Merge branch 'sfc-TC-offload-counters'

Edward Cree says:

====================
sfc: TC offload counters

EF100 hardware supports attaching counters to action-sets in the MAE.
Use these counters to implement stats for TC flower offload.

The counters are delivered to the host over a special hardware RX queue
 which should only ever receive counter update messages, not 'real'
 network packets.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/sfc/Makefile

@@ -9,7 +9,7 @@ sfc-y			+= efx.o efx_common.o efx_channels.o nic.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 \
-                           mae.o tc.o tc_bindings.o
+                           mae.o tc.o tc_bindings.o tc_counters.o
 
 obj-$(CONFIG_SFC)	+= sfc.o
 

drivers/net/ethernet/sfc/ef100_rx.c

@@ -21,7 +21,7 @@
 /* Get the value of a field in the RX prefix */
 #define PREFIX_OFFSET_W(_f)	(ESF_GZ_RX_PREFIX_ ## _f ## _LBN / 32)
 #define PREFIX_OFFSET_B(_f)	(ESF_GZ_RX_PREFIX_ ## _f ## _LBN % 32)
-#define PREFIX_WIDTH_MASK(_f)	((1UL << ESF_GZ_RX_PREFIX_ ## _f ## _WIDTH) - 1)
+#define PREFIX_WIDTH_MASK(_f)	((1ULL << ESF_GZ_RX_PREFIX_ ## _f ## _WIDTH) - 1)
 #define PREFIX_WORD(_p, _f)	le32_to_cpu((__force __le32)(_p)[PREFIX_OFFSET_W(_f)])
 #define PREFIX_FIELD(_p, _f)	((PREFIX_WORD(_p, _f) >> PREFIX_OFFSET_B(_f)) & \
 				 PREFIX_WIDTH_MASK(_f))
@@ -67,6 +67,13 @@ void __ef100_rx_packet(struct efx_channel *channel)
 
 	prefix = (u32 *)(eh - ESE_GZ_RX_PKT_PREFIX_LEN);
 
+	if (channel->type->receive_raw) {
+		u32 mark = PREFIX_FIELD(prefix, USER_MARK);
+
+		if (channel->type->receive_raw(rx_queue, mark))
+			return; /* packet was consumed */
+	}
+
 	if (ef100_has_fcs_error(channel, prefix) &&
 	    unlikely(!(efx->net_dev->features & NETIF_F_RXALL)))
 		goto out;
@@ -183,24 +190,32 @@ void efx_ef100_ev_rx(struct efx_channel *channel, const efx_qword_t *p_event)
 
 void ef100_rx_write(struct efx_rx_queue *rx_queue)
 {
+	unsigned int notified_count = rx_queue->notified_count;
 	struct efx_rx_buffer *rx_buf;
 	unsigned int idx;
 	efx_qword_t *rxd;
 	efx_dword_t rxdb;
 
-	while (rx_queue->notified_count != rx_queue->added_count) {
-		idx = rx_queue->notified_count & rx_queue->ptr_mask;
+	while (notified_count != rx_queue->added_count) {
+		idx = notified_count & rx_queue->ptr_mask;
 		rx_buf = efx_rx_buffer(rx_queue, idx);
 		rxd = efx_rx_desc(rx_queue, idx);
 
 		EFX_POPULATE_QWORD_1(*rxd, ESF_GZ_RX_BUF_ADDR, rx_buf->dma_addr);
 
