common/sfc_efx/base: support getting virtq doorbell offset

Add an API to query the virtqueue doorbell offset in the BAR for a VI.
For vDPA, the virtio net driver notifies the device directly by writing
doorbell. This API would be invoked from vDPA client driver.

Signed-off-by: Vijay Srivastava <vijays@solarflare.com>
Signed-off-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>

diff --git a/drivers/common/sfc_efx/base/efx.h b/drivers/common/sfc_efx/base/efx.h
index c2c73bd..d4b7d7f 100644 (file)
--- a/drivers/common/sfc_efx/base/efx.h
+++ b/drivers/common/sfc_efx/base/efx.h
@@ -4475,6 +4475,18 @@ extern                   void
 efx_virtio_qdestroy(
        __in            efx_virtio_vq_t *evvp);
 
+/*
+ * Get the offset in the BAR of the doorbells for a VI.
+ * net device : doorbell offset of RX & TX queues
+ * block device : request doorbell offset in the BAR.
+ * For further details refer section of 4 of SF-119689
+ */
+LIBEFX_API
+extern __checkReturn   efx_rc_t
+efx_virtio_get_doorbell_offset(
+       __in            efx_virtio_vq_t *evvp,
+       __out           uint32_t *offsetp);
+
 #endif /* EFSYS_OPT_VIRTIO */
 
 #ifdef __cplusplus

diff --git a/drivers/common/sfc_efx/base/efx_impl.h b/drivers/common/sfc_efx/base/efx_impl.h
index f27d9fa..d6742f4 100644 (file)
--- a/drivers/common/sfc_efx/base/efx_impl.h
+++ b/drivers/common/sfc_efx/base/efx_impl.h
@@ -316,6 +316,8 @@ typedef struct efx_virtio_ops_s {
                                efx_virtio_vq_dyncfg_t *);
        efx_rc_t        (*evo_virtio_qstop)(efx_virtio_vq_t *,
                                efx_virtio_vq_dyncfg_t *);
+       efx_rc_t        (*evo_get_doorbell_offset)(efx_virtio_vq_t *,
+                               uint32_t *);
 } efx_virtio_ops_t;
 #endif /* EFSYS_OPT_VIRTIO */
 

diff --git a/drivers/common/sfc_efx/base/efx_virtio.c b/drivers/common/sfc_efx/base/efx_virtio.c
index 68d157b..7303c00 100644 (file)
--- a/drivers/common/sfc_efx/base/efx_virtio.c
+++ b/drivers/common/sfc_efx/base/efx_virtio.c
@@ -12,6 +12,7 @@
 static const efx_virtio_ops_t  __efx_virtio_rhead_ops = {
        rhead_virtio_qstart,                    /* evo_virtio_qstart */
        rhead_virtio_qstop,                     /* evo_virtio_qstop */
+       rhead_virtio_get_doorbell_offset,       /* evo_get_doorbell_offset */
 };
 #endif /* EFSYS_OPT_RIVERHEAD */
 
@@ -213,4 +214,44 @@ efx_virtio_qdestroy(
        }
 }
 
+       __checkReturn   efx_rc_t
+efx_virtio_get_doorbell_offset(
+       __in            efx_virtio_vq_t *evvp,
+       __out           uint32_t *offsetp)
+{
+       efx_nic_t *enp;
+       const efx_virtio_ops_t *evop;
+       efx_rc_t rc;
+
+       if ((evvp == NULL) || (offsetp == NULL)) {
+               rc = EINVAL;
+               goto fail1;
+       }
+
+       enp = evvp->evv_enp;
+       evop = enp->en_evop;
+
+       EFSYS_ASSERT3U(enp->en_magic, ==, EFX_NIC_MAGIC);
+       EFSYS_ASSERT3U(enp->en_mod_flags, &, EFX_MOD_VIRTIO);
+
+       if (evop == NULL) {
+               rc = ENOTSUP;
+               goto fail2;
+       }
+
+       if ((rc = evop->evo_get_doorbell_offset(evvp, offsetp)) != 0)
+               goto fail3;
+
+       return (0);
+
+fail3:
+       EFSYS_PROBE(fail3);
+fail2:
+       EFSYS_PROBE(fail2);
+fail1:
+       EFSYS_PROBE1(fail1, efx_rc_t, rc);
+
+       return (rc);
+}
+
 #endif /* EFSYS_OPT_VIRTIO */

diff --git a/drivers/common/sfc_efx/base/rhead_impl.h b/drivers/common/sfc_efx/base/rhead_impl.h
index a15ac52..4304f63 100644 (file)
--- a/drivers/common/sfc_efx/base/rhead_impl.h
+++ b/drivers/common/sfc_efx/base/rhead_impl.h
@@ -492,6 +492,12 @@ rhead_virtio_qstop(
        __in                            efx_virtio_vq_t *evvp,
        __out_opt                       efx_virtio_vq_dyncfg_t *evvdp);
 
