scsi: hisi_sas: Make max IPTT count equal for all hw revisions

There is a small optimisation to be had by making the max IPTT the same for
all hw revisions, that being we can drop the check for read and write
pointer being the same in the get free slot function.

Change v1 hw to have max IPTT of 4096 - same as v2 and v3 hw - and
drop hisi_sas_hw.max_command_entries.
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/hisi_sas/hisi_sas.h

@@ -31,7 +31,10 @@
 #define HISI_SAS_MAX_DEVICES HISI_SAS_MAX_ITCT_ENTRIES
 #define HISI_SAS_RESET_BIT	0
 #define HISI_SAS_REJECT_CMD_BIT	1
-#define HISI_SAS_RESERVED_IPTT_CNT  96
+#define HISI_SAS_MAX_COMMANDS (HISI_SAS_QUEUE_SLOTS)
+#define HISI_SAS_RESERVED_IPTT  96
+#define HISI_SAS_UNRESERVED_IPTT \
+	(HISI_SAS_MAX_COMMANDS - HISI_SAS_RESERVED_IPTT)
 
 #define HISI_SAS_STATUS_BUF_SZ (sizeof(struct hisi_sas_status_buffer))
 #define HISI_SAS_COMMAND_TABLE_SZ (sizeof(union hisi_sas_command_table))
@@ -292,7 +295,6 @@ struct hisi_sas_hw {
 					  int delay_ms, int timeout_ms);
 	void (*snapshot_prepare)(struct hisi_hba *hisi_hba);
 	void (*snapshot_restore)(struct hisi_hba *hisi_hba);
-	int max_command_entries;
 	int complete_hdr_size;
 	struct scsi_host_template *sht;
 

drivers/scsi/hisi_sas/hisi_sas_main.c

@@ -180,8 +180,8 @@ static void hisi_sas_slot_index_free(struct hisi_hba *hisi_hba, int slot_idx)
 {
 	unsigned long flags;
 
-	if (hisi_hba->hw->slot_index_alloc || (slot_idx >=
-	    hisi_hba->hw->max_command_entries - HISI_SAS_RESERVED_IPTT_CNT)) {
+	if (hisi_hba->hw->slot_index_alloc ||
+	    slot_idx >= HISI_SAS_UNRESERVED_IPTT) {
 		spin_lock_irqsave(&hisi_hba->lock, flags);
 		hisi_sas_slot_index_clear(hisi_hba, slot_idx);
 		spin_unlock_irqrestore(&hisi_hba->lock, flags);
@@ -211,8 +211,7 @@ static int hisi_sas_slot_index_alloc(struct hisi_hba *hisi_hba,
 	if (index >= hisi_hba->slot_index_count) {
 		index = find_next_zero_bit(bitmap,
 				hisi_hba->slot_index_count,
-				hisi_hba->hw->max_command_entries -
-				HISI_SAS_RESERVED_IPTT_CNT);
+				HISI_SAS_UNRESERVED_IPTT);
 		if (index >= hisi_hba->slot_index_count) {
 			spin_unlock_irqrestore(&hisi_hba->lock, flags);
 			return -SAS_QUEUE_FULL;
@@ -2291,7 +2290,7 @@ static struct sas_domain_function_template hisi_sas_transport_ops = {
 
 void hisi_sas_init_mem(struct hisi_hba *hisi_hba)
 {
-	int i, s, j, max_command_entries = hisi_hba->hw->max_command_entries;
+	int i, s, j, max_command_entries = HISI_SAS_MAX_COMMANDS;
 	struct hisi_sas_breakpoint *sata_breakpoint = hisi_hba->sata_breakpoint;
 
 	for (i = 0; i < hisi_hba->queue_count; i++) {
@@ -2328,7 +2327,7 @@ EXPORT_SYMBOL_GPL(hisi_sas_init_mem);
 int hisi_sas_alloc(struct hisi_hba *hisi_hba)
 {
 	struct device *dev = hisi_hba->dev;
-	int i, j, s, max_command_entries = hisi_hba->hw->max_command_entries;
+	int i, j, s, max_command_entries = HISI_SAS_MAX_COMMANDS;
 	int max_command_entries_ru, sz_slot_buf_ru;
 	int blk_cnt, slots_per_blk;
 
@@ -2458,8 +2457,7 @@ int hisi_sas_alloc(struct hisi_hba *hisi_hba)
 	hisi_sas_init_mem(hisi_hba);
 
 	hisi_sas_slot_index_init(hisi_hba);
-	hisi_hba->last_slot_index = hisi_hba->hw->max_command_entries -
-		HISI_SAS_RESERVED_IPTT_CNT;
+	hisi_hba->last_slot_index = HISI_SAS_UNRESERVED_IPTT;
 
 	hisi_hba->wq = create_singlethread_workqueue(dev_name(dev));
 	if (!hisi_hba->wq) {
@@ -2672,13 +2670,11 @@ int hisi_sas_probe(struct platform_device *pdev,
 	shost->max_channel = 1;
 	shost->max_cmd_len = 16;
 	if (hisi_hba->hw->slot_index_alloc) {
-		shost->can_queue = hisi_hba->hw->max_command_entries;
-		shost->cmd_per_lun = hisi_hba->hw->max_command_entries;
+		shost->can_queue = HISI_SAS_MAX_COMMANDS;
+		shost->cmd_per_lun = HISI_SAS_MAX_COMMANDS;
 	} else {
-		shost->can_queue = hisi_hba->hw->max_command_entries -
-			HISI_SAS_RESERVED_IPTT_CNT;
-		shost->cmd_per_lun = hisi_hba->hw->max_command_entries -
-			HISI_SAS_RESERVED_IPTT_CNT;
+		shost->can_queue = HISI_SAS_UNRESERVED_IPTT;
+		shost->cmd_per_lun = HISI_SAS_UNRESERVED_IPTT;
 	}
 
