1 /* 2 * This file is part of wl1251 3 * 4 * Copyright (c) 1998-2007 Texas Instruments Incorporated 5 * Copyright (C) 2008 Nokia Corporation 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * version 2 as published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, but 12 * WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 19 * 02110-1301 USA 20 * 21 */ 22 23 #include <linux/kernel.h> 24 #include <linux/module.h> 25 26 #include "wl1251.h" 27 #include "reg.h" 28 #include "tx.h" 29 #include "ps.h" 30 #include "io.h" 31 32 static bool wl1251_tx_double_buffer_busy(struct wl1251 *wl, u32 data_out_count) 33 { 34 int used, data_in_count; 35 36 data_in_count = wl->data_in_count; 37 38 if (data_in_count < data_out_count) 39 /* data_in_count has wrapped */ 40 data_in_count += TX_STATUS_DATA_OUT_COUNT_MASK + 1; 41 42 used = data_in_count - data_out_count; 43 44 WARN_ON(used < 0); 45 WARN_ON(used > DP_TX_PACKET_RING_CHUNK_NUM); 46 47 if (used >= DP_TX_PACKET_RING_CHUNK_NUM) 48 return true; 49 else 50 return false; 51 } 52 53 static int wl1251_tx_path_status(struct wl1251 *wl) 54 { 55 u32 status, addr, data_out_count; 56 bool busy; 57 58 addr = wl->data_path->tx_control_addr; 59 status = wl1251_mem_read32(wl, addr); 60 data_out_count = status & TX_STATUS_DATA_OUT_COUNT_MASK; 61 busy = wl1251_tx_double_buffer_busy(wl, data_out_count); 62 63 if (busy) 64 return -EBUSY; 65 66 return 0; 67 } 68 69 static int wl1251_tx_id(struct wl1251 *wl, struct sk_buff *skb) 70 { 71 int i; 72 73 for (i = 0; i < FW_TX_CMPLT_BLOCK_SIZE; i++) 74 if (wl->tx_frames[i] == NULL) { 75 wl->tx_frames[i] = skb; 76 return i; 77 } 78 79 return -EBUSY; 80 } 81 82 static void wl1251_tx_control(struct tx_double_buffer_desc *tx_hdr, 83 struct ieee80211_tx_info *control, u16 fc) 84 { 85 *(u16 *)&tx_hdr->control = 0; 86 87 tx_hdr->control.rate_policy = 0; 88 89 /* 802.11 packets */ 90 tx_hdr->control.packet_type = 0; 91 92 if (control->flags & IEEE80211_TX_CTL_NO_ACK) 93 tx_hdr->control.ack_policy = 1; 94 95 tx_hdr->control.tx_complete = 1; 96 97 if ((fc & IEEE80211_FTYPE_DATA) && 98 ((fc & IEEE80211_STYPE_QOS_DATA) || 99 (fc & IEEE80211_STYPE_QOS_NULLFUNC))) 100 tx_hdr->control.qos = 1; 101 } 102 103 /* RSN + MIC = 8 + 8 = 16 bytes (worst case - AES). */ 104 #define MAX_MSDU_SECURITY_LENGTH 16 105 #define MAX_MPDU_SECURITY_LENGTH 16 106 #define WLAN_QOS_HDR_LEN 26 107 #define MAX_MPDU_HEADER_AND_SECURITY (MAX_MPDU_SECURITY_LENGTH + \ 108 WLAN_QOS_HDR_LEN) 109 #define HW_BLOCK_SIZE 252 110 static void wl1251_tx_frag_block_num(struct tx_double_buffer_desc *tx_hdr) 111 { 112 u16 payload_len, frag_threshold, mem_blocks; 113 u16 num_mpdus, mem_blocks_per_frag; 114 115 frag_threshold = IEEE80211_MAX_FRAG_THRESHOLD; 116 tx_hdr->frag_threshold = cpu_to_le16(frag_threshold); 117 118 payload_len = le16_to_cpu(tx_hdr->length) + MAX_MSDU_SECURITY_LENGTH; 119 120 if (payload_len > frag_threshold) { 121 mem_blocks_per_frag = 122 ((frag_threshold + MAX_MPDU_HEADER_AND_SECURITY) / 123 HW_BLOCK_SIZE) + 1; 124 num_mpdus = payload_len / frag_threshold; 125 mem_blocks = num_mpdus * mem_blocks_per_frag; 126 payload_len -= num_mpdus * frag_threshold; 127 num_mpdus++; 128 129 } else { 130 mem_blocks_per_frag = 0; 131 mem_blocks = 0; 132 num_mpdus = 1; 133 } 134 135 mem_blocks += (payload_len / HW_BLOCK_SIZE) + 1; 136 137 if (num_mpdus > 1) 138 mem_blocks += min(num_mpdus, mem_blocks_per_frag); 139 140 tx_hdr->num_mem_blocks = mem_blocks; 141 } 142 143 static int wl1251_tx_fill_hdr(struct wl1251 *wl, struct sk_buff *skb, 144 struct ieee80211_tx_info *control) 145 { 146 struct tx_double_buffer_desc *tx_hdr; 147 struct ieee80211_rate *rate; 148 int id; 149 u16 fc; 150 151 if (!skb) 152 return -EINVAL; 153 154 id = wl1251_tx_id(wl, skb); 155 if (id < 0) 156 return id; 157 158 fc = *(u16 *)skb->data; 159 tx_hdr = (struct tx_double_buffer_desc *) skb_push(skb, 160 sizeof(*tx_hdr)); 161 162 tx_hdr->length = cpu_to_le16(skb->len - sizeof(*tx_hdr)); 163 rate = ieee80211_get_tx_rate(wl->hw, control); 164 tx_hdr->rate = cpu_to_le16(rate->hw_value); 165 tx_hdr->expiry_time = cpu_to_le32(1 << 16); 166 tx_hdr->id = id; 167 168 tx_hdr->xmit_queue = wl1251_tx_get_queue(skb_get_queue_mapping(skb)); 169 170 wl1251_tx_control(tx_hdr, control, fc); 171 wl1251_tx_frag_block_num(tx_hdr); 172 173 return 0; 174 } 175 176 /* We copy the packet to the target */ 177 static int wl1251_tx_send_packet(struct wl1251 *wl, struct sk_buff *skb, 178 struct ieee80211_tx_info *control) 179 { 180 struct tx_double_buffer_desc *tx_hdr; 181 int len; 182 u32 addr; 183 184 if (!skb) 185 return -EINVAL; 186 187 tx_hdr = (struct tx_double_buffer_desc *) skb->data; 188 189 if (control->control.hw_key && 190 control->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP) { 191 int hdrlen; 192 __le16 fc; 193 u16 length; 194 u8 *pos; 195 196 fc = *(__le16 *)(skb->data + sizeof(*tx_hdr)); 197 length = le16_to_cpu(tx_hdr->length) + WL1251_TKIP_IV_SPACE; 198 tx_hdr->length = cpu_to_le16(length); 199 200 hdrlen = ieee80211_hdrlen(fc); 201 202 pos = skb_push(skb, WL1251_TKIP_IV_SPACE); 203 memmove(pos, pos + WL1251_TKIP_IV_SPACE, 204 sizeof(*tx_hdr) + hdrlen); 205 } 206 207 /* Revisit. This is a workaround for getting non-aligned packets. 208 This happens at least with EAPOL packets from the user space. 209 Our DMA requires packets to be aligned on a 4-byte boundary. 