kernel/drivers/staging/octeon/ethernet-tx.c

   1 /*********************************************************************
   2  * Author: Cavium Networks
   3  *
   4  * Contact: support@caviumnetworks.com
   5  * This file is part of the OCTEON SDK
   6  *
   7  * Copyright (c) 2003-2010 Cavium Networks
   8  *
   9  * This file is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License, Version 2, as
  11  * published by the Free Software Foundation.
  12  *
  13  * This file is distributed in the hope that it will be useful, but
  14  * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
  15  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
  16  * NONINFRINGEMENT.  See the GNU General Public License for more
  17  * details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this file; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  22  * or visit http://www.gnu.org/licenses/.
  23  *
  24  * This file may also be available under a different license from Cavium.
  25  * Contact Cavium Networks for more information
  26 *********************************************************************/
  27 #include <linux/module.h>
  28 #include <linux/kernel.h>
  29 #include <linux/netdevice.h>
  30 #include <linux/etherdevice.h>
  31 #include <linux/ip.h>
  32 #include <linux/ratelimit.h>
  33 #include <linux/string.h>
  34 #include <linux/interrupt.h>
  35 #include <net/dst.h>
  36 #ifdef CONFIG_XFRM
  37 #include <linux/xfrm.h>
  38 #include <net/xfrm.h>
  39 #endif /* CONFIG_XFRM */
  40
  41 #include <linux/atomic.h>
  42
  43 #include <asm/octeon/octeon.h>
  44
  45 #include "ethernet-defines.h"
  46 #include "octeon-ethernet.h"
  47 #include "ethernet-tx.h"
  48 #include "ethernet-util.h"
  49
  50 #include <asm/octeon/cvmx-wqe.h>
  51 #include <asm/octeon/cvmx-fau.h>
  52 #include <asm/octeon/cvmx-pip.h>
  53 #include <asm/octeon/cvmx-pko.h>
  54 #include <asm/octeon/cvmx-helper.h>
  55
  56 #include <asm/octeon/cvmx-gmxx-defs.h>
  57
  58 #define CVM_OCT_SKB_CB(skb)     ((u64 *)((skb)->cb))
  59
  60 /*
  61  * You can define GET_SKBUFF_QOS() to override how the skbuff output
  62  * function determines which output queue is used. The default
  63  * implementation always uses the base queue for the port. If, for
  64  * example, you wanted to use the skb->priority field, define
  65  * GET_SKBUFF_QOS as: #define GET_SKBUFF_QOS(skb) ((skb)->priority)
  66  */
  67 #ifndef GET_SKBUFF_QOS
  68 #define GET_SKBUFF_QOS(skb) 0
  69 #endif
  70
  71 static void cvm_oct_tx_do_cleanup(unsigned long arg);
  72 static DECLARE_TASKLET(cvm_oct_tx_cleanup_tasklet, cvm_oct_tx_do_cleanup, 0);
  73
  74 /* Maximum number of SKBs to try to free per xmit packet. */
  75 #define MAX_SKB_TO_FREE (MAX_OUT_QUEUE_DEPTH * 2)
  76
  77 static inline int32_t cvm_oct_adjust_skb_to_free(int32_t skb_to_free, int fau)
  78 {
  79         int32_t undo;
  80
  81         undo = skb_to_free > 0 ? MAX_SKB_TO_FREE : skb_to_free +
  82                                                    MAX_SKB_TO_FREE;
  83         if (undo > 0)
  84                 cvmx_fau_atomic_add32(fau, -undo);
  85         skb_to_free = -skb_to_free > MAX_SKB_TO_FREE ? MAX_SKB_TO_FREE :
  86                                                        -skb_to_free;
  87         return skb_to_free;
  88 }
  89
  90 static void cvm_oct_kick_tx_poll_watchdog(void)
  91 {
  92         union cvmx_ciu_timx ciu_timx;
  93
  94         ciu_timx.u64 = 0;
  95         ciu_timx.s.one_shot = 1;
  96         ciu_timx.s.len = cvm_oct_tx_poll_interval;
  97         cvmx_write_csr(CVMX_CIU_TIMX(1), ciu_timx.u64);
  98 }
  99
 100 static void cvm_oct_free_tx_skbs(struct net_device *dev)
 101 {
 102         int32_t skb_to_free;
 103         int qos, queues_per_port;
 104         int total_freed = 0;
 105         int total_remaining = 0;
 106         unsigned long flags;
 107         struct octeon_ethernet *priv = netdev_priv(dev);
 108
 109         queues_per_port = cvmx_pko_get_num_queues(priv->port);
 110         /* Drain any pending packets in the free list */
