drivers: net: xgene: Change ring manager to use function pointers

This is a preparatory patch for adding ethernet support for APM X-Gene
ethernet driver to work with ring manager v2.

Added xgene_ring_ops structure for storing chip specific ring manager
properties and functions.

Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/apm/xgene/xgene_enet_hw.c

@@ -87,10 +87,11 @@ static void xgene_enet_ring_rd32(struct xgene_enet_desc_ring *ring,
 
 static void xgene_enet_write_ring_state(struct xgene_enet_desc_ring *ring)
 {
+	struct xgene_enet_pdata *pdata = netdev_priv(ring->ndev);
 	int i;
 
 	xgene_enet_ring_wr32(ring, CSR_RING_CONFIG, ring->num);
-	for (i = 0; i < NUM_RING_CONFIG; i++) {
+	for (i = 0; i < pdata->ring_ops->num_ring_config; i++) {
 		xgene_enet_ring_wr32(ring, CSR_RING_WR_BASE + (i * 4),
 				     ring->state[i]);
 	}
@@ -98,7 +99,7 @@ static void xgene_enet_write_ring_state(struct xgene_enet_desc_ring *ring)
 
 static void xgene_enet_clr_ring_state(struct xgene_enet_desc_ring *ring)
 {
-	memset(ring->state, 0, sizeof(u32) * NUM_RING_CONFIG);
+	memset(ring->state, 0, sizeof(ring->state));
 	xgene_enet_write_ring_state(ring);
 }
 
@@ -141,8 +142,8 @@ static void xgene_enet_clr_desc_ring_id(struct xgene_enet_desc_ring *ring)
 	xgene_enet_ring_wr32(ring, CSR_RING_ID_BUF, 0);
 }
 
-struct xgene_enet_desc_ring *xgene_enet_setup_ring(
-					struct xgene_enet_desc_ring *ring)
+static struct xgene_enet_desc_ring *xgene_enet_setup_ring(
+				    struct xgene_enet_desc_ring *ring)
 {
 	u32 size = ring->size;
 	u32 i, data;
@@ -168,7 +169,7 @@ struct xgene_enet_desc_ring *xgene_enet_setup_ring(
 	return ring;
 }
 
-void xgene_enet_clear_ring(struct xgene_enet_desc_ring *ring)
+static void xgene_enet_clear_ring(struct xgene_enet_desc_ring *ring)
 {
 	u32 data;
 	bool is_bufpool;
@@ -186,6 +187,22 @@ out:
 	xgene_enet_clr_ring_state(ring);
 }
 
+static void xgene_enet_wr_cmd(struct xgene_enet_desc_ring *ring, int count)
+{
+	iowrite32(count, ring->cmd);
+}
+
+static u32 xgene_enet_ring_len(struct xgene_enet_desc_ring *ring)
+{
+	u32 __iomem *cmd_base = ring->cmd_base;
+	u32 ring_state, num_msgs;
+
+	ring_state = ioread32(&cmd_base[1]);
+	num_msgs = GET_VAL(NUMMSGSINQ, ring_state);
+
+	return num_msgs;
+}
+
 void xgene_enet_parse_error(struct xgene_enet_desc_ring *ring,
 			    struct xgene_enet_pdata *pdata,
 			    enum xgene_enet_err_code status)
@@ -803,3 +820,12 @@ struct xgene_port_ops xgene_gport_ops = {
 	.cle_bypass = xgene_enet_cle_bypass,
 	.shutdown = xgene_gport_shutdown,
 };
+
+struct xgene_ring_ops xgene_ring1_ops = {
+	.num_ring_config = NUM_RING_CONFIG,
+	.num_ring_id_shift = 6,
+	.setup = xgene_enet_setup_ring,
+	.clear = xgene_enet_clear_ring,
+	.wr_cmd = xgene_enet_wr_cmd,
+	.len = xgene_enet_ring_len,
+};

drivers/net/ethernet/apm/xgene/xgene_enet_hw.h

@@ -26,6 +26,7 @@
 
 struct xgene_enet_pdata;
 struct xgene_enet_stats;
+struct xgene_enet_desc_ring;
 
 /* clears and then set bits */
 static inline void xgene_set_bits(u32 *dst, u32 val, u32 start, u32 len)
@@ -314,9 +315,6 @@ static inline u16 xgene_enet_get_numslots(u16 id, u32 size)
 		      size / WORK_DESC_SIZE;
 }
 