-		++rx_queue->notified_count;
+		++notified_count;
 	}
+	if (notified_count == rx_queue->notified_count)
+		return;
 
 	wmb();
 	EFX_POPULATE_DWORD_1(rxdb, ERF_GZ_RX_RING_PIDX,
 			     rx_queue->added_count & rx_queue->ptr_mask);
 	efx_writed_page(rx_queue->efx, &rxdb,
 			ER_GZ_RX_RING_DOORBELL, efx_rx_queue_index(rx_queue));
+	if (rx_queue->grant_credits)
+		wmb();
+	rx_queue->notified_count = notified_count;
+	if (rx_queue->grant_credits)
+		schedule_work(&rx_queue->grant_work);
 }

drivers/net/ethernet/sfc/efx_channels.c

@@ -1119,6 +1119,8 @@ void efx_start_channels(struct efx_nic *efx)
 	struct efx_channel *channel;
 
 	efx_for_each_channel_rev(channel, efx) {
+		if (channel->type->start)
+			channel->type->start(channel);
 		efx_for_each_channel_tx_queue(tx_queue, channel) {
 			efx_init_tx_queue(tx_queue);
 			atomic_inc(&efx->active_queues);
@@ -1143,8 +1145,13 @@ void efx_stop_channels(struct efx_nic *efx)
 	struct efx_channel *channel;
 	int rc = 0;
 
-	/* Stop RX refill */
+	/* Stop special channels and RX refill.
+	 * The channel's stop has to be called first, since it might wait
+	 * for a sentinel RX to indicate the channel has fully drained.
+	 */
 	efx_for_each_channel(channel, efx) {
+		if (channel->type->stop)
+			channel->type->stop(channel);
 		efx_for_each_channel_rx_queue(rx_queue, channel)
 			rx_queue->refill_enabled = false;
 	}

drivers/net/ethernet/sfc/mae.c

@@ -112,6 +112,117 @@ int efx_mae_lookup_mport(struct efx_nic *efx, u32 selector, u32 *id)
 	return 0;
 }
 
