1 /*
2 * IXP2000 MSF network device driver
3 * Copyright (C) 2004, 2005 Lennert Buytenhek <buytenh@wantstofly.org>
4 * Dedicated to Marija Kulikova.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/netdevice.h>
15 #include <linux/etherdevice.h>
16 #include <linux/init.h>
17 #include <linux/interrupt.h>
18 #include <linux/moduleparam.h>
19 #include <linux/gfp.h>
20 #include <asm/hardware/uengine.h>
21 #include <asm/io.h>
22 #include "ixp2400_rx.ucode"
23 #include "ixp2400_tx.ucode"
24 #include "ixpdev_priv.h"
25 #include "ixpdev.h"
26 #include "pm3386.h"
27
28 #define DRV_MODULE_VERSION "0.2"
29
30 static int nds_count;
31 static struct net_device **nds;
32 static int nds_open;
33 static void (*set_port_admin_status)(int port, int up);
34
35 static struct ixpdev_rx_desc * const rx_desc =
36 (struct ixpdev_rx_desc *)(IXP2000_SRAM0_VIRT_BASE + RX_BUF_DESC_BASE);
37 static struct ixpdev_tx_desc * const tx_desc =
38 (struct ixpdev_tx_desc *)(IXP2000_SRAM0_VIRT_BASE + TX_BUF_DESC_BASE);
39 static int tx_pointer;
40
41
ixpdev_xmit(struct sk_buff * skb,struct net_device * dev)42 static int ixpdev_xmit(struct sk_buff *skb, struct net_device *dev)
43 {
44 struct ixpdev_priv *ip = netdev_priv(dev);
45 struct ixpdev_tx_desc *desc;
46 int entry;
47 unsigned long flags;
48
49 if (unlikely(skb->len > PAGE_SIZE)) {
50 /* @@@ Count drops. */
51 dev_kfree_skb(skb);
52 return NETDEV_TX_OK;
53 }
54
55 entry = tx_pointer;
56 tx_pointer = (tx_pointer + 1) % TX_BUF_COUNT;
57
58 desc = tx_desc + entry;
59 desc->pkt_length = skb->len;
60 desc->channel = ip->channel;
61
62 skb_copy_and_csum_dev(skb, phys_to_virt(desc->buf_addr));
63 dev_kfree_skb(skb);
64
65 ixp2000_reg_write(RING_TX_PENDING,
66 TX_BUF_DESC_BASE + (entry * sizeof(struct ixpdev_tx_desc)));
67
68 local_irq_save(flags);
69 ip->tx_queue_entries++;
70 if (ip->tx_queue_entries == TX_BUF_COUNT_PER_CHAN)
71 netif_stop_queue(dev);
72 local_irq_restore(flags);
73
74 return NETDEV_TX_OK;
75 }
76
77
ixpdev_rx(struct net_device * dev,int processed,int budget)78 static int ixpdev_rx(struct net_device *dev, int processed, int budget)
79 {
80 while (processed < budget) {
81 struct ixpdev_rx_desc *desc;
82 struct sk_buff *skb;
83 void *buf;
84 u32 _desc;
85
86 _desc = ixp2000_reg_read(RING_RX_DONE);
87 if (_desc == 0)
88 return 0;
89
90 desc = rx_desc +
91 ((_desc - RX_BUF_DESC_BASE) / sizeof(struct ixpdev_rx_desc));
92 buf = phys_to_virt(desc->buf_addr);
93
94 if (desc->pkt_length < 4 || desc->pkt_length > PAGE_SIZE) {
95 printk(KERN_ERR "ixp2000: rx err, length %d\n",
96 desc->pkt_length);
97 goto err;
98 }
99
100 if (desc->channel < 0 || desc->channel >= nds_count) {
101 printk(KERN_ERR "ixp2000: rx err, channel %d\n",
102 desc->channel);
103 goto err;
104 }
105
106 /* @@@ Make FCS stripping configurable. */
107 desc->pkt_length -= 4;
