1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright Sunplus Technology Co., Ltd.
3  *       All rights reserved.
4  */
5 
6 #include <linux/platform_device.h>
7 #include <linux/etherdevice.h>
8 #include <linux/netdevice.h>
9 #include <linux/bitfield.h>
10 #include <linux/spinlock.h>
11 #include <linux/of_mdio.h>
12 
13 #include "spl2sw_register.h"
14 #include "spl2sw_define.h"
15 #include "spl2sw_int.h"
16 
17 int spl2sw_rx_poll(struct napi_struct *napi, int budget)
18 {
19 	struct spl2sw_common *comm = container_of(napi, struct spl2sw_common, rx_napi);
20 	struct spl2sw_mac_desc *desc, *h_desc;
21 	struct net_device_stats *stats;
22 	struct sk_buff *skb, *new_skb;
23 	struct spl2sw_skb_info *sinfo;
24 	int budget_left = budget;
25 	unsigned long flags;
26 	u32 rx_pos, pkg_len;
27 	u32 num, rx_count;
28 	s32 queue;
29 	u32 mask;
30 	int port;
31 	u32 cmd;
32 	u32 len;
33 
34 	/* Process high-priority queue and then low-priority queue. */
35 	for (queue = 0; queue < RX_DESC_QUEUE_NUM; queue++) {
36 		rx_pos = comm->rx_pos[queue];
37 		rx_count = comm->rx_desc_num[queue];
38 
39 		for (num = 0; num < rx_count && budget_left; num++) {
40 			sinfo = comm->rx_skb_info[queue] + rx_pos;
41 			desc = comm->rx_desc[queue] + rx_pos;
42 			cmd = desc->cmd1;
43 
44 			if (cmd & RXD_OWN)
45 				break;
46 
47 			port = FIELD_GET(RXD_PKT_SP, cmd);
48 			if (port < MAX_NETDEV_NUM && comm->ndev[port])
49 				stats = &comm->ndev[port]->stats;
50 			else
51 				goto spl2sw_rx_poll_rec_err;
52 
53 			pkg_len = FIELD_GET(RXD_PKT_LEN, cmd);
54 			if (unlikely((cmd & RXD_ERR_CODE) || pkg_len < ETH_ZLEN + 4)) {
55 				stats->rx_length_errors++;
56 				stats->rx_dropped++;
57 				goto spl2sw_rx_poll_rec_err;
58 			}
59 
60 			dma_unmap_single(&comm->pdev->dev, sinfo->mapping,
61 					 comm->rx_desc_buff_size, DMA_FROM_DEVICE);
62 
63 			skb = sinfo->skb;
64 			skb_put(skb, pkg_len - 4); /* Minus FCS */
65 			skb->ip_summed = CHECKSUM_NONE;
66 			skb->protocol = eth_type_trans(skb, comm->ndev[port]);
67 			len = skb->len;
68 			netif_receive_skb(skb);
69 
70 			stats->rx_packets++;
71 			stats->rx_bytes += len;
72 
73 			/* Allocate a new skb for receiving. */
74 			new_skb = netdev_alloc_skb(NULL, comm->rx_desc_buff_size);
75 			if (unlikely(!new_skb)) {
76 				desc->cmd2 = (rx_pos == comm->rx_desc_num[queue] - 1) ?
77 					     RXD_EOR : 0;
78 				sinfo->skb = NULL;
79 				sinfo->mapping = 0;
80 				desc->addr1 = 0;
81 				goto spl2sw_rx_poll_alloc_err;
82 			}
83 
84 			sinfo->mapping = dma_map_single(&comm->pdev->dev, new_skb->data,
85 							comm->rx_desc_buff_size,
86 							DMA_FROM_DEVICE);
87 			if (dma_mapping_error(&comm->pdev->dev, sinfo->mapping)) {
88 				dev_kfree_skb_irq(new_skb);
89 				desc->cmd2 = (rx_pos == comm->rx_desc_num[queue] - 1) ?
90 					     RXD_EOR : 0;
91 				sinfo->skb = NULL;
92 				sinfo->mapping = 0;
93 				desc->addr1 = 0;
94 				goto spl2sw_rx_poll_alloc_err;
95 			}
96 
97 			sinfo->skb = new_skb;
98 			desc->addr1 = sinfo->mapping;
99 
100 spl2sw_rx_poll_rec_err:
101 			desc->cmd2 = (rx_pos == comm->rx_desc_num[queue] - 1) ?
102 				     RXD_EOR | comm->rx_desc_buff_size :
103 				     comm->rx_desc_buff_size;
104 
105 			wmb();	/* Set RXD_OWN after other fields are effective. */
106 			desc->cmd1 = RXD_OWN;
107 
108 spl2sw_rx_poll_alloc_err:
109 			/* Move rx_pos to next position */
110 			rx_pos = ((rx_pos + 1) == comm->rx_desc_num[queue]) ? 0 : rx_pos + 1;
111 
112 			budget_left--;
113 
114 			/* If there are packets in high-priority queue,
115 			 * stop processing low-priority queue.