+int efx_mae_start_counters(struct efx_nic *efx, struct efx_rx_queue *rx_queue)
+{
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_MAE_COUNTERS_STREAM_START_V2_IN_LEN);
+	MCDI_DECLARE_BUF(outbuf, MC_CMD_MAE_COUNTERS_STREAM_START_OUT_LEN);
+	u32 out_flags;
+	size_t outlen;
+	int rc;
+
+	MCDI_SET_WORD(inbuf, MAE_COUNTERS_STREAM_START_V2_IN_QID,
+		      efx_rx_queue_index(rx_queue));
+	MCDI_SET_WORD(inbuf, MAE_COUNTERS_STREAM_START_V2_IN_PACKET_SIZE,
+		      efx->net_dev->mtu);
+	MCDI_SET_DWORD(inbuf, MAE_COUNTERS_STREAM_START_V2_IN_COUNTER_TYPES_MASK,
+		       BIT(MAE_COUNTER_TYPE_AR) | BIT(MAE_COUNTER_TYPE_CT) |
+		       BIT(MAE_COUNTER_TYPE_OR));
+	rc = efx_mcdi_rpc(efx, MC_CMD_MAE_COUNTERS_STREAM_START,
+			  inbuf, sizeof(inbuf), outbuf, sizeof(outbuf), &outlen);
+	if (rc)
+		return rc;
+	if (outlen < sizeof(outbuf))
+		return -EIO;
+	out_flags = MCDI_DWORD(outbuf, MAE_COUNTERS_STREAM_START_OUT_FLAGS);
+	if (out_flags & BIT(MC_CMD_MAE_COUNTERS_STREAM_START_OUT_USES_CREDITS_OFST)) {
+		netif_dbg(efx, drv, efx->net_dev,
+			  "MAE counter stream uses credits\n");
+		rx_queue->grant_credits = true;
+		out_flags &= ~BIT(MC_CMD_MAE_COUNTERS_STREAM_START_OUT_USES_CREDITS_OFST);
+	}
+	if (out_flags) {
+		netif_err(efx, drv, efx->net_dev,
+			  "MAE counter stream start: unrecognised flags %x\n",
+			  out_flags);
+		goto out_stop;
+	}
+	return 0;
+out_stop:
+	efx_mae_stop_counters(efx, rx_queue);
+	return -EOPNOTSUPP;
+}
+
+static bool efx_mae_counters_flushed(u32 *flush_gen, u32 *seen_gen)
+{
+	int i;
+
+	for (i = 0; i < EFX_TC_COUNTER_TYPE_MAX; i++)
+		if ((s32)(flush_gen[i] - seen_gen[i]) > 0)
+			return false;
+	return true;
+}
+
+int efx_mae_stop_counters(struct efx_nic *efx, struct efx_rx_queue *rx_queue)
+{
+	MCDI_DECLARE_BUF(outbuf, MC_CMD_MAE_COUNTERS_STREAM_STOP_V2_OUT_LENMAX);
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_MAE_COUNTERS_STREAM_STOP_IN_LEN);
+	size_t outlen;
+	int rc, i;
+
+	MCDI_SET_WORD(inbuf, MAE_COUNTERS_STREAM_STOP_IN_QID,
+		      efx_rx_queue_index(rx_queue));
+	rc = efx_mcdi_rpc(efx, MC_CMD_MAE_COUNTERS_STREAM_STOP,
+			  inbuf, sizeof(inbuf), outbuf, sizeof(outbuf), &outlen);
+
+	if (rc)
+		return rc;
+
+	netif_dbg(efx, drv, efx->net_dev, "Draining counters:\n");
+	/* Only process received generation counts */
+	for (i = 0; (i < (outlen / 4)) && (i < EFX_TC_COUNTER_TYPE_MAX); i++) {
+		efx->tc->flush_gen[i] = MCDI_ARRAY_DWORD(outbuf,
+							 MAE_COUNTERS_STREAM_STOP_V2_OUT_GENERATION_COUNT,
+							 i);
+		netif_dbg(efx, drv, efx->net_dev,
+			  "\ttype %u, awaiting gen %u\n", i,
+			  efx->tc->flush_gen[i]);
+	}
+
+	efx->tc->flush_counters = true;
+
+	/* Drain can take up to 2 seconds owing to FWRIVERHD-2884; whatever
+	 * timeout we use, that delay is added to unload on nonresponsive
+	 * hardware, so 2500ms seems like a reasonable compromise.
+	 */
+	if (!wait_event_timeout(efx->tc->flush_wq,
+				efx_mae_counters_flushed(efx->tc->flush_gen,
+							 efx->tc->seen_gen),
+				msecs_to_jiffies(2500)))
+		netif_warn(efx, drv, efx->net_dev,
+			   "Failed to drain counters RXQ, FW may be unhappy\n");
+
+	efx->tc->flush_counters = false;
+
+	return rc;
+}
+
+void efx_mae_counters_grant_credits(struct work_struct *work)
+{
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_MAE_COUNTERS_STREAM_GIVE_CREDITS_IN_LEN);
+	struct efx_rx_queue *rx_queue = container_of(work, struct efx_rx_queue,
+						     grant_work);
+	struct efx_nic *efx = rx_queue->efx;
+	unsigned int credits;
+
+	BUILD_BUG_ON(MC_CMD_MAE_COUNTERS_STREAM_GIVE_CREDITS_OUT_LEN);
+	credits = READ_ONCE(rx_queue->notified_count) - rx_queue->granted_count;
+	MCDI_SET_DWORD(inbuf, MAE_COUNTERS_STREAM_GIVE_CREDITS_IN_NUM_CREDITS,
+		       credits);
+	if (!efx_mcdi_rpc(efx, MC_CMD_MAE_COUNTERS_STREAM_GIVE_CREDITS,
+			  inbuf, sizeof(inbuf), NULL, 0, NULL))
+		rx_queue->granted_count += credits;
+}
+
 static int efx_mae_get_basic_caps(struct efx_nic *efx, struct mae_caps *caps)
 {
 	MCDI_DECLARE_BUF(outbuf, MC_CMD_MAE_GET_CAPS_OUT_LEN);
@@ -323,6 +434,57 @@ int efx_mae_match_check_caps(struct efx_nic *efx,
 #undef CHECK_BIT
 #undef CHECK
 