-struct xgene_enet_desc_ring *xgene_enet_setup_ring(
-		struct xgene_enet_desc_ring *ring);
-void xgene_enet_clear_ring(struct xgene_enet_desc_ring *ring);
 void xgene_enet_parse_error(struct xgene_enet_desc_ring *ring,
 			    struct xgene_enet_pdata *pdata,
 			    enum xgene_enet_err_code status);
@@ -327,5 +325,6 @@ bool xgene_ring_mgr_init(struct xgene_enet_pdata *p);
 
 extern struct xgene_mac_ops xgene_gmac_ops;
 extern struct xgene_port_ops xgene_gport_ops;
+extern struct xgene_ring_ops xgene_ring1_ops;
 
 #endif /* __XGENE_ENET_HW_H__ */

drivers/net/ethernet/apm/xgene/xgene_enet_main.c

@@ -48,6 +48,7 @@ static int xgene_enet_refill_bufpool(struct xgene_enet_desc_ring *buf_pool,
 {
 	struct sk_buff *skb;
 	struct xgene_enet_raw_desc16 *raw_desc;
+	struct xgene_enet_pdata *pdata;
 	struct net_device *ndev;
 	struct device *dev;
 	dma_addr_t dma_addr;
@@ -58,6 +59,7 @@ static int xgene_enet_refill_bufpool(struct xgene_enet_desc_ring *buf_pool,
 
 	ndev = buf_pool->ndev;
 	dev = ndev_to_dev(buf_pool->ndev);
+	pdata = netdev_priv(ndev);
 	bufdatalen = BUF_LEN_CODE_2K | (SKB_BUFFER_SIZE & GENMASK(11, 0));
 	len = XGENE_ENET_MAX_MTU;
 
@@ -82,7 +84,7 @@ static int xgene_enet_refill_bufpool(struct xgene_enet_desc_ring *buf_pool,
 		tail = (tail + 1) & slots;
 	}
 
-	iowrite32(nbuf, buf_pool->cmd);
+	pdata->ring_ops->wr_cmd(buf_pool, nbuf);
 	buf_pool->tail = tail;
 
 	return 0;
@@ -102,26 +104,16 @@ static u8 xgene_enet_hdr_len(const void *data)
 	return (eth->h_proto == htons(ETH_P_8021Q)) ? VLAN_ETH_HLEN : ETH_HLEN;
 }
 
-static u32 xgene_enet_ring_len(struct xgene_enet_desc_ring *ring)
-{
-	u32 __iomem *cmd_base = ring->cmd_base;
-	u32 ring_state, num_msgs;
-
-	ring_state = ioread32(&cmd_base[1]);
-	num_msgs = ring_state & CREATE_MASK(NUMMSGSINQ_POS, NUMMSGSINQ_LEN);
-
-	return num_msgs >> NUMMSGSINQ_POS;
-}
-
 static void xgene_enet_delete_bufpool(struct xgene_enet_desc_ring *buf_pool)
 {
+	struct xgene_enet_pdata *pdata = netdev_priv(buf_pool->ndev);
 	struct xgene_enet_raw_desc16 *raw_desc;
 	u32 slots = buf_pool->slots - 1;
 	u32 tail = buf_pool->tail;
 	u32 userinfo;
 	int i, len;
 
-	len = xgene_enet_ring_len(buf_pool);
+	len = pdata->ring_ops->len(buf_pool);
 	for (i = 0; i < len; i++) {
 		tail = (tail - 1) & slots;
 		raw_desc = &buf_pool->raw_desc16[tail];
@@ -131,7 +123,7 @@ static void xgene_enet_delete_bufpool(struct xgene_enet_desc_ring *buf_pool)
 		dev_kfree_skb_any(buf_pool->rx_skb[userinfo]);
 	}
 
-	iowrite32(-len, buf_pool->cmd);
+	pdata->ring_ops->wr_cmd(buf_pool, -len);
 	buf_pool->tail = tail;
 }
 
@@ -263,8 +255,8 @@ static netdev_tx_t xgene_enet_start_xmit(struct sk_buff *skb,
 	struct xgene_enet_desc_ring *cp_ring = tx_ring->cp_ring;
 	u32 tx_level, cq_level;
 
-	tx_level = xgene_enet_ring_len(tx_ring);
-	cq_level = xgene_enet_ring_len(cp_ring);
+	tx_level = pdata->ring_ops->len(tx_ring);
+	cq_level = pdata->ring_ops->len(cp_ring);
 	if (unlikely(tx_level > pdata->tx_qcnt_hi ||
 		     cq_level > pdata->cp_qcnt_hi)) {
 		netif_stop_queue(ndev);
@@ -276,7 +268,7 @@ static netdev_tx_t xgene_enet_start_xmit(struct sk_buff *skb,
 		return NETDEV_TX_OK;
 	}
 
