fixes dma bug in eth driver, that was caused under high net load. the dma ring was...
[lede.git] / target / linux / ramips / files / drivers / net / ramips.c
1 /*
2  *   This program is free software; you can redistribute it and/or modify
3  *   it under the terms of the GNU General Public License as published by
4  *   the Free Software Foundation; either version 2 of the License, or
5  *   (at your option) any later version.
6  *
7  *   This program is distributed in the hope that it will be useful,
8  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
9  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  *   GNU General Public License for more details.
11  *
12  *   You should have received a copy of the GNU General Public License
13  *   along with this program; if not, write to the Free Software
14  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
15  *
16  *   Copyright (C) 2009 John Crispin <blogic@openwrt.org>
17  */
18
19 #include <linux/module.h>
20 #include <linux/version.h>
21 #include <linux/kernel.h>
22 #include <linux/types.h>
23 #include <linux/pci.h>
24 #include <linux/init.h>
25 #include <linux/skbuff.h>
26 #include <linux/if_vlan.h>
27 #include <linux/if_ether.h>
28 #include <linux/platform_device.h>
29 #include <asm/uaccess.h>
30 #include <net/sock.h>
31 #include <asm/uaccess.h>
32
33 #include <eth.h>
34
35 #define TX_TIMEOUT (20 * HZ / 100)
36 #define MAX_RX_LENGTH   1500
37
38 #ifdef CONFIG_RALINK_RT305X
39 #include "ramips_esw.c"
40 #endif
41
42 static struct net_device * ramips_dev;
43 static void __iomem *ramips_fe_base = 0;
44
45 static inline void
46 ramips_fe_wr(u32 val, unsigned reg)
47 {
48         __raw_writel(val, ramips_fe_base + reg);
49 }
50
51 static inline u32
52 ramips_fe_rr(unsigned reg)
53 {
54         return __raw_readl(ramips_fe_base + reg);
55 }
56
57 static int
58 ramips_alloc_dma(struct net_device *dev)
59 {
60 #define phys_to_bus(a)  (a & 0x1FFFFFFF)
61         struct raeth_priv *priv = netdev_priv(dev);
62         int i;
63
64         priv->skb_free_idx = 0;
65
66         /* setup tx ring */
67         priv->tx = pci_alloc_consistent(NULL,
68                 NUM_TX_DESC * sizeof(struct ramips_tx_dma), &priv->phy_tx);
69         for(i = 0; i < NUM_TX_DESC; i++)
70         {
71                 memset(&priv->tx[i], 0, sizeof(struct ramips_tx_dma));
72                 priv->tx[i].txd2 |= TX_DMA_LSO | TX_DMA_DONE;
73                 priv->tx[i].txd4 &= (TX_DMA_QN_MASK | TX_DMA_PN_MASK);
74                 priv->tx[i].txd4 |= TX_DMA_QN(3) | TX_DMA_PN(1);
75         }
76         ramips_fe_wr(phys_to_bus(priv->phy_tx), RAMIPS_TX_BASE_PTR0);
77         ramips_fe_wr(NUM_TX_DESC, RAMIPS_TX_MAX_CNT0);
78         ramips_fe_wr(0, RAMIPS_TX_CTX_IDX0);
79         ramips_fe_wr(RAMIPS_PST_DTX_IDX0, RAMIPS_PDMA_RST_CFG);
80
81         /* setup rx ring */
82         priv->rx = pci_alloc_consistent(NULL,
83                 NUM_RX_DESC * sizeof(struct ramips_rx_dma), &priv->phy_rx);
84         memset(priv->rx, 0, sizeof(struct ramips_rx_dma) * NUM_RX_DESC);
85         for(i = 0; i < NUM_RX_DESC; i++)
86         {
87                 struct sk_buff *new_skb = dev_alloc_skb(MAX_RX_LENGTH + 2);
