linux/drivers/net/ixp2000/ixpdev.c
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   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#include "pm3386.h"
  25
  26#define DRV_MODULE_VERSION      "0.2"
  27
  28static int nds_count;
  29static struct net_device **nds;
  30static int nds_open;
  31static void (*set_port_admin_status)(int port, int up);
  32
  33static struct ixpdev_rx_desc * const rx_desc =
  34        (struct ixpdev_rx_desc *)(IXP2000_SRAM0_VIRT_BASE + RX_BUF_DESC_BASE);
  35static struct ixpdev_tx_desc * const tx_desc =
  36        (struct ixpdev_tx_desc *)(IXP2000_SRAM0_VIRT_BASE + TX_BUF_DESC_BASE);
  37static int tx_pointer;
  38
  39
  40static 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        unsigned long flags;
  46
  47        if (unlikely(skb->len > PAGE_SIZE)) {
  48                /* @@@ Count drops.  */
  49                dev_kfree_skb(skb);
  50                return NETDEV_TX_OK;
  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_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
  78static 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(dev, desc->pkt_length + 2);
 113                if (likely(skb != NULL)) {
 114                        skb_reserve(skb, 2);
 115                        skb_copy_to_linear_data(skb, buf, desc->pkt_length);
 116                        skb_put(skb, desc->pkt_length);
 117                        skb->protocol = eth_type_trans(skb, nds[desc->channel]);
 118
 119                        netif_receive_skb(skb);
 120                }
 121
 122err:
 123                ixp2000_reg_write(RING_RX_PENDING, _desc);
 124                processed++;
 125        }
 126
 127        return processed;
 128}
 129
 130/* dev always points to nds[0].  */
 131static 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        napi_complete(napi);
 147        ixp2000_reg_write(IXP2000_IRQ_THD_ENABLE_SET_A_0, 0x00ff);
 148
 149        return rx;
 150}
 151
 152static 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
 192static 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                        __napi_schedule(&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
 227static 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
 235static 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
 259static 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
 275static struct net_device_stats *ixpdev_get_stats(struct net_device *dev)
 276{
 277        struct ixpdev_priv *ip = netdev_priv(dev);
 278
 279        pm3386_get_stats(ip->channel, &(dev->stats));
 280
 281        return &(dev->stats);
 282}
 283
 284static const struct net_device_ops ixpdev_netdev_ops = {
 285        .ndo_open               = ixpdev_open,
 286        .ndo_stop               = ixpdev_close,
 287        .ndo_start_xmit         = ixpdev_xmit,
 288        .ndo_change_mtu         = eth_change_mtu,
 289        .ndo_validate_addr      = eth_validate_addr,
 290        .ndo_set_mac_address    = eth_mac_addr,
 291        .ndo_get_stats          = ixpdev_get_stats,
 292#ifdef CONFIG_NET_POLL_CONTROLLER
 293        .ndo_poll_controller    = ixpdev_poll_controller,
 294#endif
 295};
 296
 297struct net_device *ixpdev_alloc(int channel, int sizeof_priv)
 298{
 299        struct net_device *dev;
 300        struct ixpdev_priv *ip;
 301
 302        dev = alloc_etherdev(sizeof_priv);
 303        if (dev == NULL)
 304                return NULL;
 305
 306        dev->netdev_ops = &ixpdev_netdev_ops;
 307
 308        dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
 309
 310        ip = netdev_priv(dev);
 311        ip->dev = dev;
 312        netif_napi_add(dev, &ip->napi, ixpdev_poll, 64);
 313        ip->channel = channel;
 314        ip->tx_queue_entries = 0;
 315
 316        return dev;
 317}
 318
 319int ixpdev_init(int __nds_count, struct net_device **__nds,
 320                void (*__set_port_admin_status)(int port, int up))
 321{
 322        int i;
 323        int err;
 324
 325        BUILD_BUG_ON(RX_BUF_COUNT > 192 || TX_BUF_COUNT > 192);
 326
 327        printk(KERN_INFO "IXP2000 MSF ethernet driver %s\n", DRV_MODULE_VERSION);
 328
 329        nds_count = __nds_count;
 330        nds = __nds;
 331        set_port_admin_status = __set_port_admin_status;
 332
 333        for (i = 0; i < RX_BUF_COUNT; i++) {
 334                void *buf;
 335
