scsi: lpfc: Add push-to-adapter support to sli4

New if_type=6 adapters support an additional BAR that provides
apertures to allow direct WQE to adapter push support - termed
Direct Packet Push (DPP). WQ creation differs slightly to ask for
a WQ to be DPP-ized. When submitting a WQE to a DPP WQ, it is
submitted to the host memory for the WQ normally, but is also
written by the host cpu directly to a BAR aperture.  Write buffer
coalescing in hardware is (hopefully) turned on, enabling single
pci write operation support. The doorbell is thing rung to indicate
the WQE is available and was pushed to the aperture.

This patch:
- Updates the WQ Create commands for the DPP options
- Adds the bar mapping for if_type=6 DPP bar
- Adds the WQE pushing to the DDP aperture received from WQ create
- Adds a new module parameter to disable DPP operation if desired.
  Default is enabled.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/scsi/lpfc/lpfc_attr.c b/drivers/scsi/lpfc/lpfc_attr.c
index 7be4bdef4d42..32f17e19e123 100644
--- a/drivers/scsi/lpfc/lpfc_attr.c
+++ b/drivers/scsi/lpfc/lpfc_attr.c
@@ -5186,6 +5186,14 @@ LPFC_ATTR_R(enable_mds_diags, 0, 0, 1, "Enable MDS Diagnostics");
  */
 LPFC_BBCR_ATTR_RW(enable_bbcr, 1, 0, 1, "Enable BBC Recovery");
 
+/*
+ * lpfc_enable_dpp: Enable DPP on G7
+ *       0  = DPP on G7 disabled
+ *       1  = DPP on G7 enabled (default)
+ * Value range is [0,1]. Default value is 1.
+ */
+LPFC_ATTR_RW(enable_dpp, 1, 0, 1, "Enable Direct Packet Push");
+
 struct device_attribute *lpfc_hba_attrs[] = {
 	&dev_attr_nvme_info,
 	&dev_attr_bg_info,
@@ -5294,6 +5302,7 @@ struct device_attribute *lpfc_hba_attrs[] = {
 	&dev_attr_lpfc_xlane_supported,
 	&dev_attr_lpfc_enable_mds_diags,
 	&dev_attr_lpfc_enable_bbcr,
+	&dev_attr_lpfc_enable_dpp,
 	NULL,
 };
 
@@ -6306,6 +6315,7 @@ lpfc_get_cfgparam(struct lpfc_hba *phba)
 	lpfc_fcp_io_channel_init(phba, lpfc_fcp_io_channel);
 	lpfc_nvme_io_channel_init(phba, lpfc_nvme_io_channel);
 	lpfc_enable_bbcr_init(phba, lpfc_enable_bbcr);
+	lpfc_enable_dpp_init(phba, lpfc_enable_dpp);
 
 	if (phba->sli_rev != LPFC_SLI_REV4) {
 		/* NVME only supported on SLI4 */