas_disable_intr(instance);
-                        writel(MFI_INIT_READY, &instance->reg_set->inbound_doorbell);
+                        writel(MFI_RESET_FLAGS, &instance->reg_set->inbound_doorbell);
 
                         max_wait = 10;
                         cur_state = MFI_STATE_OPERATIONAL;
@@ -1323,6 +1339,7 @@ megasas_transition_to_ready(struct megasas_instance* instance)
                         return -ENODEV;
                 }
         };
+        printk(KERN_INFO "megasas: FW now in Ready state\n");
 
         return 0;
 }
@@ -1352,7 +1369,7 @@ static void megasas_teardown_frame_pool(struct megasas_instance *instance)
                                       cmd->frame_phys_addr);
 
                 if (cmd->sense)
-                        pci_pool_free(instance->sense_dma_pool, cmd->frame,
+                        pci_pool_free(instance->sense_dma_pool, cmd->sense,
                                       cmd->sense_phys_addr);
         }
 
@@ -1690,6 +1707,12 @@ static int megasas_init_mfi(struct megasas_instance *instance)
          * Get various operational parameters from status register
          */
         instance->max_fw_cmds = instance->instancet->read_fw_status_reg(reg_set) & 0x00FFFF;
+        /*
+         * Reduce the max supported cmds by 1. This is to ensure that the
+         * reply_q_sz (1 more than the max cmd that driver may send)
+         * does not exceed max cmds that the FW can support
+         */
+        instance->max_fw_cmds = instance->max_fw_cmds-1;
         instance->max_num_sge = (instance->instancet->read_fw_status_reg(reg_set) & 0xFF0000) >> 
                                         0x10;
         /*
diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h
index 3531a14222a7..930c06d0a4f7 100644
--- a/drivers/scsi/megaraid/megaraid_sas.h
+++ b/drivers/scsi/megaraid/megaraid_sas.h
@@ -50,6 +50,7 @@
 #define MFI_STATE_WAIT_HANDSHAKE                0x60000000
 #define MFI_STATE_FW_INIT_2                     0x70000000
 #define MFI_STATE_DEVICE_SCAN                   0x80000000
+#define MFI_STATE_BOOT_MESSAGE_PENDING          0x90000000
 #define MFI_STATE_FLUSH_CACHE                   0xA0000000
 #define MFI_STATE_READY                         0xB0000000
 #define MFI_STATE_OPERATIONAL                   0xC0000000
@@ -64,12 +65,18 @@
  * READY        : Move from OPERATIONAL to READY state; discard queue info
  * MFIMODE      : Discard (possible) low MFA posted in 64-bit mode (??)
  * CLR_HANDSHAKE: FW is waiting for HANDSHAKE from BIOS or Driver
+ * HOTPLUG      : Resume from Hotplug
+ * MFI_STOP_ADP : Send signal to FW to stop processing
  */
-#define MFI_INIT_ABORT                          0x00000000
+#define MFI_INIT_ABORT                          0x00000001
 #define MFI_INIT_READY                          0x00000002
 #define MFI_INIT_MFIMODE                        0x00000004
 #define MFI_INIT_CLEAR_HANDSHAKE                0x00000008
-#define MFI_RESET_FLAGS                         MFI_INIT_READY|MFI_INIT_MFIMODE
+#define MFI_INIT_HOTPLUG                        0x00000010
+#define MFI_STOP_ADP                            0x00000020
+#define MFI_RESET_FLAGS                         MFI_INIT_READY| \
+                                                MFI_INIT_MFIMODE| \
+                                                MFI_INIT_ABORT
 
 /**
  * MFI frame flags