88                 BUG_ON(!new_skb);
89                 skb_reserve(new_skb, 2);
90                 priv->rx[i].rxd1 =
91                         dma_map_single(NULL, skb_put(new_skb, 2), MAX_RX_LENGTH + 2,
92                                 PCI_DMA_FROMDEVICE);
93                 priv->rx[i].rxd2 |= RX_DMA_LSO;
94                 priv->rx_skb[i] = new_skb;
95         }
96         dma_cache_wback_inv((unsigned long)priv->rx,
97                 NUM_RX_DESC * (sizeof(struct ramips_rx_dma)));
98
99         ramips_fe_wr(phys_to_bus(priv->phy_rx), RAMIPS_RX_BASE_PTR0);
100         ramips_fe_wr(NUM_RX_DESC, RAMIPS_RX_MAX_CNT0);
101         ramips_fe_wr((NUM_RX_DESC - 1), RAMIPS_RX_CALC_IDX0);
102         ramips_fe_wr(RAMIPS_PST_DRX_IDX0, RAMIPS_PDMA_RST_CFG);
103
104         return 0;
105 }
106
107 static int
108 ramips_eth_hard_start_xmit(struct sk_buff* skb, struct net_device *dev)
109 {
110         struct raeth_priv *priv = netdev_priv(dev);
111         unsigned long tx;
112         unsigned int tx_next;
113
114         if(priv->plat->min_pkt_len)
115         {
116                 if(skb->len < priv->plat->min_pkt_len)
117                  {
118                      if(skb_padto(skb, priv->plat->min_pkt_len))
119                          {
120                                  printk(KERN_ERR "ramips_eth: skb_padto failed\n");
121                                  kfree_skb(skb);
122                                  return 0;
123                          }
124                      skb_put(skb, priv->plat->min_pkt_len - skb->len);
125                  }
126         }
127         dev->trans_start = jiffies;
128         dma_cache_wback_inv((unsigned long)skb->data, skb->len);
129         tx = ramips_fe_rr(RAMIPS_TX_CTX_IDX0);
130         if(tx == NUM_TX_DESC - 1)
131                 tx_next = 0;
132         else
133                 tx_next = tx + 1;
134         if((priv->tx_skb[tx]== 0) && (priv->tx_skb[tx_next] == 0))
135         {
136                 if(!(priv->tx[tx].txd2 & TX_DMA_DONE))
137                 {
138                         kfree_skb(skb);
139                         dev->stats.tx_dropped++;
140                         printk(KERN_ERR "%s: dropping\n", dev->name);
141                         return 0;
142                 }
143                 priv->tx[tx].txd1 = virt_to_phys(skb->data);
144                 priv->tx[tx].txd2 &= ~(TX_DMA_PLEN0_MASK | TX_DMA_DONE);
145                 priv->tx[tx].txd2 |= TX_DMA_PLEN0(skb->len);
146                 ramips_fe_wr((tx + 1) % NUM_TX_DESC, RAMIPS_TX_CTX_IDX0);
147                 dev->stats.tx_packets++;
148                 dev->stats.tx_bytes += skb->len;
149                 priv->tx_skb[tx] = skb;
150                 ramips_fe_wr((tx + 1) % NUM_TX_DESC, RAMIPS_TX_CTX_IDX0);
151         } else {
152                 dev->stats.tx_dropped++;
153                 kfree_skb(skb);
154         }
155         return 0;
156 }
157
158 static void
159 ramips_eth_rx_hw(unsigned long ptr)
160 {
161         struct net_device *dev = (struct net_device*)ptr;
162         struct raeth_priv *priv = netdev_priv(dev);
163         int rx;
164         int max_rx = 16;
165