 111         for (qos = 0; qos < queues_per_port; qos++) {
 112                 if (skb_queue_len(&priv->tx_free_list[qos]) == 0)
 113                         continue;
 114                 skb_to_free = cvmx_fau_fetch_and_add32(priv->fau+qos*4,
 115                                                        MAX_SKB_TO_FREE);
 116                 skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free,
 117                                                          priv->fau+qos*4);
 118
 119
 120                 total_freed += skb_to_free;
 121                 if (skb_to_free > 0) {
 122                         struct sk_buff *to_free_list = NULL;
 123
 124                         spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
 125                         while (skb_to_free > 0) {
 126                                 struct sk_buff *t;
 127
 128                                 t = __skb_dequeue(&priv->tx_free_list[qos]);
 129                                 t->next = to_free_list;
 130                                 to_free_list = t;
 131                                 skb_to_free--;
 132                         }
 133                         spin_unlock_irqrestore(&priv->tx_free_list[qos].lock,
 134                                                flags);
 135                         /* Do the actual freeing outside of the lock. */
 136                         while (to_free_list) {
 137                                 struct sk_buff *t = to_free_list;
 138
 139                                 to_free_list = to_free_list->next;
 140                                 dev_kfree_skb_any(t);
 141                         }
 142                 }
 143                 total_remaining += skb_queue_len(&priv->tx_free_list[qos]);
 144         }
 145         if (total_freed >= 0 && netif_queue_stopped(dev))
 146                 netif_wake_queue(dev);
 147         if (total_remaining)
 148                 cvm_oct_kick_tx_poll_watchdog();
 149 }
 150
 151 /**
 152  * cvm_oct_xmit - transmit a packet
 153  * @skb:    Packet to send
 154  * @dev:    Device info structure
 155  *
 156  * Returns Always returns NETDEV_TX_OK
 157  */
 158 int cvm_oct_xmit(struct sk_buff *skb, struct net_device *dev)
 159 {
 160         cvmx_pko_command_word0_t pko_command;
 161         union cvmx_buf_ptr hw_buffer;
 162         uint64_t old_scratch;
 163         uint64_t old_scratch2;
 164         int qos;
 165         int i;
 166         enum {QUEUE_CORE, QUEUE_HW, QUEUE_DROP} queue_type;
 167         struct octeon_ethernet *priv = netdev_priv(dev);
 168         struct sk_buff *to_free_list;
 169         int32_t skb_to_free;
 170         int32_t buffers_to_free;
 171         u32 total_to_clean;
 172         unsigned long flags;
 173 #if REUSE_SKBUFFS_WITHOUT_FREE
 174         unsigned char *fpa_head;
 175 #endif
 176
 177         /*
 178          * Prefetch the private data structure.  It is larger than the
 179          * one cache line.
 180          */
 181         prefetch(priv);
 182
 183         /*
 184          * The check on CVMX_PKO_QUEUES_PER_PORT_* is designed to
 185          * completely remove "qos" in the event neither interface
 186          * supports multiple queues per port.
 187          */
 188         if ((CVMX_PKO_QUEUES_PER_PORT_INTERFACE0 > 1) ||
 189             (CVMX_PKO_QUEUES_PER_PORT_INTERFACE1 > 1)) {
 190                 qos = GET_SKBUFF_QOS(skb);
 191                 if (qos <= 0)
 192                         qos = 0;
 193                 else if (qos >= cvmx_pko_get_num_queues(priv->port))
 194                         qos = 0;
 195         } else
 196                 qos = 0;
 197
 198         if (USE_ASYNC_IOBDMA) {
 199                 /* Save scratch in case userspace is using it */
 200                 CVMX_SYNCIOBDMA;
 201                 old_scratch = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
 202                 old_scratch2 = cvmx_scratch_read64(CVMX_SCR_SCRATCH + 8);
 203
 204                 /*
 205                  * Fetch and increment the number of packets to be
 206                  * freed.
