Merge master.kernel.org:/home/rmk/linux-2.6-serial
[linux-2.6] / drivers / net / ixp2000 / ixpdev.c
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/config.h>
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/netdevice.h>
16 #include <linux/etherdevice.h>
17 #include <linux/init.h>
18 #include <linux/moduleparam.h>
19 #include <asm/arch/uengine.h>
20 #include <asm/mach-types.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
27 #define DRV_MODULE_VERSION      "0.2"
28
29 static int nds_count;
30 static struct net_device **nds;
31 static int nds_open;
32 static void (*set_port_admin_status)(int port, int up);
33
34 static struct ixpdev_rx_desc * const rx_desc =
35         (struct ixpdev_rx_desc *)(IXP2000_SRAM0_VIRT_BASE + RX_BUF_DESC_BASE);
36 static struct ixpdev_tx_desc * const tx_desc =
37         (struct ixpdev_tx_desc *)(IXP2000_SRAM0_VIRT_BASE + TX_BUF_DESC_BASE);
38 static int tx_pointer;
39
40
41 static int ixpdev_xmit(struct sk_buff *skb, struct net_device *dev)
42 {
43         struct ixpdev_priv *ip = netdev_priv(dev);
44         struct ixpdev_tx_desc *desc;
45         int entry;
46
47         if (unlikely(skb->len > PAGE_SIZE)) {
48                 /* @@@ Count drops.  */
49                 dev_kfree_skb(skb);
50                 return 0;
51         }
52
53         entry = tx_pointer;
54         tx_pointer = (tx_pointer + 1) % TX_BUF_COUNT;
55
56         desc = tx_desc + entry;
57         desc->pkt_length = skb->len;
58         desc->channel = ip->channel;
59
60         skb_copy_and_csum_dev(skb, phys_to_virt(desc->buf_addr));
61         dev_kfree_skb(skb);
62
63         ixp2000_reg_write(RING_TX_PENDING,
64                 TX_BUF_DESC_BASE + (entry * sizeof(struct ixpdev_tx_desc)));
65
66         dev->trans_start = jiffies;
67
68         local_irq_disable();
69         ip->tx_queue_entries++;
70         if (ip->tx_queue_entries == TX_BUF_COUNT_PER_CHAN)
71                 netif_stop_queue(dev);
72         local_irq_enable();
73
74         return 0;
75 }
76
77
78 static int ixpdev_rx(struct net_device *dev, int *budget)
79 {
80         while (*budget > 0) {
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 = dev_alloc_skb(desc->pkt_length + 2);
113                 if (likely(skb != NULL)) {
114                         skb->dev = nds[desc->channel];
115                         skb_reserve(skb, 2);
116                         eth_copy_and_sum(skb, buf, desc->pkt_length, 0);
117                         skb_put(skb, desc->pkt_length);
118                         skb->protocol = eth_type_trans(skb, skb->dev);
119
120                         skb->dev->last_rx = jiffies;
121
122                         netif_receive_skb(skb);
123                 }
124
125 err:
126                 ixp2000_reg_write(RING_RX_PENDING, _desc);
127                 dev->quota--;
128                 (*budget)--;
129         }
130
131         return 1;
132 }
133
134 /* dev always points to nds[0].  */
135 static int ixpdev_poll(struct net_device *dev, int *budget)
136 {
137         /* @@@ Have to stop polling when nds[0] is administratively
138          * downed while we are polling.  */
139         do {
140                 ixp2000_reg_write(IXP2000_IRQ_THD_RAW_STATUS_A_0, 0x00ff);
141
142                 if (ixpdev_rx(dev, budget))
143                         return 1;
144         } while (ixp2000_reg_read(IXP2000_IRQ_THD_RAW_STATUS_A_0) & 0x00ff);
145
146         netif_rx_complete(dev);
147         ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_SET_A_0, 0x00ff);
148
149         return 0;
150 }
151
152 static void ixpdev_tx_complete(void)
153 {
154         int channel;
155         u32 wake;
156
157         wake = 0;
158         while (1) {
159                 struct ixpdev_priv *ip;
160                 u32 desc;
161                 int entry;
162
163                 desc = ixp2000_reg_read(RING_TX_DONE);
164                 if (desc == 0)
165                         break;
166
167                 /* @@@ Check whether entries come back in order.  */
168                 entry = (desc - TX_BUF_DESC_BASE) / sizeof(struct ixpdev_tx_desc);
169                 channel = tx_desc[entry].channel;
170
171                 if (channel < 0 || channel >= nds_count) {
172                         printk(KERN_ERR "ixp2000: txcomp channel index "
173                                         "out of bounds (%d, %.8i, %d)\n",
174                                         channel, (unsigned int)desc, entry);
175                         continue;
176                 }
177
178                 ip = netdev_priv(nds[channel]);
179                 if (ip->tx_queue_entries == TX_BUF_COUNT_PER_CHAN)
180                         wake |= 1 << channel;
181                 ip->tx_queue_entries--;
182         }
183
184         for (channel = 0; wake != 0; channel++) {
185                 if (wake & (1 << channel)) {
186                         netif_wake_queue(nds[channel]);
187                         wake &= ~(1 << channel);
188                 }
189         }
190 }
191
192 static irqreturn_t ixpdev_interrupt(int irq, void *dev_id, struct pt_regs *regs)
193 {
194         u32 status;
195
196         status = ixp2000_reg_read(IXP2000_IRQ_THD_STATUS_A_0);
197         if (status == 0)
198                 return IRQ_NONE;
199
200         /*
201          * Any of the eight receive units signaled RX?
