tx.c revision 31627dc59b4a87c4198b4245a7de1b8ccf4424fa
1/* 2 * This file is part of wl1271 3 * 4 * Copyright (C) 2009 Nokia Corporation 5 * 6 * Contact: Luciano Coelho <luciano.coelho@nokia.com> 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * version 2 as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, but 13 * WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 20 * 02110-1301 USA 21 * 22 */ 23 24#include <linux/kernel.h> 25#include <linux/module.h> 26 27#include "wl1271.h" 28#include "wl1271_io.h" 29#include "wl1271_reg.h" 30#include "wl1271_ps.h" 31#include "wl1271_tx.h" 32 33static int wl1271_tx_id(struct wl1271 *wl, struct sk_buff *skb) 34{ 35 int i; 36 for (i = 0; i < ACX_TX_DESCRIPTORS; i++) 37 if (wl->tx_frames[i] == NULL) { 38 wl->tx_frames[i] = skb; 39 return i; 40 } 41 42 return -EBUSY; 43} 44 45static int wl1271_tx_allocate(struct wl1271 *wl, struct sk_buff *skb, u32 extra) 46{ 47 struct wl1271_tx_hw_descr *desc; 48 u32 total_len = skb->len + sizeof(struct wl1271_tx_hw_descr) + extra; 49 u32 total_blocks; 50 int id, ret = -EBUSY; 51 52 /* allocate free identifier for the packet */ 53 id = wl1271_tx_id(wl, skb); 54 if (id < 0) 55 return id; 56 57 /* approximate the number of blocks required for this packet 58 in the firmware */ 59 total_blocks = total_len + TX_HW_BLOCK_SIZE - 1; 60 total_blocks = total_blocks / TX_HW_BLOCK_SIZE + TX_HW_BLOCK_SPARE; 61 if (total_blocks <= wl->tx_blocks_available) { 62 desc = (struct wl1271_tx_hw_descr *)skb_push( 63 skb, total_len - skb->len); 64 65 desc->extra_mem_blocks = TX_HW_BLOCK_SPARE; 66 desc->total_mem_blocks = total_blocks; 67 desc->id = id; 68 69 wl->tx_blocks_available -= total_blocks; 70 71 ret = 0; 72 73 wl1271_debug(DEBUG_TX, 74 "tx_allocate: size: %d, blocks: %d, id: %d", 75 total_len, total_blocks, id); 76 } else 77 wl->tx_frames[id] = NULL; 78 79 return ret; 80} 81 82static int wl1271_tx_fill_hdr(struct wl1271 *wl, struct sk_buff *skb, 83 u32 extra, struct ieee80211_tx_info *control) 84{ 85 struct timespec ts; 86 struct wl1271_tx_hw_descr *desc; 87 int pad, ac; 88 s64 hosttime; 89 u16 tx_attr; 90 91 desc = (struct wl1271_tx_hw_descr *) skb->data; 92 93 /* relocate space for security header */ 94 if (extra) { 95 void *framestart = skb->data + sizeof(*desc); 96 u16 fc = *(u16 *)(framestart + extra); 97 int hdrlen = ieee80211_hdrlen(cpu_to_le16(fc)); 98 memmove(framestart, framestart + extra, hdrlen); 99 } 100 101 /* configure packet life time */ 102 getnstimeofday(&ts); 103 hosttime = (timespec_to_ns(&ts) >> 10); 104 desc->start_time = cpu_to_le32(hosttime - wl->time_offset); 105 desc->life_time = cpu_to_le16(TX_HW_MGMT_PKT_LIFETIME_TU); 106 107 /* configure the tx attributes */ 108 tx_attr = wl->session_counter << TX_HW_ATTR_OFST_SESSION_COUNTER; 109 110 /* queue */ 111 ac = wl1271_tx_get_queue(skb_get_queue_mapping(skb)); 112 desc->tid = wl1271_tx_ac_to_tid(ac); 113 114 desc->aid = TX_HW_DEFAULT_AID; 115 desc->reserved = 0; 116 117 /* align the length (and store in terms of words) */ 118 pad = WL1271_TX_ALIGN(skb->len); 119 desc->length = cpu_to_le16(pad >> 2); 120 121 /* calculate number of padding bytes */ 122 pad = pad - skb->len; 123 tx_attr |= pad << TX_HW_ATTR_OFST_LAST_WORD_PAD; 124 125 /* if the packets are destined for AP (have a STA entry) send them 126 with AP rate policies, otherwise use default basic rates */ 127 if (control->control.sta) 128 tx_attr |= ACX_TX_AP_FULL_RATE << TX_HW_ATTR_OFST_RATE_POLICY; 129 130 desc->tx_attr = cpu_to_le16(tx_attr); 131 132 wl1271_debug(DEBUG_TX, "tx_fill_hdr: pad: %d", pad); 133 return 0; 134} 135 136static int wl1271_tx_send_packet(struct wl1271 *wl, struct sk_buff *skb, 137 struct ieee80211_tx_info *control) 138{ 139 140 struct wl1271_tx_hw_descr *desc; 141 int len; 142 143 /* FIXME: This is a workaround for getting non-aligned packets. 