 207                  */
 208                 cvmx_fau_async_fetch_and_add32(CVMX_SCR_SCRATCH + 8,
 209                                                FAU_NUM_PACKET_BUFFERS_TO_FREE,
 210                                                0);
 211                 cvmx_fau_async_fetch_and_add32(CVMX_SCR_SCRATCH,
 212                                                priv->fau + qos * 4,
 213                                                MAX_SKB_TO_FREE);
 214         }
 215
 216         /*
 217          * We have space for 6 segment pointers, If there will be more
 218          * than that, we must linearize.
 219          */
 220         if (unlikely(skb_shinfo(skb)->nr_frags > 5)) {
 221                 if (unlikely(__skb_linearize(skb))) {
 222                         queue_type = QUEUE_DROP;
 223                         if (USE_ASYNC_IOBDMA) {
 224                                 /*
 225                                  * Get the number of skbuffs in use
 226                                  * by the hardware
 227                                  */
 228                                 CVMX_SYNCIOBDMA;
 229                                 skb_to_free =
 230                                         cvmx_scratch_read64(CVMX_SCR_SCRATCH);
 231                         } else {
 232                                 /*
 233                                  * Get the number of skbuffs in use
 234                                  * by the hardware
 235                                  */
 236                                 skb_to_free = cvmx_fau_fetch_and_add32(
 237                                         priv->fau + qos * 4, MAX_SKB_TO_FREE);
 238                         }
 239                         skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free,
 240                                                         priv->fau + qos * 4);
 241                         spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
 242                         goto skip_xmit;
 243                 }
 244         }
 245
 246         /*
 247          * The CN3XXX series of parts has an errata (GMX-401) which
 248          * causes the GMX block to hang if a collision occurs towards
 249          * the end of a <68 byte packet. As a workaround for this, we
 250          * pad packets to be 68 bytes whenever we are in half duplex
 251          * mode. We don't handle the case of having a small packet but
 252          * no room to add the padding.  The kernel should always give
 253          * us at least a cache line
 254          */
 255         if ((skb->len < 64) && OCTEON_IS_MODEL(OCTEON_CN3XXX)) {
 256                 union cvmx_gmxx_prtx_cfg gmx_prt_cfg;
 257                 int interface = INTERFACE(priv->port);
 258                 int index = INDEX(priv->port);
 259
 260                 if (interface < 2) {
 261                         /* We only need to pad packet in half duplex mode */
 262                         gmx_prt_cfg.u64 =
 263                             cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface));
 264                         if (gmx_prt_cfg.s.duplex == 0) {
 265                                 int add_bytes = 64 - skb->len;
 266
 267                                 if ((skb_tail_pointer(skb) + add_bytes) <=
 268                                     skb_end_pointer(skb))
 269                                         memset(__skb_put(skb, add_bytes), 0,
 270                                                add_bytes);
 271                         }
 272                 }
 273         }
 274
 275         /* Build the PKO command */
 276         pko_command.u64 = 0;
 277 #ifdef __LITTLE_ENDIAN
 278         pko_command.s.le = 1;
 279 #endif
 280         pko_command.s.n2 = 1;   /* Don't pollute L2 with the outgoing packet */
 281         pko_command.s.segs = 1;
 282         pko_command.s.total_bytes = skb->len;
 283         pko_command.s.size0 = CVMX_FAU_OP_SIZE_32;
 284         pko_command.s.subone0 = 1;
 285
 286         pko_command.s.dontfree = 1;
 287
 288         /* Build the PKO buffer pointer */
 289         hw_buffer.u64 = 0;
 290         if (skb_shinfo(skb)->nr_frags == 0) {
 291                 hw_buffer.s.addr = XKPHYS_TO_PHYS((u64)skb->data);
 292                 hw_buffer.s.pool = 0;
 293                 hw_buffer.s.size = skb->len;
 294         } else {