108
109 if (unlikely(!netif_running(nds[desc->channel])))
110 goto err;
111
112 skb = netdev_alloc_skb_ip_align(dev, desc->pkt_length);
113 if (likely(skb != NULL)) {
114 skb_copy_to_linear_data(skb, buf, desc->pkt_length);
115 skb_put(skb, desc->pkt_length);
116 skb->protocol = eth_type_trans(skb, nds[desc->channel]);
117
118 netif_receive_skb(skb);
119 }
120
121 err:
122 ixp2000_reg_write(RING_RX_PENDING, _desc);
123 processed++;
124 }
125
126 return processed;
127 }
128
129 /* dev always points to nds[0]. */
ixpdev_poll(struct napi_struct * napi,int budget)130 static int ixpdev_poll(struct napi_struct *napi, int budget)
131 {
132 struct ixpdev_priv *ip = container_of(napi, struct ixpdev_priv, napi);
133 struct net_device *dev = ip->dev;
134 int rx;
135
136 rx = 0;
137 do {
138 ixp2000_reg_write(IXP2000_IRQ_THD_RAW_STATUS_A_0, 0x00ff);
139
140 rx = ixpdev_rx(dev, rx, budget);
141 if (rx >= budget)
142 break;
143 } while (ixp2000_reg_read(IXP2000_IRQ_THD_RAW_STATUS_A_0) & 0x00ff);
144
145 napi_complete(napi);
146 ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_SET_A_0, 0x00ff);
147
148 return rx;
149 }
150
ixpdev_tx_complete(void)151 static void ixpdev_tx_complete(void)
152 {
153 int channel;
154 u32 wake;
155
156 wake = 0;
157 while (1) {
158 struct ixpdev_priv *ip;
159 u32 desc;
160 int entry;
161
162 desc = ixp2000_reg_read(RING_TX_DONE);
163 if (desc == 0)
164 break;
165
166 /* @@@ Check whether entries come back in order. */
167 entry = (desc - TX_BUF_DESC_BASE) / sizeof(struct ixpdev_tx_desc);
168 channel = tx_desc[entry].channel;
169
170 if (channel < 0 || channel >= nds_count) {
171 printk(KERN_ERR "ixp2000: txcomp channel index "
172 "out of bounds (%d, %.8i, %d)\n",
173 channel, (unsigned int)desc, entry);
174 continue;
175 }
176
177 ip = netdev_priv(nds[channel]);
178 if (ip->tx_queue_entries == TX_BUF_COUNT_PER_CHAN)
179 wake |= 1 << channel;
180 ip->tx_queue_entries--;
181 }
182
183 for (channel = 0; wake != 0; channel++) {
184 if (wake & (1 << channel)) {
185 netif_wake_queue(nds[channel]);
186 wake &= ~(1 << channel);
187 }
188 }
189 }
190
ixpdev_interrupt(int irq,void * dev_id)191 static irqreturn_t ixpdev_interrupt(int irq, void *dev_id)
192 {
193 u32 status;
194
195 status = ixp2000_reg_read(IXP2000_IRQ_THD_STATUS_A_0);
196 if (status == 0)
197 return IRQ_NONE;
198
199 /*
200 * Any of the eight receive units signaled RX?
201 */
202 if (status & 0x00ff) {
203 struct net_device *dev = nds[0];
204 struct ixpdev_priv *ip = netdev_priv(dev);
205
206 ixp2000_reg_wrb(IXP2000_IRQ_THD_ENABLE_CLEAR_A_0, 0x00ff);
207 if (likely(napi_schedule_prep(&ip->napi))) {
208 __napi_schedule(&ip->napi);
209 } else {
210 printk(KERN_CRIT "ixp2000: irq while polling!!\n");
211 }
212 }
213
214 /*
215 * Any of the eight transmit units signaled TXdone?
