net: dpaa2-eth: add support for multiple buffer pools per DPNI

This patch allows the configuration of multiple buffer pools associated
with a single DPNI object, each distinct DPBP object not necessarily
shared among all queues.
The user can interogate both the number of buffer pools and the buffer
count in each buffer pool by using the .get_ethtool_stats() callback.
Signed-off-by: Robert-Ionut Alexa <robert-ionut.alexa@nxp.com>
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h

 /* SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause) */
 /* Copyright 2014-2016 Freescale Semiconductor Inc.
- * Copyright 2016-2020 NXP
+ * Copyright 2016-2022 NXP
  */
 
 #ifndef __DPAA2_ETH_H
@@ -109,6 +109,14 @@
 #define DPAA2_ETH_RX_BUF_ALIGN_REV1	256
 #define DPAA2_ETH_RX_BUF_ALIGN		64
 
+/* The firmware allows assigning multiple buffer pools to a single DPNI -
+ * maximum 8 DPBP objects. By default, only the first DPBP (idx 0) is used for
+ * all queues. Thus, when enabling AF_XDP we must accommodate up to 9 DPBPs
+ * object: the default and 8 other distinct buffer pools, one for each queue.
+ */
+#define DPAA2_ETH_DEFAULT_BP_IDX	0
+#define DPAA2_ETH_MAX_BPS		9
+
 /* We are accommodating a skb backpointer and some S/G info
  * in the frame's software annotation. The hardware
  * options are either 0 or 64, so we choose the latter.
@@ -454,6 +462,11 @@ struct dpaa2_eth_ch_xdp {
 	unsigned int res;
 };
 
+struct dpaa2_eth_bp {
+	struct fsl_mc_device *dev;
+	int bpid;
+};
+
 struct dpaa2_eth_channel {
 	struct dpaa2_io_notification_ctx nctx;
 	struct fsl_mc_device *dpcon;
@@ -472,6 +485,8 @@ struct dpaa2_eth_channel {
 	/* Buffers to be recycled back in the buffer pool */
 	u64 recycled_bufs[DPAA2_ETH_BUFS_PER_CMD];
 	int recycled_bufs_cnt;
+
+	struct dpaa2_eth_bp *bp;
 };
 
 struct dpaa2_eth_dist_fields {
@@ -535,14 +550,16 @@ struct dpaa2_eth_priv {
 	u8 ptp_correction_off;
 	void (*dpaa2_set_onestep_params_cb)(struct dpaa2_eth_priv *priv,
 					    u32 offset, u8 udp);
-	struct fsl_mc_device *dpbp_dev;
 	u16 rx_buf_size;
-	u16 bpid;
 	struct iommu_domain *iommu_domain;
 
 	enum hwtstamp_tx_types tx_tstamp_type;	/* Tx timestamping type */
 	bool rx_tstamp;				/* Rx timestamping enabled */
 
+	/* Buffer pool management */
+	struct dpaa2_eth_bp *bp[DPAA2_ETH_MAX_BPS];
+	int num_bps;
+
 	u16 tx_qdid;
 	struct fsl_mc_io *mc_io;
 	/* Cores which have an affine DPIO/DPCON.
@@ -771,4 +788,7 @@ void dpaa2_eth_dl_traps_unregister(struct dpaa2_eth_priv *priv);
 
 struct dpaa2_eth_trap_item *dpaa2_eth_dl_get_trap(struct dpaa2_eth_priv *priv,
 						  struct dpaa2_fapr *fapr);
+
+struct dpaa2_eth_bp *dpaa2_eth_allocate_dpbp(struct dpaa2_eth_priv *priv);
+void dpaa2_eth_free_dpbp(struct dpaa2_eth_priv *priv, struct dpaa2_eth_bp *bp);
 #endif	/* __DPAA2_H */

drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c

@@ -241,9 +241,9 @@ static void dpaa2_eth_get_ethtool_stats(struct net_device *net_dev,
 	u32 bcnt_rx_total = 0, bcnt_tx_total = 0;
 	struct dpaa2_eth_ch_stats *ch_stats;
 	struct dpaa2_eth_drv_stats *extras;
+	u32 buf_cnt, buf_cnt_total = 0;
 	int j, k, err, num_cnt, i = 0;
 	u32 fcnt, bcnt;
-	u32 buf_cnt;
 
 	memset(data, 0,
 	       sizeof(u64) * (DPAA2_ETH_NUM_STATS + DPAA2_ETH_NUM_EXTRA_STATS));
@@ -305,12 +305,15 @@ static void dpaa2_eth_get_ethtool_stats(struct net_device *net_dev,
 	*(data + i++) = fcnt_tx_total;
 	*(data + i++) = bcnt_tx_total;
 
-	err = dpaa2_io_query_bp_count(NULL, priv->bpid, &buf_cnt);
+	for (j = 0; j < priv->num_bps; j++) {
+		err = dpaa2_io_query_bp_count(NULL, priv->bp[j]->bpid, &buf_cnt);
 		if (err) {
 			netdev_warn(net_dev, "Buffer count query error %d\n", err);
 			return;
 		}
-	*(data + i++) = buf_cnt;
+		buf_cnt_total += buf_cnt;
+	}
+	*(data + i++) = buf_cnt_total;
 
 	if (dpaa2_eth_has_mac(priv))
 		dpaa2_mac_get_ethtool_stats(priv->mac, data + i);