+LIBEFX_INTERNAL
+extern __checkReturn                   efx_rc_t
+rhead_virtio_get_doorbell_offset(
+       __in                            efx_virtio_vq_t *evvp,
+       __out                           uint32_t *offsetp);
+
 #endif /* EFSYS_OPT_VIRTIO */
 
 #ifdef __cplusplus

diff --git a/drivers/common/sfc_efx/base/rhead_virtio.c b/drivers/common/sfc_efx/base/rhead_virtio.c
index ab83b24..e696713 100644 (file)
--- a/drivers/common/sfc_efx/base/rhead_virtio.c
+++ b/drivers/common/sfc_efx/base/rhead_virtio.c
@@ -187,4 +187,97 @@ fail1:
        return (rc);
 }
 
+       __checkReturn   efx_rc_t
+rhead_virtio_get_doorbell_offset(
+       __in            efx_virtio_vq_t *evvp,
+       __out           uint32_t *offsetp)
+{
+       efx_nic_t *enp = evvp->evv_enp;
+       efx_mcdi_req_t req;
+       uint32_t type;
+       EFX_MCDI_DECLARE_BUF(payload, MC_CMD_VIRTIO_GET_DOORBELL_OFFSET_REQ_LEN,
+               MC_CMD_VIRTIO_GET_NET_DOORBELL_OFFSET_RESP_LEN);
+       efx_rc_t rc;
+
+       req.emr_cmd = MC_CMD_VIRTIO_GET_DOORBELL_OFFSET;
+       req.emr_in_buf = payload;
+       req.emr_in_length = MC_CMD_VIRTIO_GET_DOORBELL_OFFSET_REQ_LEN;
+       req.emr_out_buf = payload;
+       req.emr_out_length = MC_CMD_VIRTIO_GET_NET_DOORBELL_OFFSET_RESP_LEN;
+
+       switch (evvp->evv_type) {
+       case EFX_VIRTIO_VQ_TYPE_NET_RXQ:
+       case EFX_VIRTIO_VQ_TYPE_NET_TXQ:
+               type = MC_CMD_VIRTIO_GET_FEATURES_IN_NET;
+               break;
+       case EFX_VIRTIO_VQ_TYPE_BLOCK:
+               type = MC_CMD_VIRTIO_GET_FEATURES_IN_BLOCK;
+               break;
+       default:
+               rc = EINVAL;
+               goto fail1;
+       }
+
+       MCDI_IN_SET_BYTE(req, VIRTIO_GET_DOORBELL_OFFSET_REQ_DEVICE_ID,
+               type);
+       MCDI_IN_SET_WORD(req, VIRTIO_GET_DOORBELL_OFFSET_REQ_TARGET_VF,
+               evvp->evv_target_vf);
+       MCDI_IN_SET_DWORD(req, VIRTIO_GET_DOORBELL_OFFSET_REQ_INSTANCE,
+               evvp->evv_vi_index);
+
+       efx_mcdi_execute(enp, &req);
+
+       if (req.emr_rc != 0) {
+               rc = req.emr_rc;
+               goto fail2;
+       }
+
+       switch (type) {
+       case MC_CMD_VIRTIO_GET_FEATURES_IN_NET:
+               if (req.emr_out_length_used <
+                   MC_CMD_VIRTIO_GET_NET_DOORBELL_OFFSET_RESP_LEN) {
+                       rc = EMSGSIZE;
+                       goto fail3;
+               }
+
+               if (evvp->evv_type == EFX_VIRTIO_VQ_TYPE_NET_RXQ) {
+                       *offsetp = MCDI_OUT_DWORD(req,
+                           VIRTIO_GET_NET_DOORBELL_OFFSET_RESP_RX_DBL_OFFSET);
+               } else if (evvp->evv_type == EFX_VIRTIO_VQ_TYPE_NET_TXQ) {
+                       *offsetp = MCDI_OUT_DWORD(req,
+                           VIRTIO_GET_NET_DOORBELL_OFFSET_RESP_TX_DBL_OFFSET);
+               }
+               break;
+       case MC_CMD_VIRTIO_GET_FEATURES_IN_BLOCK:
+               if (req.emr_out_length_used <
+                   MC_CMD_VIRTIO_GET_BLOCK_DOORBELL_OFFSET_RESP_LEN) {
+                       rc = EMSGSIZE;
+                       goto fail4;
+               }
+
+               *offsetp = MCDI_OUT_DWORD(req,
+                       VIRTIO_GET_BLOCK_DOORBELL_OFFSET_RESP_DBL_OFFSET);
+               break;
+       default:
+               EFSYS_ASSERT(0);
+               rc = EINVAL;
+               goto fail5;
+       }
+
+       return (0);
+
+fail5:
+       EFSYS_PROBE(fail5);
+fail4:
+       EFSYS_PROBE(fail4);
+fail3:
+       EFSYS_PROBE(fail3);
+fail2:
+       EFSYS_PROBE(fail2);
+fail1:
+       EFSYS_PROBE1(fail1, efx_rc_t, rc);
+
+       return (rc);
+}
+
 #endif /* EFSYS_OPT_RIVERHEAD && EFSYS_OPT_VIRTIO */