216 */
217 if (status & 0xff00) {
218 ixp2000_reg_wrb(IXP2000_IRQ_THD_RAW_STATUS_A_0, 0xff00);
219 ixpdev_tx_complete();
220 }
221
222 return IRQ_HANDLED;
223 }
224
225 #ifdef CONFIG_NET_POLL_CONTROLLER
ixpdev_poll_controller(struct net_device * dev)226 static void ixpdev_poll_controller(struct net_device *dev)
227 {
228 disable_irq(IRQ_IXP2000_THDA0);
229 ixpdev_interrupt(IRQ_IXP2000_THDA0, dev);
230 enable_irq(IRQ_IXP2000_THDA0);
231 }
232 #endif
233
ixpdev_open(struct net_device * dev)234 static int ixpdev_open(struct net_device *dev)
235 {
236 struct ixpdev_priv *ip = netdev_priv(dev);
237 int err;
238
239 napi_enable(&ip->napi);
240 if (!nds_open++) {
241 err = request_irq(IRQ_IXP2000_THDA0, ixpdev_interrupt,
242 IRQF_SHARED, "ixp2000_eth", nds);
243 if (err) {
244 nds_open--;
245 napi_disable(&ip->napi);
246 return err;
247 }
248
249 ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_SET_A_0, 0xffff);
250 }
251
252 set_port_admin_status(ip->channel, 1);
253 netif_start_queue(dev);
254
255 return 0;
256 }
257
ixpdev_close(struct net_device * dev)258 static int ixpdev_close(struct net_device *dev)
259 {
260 struct ixpdev_priv *ip = netdev_priv(dev);
261
262 netif_stop_queue(dev);
263 napi_disable(&ip->napi);
264 set_port_admin_status(ip->channel, 0);
265
266 if (!--nds_open) {
267 ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_CLEAR_A_0, 0xffff);
268 free_irq(IRQ_IXP2000_THDA0, nds);
269 }
270
271 return 0;
272 }
273
ixpdev_get_stats(struct net_device * dev)274 static struct net_device_stats *ixpdev_get_stats(struct net_device *dev)
275 {
276 struct ixpdev_priv *ip = netdev_priv(dev);
277
278 pm3386_get_stats(ip->channel, &(dev->stats));
279
280 return &(dev->stats);
281 }
282
283 static const struct net_device_ops ixpdev_netdev_ops = {
284 .ndo_open = ixpdev_open,
285 .ndo_stop = ixpdev_close,
286 .ndo_start_xmit = ixpdev_xmit,
287 .ndo_change_mtu = eth_change_mtu,
288 .ndo_validate_addr = eth_validate_addr,
289 .ndo_set_mac_address = eth_mac_addr,
290 .ndo_get_stats = ixpdev_get_stats,
291 #ifdef CONFIG_NET_POLL_CONTROLLER
292 .ndo_poll_controller = ixpdev_poll_controller,
293 #endif
294 };
295
ixpdev_alloc(int channel,int sizeof_priv)296 struct net_device *ixpdev_alloc(int channel, int sizeof_priv)
297 {
298 struct net_device *dev;
299 struct ixpdev_priv *ip;
300
301 dev = alloc_etherdev(sizeof_priv);
302 if (dev == NULL)
303 return NULL;
304
305 dev->netdev_ops = &ixpdev_netdev_ops;
306
307 dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
308
309 ip = netdev_priv(dev);
310 ip->dev = dev;
311 netif_napi_add(dev, &ip->napi, ixpdev_poll, 64);
312 ip->channel = channel;
313 ip->tx_queue_entries = 0;
314
315 return dev;
316 }
317
ixpdev_init(int __nds_count,struct net_device ** __nds,void (* __set_port_admin_status)(int port,int up))318 int ixpdev_init(int __nds_count, struct net_device **__nds,
319 void (*__set_port_admin_status)(int port, int up))
320 {
321 int i;
322 int err;
323
324 BUILD_BUG_ON(RX_BUF_COUNT > 192 || TX_BUF_COUNT > 192);
325
326 printk(KERN_INFO "IXP2000 MSF ethernet driver %s\n", DRV_MODULE_VERSION);
327
328 nds_count = __nds_count;
329 nds = __nds;
330 set_port_admin_status = __set_port_admin_status;