202          */
203         if (status & 0x00ff) {
204                 ixp2000_reg_wrb(IXP2000_IRQ_THD_ENABLE_CLEAR_A_0, 0x00ff);
205                 if (likely(__netif_rx_schedule_prep(nds[0]))) {
206                         __netif_rx_schedule(nds[0]);
207                 } else {
208                         printk(KERN_CRIT "ixp2000: irq while polling!!\n");
209                 }
210         }
211
212         /*
213          * Any of the eight transmit units signaled TXdone?
214          */
215         if (status & 0xff00) {
216                 ixp2000_reg_wrb(IXP2000_IRQ_THD_RAW_STATUS_A_0, 0xff00);
217                 ixpdev_tx_complete();
218         }
219
220         return IRQ_HANDLED;
221 }
222
223 #ifdef CONFIG_NET_POLL_CONTROLLER
224 static void ixpdev_poll_controller(struct net_device *dev)
225 {
226         disable_irq(IRQ_IXP2000_THDA0);
227         ixpdev_interrupt(IRQ_IXP2000_THDA0, dev, NULL);
228         enable_irq(IRQ_IXP2000_THDA0);
229 }
230 #endif
231
232 static int ixpdev_open(struct net_device *dev)
233 {
234         struct ixpdev_priv *ip = netdev_priv(dev);
235         int err;
236
237         if (!nds_open++) {
238                 err = request_irq(IRQ_IXP2000_THDA0, ixpdev_interrupt,
239                                         SA_SHIRQ, "ixp2000_eth", nds);
240                 if (err) {
241                         nds_open--;
242                         return err;
243                 }
244
245                 ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_SET_A_0, 0xffff);
246         }
247
248         set_port_admin_status(ip->channel, 1);
249         netif_start_queue(dev);
250
251         return 0;
252 }
253
254 static int ixpdev_close(struct net_device *dev)
255 {
256         struct ixpdev_priv *ip = netdev_priv(dev);
257
258         netif_stop_queue(dev);
259         set_port_admin_status(ip->channel, 0);
260
261         if (!--nds_open) {
262                 ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_CLEAR_A_0, 0xffff);
263                 free_irq(IRQ_IXP2000_THDA0, nds);
264         }
265
266         return 0;
267 }
268
269 struct net_device *ixpdev_alloc(int channel, int sizeof_priv)
270 {
271         struct net_device *dev;
272         struct ixpdev_priv *ip;
273
274         dev = alloc_etherdev(sizeof_priv);
275         if (dev == NULL)
276                 return NULL;
277
278         dev->hard_start_xmit = ixpdev_xmit;
279         dev->poll = ixpdev_poll;
280         dev->open = ixpdev_open;
281         dev->stop = ixpdev_close;
282 #ifdef CONFIG_NET_POLL_CONTROLLER
283         dev->poll_controller = ixpdev_poll_controller;
284 #endif
285
286         dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
287         dev->weight = 64;
288
289         ip = netdev_priv(dev);
290         ip->channel = channel;
291         ip->tx_queue_entries = 0;
292
293         return dev;
294 }
295
296 int ixpdev_init(int __nds_count, struct net_device **__nds,
297                 void (*__set_port_admin_status)(int port, int up))
298 {
299         int i;
300         int err;
301
302         if (RX_BUF_COUNT > 192 || TX_BUF_COUNT > 192) {
303                 static void __too_many_rx_or_tx_buffers(void);
304                 __too_many_rx_or_tx_buffers();
305         }
306
307         printk(KERN_INFO "IXP2000 MSF ethernet driver %s\n", DRV_MODULE_VERSION);
308
309         nds_count = __nds_count;
310         nds = __nds;
311         set_port_admin_status = __set_port_admin_status;
312
313         for (i = 0; i < RX_BUF_COUNT; i++) {
314                 void *buf;
315
316                 buf = (void *)get_zeroed_page(GFP_KERNEL);
317                 if (buf == NULL) {
318                         err = -ENOMEM;
319                         while (--i >= 0)
320                                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
321                         goto err_out;
322                 }
323                 rx_desc[i].buf_addr = virt_to_phys(buf);