 295                 hw_buffer.s.addr = XKPHYS_TO_PHYS((u64)skb->data);
 296                 hw_buffer.s.pool = 0;
 297                 hw_buffer.s.size = skb_headlen(skb);
 298                 CVM_OCT_SKB_CB(skb)[0] = hw_buffer.u64;
 299                 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 300                         struct skb_frag_struct *fs = skb_shinfo(skb)->frags + i;
 301
 302                         hw_buffer.s.addr = XKPHYS_TO_PHYS(
 303                                 (u64)(page_address(fs->page.p) +
 304                                 fs->page_offset));
 305                         hw_buffer.s.size = fs->size;
 306                         CVM_OCT_SKB_CB(skb)[i + 1] = hw_buffer.u64;
 307                 }
 308                 hw_buffer.s.addr = XKPHYS_TO_PHYS((u64)CVM_OCT_SKB_CB(skb));
 309                 hw_buffer.s.size = skb_shinfo(skb)->nr_frags + 1;
 310                 pko_command.s.segs = skb_shinfo(skb)->nr_frags + 1;
 311                 pko_command.s.gather = 1;
 312                 goto dont_put_skbuff_in_hw;
 313         }
 314
 315         /*
 316          * See if we can put this skb in the FPA pool. Any strange
 317          * behavior from the Linux networking stack will most likely
 318          * be caused by a bug in the following code. If some field is
 319          * in use by the network stack and gets carried over when a
 320          * buffer is reused, bad things may happen.  If in doubt and
 321          * you dont need the absolute best performance, disable the
 322          * define REUSE_SKBUFFS_WITHOUT_FREE. The reuse of buffers has
 323          * shown a 25% increase in performance under some loads.
 324          */
 325 #if REUSE_SKBUFFS_WITHOUT_FREE
 326         fpa_head = skb->head + 256 - ((unsigned long)skb->head & 0x7f);
 327         if (unlikely(skb->data < fpa_head)) {
 328                 /*
 329                  * printk("TX buffer beginning can't meet FPA
 330                  * alignment constraints\n");
 331                  */
 332                 goto dont_put_skbuff_in_hw;
 333         }
 334         if (unlikely
 335             ((skb_end_pointer(skb) - fpa_head) < CVMX_FPA_PACKET_POOL_SIZE)) {
 336                 /*
 337                    printk("TX buffer isn't large enough for the FPA\n");
 338                  */
 339                 goto dont_put_skbuff_in_hw;
 340         }
 341         if (unlikely(skb_shared(skb))) {
 342                 /*
 343                    printk("TX buffer sharing data with someone else\n");
 344                  */
 345                 goto dont_put_skbuff_in_hw;
 346         }
 347         if (unlikely(skb_cloned(skb))) {
 348                 /*
 349                    printk("TX buffer has been cloned\n");
 350                  */
 351                 goto dont_put_skbuff_in_hw;
 352         }
 353         if (unlikely(skb_header_cloned(skb))) {
 354                 /*
 355                    printk("TX buffer header has been cloned\n");
 356                  */
 357                 goto dont_put_skbuff_in_hw;
 358         }
 359         if (unlikely(skb->destructor)) {
 360                 /*
 361                    printk("TX buffer has a destructor\n");
 362                  */
 363                 goto dont_put_skbuff_in_hw;
 364         }
 365         if (unlikely(skb_shinfo(skb)->nr_frags)) {
 366                 /*
 367                    printk("TX buffer has fragments\n");
 368                  */
 369                 goto dont_put_skbuff_in_hw;
 370         }
 371         if (unlikely
 372             (skb->truesize !=
 373              sizeof(*skb) + skb_end_offset(skb))) {
 374                 /*
 375                    printk("TX buffer truesize has been changed\n");
 376                  */
 377                 goto dont_put_skbuff_in_hw;
 378         }
 379
 380         /*
 381          * We can use this buffer in the FPA.  We don't need the FAU
 382          * update anymore
 383          */
 384         pko_command.s.dontfree = 0;
 385
 386         hw_buffer.s.back = ((unsigned long)skb->data >> 7) -
 387                            ((unsigned long)fpa_head >> 7);
 388
 389         *(struct sk_buff **)(fpa_head - sizeof(void *)) = skb;
 390
 391         /*
 392          * The skbuff will be reused without ever being freed. We must
 393          * cleanup a bunch of core things.
