[SCSI] hpsa: add ioaccell mode 1 RAID offload support.

This enables sending i/o's destined for RAID logical drives
which can be serviced by a single physical disk down a different,
faster i/o path directly to physical drives for certain logical
volumes on SSDs bypassing the Smart Array RAID stack for a
performance improvement.
Signed-off-by: NMatt Gates <matthew.gates@hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NScott Teel <scott.teel@hp.com>
Signed-off-by: NMike Miller <michael.miller@canonical.com>
Signed-off-by: NDon Brace <brace@beardog.cce.hp.com>
Signed-off-by: NJoe Handzik <joseph.t.handzik@hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

drivers/scsi/hpsa.h

@@ -47,6 +47,13 @@ struct hpsa_scsi_dev_t {
 	unsigned char model[16];        /* bytes 16-31 of inquiry data */
 	unsigned char raid_level;	/* from inquiry page 0xC1 */
 	u32 ioaccel_handle;
+	int offload_config;		/* I/O accel RAID offload configured */
+	int offload_enabled;		/* I/O accel RAID offload enabled */
+	int offload_to_mirror;		/* Send next I/O accelerator RAID
+					 * offload request to mirror drive
+					 */
+	struct raid_map_data raid_map;	/* I/O accelerator RAID map */
+
 };
 
 struct reply_pool {
@@ -133,6 +140,10 @@ struct ctlr_info {
 	u32 *blockFetchTable;
 	u32 *ioaccel1_blockFetchTable;
 	unsigned char *hba_inquiry_data;
+	u32 driver_support;
+	u32 fw_support;
+	int ioaccel_support;
+	int ioaccel_maxsg;
 	u64 last_intr_timestamp;
 	u32 last_heartbeat;
 	u64 last_heartbeat_timestamp;
@@ -406,8 +417,7 @@ static bool SA5_ioaccel_mode1_intr_pending(struct ctlr_info *h)
 #define IOACCEL_MODE1_CONSUMER_INDEX     0x1BC
 #define IOACCEL_MODE1_REPLY_UNUSED       0xFFFFFFFFFFFFFFFFULL
 
-static unsigned long SA5_ioaccel_mode1_completed(struct ctlr_info *h,
-							u8 q)
+static unsigned long SA5_ioaccel_mode1_completed(struct ctlr_info *h, u8 q)
 {
 	u64 register_value;
 	struct reply_pool *rq = &h->reply_queue[q];
@@ -420,12 +430,18 @@ static unsigned long SA5_ioaccel_mode1_completed(struct ctlr_info *h,
 		rq->head[rq->current_entry] = IOACCEL_MODE1_REPLY_UNUSED;
 		if (++rq->current_entry == rq->size)
 			rq->current_entry = 0;
+		/*
+		 * @todo
+		 *
+		 * Don't really need to write the new index after each command,
+		 * but with current driver design this is easiest.
+		 */
+		wmb();
+		writel((q << 24) | rq->current_entry, h->vaddr +
+				IOACCEL_MODE1_CONSUMER_INDEX);
 		spin_lock_irqsave(&h->lock, flags);
 		h->commands_outstanding--;
 		spin_unlock_irqrestore(&h->lock, flags);
-	} else {
-		writel((q << 24) | rq->current_entry,
-			h->vaddr + IOACCEL_MODE1_CONSUMER_INDEX);
 	}
 	return (unsigned long) register_value;
 }

drivers/scsi/hpsa_cmd.h

@@ -42,6 +42,8 @@
 #define CMD_UNSOLICITED_ABORT   0x000A
 #define CMD_TIMEOUT             0x000B
 #define CMD_UNABORTABLE		0x000C
+#define CMD_IOACCEL_DISABLED	0x000E
+
 