324                 rx_desc[i].buf_length = PAGE_SIZE;
325         }
326
327         /* @@@ Maybe we shouldn't be preallocating TX buffers.  */
328         for (i = 0; i < TX_BUF_COUNT; i++) {
329                 void *buf;
330
331                 buf = (void *)get_zeroed_page(GFP_KERNEL);
332                 if (buf == NULL) {
333                         err = -ENOMEM;
334                         while (--i >= 0)
335                                 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
336                         goto err_free_rx;
337                 }
338                 tx_desc[i].buf_addr = virt_to_phys(buf);
339         }
340
341         /* 256 entries, ring status set means 'empty', base address 0x0000.  */
342         ixp2000_reg_write(RING_RX_PENDING_BASE, 0x44000000);
343         ixp2000_reg_write(RING_RX_PENDING_HEAD, 0x00000000);
344         ixp2000_reg_write(RING_RX_PENDING_TAIL, 0x00000000);
345
346         /* 256 entries, ring status set means 'full', base address 0x0400.  */
347         ixp2000_reg_write(RING_RX_DONE_BASE, 0x40000400);
348         ixp2000_reg_write(RING_RX_DONE_HEAD, 0x00000000);
349         ixp2000_reg_write(RING_RX_DONE_TAIL, 0x00000000);
350
351         for (i = 0; i < RX_BUF_COUNT; i++) {
352                 ixp2000_reg_write(RING_RX_PENDING,
353                         RX_BUF_DESC_BASE + (i * sizeof(struct ixpdev_rx_desc)));
354         }
355
356         ixp2000_uengine_load(0, &ixp2400_rx);
357         ixp2000_uengine_start_contexts(0, 0xff);
358
359         /* 256 entries, ring status set means 'empty', base address 0x0800.  */
360         ixp2000_reg_write(RING_TX_PENDING_BASE, 0x44000800);
361         ixp2000_reg_write(RING_TX_PENDING_HEAD, 0x00000000);
362         ixp2000_reg_write(RING_TX_PENDING_TAIL, 0x00000000);
363
364         /* 256 entries, ring status set means 'full', base address 0x0c00.  */
365         ixp2000_reg_write(RING_TX_DONE_BASE, 0x40000c00);
366         ixp2000_reg_write(RING_TX_DONE_HEAD, 0x00000000);
367         ixp2000_reg_write(RING_TX_DONE_TAIL, 0x00000000);
368
369         ixp2000_uengine_load(1, &ixp2400_tx);
370         ixp2000_uengine_start_contexts(1, 0xff);
371
372         for (i = 0; i < nds_count; i++) {
373                 err = register_netdev(nds[i]);
374                 if (err) {
375                         while (--i >= 0)
376                                 unregister_netdev(nds[i]);
377                         goto err_free_tx;
378                 }
379         }
380
381         for (i = 0; i < nds_count; i++) {
382                 printk(KERN_INFO "%s: IXP2000 MSF ethernet (port %d), "
383                         "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x.\n", nds[i]->name, i,
384                         nds[i]->dev_addr[0], nds[i]->dev_addr[1],
385                         nds[i]->dev_addr[2], nds[i]->dev_addr[3],
386                         nds[i]->dev_addr[4], nds[i]->dev_addr[5]);
387         }
388
389         return 0;
390
391 err_free_tx:
392         for (i = 0; i < TX_BUF_COUNT; i++)
393                 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
394
395 err_free_rx:
396         for (i = 0; i < RX_BUF_COUNT; i++)
397                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
398
399 err_out:
400         return err;
401
402
403 void ixpdev_deinit(void)
404 {
405         int i;
406
407         /* @@@ Flush out pending packets.  */
408
409         for (i = 0; i < nds_count; i++)
410                 unregister_netdev(nds[i]);
411
412         ixp2000_uengine_stop_contexts(1, 0xff);
413         ixp2000_uengine_stop_contexts(0, 0xff);
414         ixp2000_uengine_reset(0x3);
415
416         for (i = 0; i < TX_BUF_COUNT; i++)
417                 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
418
419         for (i = 0; i < RX_BUF_COUNT; i++)
420                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
421 }