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/mach-types.h>
  20 #include <asm/io.h>
  21 #include "ixp2400_rx.ucode"
  22 #include "ixp2400_tx.ucode"
  23 #include "ixpdev_priv.h"
  24 #include "ixpdev.h"
  25
  26 #define DRV_MODULE_VERSION      "0.2"
  27
  28 static int nds_count;
  29 static struct net_device **nds;
  30 static int nds_open;
  31 static void (*set_port_admin_status)(int port, int up);
  32
  33 static struct ixpdev_rx_desc * const rx_desc =
  34         (struct ixpdev_rx_desc *)(IXP2000_SRAM0_VIRT_BASE + RX_BUF_DESC_BASE);
  35 static struct ixpdev_tx_desc * const tx_desc =
  36         (struct ixpdev_tx_desc *)(IXP2000_SRAM0_VIRT_BASE + TX_BUF_DESC_BASE);
  37 static int tx_pointer;
  38
  39
  40 static int ixpdev_xmit(struct sk_buff *skb, struct net_device *dev)
  41 {
  42         struct ixpdev_priv *ip = netdev_priv(dev);
  43         struct ixpdev_tx_desc *desc;
  44         int entry;
  45
  46         if (unlikely(skb->len > PAGE_SIZE)) {
  47                 /* @@@ Count drops.  */
  48                 dev_kfree_skb(skb);
  49                 return 0;
  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_disable();
  68         ip->tx_queue_entries++;
  69         if (ip->tx_queue_entries == TX_BUF_COUNT_PER_CHAN)
  70                 netif_stop_queue(dev);
  71         local_irq_enable();
  72
  73         return 0;
  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                         dev->last_rx = jiffies;
 119
 120                         netif_receive_skb(skb);
 121                 }
 122
 123 err:
 124                 ixp2000_reg_write(RING_RX_PENDING, _desc);
 125                 processed++;
 126         }
 127
 128         return processed;
 129 }
 130
 131 /* dev always points to nds[0].  */
 132 static int ixpdev_poll(struct napi_struct *napi, int budget)
 133 {
 134         struct ixpdev_priv *ip = container_of(napi, struct ixpdev_priv, napi);
 135         struct net_device *dev = ip->dev;
 136         int rx;
 137
 138         rx = 0;
 139         do {
 140                 ixp2000_reg_write(IXP2000_IRQ_THD_RAW_STATUS_A_0, 0x00ff);
 141
 142                 rx = ixpdev_rx(dev, rx, budget);
 143                 if (rx >= budget)
 144                         break;
 145         } while (ixp2000_reg_read(IXP2000_IRQ_THD_RAW_STATUS_A_0) & 0x00ff);
 146
 147         netif_rx_complete(dev, napi);
 148         ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_SET_A_0, 0x00ff);
 149
 150         return rx;
 151 }
 152
 153 static void ixpdev_tx_complete(void)
 154 {
 155         int channel;
 156         u32 wake;
 157
 158         wake = 0;
 159         while (1) {
 160                 struct ixpdev_priv *ip;
 161                 u32 desc;
 162                 int entry;
 163
 164                 desc = ixp2000_reg_read(RING_TX_DONE);
 165                 if (desc == 0)
 166                         break;
 167
 168                 /* @@@ Check whether entries come back in order.  */
 169                 entry = (desc - TX_BUF_DESC_BASE) / sizeof(struct ixpdev_tx_desc);
 170                 channel = tx_desc[entry].channel;
 171
 172                 if (channel < 0 || channel >= nds_count) {
 173                         printk(KERN_ERR "ixp2000: txcomp channel index "
 174                                         "out of bounds (%d, %.8i, %d)\n",
 175                                         channel, (unsigned int)desc, entry);
 176                         continue;
 177                 }
 178
 179                 ip = netdev_priv(nds[channel]);
 180                 if (ip->tx_queue_entries == TX_BUF_COUNT_PER_CHAN)
 181                         wake |= 1 << channel;
 182                 ip->tx_queue_entries--;
 183         }
 184
 185         for (channel = 0; wake != 0; channel++) {
 186                 if (wake & (1 << channel)) {
 187                         netif_wake_queue(nds[channel]);
 188                         wake &= ~(1 << channel);
 189                 }
 190         }
 191 }
 192
 193 static irqreturn_t ixpdev_interrupt(int irq, void *dev_id)
 194 {
 195         u32 status;
 196
 197         status = ixp2000_reg_read(IXP2000_IRQ_THD_STATUS_A_0);
 198         if (status == 0)
 199                 return IRQ_NONE;
 200
 201         /*
 202          * Any of the eight receive units signaled RX?