166         while(max_rx)
167         {
168                 struct sk_buff *rx_skb, *new_skb;
169
170                 rx = (ramips_fe_rr(RAMIPS_RX_CALC_IDX0) + 1) % NUM_RX_DESC;
171                 if(!(priv->rx[rx].rxd2 & RX_DMA_DONE))
172                         break;
173                 max_rx--;
174
175                 rx_skb = priv->rx_skb[rx];
176                 rx_skb->len = RX_DMA_PLEN0(priv->rx[rx].rxd2);
177                 rx_skb->tail = rx_skb->data + rx_skb->len;
178                 rx_skb->dev = dev;
179                 rx_skb->protocol = eth_type_trans(rx_skb, dev);
180                 rx_skb->ip_summed = CHECKSUM_NONE;
181                 dev->stats.rx_packets++;
182                 dev->stats.rx_bytes += rx_skb->len;
183                 netif_rx(rx_skb);
184
185                 new_skb = __dev_alloc_skb(MAX_RX_LENGTH + 2, GFP_DMA | GFP_ATOMIC);
186                 priv->rx_skb[rx] = new_skb;
187                 BUG_ON(!new_skb);
188                 skb_reserve(new_skb, 2);
189                 priv->rx[rx].rxd1 =
190                         dma_map_single(NULL, new_skb->data, MAX_RX_LENGTH + 2,
191                         PCI_DMA_FROMDEVICE);
192                 priv->rx[rx].rxd2 &= ~RX_DMA_DONE;
193                 dma_cache_wback_inv((unsigned long)&priv->rx[rx],
194                         sizeof(struct ramips_rx_dma));
195                 ramips_fe_wr(rx, RAMIPS_RX_CALC_IDX0);
196         }
197         if(max_rx == 0)
198                 tasklet_schedule(&priv->rx_tasklet);
199         else
200                 ramips_fe_wr(ramips_fe_rr(RAMIPS_FE_INT_ENABLE) | RAMIPS_RX_DLY_INT,
201                         RAMIPS_FE_INT_ENABLE);
202 }
203
204 static void
205 ramips_eth_tx_housekeeping(unsigned long ptr)
206 {
207         struct net_device *dev = (struct net_device*)ptr;
208         struct raeth_priv *priv = netdev_priv(dev);
209
210         while((priv->tx[priv->skb_free_idx].txd2 & TX_DMA_DONE) &&
211                 (priv->tx_skb[priv->skb_free_idx]))
212         {
213                 dev_kfree_skb_irq((struct sk_buff*)priv->tx_skb[priv->skb_free_idx]);
214                 priv->tx_skb[priv->skb_free_idx] = 0;
215                 priv->skb_free_idx++;
216                 if(priv->skb_free_idx >= NUM_TX_DESC)
217                         priv->skb_free_idx = 0;
218         }
219         ramips_fe_wr(ramips_fe_rr(RAMIPS_FE_INT_ENABLE) | RAMIPS_TX_DLY_INT,
220                 RAMIPS_FE_INT_ENABLE);
221 }
222
223 static int
224 ramips_eth_set_mac_addr(struct net_device *dev, void *priv)
225 {
226         unsigned char *mac = (unsigned char*)priv;
227
228         if(netif_running(dev))
229                 return -EBUSY;
230         memcpy(dev->dev_addr, ((struct sockaddr*)priv)->sa_data, dev->addr_len);
231         ramips_fe_wr((mac[0] << 8) | mac[1], RAMIPS_GDMA1_MAC_ADRH);
232         ramips_fe_wr(RAMIPS_GDMA1_MAC_ADRL,
233                 (mac[2] << 24) | (mac[3] << 16) | (mac[4] << 8) | mac[5]);
234         return 0;
235 }
236
237 static void
238 ramips_eth_timeout(struct net_device *dev)
239 {
240         struct raeth_priv *priv = netdev_priv(dev);
241
242         tasklet_schedule(&priv->tx_housekeeping_tasklet);