331
332 for (i = 0; i < RX_BUF_COUNT; i++) {
333 void *buf;
334
335 buf = (void *)get_zeroed_page(GFP_KERNEL);
336 if (buf == NULL) {
337 err = -ENOMEM;
338 while (--i >= 0)
339 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
340 goto err_out;
341 }
342 rx_desc[i].buf_addr = virt_to_phys(buf);
343 rx_desc[i].buf_length = PAGE_SIZE;
344 }
345
346 /* @@@ Maybe we shouldn't be preallocating TX buffers. */
347 for (i = 0; i < TX_BUF_COUNT; i++) {
348 void *buf;
349
350 buf = (void *)get_zeroed_page(GFP_KERNEL);
351 if (buf == NULL) {
352 err = -ENOMEM;
353 while (--i >= 0)
354 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
355 goto err_free_rx;
356 }
357 tx_desc[i].buf_addr = virt_to_phys(buf);
358 }
359
360 /* 256 entries, ring status set means 'empty', base address 0x0000. */
361 ixp2000_reg_write(RING_RX_PENDING_BASE, 0x44000000);
362 ixp2000_reg_write(RING_RX_PENDING_HEAD, 0x00000000);
363 ixp2000_reg_write(RING_RX_PENDING_TAIL, 0x00000000);
364
365 /* 256 entries, ring status set means 'full', base address 0x0400. */
366 ixp2000_reg_write(RING_RX_DONE_BASE, 0x40000400);
367 ixp2000_reg_write(RING_RX_DONE_HEAD, 0x00000000);
368 ixp2000_reg_write(RING_RX_DONE_TAIL, 0x00000000);
369
370 for (i = 0; i < RX_BUF_COUNT; i++) {
371 ixp2000_reg_write(RING_RX_PENDING,
372 RX_BUF_DESC_BASE + (i * sizeof(struct ixpdev_rx_desc)));
373 }
374
375 ixp2000_uengine_load(0, &ixp2400_rx);
376 ixp2000_uengine_start_contexts(0, 0xff);
377
378 /* 256 entries, ring status set means 'empty', base address 0x0800. */
379 ixp2000_reg_write(RING_TX_PENDING_BASE, 0x44000800);
380 ixp2000_reg_write(RING_TX_PENDING_HEAD, 0x00000000);
381 ixp2000_reg_write(RING_TX_PENDING_TAIL, 0x00000000);
382
383 /* 256 entries, ring status set means 'full', base address 0x0c00. */
384 ixp2000_reg_write(RING_TX_DONE_BASE, 0x40000c00);
385 ixp2000_reg_write(RING_TX_DONE_HEAD, 0x00000000);
386 ixp2000_reg_write(RING_TX_DONE_TAIL, 0x00000000);
387
388 ixp2000_uengine_load(1, &ixp2400_tx);
389 ixp2000_uengine_start_contexts(1, 0xff);
390
391 for (i = 0; i < nds_count; i++) {
392 err = register_netdev(nds[i]);
393 if (err) {
394 while (--i >= 0)
395 unregister_netdev(nds[i]);
396 goto err_free_tx;
397 }
398 }
399
400 for (i = 0; i < nds_count; i++) {
401 printk(KERN_INFO "%s: IXP2000 MSF ethernet (port %d), %pM.\n",
402 nds[i]->name, i, nds[i]->dev_addr);
403 }
404
405 return 0;
406
407 err_free_tx:
408 for (i = 0; i < TX_BUF_COUNT; i++)
409 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
410
411 err_free_rx:
412 for (i = 0; i < RX_BUF_COUNT; i++)
413 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
414
415 err_out:
416 return err;
417 }
418
ixpdev_deinit(void)419 void ixpdev_deinit(void)
420 {
421 int i;
422
423 /* @@@ Flush out pending packets. */
424
425 for (i = 0; i < nds_count; i++)
426 unregister_netdev(nds[i]);
427
428 ixp2000_uengine_stop_contexts(1, 0xff);
429 ixp2000_uengine_stop_contexts(0, 0xff);
430 ixp2000_uengine_reset(0x3);
431
432 for (i = 0; i < TX_BUF_COUNT; i++)
433 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
434
435 for (i = 0; i < RX_BUF_COUNT; i++)
436 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
437 }
438