 394          */
 395         dst_release(skb_dst(skb));
 396         skb_dst_set(skb, NULL);
 397 #ifdef CONFIG_XFRM
 398         secpath_put(skb->sp);
 399         skb->sp = NULL;
 400 #endif
 401         nf_reset(skb);
 402
 403 #ifdef CONFIG_NET_SCHED
 404         skb->tc_index = 0;
 405 #ifdef CONFIG_NET_CLS_ACT
 406         skb->tc_verd = 0;
 407 #endif /* CONFIG_NET_CLS_ACT */
 408 #endif /* CONFIG_NET_SCHED */
 409 #endif /* REUSE_SKBUFFS_WITHOUT_FREE */
 410
 411 dont_put_skbuff_in_hw:
 412
 413         /* Check if we can use the hardware checksumming */
 414         if (USE_HW_TCPUDP_CHECKSUM && (skb->protocol == htons(ETH_P_IP)) &&
 415             (ip_hdr(skb)->version == 4) && (ip_hdr(skb)->ihl == 5) &&
 416             ((ip_hdr(skb)->frag_off == 0) || (ip_hdr(skb)->frag_off == htons(1 << 14)))
 417             && ((ip_hdr(skb)->protocol == IPPROTO_TCP)
 418                 || (ip_hdr(skb)->protocol == IPPROTO_UDP))) {
 419                 /* Use hardware checksum calc */
 420                 pko_command.s.ipoffp1 = sizeof(struct ethhdr) + 1;
 421         }
 422
 423         if (USE_ASYNC_IOBDMA) {
 424                 /* Get the number of skbuffs in use by the hardware */
 425                 CVMX_SYNCIOBDMA;
 426                 skb_to_free = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
 427                 buffers_to_free = cvmx_scratch_read64(CVMX_SCR_SCRATCH + 8);
 428         } else {
 429                 /* Get the number of skbuffs in use by the hardware */
 430                 skb_to_free = cvmx_fau_fetch_and_add32(priv->fau + qos * 4,
 431                                                        MAX_SKB_TO_FREE);
 432                 buffers_to_free =
 433                     cvmx_fau_fetch_and_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, 0);
 434         }
 435
 436         skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free, priv->fau+qos*4);
 437
 438         /*
 439          * If we're sending faster than the receive can free them then
 440          * don't do the HW free.
 441          */
 442         if ((buffers_to_free < -100) && !pko_command.s.dontfree)
 443                 pko_command.s.dontfree = 1;
 444
 445         if (pko_command.s.dontfree) {
 446                 queue_type = QUEUE_CORE;
 447                 pko_command.s.reg0 = priv->fau+qos*4;
 448         } else {
 449                 queue_type = QUEUE_HW;
 450         }
 451         if (USE_ASYNC_IOBDMA)
 452                 cvmx_fau_async_fetch_and_add32(
 453                                 CVMX_SCR_SCRATCH, FAU_TOTAL_TX_TO_CLEAN, 1);
 454
 455         spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
 456
 457         /* Drop this packet if we have too many already queued to the HW */
 458         if (unlikely(skb_queue_len(&priv->tx_free_list[qos]) >=
 459                      MAX_OUT_QUEUE_DEPTH)) {
 460
 461                 if (dev->tx_queue_len != 0) {
 462                         /* Drop the lock when notifying the core.  */
 463                         spin_unlock_irqrestore(&priv->tx_free_list[qos].lock,
 464                                                flags);
 465                         netif_stop_queue(dev);
 466                         spin_lock_irqsave(&priv->tx_free_list[qos].lock,
 467                                           flags);
 468                 } else {
 469                         /* If not using normal queueing.  */
 470                         queue_type = QUEUE_DROP;
 471                         goto skip_xmit;
 472                 }
 473         }
 474
 475         cvmx_pko_send_packet_prepare(priv->port, priv->queue + qos,
 476                                      CVMX_PKO_LOCK_NONE);
 477
 478         /* Send the packet to the output queue */
 479         if (unlikely(cvmx_pko_send_packet_finish(priv->port,
 480                                                  priv->queue + qos,
 481                                                  pko_command, hw_buffer,
 482                                                  CVMX_PKO_LOCK_NONE))) {
 483                 printk_ratelimited("%s: Failed to send the packet\n",
 484                                    dev->name);