 203          */
 204         if (status & 0x00ff) {
 205                 struct net_device *dev = nds[0];
 206                 struct ixpdev_priv *ip = netdev_priv(dev);
 207
 208                 ixp2000_reg_wrb(IXP2000_IRQ_THD_ENABLE_CLEAR_A_0, 0x00ff);
 209                 if (likely(napi_schedule_prep(&ip->napi))) {
 210                         __netif_rx_schedule(dev, &ip->napi);
 211                 } else {
 212                         printk(KERN_CRIT "ixp2000: irq while polling!!\n");
 213                 }
 214         }
 215
 216         /*
 217          * Any of the eight transmit units signaled TXdone?
 218          */
 219         if (status & 0xff00) {
 220                 ixp2000_reg_wrb(IXP2000_IRQ_THD_RAW_STATUS_A_0, 0xff00);
 221                 ixpdev_tx_complete();
 222         }
 223
 224         return IRQ_HANDLED;
 225 }
 226
 227 #ifdef CONFIG_NET_POLL_CONTROLLER
 228 static void ixpdev_poll_controller(struct net_device *dev)
 229 {
 230         disable_irq(IRQ_IXP2000_THDA0);
 231         ixpdev_interrupt(IRQ_IXP2000_THDA0, dev);
 232         enable_irq(IRQ_IXP2000_THDA0);
 233 }
 234 #endif
 235
 236 static int ixpdev_open(struct net_device *dev)
 237 {
 238         struct ixpdev_priv *ip = netdev_priv(dev);
 239         int err;
 240
 241         napi_enable(&ip->napi);
 242         if (!nds_open++) {
 243                 err = request_irq(IRQ_IXP2000_THDA0, ixpdev_interrupt,
 244                                         IRQF_SHARED, "ixp2000_eth", nds);
 245                 if (err) {
 246                         nds_open--;
 247                         napi_disable(&ip->napi);
 248                         return err;
 249                 }
 250
 251                 ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_SET_A_0, 0xffff);
 252         }
 253
 254         set_port_admin_status(ip->channel, 1);
 255         netif_start_queue(dev);
 256
 257         return 0;
 258 }
 259
 260 static int ixpdev_close(struct net_device *dev)
 261 {
 262         struct ixpdev_priv *ip = netdev_priv(dev);
 263
 264         netif_stop_queue(dev);
 265         napi_disable(&ip->napi);
 266         set_port_admin_status(ip->channel, 0);
 267
 268         if (!--nds_open) {
 269                 ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_CLEAR_A_0, 0xffff);
 270                 free_irq(IRQ_IXP2000_THDA0, nds);
 271         }
 272
 273         return 0;
 274 }
 275
 276 struct net_device *ixpdev_alloc(int channel, int sizeof_priv)
 277 {
 278         struct net_device *dev;
 279         struct ixpdev_priv *ip;
 280
 281         dev = alloc_etherdev(sizeof_priv);
 282         if (dev == NULL)
 283                 return NULL;
 284
 285         dev->hard_start_xmit = ixpdev_xmit;
 286         dev->open = ixpdev_open;
 287         dev->stop = ixpdev_close;
 288 #ifdef CONFIG_NET_POLL_CONTROLLER
 289         dev->poll_controller = ixpdev_poll_controller;
 290 #endif
 291
 292         dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
 293
 294         ip = netdev_priv(dev);
 295         ip->dev = dev;
 296         netif_napi_add(dev, &ip->napi, ixpdev_poll, 64);
 297         ip->channel = channel;
 298         ip->tx_queue_entries = 0;
 299
 300         return dev;
 301 }
 302
 303 int ixpdev_init(int __nds_count, struct net_device **__nds,
 304                 void (*__set_port_admin_status)(int port, int up))
 305 {
 306         int i;
 307         int err;
 308
 309         BUILD_BUG_ON(RX_BUF_COUNT > 192 || TX_BUF_COUNT > 192);
 310
 311         printk(KERN_INFO "IXP2000 MSF ethernet driver %s\n", DRV_MODULE_VERSION);
 312
 313         nds_count = __nds_count;
 314         nds = __nds;
 315         set_port_admin_status = __set_port_admin_status;
 316
 317         for (i = 0; i < RX_BUF_COUNT; i++) {
 318                 void *buf;
 319
 320                 buf = (void *)get_zeroed_page(GFP_KERNEL);
 321                 if (buf == NULL) {
 322                         err = -ENOMEM;
 323                         while (--i >= 0)