116 			 */
117 			if (queue == 1 && !(h_desc->cmd1 & RXD_OWN))
118 				break;
119 		}
120 
121 		comm->rx_pos[queue] = rx_pos;
122 
123 		/* Save pointer to last rx descriptor of high-priority queue. */
124 		if (queue == 0)
125 			h_desc = comm->rx_desc[queue] + rx_pos;
126 	}
127 
128 	spin_lock_irqsave(&comm->int_mask_lock, flags);
129 	mask = readl(comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
130 	mask &= ~MAC_INT_RX;
131 	writel(mask, comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
132 	spin_unlock_irqrestore(&comm->int_mask_lock, flags);
133 
134 	napi_complete(napi);
135 	return budget - budget_left;
136 }
137 
138 int spl2sw_tx_poll(struct napi_struct *napi, int budget)
139 {
140 	struct spl2sw_common *comm = container_of(napi, struct spl2sw_common, tx_napi);
141 	struct spl2sw_skb_info *skbinfo;
142 	struct net_device_stats *stats;
143 	int budget_left = budget;
144 	unsigned long flags;
145 	u32 tx_done_pos;
146 	u32 mask;
147 	u32 cmd;
148 	int i;
149 
150 	spin_lock(&comm->tx_lock);
151 
152 	tx_done_pos = comm->tx_done_pos;
153 	while (((tx_done_pos != comm->tx_pos) || (comm->tx_desc_full == 1)) && budget_left) {
154 		cmd = comm->tx_desc[tx_done_pos].cmd1;
155 		if (cmd & TXD_OWN)
156 			break;
157 
158 		skbinfo = &comm->tx_temp_skb_info[tx_done_pos];
159 		if (unlikely(!skbinfo->skb))
160 			goto spl2sw_tx_poll_next;
161 
162 		i = ffs(FIELD_GET(TXD_VLAN, cmd)) - 1;
163 		if (i < MAX_NETDEV_NUM && comm->ndev[i])
164 			stats = &comm->ndev[i]->stats;
165 		else
166 			goto spl2sw_tx_poll_unmap;
167 
168 		if (unlikely(cmd & (TXD_ERR_CODE))) {
169 			stats->tx_errors++;
170 		} else {
171 			stats->tx_packets++;
172 			stats->tx_bytes += skbinfo->len;
173 		}
174 
175 spl2sw_tx_poll_unmap:
176 		dma_unmap_single(&comm->pdev->dev, skbinfo->mapping, skbinfo->len,
177 				 DMA_TO_DEVICE);
178 		skbinfo->mapping = 0;
179 		dev_kfree_skb_irq(skbinfo->skb);
180 		skbinfo->skb = NULL;
181 
182 spl2sw_tx_poll_next:
183 		/* Move tx_done_pos to next position */
184 		tx_done_pos = ((tx_done_pos + 1) == TX_DESC_NUM) ? 0 : tx_done_pos + 1;
185 
186 		if (comm->tx_desc_full == 1)
187 			comm->tx_desc_full = 0;
188 
189 		budget_left--;
190 	}
191 
192 	comm->tx_done_pos = tx_done_pos;
193 	if (!comm->tx_desc_full)
194 		for (i = 0; i < MAX_NETDEV_NUM; i++)
195 			if (comm->ndev[i])
196 				if (netif_queue_stopped(comm->ndev[i]))
197 					netif_wake_queue(comm->ndev[i]);
198 
199 	spin_unlock(&comm->tx_lock);
200 
201 	spin_lock_irqsave(&comm->int_mask_lock, flags);
202 	mask = readl(comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
203 	mask &= ~MAC_INT_TX;
204 	writel(mask, comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
205 	spin_unlock_irqrestore(&comm->int_mask_lock, flags);
206 
207 	napi_complete(napi);
208 	return budget - budget_left;
209 }
210 
211 irqreturn_t spl2sw_ethernet_interrupt(int irq, void *dev_id)
212 {
213 	struct spl2sw_common *comm = (struct spl2sw_common *)dev_id;
214 	u32 status;
215 	u32 mask;
216 	int i;
217 
218 	status = readl(comm->l2sw_reg_base + L2SW_SW_INT_STATUS_0);
219 	if (unlikely(!status)) {
220 		dev_dbg(&comm->pdev->dev, "Interrupt status is null!\n");
221 		goto spl2sw_ethernet_int_out;
222 	}
223 	writel(status, comm->l2sw_reg_base + L2SW_SW_INT_STATUS_0);
224 
225 	if (status & MAC_INT_RX) {
226 		/* Disable RX interrupts. */
227 		spin_lock(&comm->int_mask_lock);
228 		mask = readl(comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
229 		mask |= MAC_INT_RX;
230 		writel(mask, comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
231 		spin_unlock(&comm->int_mask_lock);
232 
233 		if (unlikely(status & MAC_INT_RX_DES_ERR)) {
234 			for (i = 0; i < MAX_NETDEV_NUM; i++)
235 				if (comm->ndev[i]) {
236 					comm->ndev[i]->stats.rx_fifo_errors++;
237 					break;
238 				}
239 			dev_dbg(&comm->pdev->dev, "Illegal RX Descriptor!\n");
240 		}
241 
242 		napi_schedule(&comm->rx_napi);
243 	}
244 
245 	if (status & MAC_INT_TX) {
246 		/* Disable TX interrupts. */
247 		spin_lock(&comm->int_mask_lock);
248 		mask = readl(comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
249 		mask |= MAC_INT_TX;
250 		writel(mask, comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
251 		spin_unlock(&comm->int_mask_lock);
252 
253 		if (unlikely(status & MAC_INT_TX_DES_ERR)) {
254 			for (i = 0; i < MAX_NETDEV_NUM; i++)
255 				if (comm->ndev[i]) {
256 					comm->ndev[i]->stats.tx_fifo_errors++;
257 					break;
258 				}
259 			dev_dbg(&comm->pdev->dev, "Illegal TX Descriptor Error\n");
260 
261 			spin_lock(&comm->int_mask_lock);
262 			mask = readl(comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
263 			mask &= ~MAC_INT_TX;
264 			writel(mask, comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
265 			spin_unlock(&comm->int_mask_lock);
266 		} else {
267 			napi_schedule(&comm->tx_napi);
268 		}
269 	}
270 
271 spl2sw_ethernet_int_out:
272 	return IRQ_HANDLED;
273 }
274