 485                 queue_type = QUEUE_DROP;
 486         }
 487 skip_xmit:
 488         to_free_list = NULL;
 489
 490         switch (queue_type) {
 491         case QUEUE_DROP:
 492                 skb->next = to_free_list;
 493                 to_free_list = skb;
 494                 priv->stats.tx_dropped++;
 495                 break;
 496         case QUEUE_HW:
 497                 cvmx_fau_atomic_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, -1);
 498                 break;
 499         case QUEUE_CORE:
 500                 __skb_queue_tail(&priv->tx_free_list[qos], skb);
 501                 break;
 502         default:
 503                 BUG();
 504         }
 505
 506         while (skb_to_free > 0) {
 507                 struct sk_buff *t = __skb_dequeue(&priv->tx_free_list[qos]);
 508
 509                 t->next = to_free_list;
 510                 to_free_list = t;
 511                 skb_to_free--;
 512         }
 513
 514         spin_unlock_irqrestore(&priv->tx_free_list[qos].lock, flags);
 515
 516         /* Do the actual freeing outside of the lock. */
 517         while (to_free_list) {
 518                 struct sk_buff *t = to_free_list;
 519
 520                 to_free_list = to_free_list->next;
 521                 dev_kfree_skb_any(t);
 522         }
 523
 524         if (USE_ASYNC_IOBDMA) {
 525                 CVMX_SYNCIOBDMA;
 526                 total_to_clean = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
 527                 /* Restore the scratch area */
 528                 cvmx_scratch_write64(CVMX_SCR_SCRATCH, old_scratch);
 529                 cvmx_scratch_write64(CVMX_SCR_SCRATCH + 8, old_scratch2);
 530         } else {
 531                 total_to_clean = cvmx_fau_fetch_and_add32(
 532                                                 FAU_TOTAL_TX_TO_CLEAN, 1);
 533         }
 534
 535         if (total_to_clean & 0x3ff) {
 536                 /*
 537                  * Schedule the cleanup tasklet every 1024 packets for
 538                  * the pathological case of high traffic on one port
 539                  * delaying clean up of packets on a different port
 540                  * that is blocked waiting for the cleanup.
 541                  */
 542                 tasklet_schedule(&cvm_oct_tx_cleanup_tasklet);
 543         }
 544
 545         cvm_oct_kick_tx_poll_watchdog();
 546
 547         return NETDEV_TX_OK;
 548 }
 549
 550 /**
 551  * cvm_oct_xmit_pow - transmit a packet to the POW
 552  * @skb:    Packet to send
 553  * @dev:    Device info structure
 554
 555  * Returns Always returns zero
 556  */
 557 int cvm_oct_xmit_pow(struct sk_buff *skb, struct net_device *dev)
 558 {
 559         struct octeon_ethernet *priv = netdev_priv(dev);
 560         void *packet_buffer;
 561         void *copy_location;
 562
 563         /* Get a work queue entry */
 564         cvmx_wqe_t *work = cvmx_fpa_alloc(CVMX_FPA_WQE_POOL);
 565
 566         if (unlikely(work == NULL)) {
 567                 printk_ratelimited("%s: Failed to allocate a work queue entry\n",
 568                                    dev->name);
 569                 priv->stats.tx_dropped++;
 570                 dev_kfree_skb_any(skb);
 571                 return 0;
 572         }
 573
 574         /* Get a packet buffer */
 575         packet_buffer = cvmx_fpa_alloc(CVMX_FPA_PACKET_POOL);
 576         if (unlikely(packet_buffer == NULL)) {
 577                 printk_ratelimited("%s: Failed to allocate a packet buffer\n",
 578                                    dev->name);
 579                 cvmx_fpa_free(work, CVMX_FPA_WQE_POOL, DONT_WRITEBACK(1));
 580                 priv->stats.tx_dropped++;
 581                 dev_kfree_skb_any(skb);
 582                 return 0;
 583         }
 584
 585         /*
 586          * Calculate where we need to copy the data to. We need to
 587          * leave 8 bytes for a next pointer (unused). We also need to
 588          * include any configure skip. Then we need to align the IP
 589          * packet src and dest into the same 64bit word. The below
 590          * calculation may add a little extra, but that doesn't
 591          * hurt.
