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
  45         if (unlikely(skb->len > PAGE_SIZE)) {
  46                 /* @@@ Count drops.  */
  47                 dev_kfree_skb(skb);
  48                 return 0;
  49         }
  50
  51         entry = tx_pointer;
  52         tx_pointer = (tx_pointer + 1) % TX_BUF_COUNT;
  53
  54         desc = tx_desc + entry;
  55         desc->pkt_length = skb->len;
  56         desc->channel = ip->channel;
  57
  58         skb_copy_and_csum_dev(skb, phys_to_virt(desc->buf_addr));
  59         dev_kfree_skb(skb);
  60
  61         ixp2000_reg_write(RING_TX_PENDING,
  62                 TX_BUF_DESC_BASE + (entry * sizeof(struct ixpdev_tx_desc)));
  63
  64         dev->trans_start = jiffies;
  65
  66         local_irq_disable();
  67         ip->tx_queue_entries++;
  68         if (ip->tx_queue_entries == TX_BUF_COUNT_PER_CHAN)
  69                 netif_stop_queue(dev);
  70         local_irq_enable();
  71
  72         return 0;
  73 }
  74
  75
  76 static int ixpdev_rx(struct net_device *dev, int processed, int budget)
  77 {
  78         while (processed < budget) {
  79                 struct ixpdev_rx_desc *desc;
  80                 struct sk_buff *skb;
  81                 void *buf;
  82                 u32 _desc;
  83
  84                 _desc = ixp2000_reg_read(RING_RX_DONE);
  85                 if (_desc == 0)
  86                         return 0;
  87
  88                 desc = rx_desc +
  89                         ((_desc - RX_BUF_DESC_BASE) / sizeof(struct ixpdev_rx_desc));
  90                 buf = phys_to_virt(desc->buf_addr);
  91
  92                 if (desc->pkt_length < 4 || desc->pkt_length > PAGE_SIZE) {
  93                         printk(KERN_ERR "ixp2000: rx err, length %d\n",
  94                                         desc->pkt_length);
  95                         goto err;
  96                 }
  97
  98                 if (desc->channel < 0 || desc->channel >= nds_count) {
  99                         printk(KERN_ERR "ixp2000: rx err, channel %d\n",
 100                                         desc->channel);
 101                         goto err;
 102                 }
 103
 104                 /* @@@ Make FCS stripping configurable.  */
 105                 desc->pkt_length -= 4;
 106
 107                 if (unlikely(!netif_running(nds[desc->channel])))
 108                         goto err;
 109
 110                 skb = netdev_alloc_skb(dev, desc->pkt_length + 2);
 111                 if (likely(skb != NULL)) {
 112                         skb_reserve(skb, 2);
 113                         skb_copy_to_linear_data(skb, buf, desc->pkt_length);
 114                         skb_put(skb, desc->pkt_length);
 115                         skb->protocol = eth_type_trans(skb, nds[desc->channel]);
 116
 117                         dev->last_rx = jiffies;
 118
 119                         netif_receive_skb(skb);
 120                 }
 121
 122 err:
 123                 ixp2000_reg_write(RING_RX_PENDING, _desc);
 124                 processed++;
 125         }
 126
 127         return processed;
 128 }
 129
 130 /* dev always points to nds[0].  */
 131 static int ixpdev_poll(struct napi_struct *napi, int budget)
 132 {
 133         struct ixpdev_priv *ip = container_of(napi, struct ixpdev_priv, napi);
 134         struct net_device *dev = ip->dev;
 135         int rx;
 136
 137         rx = 0;
 138         do {
 139                 ixp2000_reg_write(IXP2000_IRQ_THD_RAW_STATUS_A_0, 0x00ff);
 140
 141                 rx = ixpdev_rx(dev, rx, budget);
 142                 if (rx >= budget)
 143                         break;
 144         } while (ixp2000_reg_read(IXP2000_IRQ_THD_RAW_STATUS_A_0) & 0x00ff);
 145
 146         netif_rx_complete(dev, napi);
 147         ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_SET_A_0, 0x00ff);
 148
 149         return rx;
 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)
 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                 struct net_device *dev = nds[0];
 205                 struct ixpdev_priv *ip = netdev_priv(dev);
 206
 207                 ixp2000_reg_wrb(IXP2000_IRQ_THD_ENABLE_CLEAR_A_0, 0x00ff);
 208                 if (likely(napi_schedule_prep(&ip->napi))) {
 209                         __netif_rx_schedule(dev, &ip->napi);
 210                 } else {
 211                         printk(KERN_CRIT "ixp2000: irq while polling!!\n");
 212                 }
 213         }
 214
 215         /*
 216          * Any of the eight transmit units signaled TXdone?