 	sha->sas_ha_name = DRV_NAME;
@@ -2794,7 +2790,7 @@ static void hisi_sas_debugfs_snapshot_itct_reg(struct hisi_hba *hisi_hba)
 
 static void hisi_sas_debugfs_snapshot_iost_reg(struct hisi_hba *hisi_hba)
 {
-	int max_command_entries = hisi_hba->hw->max_command_entries;
+	int max_command_entries = HISI_SAS_MAX_COMMANDS;
 	void *databuf = hisi_hba->debugfs_iost;
 	struct hisi_sas_iost *iost;
 	int i;
@@ -3008,7 +3004,7 @@ static int hisi_sas_debugfs_iost_show(struct seq_file *s, void *p)
 {
 	struct hisi_hba *hisi_hba = s->private;
 	struct hisi_sas_iost *debugfs_iost = hisi_hba->debugfs_iost;
-	int i, ret, max_command_entries = hisi_hba->hw->max_command_entries;
+	int i, ret, max_command_entries = HISI_SAS_MAX_COMMANDS;
 	__le64 *iost = &debugfs_iost->qw0;
 
 	for (i = 0; i < max_command_entries; i++, debugfs_iost++) {
@@ -3177,7 +3173,7 @@ EXPORT_SYMBOL_GPL(hisi_sas_debugfs_work_handler);
 
 void hisi_sas_debugfs_init(struct hisi_hba *hisi_hba)
 {
-	int max_command_entries = hisi_hba->hw->max_command_entries;
+	int max_command_entries = HISI_SAS_MAX_COMMANDS;
 	struct device *dev = hisi_hba->dev;
 	int p, i, c, d;
 	size_t sz;

drivers/scsi/hisi_sas/hisi_sas_v1_hw.c

@@ -401,8 +401,6 @@ enum {
 	TRANS_RX_SMP_RESP_TIMEOUT_ERR, /* 0x31a */
 };
 
-#define HISI_SAS_COMMAND_ENTRIES_V1_HW 8192
-
 #define HISI_SAS_PHY_MAX_INT_NR (HISI_SAS_PHY_INT_NR * HISI_SAS_MAX_PHYS)
 #define HISI_SAS_CQ_MAX_INT_NR (HISI_SAS_MAX_QUEUES)
 #define HISI_SAS_FATAL_INT_NR (2)
@@ -1830,7 +1828,6 @@ static const struct hisi_sas_hw hisi_sas_v1_hw = {
 	.phy_set_linkrate = phy_set_linkrate_v1_hw,
 	.phy_get_max_linkrate = phy_get_max_linkrate_v1_hw,
 	.get_wideport_bitmap = get_wideport_bitmap_v1_hw,
-	.max_command_entries = HISI_SAS_COMMAND_ENTRIES_V1_HW,
 	.complete_hdr_size = sizeof(struct hisi_sas_complete_v1_hdr),
 	.sht = &sht_v1_hw,
 };

drivers/scsi/hisi_sas/hisi_sas_v2_hw.c

@@ -3616,7 +3616,6 @@ static const struct hisi_sas_hw hisi_sas_v2_hw = {
 	.get_events = phy_get_events_v2_hw,
 	.phy_set_linkrate = phy_set_linkrate_v2_hw,
 	.phy_get_max_linkrate = phy_get_max_linkrate_v2_hw,
-	.max_command_entries = HISI_SAS_COMMAND_ENTRIES_V2_HW,
 	.complete_hdr_size = sizeof(struct hisi_sas_complete_v2_hdr),
 	.soft_reset = soft_reset_v2_hw,
 	.get_phys_state = get_phys_state_v2_hw,

drivers/scsi/hisi_sas/hisi_sas_v3_hw.c

@@ -2935,7 +2935,6 @@ static struct scsi_host_template sht_v3_hw = {
 static const struct hisi_sas_hw hisi_sas_v3_hw = {
 	.hw_init = hisi_sas_v3_init,
 	.setup_itct = setup_itct_v3_hw,
-	.max_command_entries = HISI_SAS_COMMAND_ENTRIES_V3_HW,
 	.get_wideport_bitmap = get_wideport_bitmap_v3_hw,
 	.complete_hdr_size = sizeof(struct hisi_sas_complete_v3_hdr),
 	.clear_itct = clear_itct_v3_hw,
@@ -3076,10 +3075,8 @@ hisi_sas_v3_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	shost->max_lun = ~0;
 	shost->max_channel = 1;
 	shost->max_cmd_len = 16;
-	shost->can_queue = hisi_hba->hw->max_command_entries -
-		HISI_SAS_RESERVED_IPTT_CNT;
-	shost->cmd_per_lun = hisi_hba->hw->max_command_entries -
-		HISI_SAS_RESERVED_IPTT_CNT;
+	shost->can_queue = HISI_SAS_UNRESERVED_IPTT;
+	shost->cmd_per_lun = HISI_SAS_UNRESERVED_IPTT;
 
 	sha->sas_ha_name = DRV_NAME;
 	sha->dev = dev;