 592          */
 593         copy_location = packet_buffer + sizeof(uint64_t);
 594         copy_location += ((CVMX_HELPER_FIRST_MBUFF_SKIP + 7) & 0xfff8) + 6;
 595
 596         /*
 597          * We have to copy the packet since whoever processes this
 598          * packet will free it to a hardware pool. We can't use the
 599          * trick of counting outstanding packets like in
 600          * cvm_oct_xmit.
 601          */
 602         memcpy(copy_location, skb->data, skb->len);
 603
 604         /*
 605          * Fill in some of the work queue fields. We may need to add
 606          * more if the software at the other end needs them.
 607          */
 608         work->hw_chksum = skb->csum;
 609         work->len = skb->len;
 610         work->ipprt = priv->port;
 611         work->qos = priv->port & 0x7;
 612         work->grp = pow_send_group;
 613         work->tag_type = CVMX_HELPER_INPUT_TAG_TYPE;
 614         work->tag = pow_send_group;     /* FIXME */
 615         /* Default to zero. Sets of zero later are commented out */
 616         work->word2.u64 = 0;
 617         work->word2.s.bufs = 1;
 618         work->packet_ptr.u64 = 0;
 619         work->packet_ptr.s.addr = cvmx_ptr_to_phys(copy_location);
 620         work->packet_ptr.s.pool = CVMX_FPA_PACKET_POOL;
 621         work->packet_ptr.s.size = CVMX_FPA_PACKET_POOL_SIZE;
 622         work->packet_ptr.s.back = (copy_location - packet_buffer) >> 7;
 623
 624         if (skb->protocol == htons(ETH_P_IP)) {
 625                 work->word2.s.ip_offset = 14;
 626 #if 0
 627                 work->word2.s.vlan_valid = 0;   /* FIXME */
 628                 work->word2.s.vlan_cfi = 0;     /* FIXME */
 629                 work->word2.s.vlan_id = 0;      /* FIXME */
 630                 work->word2.s.dec_ipcomp = 0;   /* FIXME */
 631 #endif
 632                 work->word2.s.tcp_or_udp =
 633                     (ip_hdr(skb)->protocol == IPPROTO_TCP)
 634                     || (ip_hdr(skb)->protocol == IPPROTO_UDP);
 635 #if 0
 636                 /* FIXME */
 637                 work->word2.s.dec_ipsec = 0;
 638                 /* We only support IPv4 right now */
 639                 work->word2.s.is_v6 = 0;
 640                 /* Hardware would set to zero */
 641                 work->word2.s.software = 0;
 642                 /* No error, packet is internal */
 643                 work->word2.s.L4_error = 0;
 644 #endif
 645                 work->word2.s.is_frag = !((ip_hdr(skb)->frag_off == 0)
 646                                           || (ip_hdr(skb)->frag_off ==
 647                                               1 << 14));
 648 #if 0
 649                 /* Assume Linux is sending a good packet */
 650                 work->word2.s.IP_exc = 0;
 651 #endif
 652                 work->word2.s.is_bcast = (skb->pkt_type == PACKET_BROADCAST);
 653                 work->word2.s.is_mcast = (skb->pkt_type == PACKET_MULTICAST);
 654 #if 0
 655                 /* This is an IP packet */
 656                 work->word2.s.not_IP = 0;
 657                 /* No error, packet is internal */
 658                 work->word2.s.rcv_error = 0;
 659                 /* No error, packet is internal */
 660                 work->word2.s.err_code = 0;
 661 #endif
 662
 663                 /*
 664                  * When copying the data, include 4 bytes of the
 665                  * ethernet header to align the same way hardware
 666                  * does.