210 */ 211 if (unlikely((long)skb->data & 0x03)) { 212 int offset = (4 - (long)skb->data) & 0x03; 213 wl1251_debug(DEBUG_TX, "skb offset %d", offset); 214 215 /* check whether the current skb can be used */ 216 if (skb_cloned(skb) || (skb_tailroom(skb) < offset)) { 217 struct sk_buff *newskb = skb_copy_expand(skb, 0, 3, 218 GFP_KERNEL); 219 220 if (unlikely(newskb == NULL)) { 221 wl1251_error("Can't allocate skb!"); 222 return -EINVAL; 223 } 224 225 tx_hdr = (struct tx_double_buffer_desc *) newskb->data; 226 227 dev_kfree_skb_any(skb); 228 wl->tx_frames[tx_hdr->id] = skb = newskb; 229 230 offset = (4 - (long)skb->data) & 0x03; 231 wl1251_debug(DEBUG_TX, "new skb offset %d", offset); 232 } 233 234 /* align the buffer on a 4-byte boundary */ 235 if (offset) { 236 unsigned char *src = skb->data; 237 skb_reserve(skb, offset); 238 memmove(skb->data, src, skb->len); 239 tx_hdr = (struct tx_double_buffer_desc *) skb->data; 240 } 241 } 242 243 /* Our skb->data at this point includes the HW header */ 244 len = WL1251_TX_ALIGN(skb->len); 245 246 if (wl->data_in_count & 0x1) 247 addr = wl->data_path->tx_packet_ring_addr + 248 wl->data_path->tx_packet_ring_chunk_size; 249 else 250 addr = wl->data_path->tx_packet_ring_addr; 251 252 wl1251_mem_write(wl, addr, skb->data, len); 253 254 wl1251_debug(DEBUG_TX, "tx id %u skb 0x%p payload %u rate 0x%x " 255 "queue %d", tx_hdr->id, skb, tx_hdr->length, 256 tx_hdr->rate, tx_hdr->xmit_queue); 257 258 return 0; 259 } 260 261 static void wl1251_tx_trigger(struct wl1251 *wl) 262 { 263 u32 data, addr; 264 265 if (wl->data_in_count & 0x1) { 266 addr = ACX_REG_INTERRUPT_TRIG_H; 267 data = INTR_TRIG_TX_PROC1; 268 } else { 269 addr = ACX_REG_INTERRUPT_TRIG; 270 data = INTR_TRIG_TX_PROC0; 271 } 272 273 wl1251_reg_write32(wl, addr, data); 274 275 /* Bumping data in */ 276 wl->data_in_count = (wl->data_in_count + 1) & 277 TX_STATUS_DATA_OUT_COUNT_MASK; 278 } 279 280 /* caller must hold wl->mutex */ 281 static int wl1251_tx_frame(struct wl1251 *wl, struct sk_buff *skb) 282 { 283 struct ieee80211_tx_info *info; 284 int ret = 0; 285 u8 idx; 286 287 info = IEEE80211_SKB_CB(skb); 288 289 if (info->control.hw_key) { 290 idx = info->control.hw_key->hw_key_idx; 291 if (unlikely(wl->default_key != idx)) { 292 ret = wl1251_acx_default_key(wl, idx); 293 if (ret < 0) 294 return ret; 295 } 296 } 297 298 ret = wl1251_tx_path_status(wl); 299 if (ret < 0) 300 return ret; 301 302 ret = wl1251_tx_fill_hdr(wl, skb, info); 303 if (ret < 0) 304 return ret; 305 306 ret = wl1251_tx_send_packet(wl, skb, info); 307 if (ret < 0) 308 return ret; 309 310 wl1251_tx_trigger(wl); 311 312 return ret; 313 } 314 315 void wl1251_tx_work(struct work_struct *work) 316 { 317 struct wl1251 *wl = container_of(work, struct wl1251, tx_work); 318 struct sk_buff *skb; 319 bool woken_up = false; 320 int ret; 321 322 mutex_lock(&wl->mutex); 323 324 if (unlikely(wl->state == WL1251_STATE_OFF)) 325 goto out; 326 327 while ((skb = skb_dequeue(&wl->tx_queue))) { 328 if (!woken_up) { 329 ret = wl1251_ps_elp_wakeup(wl); 330 if (ret < 0) 331 goto out; 332 woken_up = true; 333 } 334 335 ret = wl1251_tx_frame(wl, skb); 336 if (ret == -EBUSY) { 337 skb_queue_head(&wl->tx_queue, skb); 338 goto out; 339 } else if (ret < 0) { 340 