127243461a5161c09f33e5bdbf80f8cc1286712f
[linux-2.6.git] / 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/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/moduleparam.h>
18 #include <asm/hardware/uengine.h>
19 #include <asm/io.h>
20 #include "ixp2400_rx.ucode"
21 #include "ixp2400_tx.ucode"
22 #include "ixpdev_priv.h"
23 #include "ixpdev.h"
24
25 #define DRV_MODULE_VERSION      "0.2"
26
27 static int nds_count;
28 static struct net_device **nds;
29 static int nds_open;
30 static void (*set_port_admin_status)(int port, int up);
31
32 static struct ixpdev_rx_desc * const rx_desc =
33         (struct ixpdev_rx_desc *)(IXP2000_SRAM0_VIRT_BASE + RX_BUF_DESC_BASE);
34 static struct ixpdev_tx_desc * const tx_desc =
35         (struct ixpdev_tx_desc *)(IXP2000_SRAM0_VIRT_BASE + TX_BUF_DESC_BASE);
36 static int tx_pointer;
37
38
39 static int ixpdev_xmit(struct sk_buff *skb, struct net_device *dev)
40 {
41         struct ixpdev_priv *ip = netdev_priv(dev);
42         struct ixpdev_tx_desc *desc;
43         int entry;
44         unsigned long flags;
45
46         if (unlikely(skb->len > PAGE_SIZE)) {
47                 /* @@@ Count drops.  */
48                 dev_kfree_skb(skb);
49                 return NETDEV_TX_OK;
50         }
51
52         entry = tx_pointer;
53         tx_pointer = (tx_pointer + 1) % TX_BUF_COUNT;
54
55         desc = tx_desc + entry;
56         desc->pkt_length = skb->len;
57         desc->channel = ip->channel;
58
59         skb_copy_and_csum_dev(skb, phys_to_virt(desc->buf_addr));
60         dev_kfree_skb(skb);
61
62         ixp2000_reg_write(RING_TX_PENDING,
63                 TX_BUF_DESC_BASE + (entry * sizeof(struct ixpdev_tx_desc)));
64
65         dev->trans_start = jiffies;
66
67         local_irq_save(flags);
68         ip->tx_queue_entries++;
69         if (ip->tx_queue_entries == TX_BUF_COUNT_PER_CHAN)
70                 netif_stop_queue(dev);
71         local_irq_restore(flags);
72
73         return NETDEV_TX_OK;
74 }
75
76
77 static int ixpdev_rx(struct net_device *dev, int processed, int budget)
78 {
79         while (processed < budget) {
80                 struct ixpdev_rx_desc *desc;
81                 struct sk_buff *skb;
82                 void *buf;
83                 u32 _desc;
84
85                 _desc = ixp2000_reg_read(RING_RX_DONE);
86                 if (_desc == 0)
87                         return 0;
88
89                 desc = rx_desc +
90                         ((_desc - RX_BUF_DESC_BASE) / sizeof(struct ixpdev_rx_desc));
91                 buf = phys_to_virt(desc->buf_addr);
92
93                 if (desc->pkt_length < 4 || desc->pkt_length > PAGE_SIZE) {
94                         printk(KERN_ERR "ixp2000: rx err, length %d\n",
95                                         desc->pkt_length);
96                         goto err;
97                 }
98
99                 if (desc->channel < 0 || desc->channel >= nds_count) {
100                         printk(KERN_ERR "ixp2000: rx err, channel %d\n",
101                                         desc->channel);
102                         goto err;
103                 }
104
105                 /* @@@ Make FCS stripping configurable.  */
106                 desc->pkt_length -= 4;
107
108                 if (unlikely(!netif_running(nds[desc->channel])))
109                         goto err;
110
111                 skb = netdev_alloc_skb(dev, desc->pkt_length + 2);
112                 if (likely(skb != NULL)) {
113                         skb_reserve(skb, 2);
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].  */
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
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
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
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
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
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
274 static const struct net_device_ops ixpdev_netdev_ops = {
275         .ndo_open               = ixpdev_open,
276         .ndo_stop               = ixpdev_close,
277         .ndo_start_xmit         = ixpdev_xmit,
278         .ndo_change_mtu         = eth_change_mtu,
279         .ndo_validate_addr      = eth_validate_addr,
280         .ndo_set_mac_address    = eth_mac_addr,
281 #ifdef CONFIG_NET_POLL_CONTROLLER
282         .ndo_poll_controller    = ixpdev_poll_controller,
283 #endif
284 };
285
286 struct net_device *ixpdev_alloc(int channel, int sizeof_priv)
287 {
288         struct net_device *dev;
289         struct ixpdev_priv *ip;
290
291         dev = alloc_etherdev(sizeof_priv);
292         if (dev == NULL)
293                 return NULL;
294
295         dev->netdev_ops = &ixpdev_netdev_ops;
296
297         dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
298
299         ip = netdev_priv(dev);
300         ip->dev = dev;
301         netif_napi_add(dev, &ip->napi, ixpdev_poll, 64);
302         ip->channel = channel;
