[PATCH net-next v3 04/14] sfc: evaluate vdpa support based on FW capability CLIENT_CMD_VF_PROXY

From: Gautam Dawar
Date: Thu Apr 06 2023 - 03:02:15 EST


Add and update vdpa_supported field to struct efx_nic to true if
running Firmware supports CLIENT_CMD_VF_PROXY capability. This is
required to ensure DMA isolation between MCDI command buffer and guest
buffers.
Also, split efx_ef100_init_datapath_caps() into a generic API that vDPA
can use, and the netdev (TSO) specific code is moved to a new function
efx_ef100_update_tso_features()

Signed-off-by: Gautam Dawar <gautam.dawar@xxxxxxx>
---
drivers/net/ethernet/sfc/ef100_netdev.c | 26 +++++++++++++--
drivers/net/ethernet/sfc/ef100_nic.c | 43 +++++++++++++------------
drivers/net/ethernet/sfc/ef100_nic.h | 6 ++--
3 files changed, 49 insertions(+), 26 deletions(-)

diff --git a/drivers/net/ethernet/sfc/ef100_netdev.c b/drivers/net/ethernet/sfc/ef100_netdev.c
index d916877b5a9a..5d93e870d9b7 100644
--- a/drivers/net/ethernet/sfc/ef100_netdev.c
+++ b/drivers/net/ethernet/sfc/ef100_netdev.c
@@ -355,6 +355,28 @@ void ef100_remove_netdev(struct efx_probe_data *probe_data)
efx->state = STATE_PROBED;
}

+static void efx_ef100_update_tso_features(struct efx_nic *efx)
+{
+ struct ef100_nic_data *nic_data = efx->nic_data;
+ struct net_device *net_dev = efx->net_dev;
+ netdev_features_t tso;
+
+ if (!efx_ef100_has_cap(nic_data->datapath_caps2, TX_TSO_V3))
+ return;
+
+ tso = NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_GSO_PARTIAL |
+ NETIF_F_GSO_UDP_TUNNEL | NETIF_F_GSO_UDP_TUNNEL_CSUM |
+ NETIF_F_GSO_GRE | NETIF_F_GSO_GRE_CSUM;
+
+ net_dev->features |= tso;
+ net_dev->hw_features |= tso;
+ net_dev->hw_enc_features |= tso;
+ /* EF100 HW can only offload outer checksums if they are UDP,
+ * so for GRE_CSUM we have to use GSO_PARTIAL.
+ */
+ net_dev->gso_partial_features |= NETIF_F_GSO_GRE_CSUM;
+}
+
int ef100_probe_netdev(struct efx_probe_data *probe_data)
{
struct efx_nic *efx = &probe_data->efx;
@@ -387,9 +409,7 @@ int ef100_probe_netdev(struct efx_probe_data *probe_data)
ESE_EF100_DP_GZ_TSO_MAX_HDR_NUM_SEGS_DEFAULT);
efx->mdio.dev = net_dev;

- rc = efx_ef100_init_datapath_caps(efx);
- if (rc < 0)
- goto fail;
+ efx_ef100_update_tso_features(efx);

rc = ef100_phy_probe(efx);
if (rc)
diff --git a/drivers/net/ethernet/sfc/ef100_nic.c b/drivers/net/ethernet/sfc/ef100_nic.c
index 54b2ee7a5be6..498b398175d7 100644
--- a/drivers/net/ethernet/sfc/ef100_nic.c
+++ b/drivers/net/ethernet/sfc/ef100_nic.c
@@ -162,7 +162,7 @@ int ef100_get_mac_address(struct efx_nic *efx, u8 *mac_address,
return 0;
}

-int efx_ef100_init_datapath_caps(struct efx_nic *efx)
+static int efx_ef100_init_datapath_caps(struct efx_nic *efx)
{
MCDI_DECLARE_BUF(outbuf, MC_CMD_GET_CAPABILITIES_V7_OUT_LEN);
struct ef100_nic_data *nic_data = efx->nic_data;
@@ -198,25 +198,22 @@ int efx_ef100_init_datapath_caps(struct efx_nic *efx)
if (rc)
return rc;

