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