+int efx_mae_allocate_counter(struct efx_nic *efx, struct efx_tc_counter *cnt)
+{
+	MCDI_DECLARE_BUF(outbuf, MC_CMD_MAE_COUNTER_ALLOC_OUT_LEN(1));
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_MAE_COUNTER_ALLOC_V2_IN_LEN);
+	size_t outlen;
+	int rc;
+
+	if (!cnt)
+		return -EINVAL;
+
+	MCDI_SET_DWORD(inbuf, MAE_COUNTER_ALLOC_V2_IN_REQUESTED_COUNT, 1);
+	MCDI_SET_DWORD(inbuf, MAE_COUNTER_ALLOC_V2_IN_COUNTER_TYPE, cnt->type);
+	rc = efx_mcdi_rpc(efx, MC_CMD_MAE_COUNTER_ALLOC, inbuf, sizeof(inbuf),
+			  outbuf, sizeof(outbuf), &outlen);
+	if (rc)
+		return rc;
+	/* pcol says this can't happen, since count is 1 */
+	if (outlen < sizeof(outbuf))
+		return -EIO;
+	cnt->fw_id = MCDI_DWORD(outbuf, MAE_COUNTER_ALLOC_OUT_COUNTER_ID);
+	cnt->gen = MCDI_DWORD(outbuf, MAE_COUNTER_ALLOC_OUT_GENERATION_COUNT);
+	return 0;
+}
+
+int efx_mae_free_counter(struct efx_nic *efx, struct efx_tc_counter *cnt)
+{
+	MCDI_DECLARE_BUF(outbuf, MC_CMD_MAE_COUNTER_FREE_OUT_LEN(1));
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_MAE_COUNTER_FREE_V2_IN_LEN);
+	size_t outlen;
+	int rc;
+
+	MCDI_SET_DWORD(inbuf, MAE_COUNTER_FREE_V2_IN_COUNTER_ID_COUNT, 1);
+	MCDI_SET_DWORD(inbuf, MAE_COUNTER_FREE_V2_IN_FREE_COUNTER_ID, cnt->fw_id);
+	MCDI_SET_DWORD(inbuf, MAE_COUNTER_FREE_V2_IN_COUNTER_TYPE, cnt->type);
+	rc = efx_mcdi_rpc(efx, MC_CMD_MAE_COUNTER_FREE, inbuf, sizeof(inbuf),
+			  outbuf, sizeof(outbuf), &outlen);
+	if (rc)
+		return rc;
+	/* pcol says this can't happen, since count is 1 */
+	if (outlen < sizeof(outbuf))
+		return -EIO;
+	/* FW freed a different ID than we asked for, should also never happen.
+	 * Warn because it means we've now got a different idea to the FW of
+	 * what counters exist, which could cause mayhem later.
+	 */
+	if (WARN_ON(MCDI_DWORD(outbuf, MAE_COUNTER_FREE_OUT_FREED_COUNTER_ID) !=
+		    cnt->fw_id))
+		return -EIO;
+	return 0;
+}
+
 static bool efx_mae_asl_id(u32 id)
 {
 	return !!(id & BIT(31));
@@ -339,8 +501,12 @@ int efx_mae_alloc_action_set(struct efx_nic *efx, struct efx_tc_action_set *act)
 		       MC_CMD_MAE_MAC_ADDR_ALLOC_OUT_MAC_ID_NULL);
 	MCDI_SET_DWORD(inbuf, MAE_ACTION_SET_ALLOC_IN_DST_MAC_ID,
 		       MC_CMD_MAE_MAC_ADDR_ALLOC_OUT_MAC_ID_NULL);
-	MCDI_SET_DWORD(inbuf, MAE_ACTION_SET_ALLOC_IN_COUNTER_ID,
-		       MC_CMD_MAE_COUNTER_ALLOC_OUT_COUNTER_ID_NULL);
+	if (act->count && !WARN_ON(!act->count->cnt))
+		MCDI_SET_DWORD(inbuf, MAE_ACTION_SET_ALLOC_IN_COUNTER_ID,
+			       act->count->cnt->fw_id);
+	else
+		MCDI_SET_DWORD(inbuf, MAE_ACTION_SET_ALLOC_IN_COUNTER_ID,
+			       MC_CMD_MAE_COUNTER_ALLOC_OUT_COUNTER_ID_NULL);
 	MCDI_SET_DWORD(inbuf, MAE_ACTION_SET_ALLOC_IN_COUNTER_LIST_ID,
 		       MC_CMD_MAE_COUNTER_LIST_ALLOC_OUT_COUNTER_LIST_ID_NULL);
 	MCDI_SET_DWORD(inbuf, MAE_ACTION_SET_ALLOC_IN_ENCAP_HEADER_ID,