- if (efx_ef100_has_cap(nic_data->datapath_caps2, TX_TSO_V3)) {
- struct net_device *net_dev = efx->net_dev;
- netdev_features_t tso = NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_GSO_PARTIAL |
- NETIF_F_GSO_UDP_TUNNEL | NETIF_F_GSO_UDP_TUNNEL_CSUM |
- NETIF_F_GSO_GRE | NETIF_F_GSO_GRE_CSUM;
-
- net_dev->features |= tso;
- net_dev->hw_features |= tso;
- net_dev->hw_enc_features |= tso;
- /* EF100 HW can only offload outer checksums if they are UDP,
- * so for GRE_CSUM we have to use GSO_PARTIAL.
- */
- net_dev->gso_partial_features |= NETIF_F_GSO_GRE_CSUM;
- }
efx->num_mac_stats = MCDI_WORD(outbuf,
GET_CAPABILITIES_V4_OUT_MAC_STATS_NUM_STATS);
netif_dbg(efx, probe, efx->net_dev,
"firmware reports num_mac_stats = %u\n",
efx->num_mac_stats);
+
+ /* Current EF100 hardware supports vDPA on VFs only, requires MCDI v2
+ * and Firmware's capability to proxy MCDI commands from PF to VF
+ */
+ if (IS_ENABLED(CONFIG_SFC_VDPA)) {
+ nic_data->vdpa_supported = efx->type->is_vf &&
+ (efx->type->mcdi_max_ver > 1) &&
+ efx_ef100_has_cap(nic_data->datapath_caps3,
+ CLIENT_CMD_VF_PROXY);
+ }
+
return 0;
}

@@ -820,14 +817,12 @@ int efx_ef100_set_bar_config(struct efx_nic *efx,
if (WARN_ON_ONCE(nic_data->bar_config > EF100_BAR_CONFIG_VDPA))
return -EINVAL;

- /* Current EF100 hardware supports vDPA on VFs only */
- if (IS_ENABLED(CONFIG_SFC_VDPA) &&
- new_config == EF100_BAR_CONFIG_VDPA &&
- !efx->type->is_vf) {
- pci_err(efx->pci_dev, "vdpa over PF not supported : %s",
- efx->name);
+#ifdef CONFIG_SFC_VDPA
+ if (new_config == EF100_BAR_CONFIG_VDPA && !nic_data->vdpa_supported) {
+ pci_err(efx->pci_dev, "vdpa not supported on %s", efx->name);
return -EOPNOTSUPP;
}
+#endif

mutex_lock(&nic_data->bar_config_lock);
old_config = nic_data->bar_config;
@@ -1203,6 +1198,12 @@ static int ef100_probe_main(struct efx_nic *efx)
goto fail;
}

+ rc = efx_ef100_init_datapath_caps(efx);
+ if (rc) {
+ pci_info(efx->pci_dev, "Unable to initialize datapath caps\n");
+ goto fail;
+ }
+
return 0;
fail:
return rc;
diff --git a/drivers/net/ethernet/sfc/ef100_nic.h b/drivers/net/ethernet/sfc/ef100_nic.h
index 02e5ab4e9f1f..a01e9d643ccd 100644
--- a/drivers/net/ethernet/sfc/ef100_nic.h
+++ b/drivers/net/ethernet/sfc/ef100_nic.h
@@ -77,6 +77,9 @@ struct ef100_nic_data {
u32 datapath_caps3;
unsigned int pf_index;
u16 warm_boot_count;
+#ifdef CONFIG_SFC_VDPA
+ bool vdpa_supported; /* true if vdpa is supported on this PCIe FN */
+#endif
u8 port_id[ETH_ALEN];
DECLARE_BITMAP(evq_phases, EFX_MAX_CHANNELS);
enum ef100_bar_config bar_config;
@@ -96,9 +99,8 @@ struct ef100_nic_data {
};

#define efx_ef100_has_cap(caps, flag) \
- (!!((caps) & BIT_ULL(MC_CMD_GET_CAPABILITIES_V4_OUT_ ## flag ## _LBN)))
+ (!!((caps) & BIT_ULL(MC_CMD_GET_CAPABILITIES_V7_OUT_ ## flag ## _LBN)))

-int efx_ef100_init_datapath_caps(struct efx_nic *efx);
int ef100_phy_probe(struct efx_nic *efx);
int ef100_filter_table_probe(struct efx_nic *efx);

--
2.30.1