 217          */
 218         if (status & 0xff00) {
 219                 ixp2000_reg_wrb(IXP2000_IRQ_THD_RAW_STATUS_A_0, 0xff00);
 220                 ixpdev_tx_complete();
 221         }
 222
 223         return IRQ_HANDLED;
 224 }
 225
 226 #ifdef CONFIG_NET_POLL_CONTROLLER
 227 static void ixpdev_poll_controller(struct net_device *dev)
 228 {
 229         disable_irq(IRQ_IXP2000_THDA0);
 230         ixpdev_interrupt(IRQ_IXP2000_THDA0, dev);
 231         enable_irq(IRQ_IXP2000_THDA0);
 232 }
 233 #endif
 234
 235 static int ixpdev_open(struct net_device *dev)
 236 {
 237         struct ixpdev_priv *ip = netdev_priv(dev);
 238         int err;
 239
 240         napi_enable(&ip->napi);
 241         if (!nds_open++) {
 242                 err = request_irq(IRQ_IXP2000_THDA0, ixpdev_interrupt,
 243                                         IRQF_SHARED, "ixp2000_eth", nds);
 244                 if (err) {
 245                         nds_open--;
 246                         napi_disable(&ip->napi);
 247                         return err;
 248                 }
 249
 250                 ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_SET_A_0, 0xffff);
 251         }
 252
 253         set_port_admin_status(ip->channel, 1);
 254         netif_start_queue(dev);
 255
 256         return 0;
 257 }
 258
 259 static int ixpdev_close(struct net_device *dev)
 260 {
 261         struct ixpdev_priv *ip = netdev_priv(dev);
 262
 263         netif_stop_queue(dev);
 264         napi_disable(&ip->napi);
 265         set_port_admin_status(ip->channel, 0);
 266
 267         if (!--nds_open) {
 268                 ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_CLEAR_A_0, 0xffff);
 269                 free_irq(IRQ_IXP2000_THDA0, nds);
 270         }
 271
 272         return 0;
 273 }
 274
 275 struct net_device *ixpdev_alloc(int channel, int sizeof_priv)
 276 {
 277         struct net_device *dev;
 278         struct ixpdev_priv *ip;
 279
 280         dev = alloc_etherdev(sizeof_priv);
 281         if (dev == NULL)
 282                 return NULL;
 283
 284         dev->hard_start_xmit = ixpdev_xmit;
 285         dev->open = ixpdev_open;
 286         dev->stop = ixpdev_close;
 287 #ifdef CONFIG_NET_POLL_CONTROLLER
 288         dev->poll_controller = ixpdev_poll_controller;
 289 #endif
 290
 291         dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
 292
 293         ip = netdev_priv(dev);
 294         ip->dev = dev;
 295         netif_napi_add(dev, &ip->napi, ixpdev_poll, 64);
 296         ip->channel = channel;
 297         ip->tx_queue_entries = 0;
 298
 299         return dev;
 300 }
 301
 302 int ixpdev_init(int __nds_count, struct net_device **__nds,
 303                 void (*__set_port_admin_status)(int port, int up))
 304 {
 305         int i;
 306         int err;
 307
 308         BUILD_BUG_ON(RX_BUF_COUNT > 192 || TX_BUF_COUNT > 192);
 309
 310         printk(KERN_INFO "IXP2000 MSF ethernet driver %s\n", DRV_MODULE_VERSION);
 311
 312         nds_count = __nds_count;
 313         nds = __nds;
 314         set_port_admin_status = __set_port_admin_status;
 315
 316         for (i = 0; i < RX_BUF_COUNT; i++) {
 317                 void *buf;
 318
 319                 buf = (void *)get_zeroed_page(GFP_KERNEL);
 320                 if (buf == NULL) {
 321                         err = -ENOMEM;
 322                         while (--i >= 0)
 323                                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
 324                         goto err_out;
 325                 }
 326                 rx_desc[i].buf_addr = virt_to_phys(buf);
 327                 rx_desc[i].buf_length = PAGE_SIZE;
 328         }
 329
 330         /* @@@ Maybe we shouldn't be preallocating TX buffers.  */
 331         for (i = 0; i < TX_BUF_COUNT; i++) {