 667                  */
 668                 memcpy(work->packet_data, skb->data + 10,
 669                        sizeof(work->packet_data));
 670         } else {
 671 #if 0
 672                 work->word2.snoip.vlan_valid = 0;       /* FIXME */
 673                 work->word2.snoip.vlan_cfi = 0; /* FIXME */
 674                 work->word2.snoip.vlan_id = 0;  /* FIXME */
 675                 work->word2.snoip.software = 0; /* Hardware would set to zero */
 676 #endif
 677                 work->word2.snoip.is_rarp = skb->protocol == htons(ETH_P_RARP);
 678                 work->word2.snoip.is_arp = skb->protocol == htons(ETH_P_ARP);
 679                 work->word2.snoip.is_bcast =
 680                     (skb->pkt_type == PACKET_BROADCAST);
 681                 work->word2.snoip.is_mcast =
 682                     (skb->pkt_type == PACKET_MULTICAST);
 683                 work->word2.snoip.not_IP = 1;   /* IP was done up above */
 684 #if 0
 685                 /* No error, packet is internal */
 686                 work->word2.snoip.rcv_error = 0;
 687                 /* No error, packet is internal */
 688                 work->word2.snoip.err_code = 0;
 689 #endif
 690                 memcpy(work->packet_data, skb->data, sizeof(work->packet_data));
 691         }
 692
 693         /* Submit the packet to the POW */
 694         cvmx_pow_work_submit(work, work->tag, work->tag_type, work->qos,
 695                              work->grp);
 696         priv->stats.tx_packets++;
 697         priv->stats.tx_bytes += skb->len;
 698         dev_consume_skb_any(skb);
 699         return 0;
 700 }
 701
 702 /**
 703  * cvm_oct_tx_shutdown_dev - free all skb that are currently queued for TX.
 704  * @dev:    Device being shutdown
 705  *
 706  */
 707 void cvm_oct_tx_shutdown_dev(struct net_device *dev)
 708 {
 709         struct octeon_ethernet *priv = netdev_priv(dev);
 710         unsigned long flags;
 711         int qos;
 712
 713         for (qos = 0; qos < 16; qos++) {
 714                 spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
 715                 while (skb_queue_len(&priv->tx_free_list[qos]))
 716                         dev_kfree_skb_any(__skb_dequeue
 717                                           (&priv->tx_free_list[qos]));
 718                 spin_unlock_irqrestore(&priv->tx_free_list[qos].lock, flags);
 719         }
 720 }
 721
 722 static void cvm_oct_tx_do_cleanup(unsigned long arg)
 723 {
 724         int port;
 725
 726         for (port = 0; port < TOTAL_NUMBER_OF_PORTS; port++) {
 727                 if (cvm_oct_device[port]) {
 728                         struct net_device *dev = cvm_oct_device[port];
 729
 730                         cvm_oct_free_tx_skbs(dev);
 731                 }
 732         }
 733 }
 734
 735 static irqreturn_t cvm_oct_tx_cleanup_watchdog(int cpl, void *dev_id)
 736 {
 737         /* Disable the interrupt.  */
 738         cvmx_write_csr(CVMX_CIU_TIMX(1), 0);
 739         /* Do the work in the tasklet.  */
 740         tasklet_schedule(&cvm_oct_tx_cleanup_tasklet);
 741         return IRQ_HANDLED;
 742 }
 743
 744 void cvm_oct_tx_initialize(void)
 745 {
 746         int i;
 747
 748         /* Disable the interrupt.  */
 749         cvmx_write_csr(CVMX_CIU_TIMX(1), 0);
 750         /* Register an IRQ handler to receive CIU_TIMX(1) interrupts */
 751         i = request_irq(OCTEON_IRQ_TIMER1,
 752                         cvm_oct_tx_cleanup_watchdog, 0,
 753                         "Ethernet", cvm_oct_device);
 754
 755         if (i)
 756                 panic("Could not acquire Ethernet IRQ %d\n", OCTEON_IRQ_TIMER1);
 757 }
 758
 759 void cvm_oct_tx_shutdown(void)
 760 {
 761         /* Free the interrupt handler */
 762         free_irq(OCTEON_IRQ_TIMER1, cvm_oct_device);
 763 }