[PATCH 17/23] hisi_sas: add v2 path to send ssp frame

From: John Garry
Date: Fri Jan 08 2016 - 09:09:07 EST


Include code to prep ssp frame and deliver
to hardware.

Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
---
drivers/scsi/hisi_sas/hisi_sas_v2_hw.c | 185 +++++++++++++++++++++++++++++++++
1 file changed, 185 insertions(+)

diff --git a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
index 0beb6a9..e9d3db9 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
@@ -264,6 +264,11 @@ enum {

#define HISI_SAS_COMMAND_ENTRIES_V2_HW 4096

+#define DIR_NO_DATA 0
+#define DIR_TO_INI 1
+#define DIR_TO_DEVICE 2
+#define DIR_RESERVED 3
+
static u32 hisi_sas_read32(struct hisi_hba *hisi_hba, u32 off)
{
void __iomem *regs = hisi_hba->regs + off;
@@ -271,6 +276,13 @@ static u32 hisi_sas_read32(struct hisi_hba *hisi_hba, u32 off)
return readl(regs);
}

+static u32 hisi_sas_read32_relaxed(struct hisi_hba *hisi_hba, u32 off)
+{
+ void __iomem *regs = hisi_hba->regs + off;
+
+ return readl_relaxed(regs);
+}
+
static void hisi_sas_write32(struct hisi_hba *hisi_hba, u32 off, u32 val)
{
void __iomem *regs = hisi_hba->regs + off;
@@ -651,6 +663,176 @@ static int get_wideport_bitmap_v2_hw(struct hisi_hba *hisi_hba, int port_id)
return bitmap;
}

