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