sfc: add ndo_set_vf_link_state() function for EF10

Exercised with
"ip link set <PF intf> vf <vf_i> state {auto|enable|disable}"
Sets the reporting policy for VF link state to either
 - mirror physical link state
 - always up
 - always down

get VF link state mode in efx_ef10_sriov_get_vf_config

Exercised by
"ip link show <PF intf>";
output will include a line like
vf 0 MAC 12:34:56:78:9a:bc, link-state auto

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/sfc/ef10_sriov.c b/drivers/net/ethernet/sfc/ef10_sriov.c
index 49238fc..edc34f3 100644
--- a/drivers/net/ethernet/sfc/ef10_sriov.c
+++ b/drivers/net/ethernet/sfc/ef10_sriov.c
@@ -667,11 +667,37 @@
 	return rc ? rc : rc2;
 }
 
+int efx_ef10_sriov_set_vf_link_state(struct efx_nic *efx, int vf_i,
+				     int link_state)
+{
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_LINK_STATE_MODE_IN_LEN);
+	struct efx_ef10_nic_data *nic_data = efx->nic_data;
+
+	BUILD_BUG_ON(IFLA_VF_LINK_STATE_AUTO !=
+		     MC_CMD_LINK_STATE_MODE_IN_LINK_STATE_AUTO);
+	BUILD_BUG_ON(IFLA_VF_LINK_STATE_ENABLE !=
+		     MC_CMD_LINK_STATE_MODE_IN_LINK_STATE_UP);
+	BUILD_BUG_ON(IFLA_VF_LINK_STATE_DISABLE !=
+		     MC_CMD_LINK_STATE_MODE_IN_LINK_STATE_DOWN);
+	MCDI_POPULATE_DWORD_2(inbuf, LINK_STATE_MODE_IN_FUNCTION,
+			      LINK_STATE_MODE_IN_FUNCTION_PF,
+			      nic_data->pf_index,
+			      LINK_STATE_MODE_IN_FUNCTION_VF, vf_i);
+	MCDI_SET_DWORD(inbuf, LINK_STATE_MODE_IN_NEW_MODE, link_state);
+	return efx_mcdi_rpc(efx, MC_CMD_LINK_STATE_MODE, inbuf, sizeof(inbuf),
+			    NULL, 0, NULL); /* don't care what old mode was */
+}
+
 int efx_ef10_sriov_get_vf_config(struct efx_nic *efx, int vf_i,
 				 struct ifla_vf_info *ivf)
 {
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_LINK_STATE_MODE_IN_LEN);
+	MCDI_DECLARE_BUF(outbuf, MC_CMD_LINK_STATE_MODE_OUT_LEN);
+
 	struct efx_ef10_nic_data *nic_data = efx->nic_data;
 	struct ef10_vf *vf;
+	size_t outlen;
+	int rc;
 
 	if (vf_i >= efx->vf_count)
 		return -EINVAL;
@@ -688,5 +714,19 @@
 	ivf->vlan = (vf->vlan == EFX_EF10_NO_VLAN) ? 0 : vf->vlan;
 	ivf->qos = 0;
 
+	MCDI_POPULATE_DWORD_2(inbuf, LINK_STATE_MODE_IN_FUNCTION,
+			      LINK_STATE_MODE_IN_FUNCTION_PF,
+			      nic_data->pf_index,
+			      LINK_STATE_MODE_IN_FUNCTION_VF, vf_i);
+	MCDI_SET_DWORD(inbuf, LINK_STATE_MODE_IN_NEW_MODE,
+		       MC_CMD_LINK_STATE_MODE_IN_DO_NOT_CHANGE);
+	rc = efx_mcdi_rpc(efx, MC_CMD_LINK_STATE_MODE, inbuf, sizeof(inbuf),
+			  outbuf, sizeof(outbuf), &outlen);
+	if (rc)
+		return rc;
+	if (outlen < MC_CMD_LINK_STATE_MODE_OUT_LEN)
+		return -EIO;
+	ivf->linkstate = MCDI_DWORD(outbuf, LINK_STATE_MODE_OUT_OLD_MODE);
+
 	return 0;
 }