dev_kfree_skb(skb); 341 goto out; 342 } 343 } 344 345 out: 346 if (woken_up) 347 wl1251_ps_elp_sleep(wl); 348 349 mutex_unlock(&wl->mutex); 350 } 351 352 static const char *wl1251_tx_parse_status(u8 status) 353 { 354 /* 8 bit status field, one character per bit plus null */ 355 static char buf[9]; 356 int i = 0; 357 358 memset(buf, 0, sizeof(buf)); 359 360 if (status & TX_DMA_ERROR) 361 buf[i++] = 'm'; 362 if (status & TX_DISABLED) 363 buf[i++] = 'd'; 364 if (status & TX_RETRY_EXCEEDED) 365 buf[i++] = 'r'; 366 if (status & TX_TIMEOUT) 367 buf[i++] = 't'; 368 if (status & TX_KEY_NOT_FOUND) 369 buf[i++] = 'k'; 370 if (status & TX_ENCRYPT_FAIL) 371 buf[i++] = 'e'; 372 if (status & TX_UNAVAILABLE_PRIORITY) 373 buf[i++] = 'p'; 374 375 /* bit 0 is unused apparently */ 376 377 return buf; 378 } 379 380 static void wl1251_tx_packet_cb(struct wl1251 *wl, 381 struct tx_result *result) 382 { 383 struct ieee80211_tx_info *info; 384 struct sk_buff *skb; 385 int hdrlen; 386 u8 *frame; 387 388 skb = wl->tx_frames[result->id]; 389 if (skb == NULL) { 390 wl1251_error("SKB for packet %d is NULL", result->id); 391 return; 392 } 393 394 info = IEEE80211_SKB_CB(skb); 395 396 if (!(info->flags & IEEE80211_TX_CTL_NO_ACK) && 397 (result->status == TX_SUCCESS)) 398 info->flags |= IEEE80211_TX_STAT_ACK; 399 400 info->status.rates[0].count = result->ack_failures + 1; 401 wl->stats.retry_count += result->ack_failures; 402 403 /* 404 * We have to remove our private TX header before pushing 405 * the skb back to mac80211. 406 */ 407 frame = skb_pull(skb, sizeof(struct tx_double_buffer_desc)); 408 if (info->control.hw_key && 409 info->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP) { 410 hdrlen = ieee80211_get_hdrlen_from_skb(skb); 411 memmove(frame + WL1251_TKIP_IV_SPACE, frame, hdrlen); 412 skb_pull(skb, WL1251_TKIP_IV_SPACE); 413 } 414 415 wl1251_debug(DEBUG_TX, "tx status id %u skb 0x%p failures %u rate 0x%x" 416 " status 0x%x (%s)", 417 result->id, skb, result->ack_failures, result->rate, 418 result->status, wl1251_tx_parse_status(result->status)); 419 420 421 ieee80211_tx_status(wl->hw, skb); 422 423 wl->tx_frames[result->id] = NULL; 424 } 425 426 /* Called upon reception of a TX complete interrupt */ 427 void wl1251_tx_complete(struct wl1251 *wl) 428 { 429 int i, result_index, num_complete = 0, queue_len; 430 struct tx_result result[FW_TX_CMPLT_BLOCK_SIZE], *result_ptr; 431 unsigned long flags; 432 433 if (unlikely(wl->state != WL1251_STATE_ON)) 434 return; 435 436 /* First we read the result */ 437 wl1251_mem_read(wl, wl->data_path->tx_complete_addr, 438 result, sizeof(result)); 439 440 result_index = wl->next_tx_complete; 441 442 for (i = 0; i < ARRAY_SIZE(result); i++) { 443 result_ptr = &result[result_index]; 444 445 if (result_ptr->done_1 == 1 && 446 result_ptr->done_2 == 1) { 447 wl1251_tx_packet_cb(wl, result_ptr); 448 449 