 /* Unit Attentions ASC's as defined for the MSA2012sa */
 #define POWER_OR_RESET			0x29
@@ -137,6 +139,11 @@
 #define CFGTBL_BusType_Ultra3   0x00000002l
 #define CFGTBL_BusType_Fibre1G  0x00000100l
 #define CFGTBL_BusType_Fibre2G  0x00000200l
+
+/* VPD Inquiry types */
+#define HPSA_VPD_LV_DEVICE_GEOMETRY     0xC1
+#define HPSA_VPD_LV_IOACCEL_STATUS      0xC2
+
 struct vals32 {
 	u32   lower;
 	u32   upper;
@@ -165,9 +172,46 @@ struct InquiryData {
 #define HPSA_REPORT_LOG 0xc2    /* Report Logical LUNs */
 #define HPSA_REPORT_PHYS 0xc3   /* Report Physical LUNs */
 #define HPSA_REPORT_PHYS_EXTENDED 0x02
+#define HPSA_CISS_READ	0xc0	/* CISS Read */
+#define HPSA_GET_RAID_MAP 0xc8	/* CISS Get RAID Layout Map */
+
+#define RAID_MAP_MAX_ENTRIES   256
+
+struct raid_map_disk_data {
+	u32   ioaccel_handle;         /**< Handle to access this disk via the
+					*  I/O accelerator */
+	u8    xor_mult[2];            /**< XOR multipliers for this position,
+					*  valid for data disks only */
+	u8    reserved[2];
+};
+
+struct raid_map_data {
+	u32   structure_size;		/* Size of entire structure in bytes */
+	u32   volume_blk_size;		/* bytes / block in the volume */
+	u64   volume_blk_cnt;		/* logical blocks on the volume */
+	u8    phys_blk_shift;		/* Shift factor to convert between
+					 * units of logical blocks and physical
+					 * disk blocks */
+	u8    parity_rotation_shift;	/* Shift factor to convert between units
+					 * of logical stripes and physical
+					 * stripes */
+	u16   strip_size;		/* blocks used on each disk / stripe */
+	u64   disk_starting_blk;	/* First disk block used in volume */
+	u64   disk_blk_cnt;		/* disk blocks used by volume / disk */
+	u16   data_disks_per_row;	/* data disk entries / row in the map */
+	u16   metadata_disks_per_row;	/* mirror/parity disk entries / row
+					 * in the map */
+	u16   row_cnt;			/* rows in each layout map */
+	u16   layout_map_count;		/* layout maps (1 map per mirror/parity
+					 * group) */
+	u8    reserved[20];
+	struct raid_map_disk_data data[RAID_MAP_MAX_ENTRIES];
+};
+
 struct ReportLUNdata {
 	u8 LUNListLength[4];
-	u32 reserved;
+	u8 extended_response_flag;
+	u8 reserved[3];
 	u8 LUN[HPSA_MAX_LUN][8];
 };
 
@@ -331,7 +375,7 @@ struct CommandList {
  */
 #define IS_32_BIT ((8 - sizeof(long))/4)
 #define IS_64_BIT (!IS_32_BIT)
-#define PAD_32 (4)
+#define PAD_32 (36)
 #define PAD_64 (4)
 #define COMMANDLIST_PAD (IS_32_BIT * PAD_32 + IS_64_BIT * PAD_64)
 	u8 pad[COMMANDLIST_PAD];
@@ -371,6 +415,11 @@ struct io_accel1_cmd {
 	struct vals32 host_addr;	/* 0x70 - 0x77 */
 	u8  CISS_LUN[8];		/* 0x78 - 0x7F */
 	struct SGDescriptor SG[IOACCEL1_MAXSGENTRIES];
+#define IOACCEL1_PAD_64 0
+#define IOACCEL1_PAD_32 0
+#define IOACCEL1_PAD (IS_32_BIT * IOACCEL1_PAD_32 + \
+			IS_64_BIT * IOACCEL1_PAD_64)
+	u8 pad[IOACCEL1_PAD];
 };
 
 #define IOACCEL1_FUNCTION_SCSIIO        0x00
@@ -407,6 +456,8 @@ struct HostWrite {
 #define MEMQ_MODE       0x08
 #define IOACCEL_MODE_1  0x80
 
+#define DRIVER_SUPPORT_UA_ENABLE        0x00000001
+
 struct CfgTable {
 	u8            Signature[4];
 	u32		SpecValence;
@@ -435,8 +486,16 @@ struct CfgTable {
 	u32		misc_fw_support; /* offset 0x78 */
 #define			MISC_FW_DOORBELL_RESET (0x02)
 #define			MISC_FW_DOORBELL_RESET2 (0x010)
+#define			MISC_FW_RAID_OFFLOAD_BASIC (0x020)
+#define			MISC_FW_EVENT_NOTIFY (0x080)
 	u8		driver_version[32];
-
+	u32             max_cached_write_size;
+	u8              driver_scratchpad[16];
+	u32             max_error_info_length;
+	u32		io_accel_max_embedded_sg_count;
+	u32		io_accel_request_size_offset;
+	u32		event_notify;
+	u32		clear_event_notify;
 };
 
 #define NUM_BLOCKFETCH_ENTRIES 8