+/**
+ * This function allocates across all queues to load balance.
+ * Slots are allocated from queues in a round-robin fashion.
+ *
+ * The callpath to this function and upto writing the write
+ * queue pointer should be safe from interruption.
+ */
+static int get_free_slot_v2_hw(struct hisi_hba *hisi_hba, int *q, int *s)
+{
+ struct device *dev = &hisi_hba->pdev->dev;
+ u32 r, w;
+ int queue = hisi_hba->queue;
+
+ while (1) {
+ w = hisi_sas_read32_relaxed(hisi_hba,
+ DLVRY_Q_0_WR_PTR + (queue * 0x14));
+ r = hisi_sas_read32_relaxed(hisi_hba,
+ DLVRY_Q_0_RD_PTR + (queue * 0x14));
+ if (r == (w+1) % HISI_SAS_QUEUE_SLOTS) {
+ queue = (queue + 1) % hisi_hba->queue_count;
+ if (queue == hisi_hba->queue) {
+ dev_warn(dev, "could not find free slot\n");
+ return -EAGAIN;
+ }
+ continue;
+ }
+ break;
+ }
+ hisi_hba->queue = (queue + 1) % hisi_hba->queue_count;
+ *q = queue;
+ *s = w;
+ return 0;
+}
+
+static void start_delivery_v2_hw(struct hisi_hba *hisi_hba)
+{
+ int dlvry_queue = hisi_hba->slot_prep->dlvry_queue;
+ int dlvry_queue_slot = hisi_hba->slot_prep->dlvry_queue_slot;
+
+ hisi_sas_write32(hisi_hba, DLVRY_Q_0_WR_PTR + (dlvry_queue * 0x14),
+ ++dlvry_queue_slot % HISI_SAS_QUEUE_SLOTS);
+}
+
+static int prep_prd_sge_v2_hw(struct hisi_hba *hisi_hba,
+ struct hisi_sas_slot *slot,
+ struct hisi_sas_cmd_hdr *hdr,
+ struct scatterlist *scatter,
+ int n_elem)
+{
+ struct device *dev = &hisi_hba->pdev->dev;
+ struct scatterlist *sg;
+ int i;
+
+ if (n_elem > HISI_SAS_SGE_PAGE_CNT) {
+ dev_err(dev, "prd err: n_elem(%d) > HISI_SAS_SGE_PAGE_CNT",
+ n_elem);
+ return -EINVAL;
+ }
+
+ slot->sge_page = dma_pool_alloc(hisi_hba->sge_page_pool, GFP_ATOMIC,
+ &slot->sge_page_dma);
+ if (!slot->sge_page)
+ return -ENOMEM;
+
+ for_each_sg(scatter, sg, n_elem, i) {
+ struct hisi_sas_sge *entry = &slot->sge_page->sge[i];
+
+ entry->addr = cpu_to_le64(sg_dma_address(sg));
+ entry->page_ctrl_0 = entry->page_ctrl_1 = 0;
+ entry->data_len = cpu_to_le32(sg_dma_len(sg));
+ entry->data_off = 0;
+ }
+
+ hdr->prd_table_addr = cpu_to_le64(slot->sge_page_dma);
+
+ hdr->sg_len = cpu_to_le32(n_elem << CMD_HDR_DATA_SGL_LEN_OFF);
+
+ return 0;
+}
+
+static int prep_ssp_v2_hw(struct hisi_hba *hisi_hba,
+ struct hisi_sas_slot *slot, int is_tmf,
+ struct hisi_sas_tmf_task *tmf)
+{
+ struct sas_task *task = slot->task;
+ struct hisi_sas_cmd_hdr *hdr = slot->cmd_hdr;
+ struct domain_device *device = task->dev;
+ struct hisi_sas_device *sas_dev = device->lldd_dev;
+ struct hisi_sas_port *port = slot->port;
+ struct sas_ssp_task *ssp_task = &task->ssp_task;
+ struct scsi_cmnd *scsi_cmnd = ssp_task->cmd;
+ int has_data = 0, rc, priority = is_tmf;
+ u8 *buf_cmd;
+ u32 dw1 = 0, dw2 = 0;
+
+ hdr->dw0 = cpu_to_le32((1 << CMD_HDR_RESP_REPORT_OFF) |
+ (2 << CMD_HDR_TLR_CTRL_OFF) |
+ (port->id << CMD_HDR_PORT_OFF) |
+ (priority << CMD_HDR_PRIORITY_OFF) |
+ (1 << CMD_HDR_CMD_OFF)); /* ssp */
+
+ dw1 = 1 << CMD_HDR_VDTL_OFF;
+ if (is_tmf) {
+ dw1 |= 2 << CMD_HDR_FRAME_TYPE_OFF;
+ dw1 |= DIR_NO_DATA << CMD_HDR_DIR_OFF;
+ } else {
+ dw1 |= 1 << CMD_HDR_FRAME_TYPE_OFF;
+ switch (scsi_cmnd->sc_data_direction) {
+ case DMA_TO_DEVICE:
+ has_data = 1;
+ dw1 |= DIR_TO_DEVICE << CMD_HDR_DIR_OFF;
+ break;
+ case DMA_FROM_DEVICE:
+ has_data = 1;
+ dw1 |= DIR_TO_INI << CMD_HDR_DIR_OFF;
+ break;
+ default:
+ dw1 &= ~CMD_HDR_DIR_MSK;
+ }
+ }
+
+ /* map itct entry */
+ dw1 |= sas_dev->device_id << CMD_HDR_DEV_ID_OFF;
+ hdr->dw1 = cpu_to_le32(dw1);
+
+ dw2 = (((sizeof(struct ssp_command_iu) + sizeof(struct ssp_frame_hdr)
+ + 3) / 4) << CMD_HDR_CFL_OFF) |
+ ((HISI_SAS_MAX_SSP_RESP_SZ / 4) << CMD_HDR_MRFL_OFF) |
+ (2 << CMD_HDR_SG_MOD_OFF);
+ hdr->dw2 = cpu_to_le32(dw2);
+
+ hdr->transfer_tags = cpu_to_le32(slot->idx);
+
+ if (has_data) {
+ rc = prep_prd_sge_v2_hw(hisi_hba, slot, hdr, task->scatter,
+ slot->n_elem);
+ if (rc)
+ return rc;
+ }
+
+ hdr->data_transfer_len = cpu_to_le32(task->total_xfer_len);
+ hdr->cmd_table_addr = cpu_to_le64(slot->command_table_dma);
+ hdr->sts_buffer_addr = cpu_to_le64(slot->status_buffer_dma);
+
+ buf_cmd = slot->command_table + sizeof(struct ssp_frame_hdr);
+
+ memcpy(buf_cmd, &task->ssp_task.LUN, 8);
+ if (!is_tmf) {
+ buf_cmd[9] = task->ssp_task.task_attr |
+ (task->ssp_task.task_prio << 3);
+ memcpy(buf_cmd + 12, task->ssp_task.cmd->cmnd,
+ task->ssp_task.cmd->cmd_len);
+ } else {
+ buf_cmd[10] = tmf->tmf;
+ switch (tmf->tmf) {
+ case TMF_ABORT_TASK:
+ case TMF_QUERY_TASK:
+ buf_cmd[12] =
+ (tmf->tag_of_task_to_be_managed >> 8) & 0xff;
+ buf_cmd[13] =
+ tmf->tag_of_task_to_be_managed & 0xff;
+ break;
+ default:
+ break;
+ }
+ }
+
+ return 0;
+}
+
static int
slot_complete_v2_hw(struct hisi_hba *hisi_hba, struct hisi_sas_slot *slot,
int abort)
@@ -1217,6 +1399,9 @@ static const struct hisi_sas_hw hisi_sas_v2_hw = {
.hw_init = hisi_sas_v2_init,
.sl_notify = sl_notify_v2_hw,
.get_wideport_bitmap = get_wideport_bitmap_v2_hw,
+ .prep_ssp = prep_ssp_v2_hw,
+ .get_free_slot = get_free_slot_v2_hw,
+ .start_delivery = start_delivery_v2_hw,
.slot_complete = slot_complete_v2_hw,
.max_command_entries = HISI_SAS_COMMAND_ENTRIES_V2_HW,
.complete_hdr_size = sizeof(struct hisi_sas_complete_v2_hdr),
--
1.9.1