2 files changed, 18 insertions, 2 deletions

diff --git a/drivers/net/ethernet/sfc/mcdi.c b/drivers/net/ethernet/sfc/mcdi.c
index d317dfdee845..d608838f6729 100644
--- a/drivers/net/ethernet/sfc/mcdi.c
+++ b/drivers/net/ethernet/sfc/mcdi.c
@@ -1132,13 +1132,27 @@ static int efx_mcdi_drv_attach(struct efx_nic *efx, bool driver_operating,
                 goto fail;
         }
 
+        if (driver_operating) {
+                if (outlen >= MC_CMD_DRV_ATTACH_EXT_OUT_LEN) {
+                        efx->mcdi->fn_flags =
+                                MCDI_DWORD(outbuf,
+                                           DRV_ATTACH_EXT_OUT_FUNC_FLAGS);
+                } else {
+                        /* Synthesise flags for Siena */
+                        efx->mcdi->fn_flags =
+                                1 << MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_LINKCTRL |
+                                1 << MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_TRUSTED |
+                                (efx_port_num(efx) == 0) <<
+                                MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_PRIMARY;
+                }
+        }
+
         /* We currently assume we have control of the external link
          * and are completely trusted by firmware.  Abort probing
          * if that's not true for this function.
          */
         if (driver_operating &&
-            outlen >= MC_CMD_DRV_ATTACH_EXT_OUT_LEN &&
-            (MCDI_DWORD(outbuf, DRV_ATTACH_EXT_OUT_FUNC_FLAGS) &
+            (efx->mcdi->fn_flags &
              (1 << MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_LINKCTRL |
               1 << MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_TRUSTED)) !=
             (1 << MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_LINKCTRL |
diff --git a/drivers/net/ethernet/sfc/mcdi.h b/drivers/net/ethernet/sfc/mcdi.h
index 171f5f58f84a..52931aebf3c3 100644
--- a/drivers/net/ethernet/sfc/mcdi.h
+++ b/drivers/net/ethernet/sfc/mcdi.h
@@ -94,12 +94,14 @@ struct efx_mcdi_mtd_partition {
  * struct efx_mcdi_data - extra state for NICs that implement MCDI
  * @iface: Interface/protocol state
  * @hwmon: Hardware monitor state
+ * @fn_flags: Flags for this function, as returned by %MC_CMD_DRV_ATTACH.
  */
 struct efx_mcdi_data {
         struct efx_mcdi_iface iface;
 #ifdef CONFIG_SFC_MCDI_MON
         struct efx_mcdi_mon hwmon;
 #endif
+        u32 fn_flags;
 };
 
 #ifdef CONFIG_SFC_MCDI_MON