 332                 void *buf;
 333
 334                 buf = (void *)get_zeroed_page(GFP_KERNEL);
 335                 if (buf == NULL) {
 336                         err = -ENOMEM;
 337                         while (--i >= 0)
 338                                 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
 339                         goto err_free_rx;
 340                 }
 341                 tx_desc[i].buf_addr = virt_to_phys(buf);
 342         }
 343
 344         /* 256 entries, ring status set means 'empty', base address 0x0000.  */
 345         ixp2000_reg_write(RING_RX_PENDING_BASE, 0x44000000);
 346         ixp2000_reg_write(RING_RX_PENDING_HEAD, 0x00000000);
 347         ixp2000_reg_write(RING_RX_PENDING_TAIL, 0x00000000);
 348
 349         /* 256 entries, ring status set means 'full', base address 0x0400.  */
 350         ixp2000_reg_write(RING_RX_DONE_BASE, 0x40000400);
 351         ixp2000_reg_write(RING_RX_DONE_HEAD, 0x00000000);
 352         ixp2000_reg_write(RING_RX_DONE_TAIL, 0x00000000);
 353
 354         for (i = 0; i < RX_BUF_COUNT; i++) {
 355                 ixp2000_reg_write(RING_RX_PENDING,
 356                         RX_BUF_DESC_BASE + (i * sizeof(struct ixpdev_rx_desc)));
 357         }
 358
 359         ixp2000_uengine_load(0, &ixp2400_rx);
 360         ixp2000_uengine_start_contexts(0, 0xff);
 361
 362         /* 256 entries, ring status set means 'empty', base address 0x0800.  */
 363         ixp2000_reg_write(RING_TX_PENDING_BASE, 0x44000800);
 364         ixp2000_reg_write(RING_TX_PENDING_HEAD, 0x00000000);
 365         ixp2000_reg_write(RING_TX_PENDING_TAIL, 0x00000000);
 366
 367         /* 256 entries, ring status set means 'full', base address 0x0c00.  */
 368         ixp2000_reg_write(RING_TX_DONE_BASE, 0x40000c00);
 369         ixp2000_reg_write(RING_TX_DONE_HEAD, 0x00000000);
 370         ixp2000_reg_write(RING_TX_DONE_TAIL, 0x00000000);
 371
 372         ixp2000_uengine_load(1, &ixp2400_tx);
 373         ixp2000_uengine_start_contexts(1, 0xff);
 374
 375         for (i = 0; i < nds_count; i++) {
 376                 err = register_netdev(nds[i]);
 377                 if (err) {
 378                         while (--i >= 0)
 379                                 unregister_netdev(nds[i]);
 380                         goto err_free_tx;
 381                 }
 382         }
 383
 384         for (i = 0; i < nds_count; i++) {
 385                 printk(KERN_INFO "%s: IXP2000 MSF ethernet (port %d), "
 386                         "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x.\n", nds[i]->name, i,
 387                         nds[i]->dev_addr[0], nds[i]->dev_addr[1],
 388                         nds[i]->dev_addr[2], nds[i]->dev_addr[3],
 389                         nds[i]->dev_addr[4], nds[i]->dev_addr[5]);
 390         }
 391
 392         return 0;
 393
 394 err_free_tx:
 395         for (i = 0; i < TX_BUF_COUNT; i++)
 396                 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
 397
 398 err_free_rx:
 399         for (i = 0; i < RX_BUF_COUNT; i++)
 400                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
 401
 402 err_out:
 403         return err;
 404 }
 405
 406 void ixpdev_deinit(void)
 407 {
 408         int i;
 409
 410         /* @@@ Flush out pending packets.  */
 411
 412         for (i = 0; i < nds_count; i++)
 413                 unregister_netdev(nds[i]);
 414
 415         ixp2000_uengine_stop_contexts(1, 0xff);
 416         ixp2000_uengine_stop_contexts(0, 0xff);
 417         ixp2000_uengine_reset(0x3);
 418
 419         for (i = 0; i < TX_BUF_COUNT; i++)
 420                 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
 421
 422         for (i = 0; i < RX_BUF_COUNT; i++)
 423                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
 424 }