243 }
244
245 static irqreturn_t
246 ramips_eth_irq(int irq, void *dev)
247 {
248         struct raeth_priv *priv = netdev_priv(dev);
249         unsigned long fe_int = ramips_fe_rr(RAMIPS_FE_INT_STATUS);
250
251         ramips_fe_wr(0xFFFFFFFF, RAMIPS_FE_INT_STATUS);
252
253         if(fe_int & RAMIPS_RX_DLY_INT)
254         {
255                 ramips_fe_wr(ramips_fe_rr(RAMIPS_FE_INT_ENABLE) & ~(RAMIPS_RX_DLY_INT),
256                         RAMIPS_FE_INT_ENABLE);
257                 tasklet_schedule(&priv->rx_tasklet);
258         }
259         if(fe_int & RAMIPS_TX_DLY_INT)
260                 ramips_eth_tx_housekeeping((unsigned long)dev);
261         return IRQ_HANDLED;
262 }
263
264 static int
265 ramips_eth_open(struct net_device *dev)
266 {
267         struct raeth_priv *priv = netdev_priv(dev);
268
269         ramips_alloc_dma(dev);
270         ramips_fe_wr((ramips_fe_rr(RAMIPS_PDMA_GLO_CFG) & 0xff) |
271                 (RAMIPS_TX_WB_DDONE | RAMIPS_RX_DMA_EN |
272                 RAMIPS_TX_DMA_EN | RAMIPS_PDMA_SIZE_4DWORDS),
273                 RAMIPS_PDMA_GLO_CFG);
274         ramips_fe_wr((ramips_fe_rr(RAMIPS_FE_GLO_CFG) &
275                 ~(RAMIPS_US_CYC_CNT_MASK << RAMIPS_US_CYC_CNT_SHIFT)) |
276                 ((rt305x_sys_freq / RAMIPS_US_CYC_CNT_DIVISOR) << RAMIPS_US_CYC_CNT_SHIFT),
277                 RAMIPS_FE_GLO_CFG);
278         request_irq(dev->irq, ramips_eth_irq, IRQF_DISABLED, dev->name, dev);
279         tasklet_init(&priv->tx_housekeeping_tasklet, ramips_eth_tx_housekeeping,
280                 (unsigned long)dev);
281         tasklet_init(&priv->rx_tasklet, ramips_eth_rx_hw, (unsigned long)dev);
282         ramips_fe_wr(RAMIPS_DELAY_INIT, RAMIPS_DLY_INT_CFG);
283         ramips_fe_wr(RAMIPS_TX_DLY_INT | RAMIPS_RX_DLY_INT, RAMIPS_FE_INT_ENABLE);
284         ramips_fe_wr(ramips_fe_rr(RAMIPS_GDMA1_FWD_CFG) &
285                 ~(RAMIPS_GDM1_ICS_EN | RAMIPS_GDM1_TCS_EN | RAMIPS_GDM1_UCS_EN | 0xffff),
286                 RAMIPS_GDMA1_FWD_CFG);
287         ramips_fe_wr(ramips_fe_rr(RAMIPS_CDMA_CSG_CFG) &
288                 ~(RAMIPS_ICS_GEN_EN | RAMIPS_TCS_GEN_EN | RAMIPS_UCS_GEN_EN),
289                 RAMIPS_CDMA_CSG_CFG);
290         ramips_fe_wr(RAMIPS_PSE_FQFC_CFG_INIT, RAMIPS_PSE_FQ_CFG);
291         ramips_fe_wr(1, RAMIPS_FE_RST_GL);
292         ramips_fe_wr(0, RAMIPS_FE_RST_GL);
293         netif_start_queue(dev);
294         return 0;
295 }
296
297 static int
298 ramips_eth_stop(struct net_device *dev)
299 {
300         struct raeth_priv *priv = netdev_priv(dev);
301
302         ramips_fe_wr(RAMIPS_PDMA_GLO_CFG, ramips_fe_rr(RAMIPS_PDMA_GLO_CFG) &
303                 ~(RAMIPS_TX_WB_DDONE | RAMIPS_RX_DMA_EN | RAMIPS_TX_DMA_EN));
304         free_irq(dev->irq, dev);
305         netif_stop_queue(dev);
306         tasklet_kill(&priv->tx_housekeeping_tasklet);
307         tasklet_kill(&priv->rx_tasklet);
308         pci_free_consistent(NULL, NUM_TX_DESC * sizeof(struct ramips_tx_dma),
309                 priv->tx, priv->phy_tx);
310         pci_free_consistent(NULL, NUM_RX_DESC * sizeof(struct ramips_rx_dma),
311                 priv->rx, priv->phy_rx);