 336                buf = (void *)get_zeroed_page(GFP_KERNEL);
 337                if (buf == NULL) {
 338                        err = -ENOMEM;
 339                        while (--i >= 0)
 340                                free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
 341                        goto err_out;
 342                }
 343                rx_desc[i].buf_addr = virt_to_phys(buf);
 344                rx_desc[i].buf_length = PAGE_SIZE;
 345        }
 346
 347        /* @@@ Maybe we shouldn't be preallocating TX buffers.  */
 348        for (i = 0; i < TX_BUF_COUNT; i++) {
 349                void *buf;
 350
 351                buf = (void *)get_zeroed_page(GFP_KERNEL);
 352                if (buf == NULL) {
 353                        err = -ENOMEM;
 354                        while (--i >= 0)
 355                                free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
 356                        goto err_free_rx;
 357                }
 358                tx_desc[i].buf_addr = virt_to_phys(buf);
 359        }
 360
 361        /* 256 entries, ring status set means 'empty', base address 0x0000.  */
 362        ixp2000_reg_write(RING_RX_PENDING_BASE, 0x44000000);
 363        ixp2000_reg_write(RING_RX_PENDING_HEAD, 0x00000000);
 364        ixp2000_reg_write(RING_RX_PENDING_TAIL, 0x00000000);
 365
 366        /* 256 entries, ring status set means 'full', base address 0x0400.  */
 367        ixp2000_reg_write(RING_RX_DONE_BASE, 0x40000400);
 368        ixp2000_reg_write(RING_RX_DONE_HEAD, 0x00000000);
 369        ixp2000_reg_write(RING_RX_DONE_TAIL, 0x00000000);
 370
 371        for (i = 0; i < RX_BUF_COUNT; i++) {
 372                ixp2000_reg_write(RING_RX_PENDING,
 373                        RX_BUF_DESC_BASE + (i * sizeof(struct ixpdev_rx_desc)));
 374        }
 375
 376        ixp2000_uengine_load(0, &ixp2400_rx);
 377        ixp2000_uengine_start_contexts(0, 0xff);
 378
 379        /* 256 entries, ring status set means 'empty', base address 0x0800.  */
 380        ixp2000_reg_write(RING_TX_PENDING_BASE, 0x44000800);
 381        ixp2000_reg_write(RING_TX_PENDING_HEAD, 0x00000000);
 382        ixp2000_reg_write(RING_TX_PENDING_TAIL, 0x00000000);
 383
 384        /* 256 entries, ring status set means 'full', base address 0x0c00.  */
 385        ixp2000_reg_write(RING_TX_DONE_BASE, 0x40000c00);
 386        ixp2000_reg_write(RING_TX_DONE_HEAD, 0x00000000);
 387        ixp2000_reg_write(RING_TX_DONE_TAIL, 0x00000000);
 388
 389        ixp2000_uengine_load(1, &ixp2400_tx);
 390        ixp2000_uengine_start_contexts(1, 0xff);
 391
 392        for (i = 0; i < nds_count; i++) {
 393                err = register_netdev(nds[i]);
 394                if (err) {
 395                        while (--i >= 0)
 396                                unregister_netdev(nds[i]);
 397                        goto err_free_tx;
 398                }
 399        }
 400
 401        for (i = 0; i < nds_count; i++) {
 402                printk(KERN_INFO "%s: IXP2000 MSF ethernet (port %d), "
 403                        "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x.\n", nds[i]->name, i,
 404                        nds[i]->dev_addr[0], nds[i]->dev_addr[1],
 405                        nds[i]->dev_addr[2], nds[i]->dev_addr[3],
 406                        nds[i]->dev_addr[4], nds[i]->dev_addr[5]);
 407        }
 408
 409        return 0;
 410
 411err_free_tx:
 412        for (i = 0; i < TX_BUF_COUNT; i++)
 413                free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
 414
 415err_free_rx:
 416        for (i = 0; i < RX_BUF_COUNT; i++)
 417                free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
 418
 419err_out:
 420        return err;
 421} 
 422
 423void ixpdev_deinit(void)
 424{
 425        int i;
 426
 427        /* @@@ Flush out pending packets.  */
 428
 429        for (i = 0; i < nds_count; i++)
 430                unregister_netdev(nds[i]);
 431
 432        ixp2000_uengine_stop_contexts(1, 0xff);
 433        ixp2000_uengine_stop_contexts(0, 0xff);
 434        ixp2000_uengine_reset(0x3);
 435
 436        for (i = 0; i < TX_BUF_COUNT; i++)
 437                free_page((unsigned long)phys_to_virt(tx_desc[i].buf_addr));
 438
 439        for (i = 0; i < RX_BUF_COUNT; i++)
 440                free_page((unsigned long)phys_to_virt(rx_desc[i].buf_addr));
 441}
 442