303         ip->tx_queue_entries = 0;
304
305         return dev;
306 }
307
308 int ixpdev_init(int __nds_count, struct net_device **__nds,
309                 void (*__set_port_admin_status)(int port, int up))
310 {
311         int i;
312         int err;
313
314         BUILD_BUG_ON(RX_BUF_COUNT > 192 || TX_BUF_COUNT > 192);
315
316         printk(KERN_INFO "IXP2000 MSF ethernet driver %s\n", DRV_MODULE_VERSION);
317
318         nds_count = __nds_count;
319         nds = __nds;
320         set_port_admin_status = __set_port_admin_status;
321
322         for (i = 0; i < RX_BUF_COUNT; i++) {
323                 void *buf;
324
325                 buf = (void *)get_zeroed_page(GFP_KERNEL);
326                 if (buf == NULL) {
327                         err = -ENOMEM;
328                         while (--i >= 0)
329                                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
330                         goto err_out;
331                 }
332                 rx_desc[i].buf_addr = virt_to_phys(buf);
333                 rx_desc[i].buf_length = PAGE_SIZE;
334         }
335
336         /* @@@ Maybe we shouldn't be preallocating TX buffers.  */
337         for (i = 0; i < TX_BUF_COUNT; i++) {
338                 void *buf;
339
340                 buf = (void *)get_zeroed_page(GFP_KERNEL);
341                 if (buf == NULL) {
342                         err = -ENOMEM;
343                         while (--i >= 0)
344                                 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
345                         goto err_free_rx;
346                 }
347                 tx_desc[i].buf_addr = virt_to_phys(buf);
348         }
349
350         /* 256 entries, ring status set means 'empty', base address 0x0000.  */
351         ixp2000_reg_write(RING_RX_PENDING_BASE, 0x44000000);
352         ixp2000_reg_write(RING_RX_PENDING_HEAD, 0x00000000);
353         ixp2000_reg_write(RING_RX_PENDING_TAIL, 0x00000000);
354
355         /* 256 entries, ring status set means 'full', base address 0x0400.  */
356         ixp2000_reg_write(RING_RX_DONE_BASE, 0x40000400);
357         ixp2000_reg_write(RING_RX_DONE_HEAD, 0x00000000);
358         ixp2000_reg_write(RING_RX_DONE_TAIL, 0x00000000);
359
360         for (i = 0; i < RX_BUF_COUNT; i++) {
361                 ixp2000_reg_write(RING_RX_PENDING,
362                         RX_BUF_DESC_BASE + (i * sizeof(struct ixpdev_rx_desc)));
363         }
364
365         ixp2000_uengine_load(0, &ixp2400_rx);
366         ixp2000_uengine_start_contexts(0, 0xff);
367
368         /* 256 entries, ring status set means 'empty', base address 0x0800.  */
369         ixp2000_reg_write(RING_TX_PENDING_BASE, 0x44000800);
370         ixp2000_reg_write(RING_TX_PENDING_HEAD, 0x00000000);
371         ixp2000_reg_write(RING_TX_PENDING_TAIL, 0x00000000);
372
373         /* 256 entries, ring status set means 'full', base address 0x0c00.  */
374         ixp2000_reg_write(RING_TX_DONE_BASE, 0x40000c00);
375         ixp2000_reg_write(RING_TX_DONE_HEAD, 0x00000000);
376         ixp2000_reg_write(RING_TX_DONE_TAIL, 0x00000000);
377
378         ixp2000_uengine_load(1, &ixp2400_tx);
379         ixp2000_uengine_start_contexts(1, 0xff);
380
381         for (i = 0; i < nds_count; i++) {
382                 err = register_netdev(nds[i]);
383                 if (err) {
384                         while (--i >= 0)
385                                 unregister_netdev(nds[i]);
386                         goto err_free_tx;
387                 }
388         }
389
390         for (i = 0; i < nds_count; i++) {
391                 printk(KERN_INFO "%s: IXP2000 MSF ethernet (port %d), "
392                         "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x.\n", nds[i]->name, i,
393                         nds[i]->dev_addr[0], nds[i]->dev_addr[1],
394                         nds[i]->dev_addr[2], nds[i]->dev_addr[3],
395                         nds[i]->dev_addr[4], nds[i]->dev_addr[5]);
396         }
397
398         return 0;
399
400 err_free_tx:
401         for (i = 0; i < TX_BUF_COUNT; i++)
402                 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
403
404 err_free_rx:
405         for (i = 0; i < RX_BUF_COUNT; i++)
406                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
407
408 err_out:
409         return err;
410
411
412 void ixpdev_deinit(void)
413 {
414         int i;
415
416         /* @@@ Flush out pending packets.  */
417
418         for (i = 0; i < nds_count; i++)
419                 unregister_netdev(nds[i]);
420
421         ixp2000_uengine_stop_contexts(1, 0xff);
422         ixp2000_uengine_stop_contexts(0, 0xff);
423         ixp2000_uengine_reset(0x3);
424
425         for (i = 0; i < TX_BUF_COUNT; i++)
426                 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
427
428         for (i = 0; i < RX_BUF_COUNT; i++)
429                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
430 }