312         printk(KERN_DEBUG "ramips_eth: stopped\n");
313         return 0;
314 }
315
316 static int __init
317 ramips_eth_probe(struct net_device *dev)
318 {
319         struct raeth_priv *priv = netdev_priv(dev);
320         struct sockaddr addr;
321
322         BUG_ON(!priv->plat->reset_fe);
323         priv->plat->reset_fe();
324         net_srandom(jiffies);
325         memcpy(addr.sa_data, priv->plat->mac, 6);
326         ramips_eth_set_mac_addr(dev, &addr);
327
328         ether_setup(dev);
329         dev->open = ramips_eth_open;
330         dev->stop = ramips_eth_stop;
331         dev->hard_start_xmit = ramips_eth_hard_start_xmit;
332         dev->set_mac_address = ramips_eth_set_mac_addr;
333         dev->mtu = MAX_RX_LENGTH;
334         dev->tx_timeout = ramips_eth_timeout;
335         dev->watchdog_timeo = TX_TIMEOUT;
336         return 0;
337 }
338
339 static int
340 ramips_eth_plat_probe(struct platform_device *plat)
341 {
342         struct raeth_priv *priv;
343         struct ramips_eth_platform_data *data = plat->dev.platform_data;
344         ramips_fe_base = ioremap_nocache(data->base_addr, PAGE_SIZE);
345         if(!ramips_fe_base)
346                 return -ENOMEM;
347         ramips_dev = alloc_etherdev(sizeof(struct raeth_priv));
348         if(!ramips_dev)
349                 return -ENOMEM;
350         strcpy(ramips_dev->name, "eth%d");
351         ramips_dev->irq = data->irq;
352         ramips_dev->addr_len = ETH_ALEN;
353         ramips_dev->base_addr = (unsigned long)ramips_fe_base;
354         ramips_dev->init = ramips_eth_probe;
355         priv = (struct raeth_priv*)netdev_priv(ramips_dev);
356         priv->plat = data;
357         if(register_netdev(ramips_dev))
358         {
359                 printk(KERN_ERR "ramips_eth: error bringing up device\n");
360                 return -ENXIO;
361         }
362 #ifdef CONFIG_RALINK_RT305X
363         rt305x_esw_init();
364 #endif
365         printk(KERN_DEBUG "ramips_eth: loaded\n");
366         return 0;
367 }
368
369 static int
370 ramips_eth_plat_remove(struct platform_device *plat)
371 {
372         unregister_netdev(ramips_dev);
373         free_netdev(ramips_dev);
374         printk(KERN_DEBUG "ramips_eth: unloaded\n");
375         return 0;
376 }
377
378 static struct platform_driver ramips_eth_driver = {
379         .probe = ramips_eth_plat_probe,
380         .remove = ramips_eth_plat_remove,
381         .driver = {
382                 .name = "ramips_eth",
383                 .owner = THIS_MODULE,
384         },
385 };
386
387 static int __init
388 ramips_eth_init(void)
389 {
390         int ret = platform_driver_register(&ramips_eth_driver);
391         if (ret)
392                 printk(KERN_ERR
393                        "ramips_eth: Error registering platfom driver!\n");
394         return ret;
395 }
396
397 static void __exit
398 ramips_eth_cleanup(void)
399 {
400         platform_driver_unregister(&ramips_eth_driver);
401 }
402
403 module_init(ramips_eth_init);
404 module_exit(ramips_eth_cleanup);
405
406 MODULE_LICENSE("GPL");
407 MODULE_AUTHOR("John Crispin <blogic@openwrt.org>");
408 MODULE_DESCRIPTION("ethernet driver for ramips boards");