drivers/net/ethernet/sfc/mae.h

@@ -27,6 +27,10 @@ void efx_mae_mport_mport(struct efx_nic *efx, u32 mport_id, u32 *out);
 
 int efx_mae_lookup_mport(struct efx_nic *efx, u32 selector, u32 *id);
 
+int efx_mae_start_counters(struct efx_nic *efx, struct efx_rx_queue *rx_queue);
+int efx_mae_stop_counters(struct efx_nic *efx, struct efx_rx_queue *rx_queue);
+void efx_mae_counters_grant_credits(struct work_struct *work);
+
 #define MAE_NUM_FIELDS	(MAE_FIELD_ENC_VNET_ID + 1)
 
 struct mae_caps {
@@ -41,6 +45,9 @@ int efx_mae_match_check_caps(struct efx_nic *efx,
 			     const struct efx_tc_match_fields *mask,
 			     struct netlink_ext_ack *extack);
 
+int efx_mae_allocate_counter(struct efx_nic *efx, struct efx_tc_counter *cnt);
+int efx_mae_free_counter(struct efx_nic *efx, struct efx_tc_counter *cnt);
+
 int efx_mae_alloc_action_set(struct efx_nic *efx, struct efx_tc_action_set *act);
 int efx_mae_free_action_set(struct efx_nic *efx, u32 fw_id);
 

