diff options
| author | John Garry <john.garry@huawei.com> | 2016-09-06 15:36:12 (GMT) |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2016-09-14 16:54:17 (GMT) |
| commit | 4fde02ad66dc9ceb0b55daca21ef33b43df30ded (patch) | |
| tree | 4c707c92f64c6c18bfaa4dd62c6e24f70fc0abbd /drivers/scsi/hisi_sas/hisi_sas_v1_hw.c | |
| parent | e6c346f303d41b8799ea224d0faf1b2caa1c98db (diff) | |
| download | linux-4fde02ad66dc9ceb0b55daca21ef33b43df30ded.tar.xz | |
scsi: hisi_sas: save delivery queue write pointer
Optimise by saving an avoidable read in the get_free_slot function. The
delivery queue write pointer will only be updated by software, so don't
bother re-reading what was already written in the previous call to
start_delivery function.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/hisi_sas/hisi_sas_v1_hw.c')
| -rw-r--r-- | drivers/scsi/hisi_sas/hisi_sas_v1_hw.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c index 3b31b20..b537464 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c +++ b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c @@ -875,12 +875,13 @@ static int get_wideport_bitmap_v1_hw(struct hisi_hba *hisi_hba, int port_id) static int get_free_slot_v1_hw(struct hisi_hba *hisi_hba, int *q, int *s) { struct device *dev = &hisi_hba->pdev->dev; + struct hisi_sas_dq *dq; u32 r, w; int queue = hisi_hba->queue; while (1) { - w = hisi_sas_read32_relaxed(hisi_hba, - DLVRY_Q_0_WR_PTR + (queue * 0x14)); + dq = &hisi_hba->dq[queue]; + w = dq->wr_point; r = hisi_sas_read32_relaxed(hisi_hba, DLVRY_Q_0_RD_PTR + (queue * 0x14)); if (r == (w+1) % HISI_SAS_QUEUE_SLOTS) { @@ -903,10 +904,11 @@ static void start_delivery_v1_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; + struct hisi_sas_dq *dq = &hisi_hba->dq[dlvry_queue]; - hisi_sas_write32(hisi_hba, - DLVRY_Q_0_WR_PTR + (dlvry_queue * 0x14), - ++dlvry_queue_slot % HISI_SAS_QUEUE_SLOTS); + dq->wr_point = ++dlvry_queue_slot % HISI_SAS_QUEUE_SLOTS; + hisi_sas_write32(hisi_hba, DLVRY_Q_0_WR_PTR + (dlvry_queue * 0x14), + dq->wr_point); } static int prep_prd_sge_v1_hw(struct hisi_hba *hisi_hba, |