 324                                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
 325                         goto err_out;
 326                 }
 327                 rx_desc[i].buf_addr = virt_to_phys(buf);
 328                 rx_desc[i].buf_length = PAGE_SIZE;
 329         }
 330
 331         /* @@@ Maybe we shouldn't be preallocating TX buffers.  */
 332         for (i = 0; i < TX_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(tx_desc[i].buf_addr));
 340                         goto err_free_rx;
 341                 }
 342                 tx_desc[i].buf_addr = virt_to_phys(buf);
 343         }
 344
 345         /* 256 entries, ring status set means 'empty', base address 0x0000.  */
 346         ixp2000_reg_write(RING_RX_PENDING_BASE, 0x44000000);
 347         ixp2000_reg_write(RING_RX_PENDING_HEAD, 0x00000000);
 348         ixp2000_reg_write(RING_RX_PENDING_TAIL, 0x00000000);
 349
 350         /* 256 entries, ring status set means 'full', base address 0x0400.  */
 351         ixp2000_reg_write(RING_RX_DONE_BASE, 0x40000400);
 352         ixp2000_reg_write(RING_RX_DONE_HEAD, 0x00000000);
 353         ixp2000_reg_write(RING_RX_DONE_TAIL, 0x00000000);
 354
 355         for (i = 0; i < RX_BUF_COUNT; i++) {
 356                 ixp2000_reg_write(RING_RX_PENDING,
 357                         RX_BUF_DESC_BASE + (i * sizeof(struct ixpdev_rx_desc)));
 358         }
 359
 360         ixp2000_uengine_load(0, &ixp2400_rx);
 361         ixp2000_uengine_start_contexts(0, 0xff);
 362
 363         /* 256 entries, ring status set means 'empty', base address 0x0800.  */
 364         ixp2000_reg_write(RING_TX_PENDING_BASE, 0x44000800);
 365         ixp2000_reg_write(RING_TX_PENDING_HEAD, 0x00000000);
 366         ixp2000_reg_write(RING_TX_PENDING_TAIL, 0x00000000);
 367
 368         /* 256 entries, ring status set means 'full', base address 0x0c00.  */
 369         ixp2000_reg_write(RING_TX_DONE_BASE, 0x40000c00);
 370         ixp2000_reg_write(RING_TX_DONE_HEAD, 0x00000000);
 371         ixp2000_reg_write(RING_TX_DONE_TAIL, 0x00000000);
 372
 373         ixp2000_uengine_load(1, &ixp2400_tx);
 374         ixp2000_uengine_start_contexts(1, 0xff);
 375
 376         for (i = 0; i < nds_count; i++) {
 377                 err = register_netdev(nds[i]);
 378                 if (err) {
 379                         while (--i >= 0)
 380                                 unregister_netdev(nds[i]);
 381                         goto err_free_tx;
 382                 }
 383         }
 384
 385         for (i = 0; i < nds_count; i++) {
 386                 printk(KERN_INFO "%s: IXP2000 MSF ethernet (port %d), "
 387                         "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x.\n", nds[i]->name, i,
 388                         nds[i]->dev_addr[0], nds[i]->dev_addr[1],
 389                         nds[i]->dev_addr[2], nds[i]->dev_addr[3],
 390                         nds[i]->dev_addr[4], nds[i]->dev_addr[5]);
 391         }
 392
 393         return 0;
 394
 395 err_free_tx:
 396         for (i = 0; i < TX_BUF_COUNT; i++)
 397                 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
 398
 399 err_free_rx:
 400         for (i = 0; i < RX_BUF_COUNT; i++)
 401                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
 402
 403 err_out:
 404         return err;
 405 }
 406
 407 void ixpdev_deinit(void)
 408 {
 409         int i;
 410
 411         /* @@@ Flush out pending packets.  */
 412
 413         for (i = 0; i < nds_count; i++)
 414                 unregister_netdev(nds[i]);
 415
 416         ixp2000_uengine_stop_contexts(1, 0xff);
 417         ixp2000_uengine_stop_contexts(0, 0xff);
 418         ixp2000_uengine_reset(0x3);
 419
 420         for (i = 0; i < TX_BUF_COUNT; i++)
 421                 free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
 422
 423         for (i = 0; i < RX_BUF_COUNT; i++)
 424                 free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
 425 }