drivers/net/ethernet/sfc/mae_counter_format.h

@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/****************************************************************************
+ * Driver for Solarflare network controllers and boards
+ * Copyright 2020 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.
+ */
+
+/* Format of counter packets (version 2) from the ef100 Match-Action Engine */
+
+#ifndef EFX_MAE_COUNTER_FORMAT_H
+#define EFX_MAE_COUNTER_FORMAT_H
+
+
+/*------------------------------------------------------------*/
+/*
+ * ER_RX_SL_PACKETISER_HEADER_WORD(160bit):
+ * 
+ */
+#define ER_RX_SL_PACKETISER_HEADER_WORD_SIZE 20
+#define ER_RX_SL_PACKETISER_HEADER_WORD_WIDTH 160
+
+#define ERF_SC_PACKETISER_HEADER_VERSION_LBN 0
+#define ERF_SC_PACKETISER_HEADER_VERSION_WIDTH 8
+#define ERF_SC_PACKETISER_HEADER_VERSION_VALUE 2
+#define ERF_SC_PACKETISER_HEADER_IDENTIFIER_LBN 8
+#define ERF_SC_PACKETISER_HEADER_IDENTIFIER_WIDTH 8
+#define ERF_SC_PACKETISER_HEADER_IDENTIFIER_AR 0
+#define ERF_SC_PACKETISER_HEADER_IDENTIFIER_CT 1
+#define ERF_SC_PACKETISER_HEADER_IDENTIFIER_OR 2
+#define ERF_SC_PACKETISER_HEADER_HEADER_OFFSET_LBN 16
+#define ERF_SC_PACKETISER_HEADER_HEADER_OFFSET_WIDTH 8
+#define ERF_SC_PACKETISER_HEADER_HEADER_OFFSET_DEFAULT 0x4
+#define ERF_SC_PACKETISER_HEADER_PAYLOAD_OFFSET_LBN 24
+#define ERF_SC_PACKETISER_HEADER_PAYLOAD_OFFSET_WIDTH 8
+#define ERF_SC_PACKETISER_HEADER_PAYLOAD_OFFSET_DEFAULT 0x14
+#define ERF_SC_PACKETISER_HEADER_INDEX_LBN 32
+#define ERF_SC_PACKETISER_HEADER_INDEX_WIDTH 16
+#define ERF_SC_PACKETISER_HEADER_COUNT_LBN 48
+#define ERF_SC_PACKETISER_HEADER_COUNT_WIDTH 16
+#define ERF_SC_PACKETISER_HEADER_RESERVED_0_LBN 64
+#define ERF_SC_PACKETISER_HEADER_RESERVED_0_WIDTH 32
+#define ERF_SC_PACKETISER_HEADER_RESERVED_1_LBN 96
+#define ERF_SC_PACKETISER_HEADER_RESERVED_1_WIDTH 32
+#define ERF_SC_PACKETISER_HEADER_RESERVED_2_LBN 128
+#define ERF_SC_PACKETISER_HEADER_RESERVED_2_WIDTH 32
+
+
+/*------------------------------------------------------------*/
+/*
+ * ER_RX_SL_PACKETISER_PAYLOAD_WORD(128bit):
+ * 
+ */
+#define ER_RX_SL_PACKETISER_PAYLOAD_WORD_SIZE 16
+#define ER_RX_SL_PACKETISER_PAYLOAD_WORD_WIDTH 128
+
+#define ERF_SC_PACKETISER_PAYLOAD_COUNTER_INDEX_LBN 0
+#define ERF_SC_PACKETISER_PAYLOAD_COUNTER_INDEX_WIDTH 24
+#define ERF_SC_PACKETISER_PAYLOAD_RESERVED_LBN 24
+#define ERF_SC_PACKETISER_PAYLOAD_RESERVED_WIDTH 8
+#define ERF_SC_PACKETISER_PAYLOAD_PACKET_COUNT_OFST 4
+#define ERF_SC_PACKETISER_PAYLOAD_PACKET_COUNT_SIZE 6
+#define ERF_SC_PACKETISER_PAYLOAD_PACKET_COUNT_LBN 32
+#define ERF_SC_PACKETISER_PAYLOAD_PACKET_COUNT_WIDTH 48
+#define ERF_SC_PACKETISER_PAYLOAD_BYTE_COUNT_OFST 10
+#define ERF_SC_PACKETISER_PAYLOAD_BYTE_COUNT_SIZE 6
+#define ERF_SC_PACKETISER_PAYLOAD_BYTE_COUNT_LBN 80
+#define ERF_SC_PACKETISER_PAYLOAD_BYTE_COUNT_WIDTH 48
+
+
+#endif /* EFX_MAE_COUNTER_FORMAT_H */

drivers/net/ethernet/sfc/mcdi.h

@@ -221,6 +221,11 @@ void efx_mcdi_sensor_event(struct efx_nic *efx, efx_qword_t *ev);
 #define MCDI_BYTE(_buf, _field)						\
 	((void)BUILD_BUG_ON_ZERO(MC_CMD_ ## _field ## _LEN != 1),	\
 	 *MCDI_PTR(_buf, _field))
+#define MCDI_SET_WORD(_buf, _field, _value) do {			\
+	BUILD_BUG_ON(MC_CMD_ ## _field ## _LEN != 2);			\
+	BUILD_BUG_ON(MC_CMD_ ## _field ## _OFST & 1);			\
+	*(__force __le16 *)MCDI_PTR(_buf, _field) = cpu_to_le16(_value);\
+	} while (0)
 #define MCDI_WORD(_buf, _field)						\
 	((u16)BUILD_BUG_ON_ZERO(MC_CMD_ ## _field ## _LEN != 2) +	\
 	 le16_to_cpu(*(__force const __le16 *)MCDI_PTR(_buf, _field)))