result_ptr->done_1 = 0; 450 result_ptr->done_2 = 0; 451 452 result_index = (result_index + 1) & 453 (FW_TX_CMPLT_BLOCK_SIZE - 1); 454 num_complete++; 455 } else { 456 break; 457 } 458 } 459 460 queue_len = skb_queue_len(&wl->tx_queue); 461 462 if ((num_complete > 0) && (queue_len > 0)) { 463 /* firmware buffer has space, reschedule tx_work */ 464 wl1251_debug(DEBUG_TX, "tx_complete: reschedule tx_work"); 465 ieee80211_queue_work(wl->hw, &wl->tx_work); 466 } 467 468 if (wl->tx_queue_stopped && 469 queue_len <= WL1251_TX_QUEUE_LOW_WATERMARK) { 470 /* tx_queue has space, restart queues */ 471 wl1251_debug(DEBUG_TX, "tx_complete: waking queues"); 472 spin_lock_irqsave(&wl->wl_lock, flags); 473 ieee80211_wake_queues(wl->hw); 474 wl->tx_queue_stopped = false; 475 spin_unlock_irqrestore(&wl->wl_lock, flags); 476 } 477 478 /* Every completed frame needs to be acknowledged */ 479 if (num_complete) { 480 /* 481 * If we've wrapped, we have to clear 482 * the results in 2 steps. 483 */ 484 if (result_index > wl->next_tx_complete) { 485 /* Only 1 write is needed */ 486 wl1251_mem_write(wl, 487 wl->data_path->tx_complete_addr + 488 (wl->next_tx_complete * 489 sizeof(struct tx_result)), 490 &result[wl->next_tx_complete], 491 num_complete * 492 sizeof(struct tx_result)); 493 494 495 } else if (result_index < wl->next_tx_complete) { 496 /* 2 writes are needed */ 497 wl1251_mem_write(wl, 498 wl->data_path->tx_complete_addr + 499 (wl->next_tx_complete * 500 sizeof(struct tx_result)), 501 &result[wl->next_tx_complete], 502 (FW_TX_CMPLT_BLOCK_SIZE - 503 wl->next_tx_complete) * 504 sizeof(struct tx_result)); 505 506 wl1251_mem_write(wl, 507 wl->data_path->tx_complete_addr, 508 result, 509 (num_complete - 510 FW_TX_CMPLT_BLOCK_SIZE + 511 wl->next_tx_complete) * 512 sizeof(struct tx_result)); 513 514 } else { 515 /* We have to write the whole array */ 516 wl1251_mem_write(wl, 517 wl->data_path->tx_complete_addr, 518 result, 519 FW_TX_CMPLT_BLOCK_SIZE * 520 sizeof(struct tx_result)); 521 } 522 523 } 524 525 wl->next_tx_complete = result_index; 526 } 527 528 /* caller must hold wl->mutex */ 529 void wl1251_tx_flush(struct wl1251 *wl) 530 { 531 int i; 532 struct sk_buff *skb; 533 struct ieee80211_tx_info *info; 534 535 /* TX failure */ 536 /* control->flags = 0; FIXME */ 537 538 while ((skb = skb_dequeue(&wl->tx_queue))) { 539 info = IEEE80211_SKB_CB(skb); 540 541 wl1251_debug(DEBUG_TX, "flushing skb 0x%p", skb); 542 543 if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) 544 continue; 545 546 ieee80211_tx_status(wl->hw, skb); 547 } 548 549 for (i = 0; i < FW_TX_CMPLT_BLOCK_SIZE; i++) 550 if (wl->tx_frames[i] != NULL) { 551 skb = wl->tx_frames[i]; 552 info = IEEE80211_SKB_CB(skb); 553 554 if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) 555 continue; 556 557 ieee80211_tx_status(wl->hw, skb); 558 wl->tx_frames[i] = NULL; 559 } 560 } 561