sfc: determine representee m-port for EF100 representors

An MAE port, or m-port, is a port (source/destination for traffic) on
 the Match-Action Engine (the internal switch on EF100).
Representors will use their representee's m-port for two purposes: as
 a destination override on TX from the representor, and as a source
 match in 'default rules' to steer representee traffic (when not
 matched by e.g. a TC flower rule) to representor RX via the parent
 PF's receive queue.
Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/sfc/Makefile

@@ -8,7 +8,7 @@ sfc-y			+= efx.o efx_common.o efx_channels.o nic.o \
 			   ef100.o ef100_nic.o ef100_netdev.o \
 			   ef100_ethtool.o ef100_rx.o ef100_tx.o
 sfc-$(CONFIG_SFC_MTD)	+= mtd.o
-sfc-$(CONFIG_SFC_SRIOV)	+= sriov.o ef10_sriov.o ef100_sriov.o ef100_rep.o
+sfc-$(CONFIG_SFC_SRIOV)	+= sriov.o ef10_sriov.o ef100_sriov.o ef100_rep.o mae.o
 
 obj-$(CONFIG_SFC)	+= sfc.o
 

drivers/net/ethernet/sfc/ef100_rep.c

@@ -11,6 +11,7 @@
 
 #include "ef100_rep.h"
 #include "ef100_nic.h"
+#include "mae.h"
 
 #define EFX_EF100_REP_DRIVER	"efx_ef100_rep"
 
@@ -124,6 +125,25 @@ static struct efx_rep *efx_ef100_rep_create_netdev(struct efx_nic *efx,
 	return ERR_PTR(rc);
 }
 
+static int efx_ef100_configure_rep(struct efx_rep *efv)
+{
+	struct efx_nic *efx = efv->parent;
+	u32 selector;
+	int rc;
+
+	/* Construct mport selector for corresponding VF */
+	efx_mae_mport_vf(efx, efv->idx, &selector);
+	/* Look up actual mport ID */
+	rc = efx_mae_lookup_mport(efx, selector, &efv->mport);
+	if (rc)
+		return rc;
+	pci_dbg(efx->pci_dev, "VF %u has mport ID %#x\n", efv->idx, efv->mport);
+	/* mport label should fit in 16 bits */
+	WARN_ON(efv->mport >> 16);
+
+	return 0;
+}
+
 static void efx_ef100_rep_destroy_netdev(struct efx_rep *efv)
 {
 	struct efx_nic *efx = efv->parent;
@@ -147,6 +167,13 @@ int efx_ef100_vfrep_create(struct efx_nic *efx, unsigned int i)
 			rc);
 		return rc;
 	}
+	rc = efx_ef100_configure_rep(efv);
+	if (rc) {
+		pci_err(efx->pci_dev,
+			"Failed to configure representor for VF %d, rc %d\n",
+			i, rc);
+		goto fail;
+	}
 	rc = register_netdev(efv->net_dev);
 	if (rc) {
 		pci_err(efx->pci_dev,

drivers/net/ethernet/sfc/ef100_rep.h

@@ -21,6 +21,7 @@
  * @parent: the efx PF which manages this representor
  * @net_dev: representor netdevice
  * @msg_enable: log message enable flags
+ * @mport: m-port ID of corresponding VF
  * @idx: VF index
  * @list: entry on efx->vf_reps
  */
@@ -28,6 +29,7 @@ struct efx_rep {
 	struct efx_nic *parent;
 	struct net_device *net_dev;
 	u32 msg_enable;
+	u32 mport;
 	unsigned int idx;
 	struct list_head list;
 };

drivers/net/ethernet/sfc/mae.c

+// SPDX-License-Identifier: GPL-2.0-only
+/****************************************************************************
+ * Driver for Solarflare network controllers and boards
+ * Copyright 2019 Solarflare Communications Inc.
+ * Copyright 2020-2022 Xilinx Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, incorporated herein by reference.
+ */
+
+#include "mae.h"
+#include "mcdi.h"
+#include "mcdi_pcol.h"
+
+void efx_mae_mport_vf(struct efx_nic *efx __always_unused, u32 vf_id, u32 *out)
+{
+	efx_dword_t mport;
+
+	EFX_POPULATE_DWORD_3(mport,
+			     MAE_MPORT_SELECTOR_TYPE, MAE_MPORT_SELECTOR_TYPE_FUNC,
+			     MAE_MPORT_SELECTOR_FUNC_PF_ID, MAE_MPORT_SELECTOR_FUNC_PF_ID_CALLER,
+			     MAE_MPORT_SELECTOR_FUNC_VF_ID, vf_id);
+	*out = EFX_DWORD_VAL(mport);
+}
+
+/* id is really only 24 bits wide */
+int efx_mae_lookup_mport(struct efx_nic *efx, u32 selector, u32 *id)
+{
+	MCDI_DECLARE_BUF(outbuf, MC_CMD_MAE_MPORT_LOOKUP_OUT_LEN);
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_MAE_MPORT_LOOKUP_IN_LEN);
+	size_t outlen;
+	int rc;
+
+	MCDI_SET_DWORD(inbuf, MAE_MPORT_LOOKUP_IN_MPORT_SELECTOR, selector);
+	rc = efx_mcdi_rpc(efx, MC_CMD_MAE_MPORT_LOOKUP, inbuf, sizeof(inbuf),
+			  outbuf, sizeof(outbuf), &outlen);
+	if (rc)
+		return rc;
+	if (outlen < sizeof(outbuf))
+		return -EIO;
+	*id = MCDI_DWORD(outbuf, MAE_MPORT_LOOKUP_OUT_MPORT_ID);
+	return 0;
+}

drivers/net/ethernet/sfc/mae.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+/****************************************************************************
+ * Driver for Solarflare network controllers and boards
+ * Copyright 2019 Solarflare Communications Inc.
+ * Copyright 2020-2022 Xilinx Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, incorporated herein by reference.
+ */
+
+#ifndef EF100_MAE_H
+#define EF100_MAE_H
+/* MCDI interface for the ef100 Match-Action Engine */
+
+#include "net_driver.h"
+
+void efx_mae_mport_vf(struct efx_nic *efx, u32 vf_id, u32 *out);
+
+int efx_mae_lookup_mport(struct efx_nic *efx, u32 selector, u32 *id);
+
+#endif /* EF100_MAE_H */