-	iowrite32(1, tx_ring->cmd);
+	pdata->ring_ops->wr_cmd(tx_ring, 1);
 	skb_tx_timestamp(skb);
 	tx_ring->tail = (tx_ring->tail + 1) & (tx_ring->slots - 1);
 
@@ -389,11 +381,11 @@ static int xgene_enet_process_ring(struct xgene_enet_desc_ring *ring,
 	} while (--budget);
 
 	if (likely(count)) {
-		iowrite32(-count, ring->cmd);
+		pdata->ring_ops->wr_cmd(ring, -count);
 		ring->head = head;
 
 		if (netif_queue_stopped(ring->ndev)) {
-			if (xgene_enet_ring_len(ring) < pdata->cp_qcnt_low)
+			if (pdata->ring_ops->len(ring) < pdata->cp_qcnt_low)
 				netif_wake_queue(ring->ndev);
 		}
 	}
@@ -510,6 +502,7 @@ static int xgene_enet_open(struct net_device *ndev)
 	else
 		schedule_delayed_work(&pdata->link_work, PHY_POLL_LINK_OFF);
 
+	netif_carrier_off(ndev);
 	netif_start_queue(ndev);
 
 	return ret;
@@ -545,7 +538,7 @@ static void xgene_enet_delete_ring(struct xgene_enet_desc_ring *ring)
 	pdata = netdev_priv(ring->ndev);
 	dev = ndev_to_dev(ring->ndev);
 
-	xgene_enet_clear_ring(ring);
+	pdata->ring_ops->clear(ring);
 	dma_free_coherent(dev, ring->size, ring->desc_addr, ring->dma);
 }
 
@@ -598,15 +591,17 @@ static int xgene_enet_get_ring_size(struct device *dev,
 
 static void xgene_enet_free_desc_ring(struct xgene_enet_desc_ring *ring)
 {
+	struct xgene_enet_pdata *pdata;
 	struct device *dev;
 
 	if (!ring)
 		return;
 
 	dev = ndev_to_dev(ring->ndev);
+	pdata = netdev_priv(ring->ndev);
 
 	if (ring->desc_addr) {
-		xgene_enet_clear_ring(ring);
+		pdata->ring_ops->clear(ring);
 		dma_free_coherent(dev, ring->size, ring->desc_addr, ring->dma);
 	}
 	devm_kfree(dev, ring);
@@ -670,7 +665,7 @@ static struct xgene_enet_desc_ring *xgene_enet_create_desc_ring(
 
 	ring->cmd_base = pdata->ring_cmd_addr + (ring->num << 6);
 	ring->cmd = ring->cmd_base + INC_DEC_CMD_ADDR;
-	ring = xgene_enet_setup_ring(ring);
+	ring = pdata->ring_ops->setup(ring);
 	netdev_dbg(ndev, "ring info: num=%d  size=%d  id=%d  slots=%d\n",
 		   ring->num, ring->size, ring->id, ring->slots);
 
@@ -1051,6 +1046,7 @@ static void xgene_enet_setup_ops(struct xgene_enet_pdata *pdata)
 		break;
 	}
 
+	pdata->ring_ops = &xgene_ring1_ops;
 }
 
 static void xgene_enet_napi_add(struct xgene_enet_pdata *pdata)

drivers/net/ethernet/apm/xgene/xgene_enet_main.h

@@ -105,6 +105,15 @@ struct xgene_port_ops {
 	void (*shutdown)(struct xgene_enet_pdata *pdata);
 };
 
+struct xgene_ring_ops {
+	u8 num_ring_config;
+	u8 num_ring_id_shift;
+	struct xgene_enet_desc_ring * (*setup)(struct xgene_enet_desc_ring *);
+	void (*clear)(struct xgene_enet_desc_ring *);
+	void (*wr_cmd)(struct xgene_enet_desc_ring *, int);
+	u32 (*len)(struct xgene_enet_desc_ring *);
+};
+
 /* ethernet private data */
 struct xgene_enet_pdata {
 	struct net_device *ndev;
@@ -136,6 +145,7 @@ struct xgene_enet_pdata {
 	struct rtnl_link_stats64 stats;
 	struct xgene_mac_ops *mac_ops;
 	struct xgene_port_ops *port_ops;
+	struct xgene_ring_ops *ring_ops;
 	struct delayed_work link_work;
 	u32 port_id;
 	u8 cpu_bufnum;