144 This happens at least with EAPOL packets from the user space. 145 Our DMA requires packets to be aligned on a 4-byte boundary. 146 */ 147 if (unlikely((long)skb->data & 0x03)) { 148 int offset = (4 - (long)skb->data) & 0x03; 149 wl1271_debug(DEBUG_TX, "skb offset %d", offset); 150 151 /* check whether the current skb can be used */ 152 if (!skb_cloned(skb) && (skb_tailroom(skb) >= offset)) { 153 unsigned char *src = skb->data; 154 155 /* align the buffer on a 4-byte boundary */ 156 skb_reserve(skb, offset); 157 memmove(skb->data, src, skb->len); 158 } else { 159 wl1271_info("No handler, fixme!"); 160 return -EINVAL; 161 } 162 } 163 164 len = WL1271_TX_ALIGN(skb->len); 165 166 /* perform a fixed address block write with the packet */ 167 wl1271_write(wl, WL1271_SLV_MEM_DATA, skb->data, len, true); 168 169 /* write packet new counter into the write access register */ 170 wl->tx_packets_count++; 171 172 desc = (struct wl1271_tx_hw_descr *) skb->data; 173 wl1271_debug(DEBUG_TX, "tx id %u skb 0x%p payload %u (%u words)", 174 desc->id, skb, len, desc->length); 175 176 return 0; 177} 178 179/* caller must hold wl->mutex */ 180static int wl1271_tx_frame(struct wl1271 *wl, struct sk_buff *skb) 181{ 182 struct ieee80211_tx_info *info; 183 u32 extra = 0; 184 int ret = 0; 185 u8 idx; 186 187 if (!skb) 188 return -EINVAL; 189 190 info = IEEE80211_SKB_CB(skb); 191 192 if (info->control.hw_key && 193 info->control.hw_key->alg == ALG_TKIP) 194 extra = WL1271_TKIP_IV_SPACE; 195 196 if (info->control.hw_key) { 197 idx = info->control.hw_key->hw_key_idx; 198 199 /* FIXME: do we have to do this if we're not using WEP? */ 200 if (unlikely(wl->default_key != idx)) { 201 ret = wl1271_cmd_set_default_wep_key(wl, idx); 202 if (ret < 0) 203 return ret; 204 wl->default_key = idx; 205 } 206 } 207 208 ret = wl1271_tx_allocate(wl, skb, extra); 209 if (ret < 0) 210 return ret; 211 212 ret = wl1271_tx_fill_hdr(wl, skb, extra, info); 213 if (ret < 0) 214 return ret; 215 216 ret = wl1271_tx_send_packet(wl, skb, info); 217 if (ret < 0) 218 return ret; 219 220 return ret; 221} 222 223static u32 wl1271_tx_enabled_rates_get(struct wl1271 *wl, u32 rate_set) 224{ 225 struct ieee80211_supported_band *band; 226 u32 enabled_rates = 0; 227 int bit; 228 229 band = wl->hw->wiphy->bands[wl->band]; 230 for (bit = 0; bit < band->n_bitrates; bit++) { 231 if (rate_set & 0x1) 232 enabled_rates |= band->bitrates[bit].hw_value; 233 rate_set >>= 1; 234 } 235 236 return enabled_rates; 237} 238 239void wl1271_tx_work(struct work_struct *work) 240{ 241 struct wl1271 *wl = container_of(work, struct wl1271, tx_work); 242 struct sk_buff *skb; 243 bool woken_up = false; 244 u32 sta_rates = 0; 245 u32 prev_tx_packets_count; 246 int ret; 247 248 /* check if the rates supported by the AP have changed */ 249 if (unlikely(test_and_clear_bit(WL1271_FLAG_STA_RATES_CHANGED, 250 &wl->flags))) { 251 unsigned long flags; 252 spin_lock_irqsave(&wl->wl_lock, flags); 253 sta_rates = wl->sta_rate_set; 254 spin_unlock_irqrestore(&wl->wl_lock, flags); 255 } 256 257 mutex_lock(&wl->mutex); 258 259 if (unlikely(wl->state == WL1271_STATE_OFF)) 260 goto out; 261 262 prev_tx_packets_count = wl->tx_packets_count; 263 264 /* if rates have changed, re-configure the rate policy */ 265 if (unlikely(sta_rates)) { 266 wl->rate_set = wl1271_tx_enabled_rates_get(wl, sta_rates); 267 wl1271_acx_rate_policies(wl); 268 } 269 270 while ((skb = skb_dequeue(&wl->tx_queue))) { 271 if (!woken_up) { 272 ret = wl1271_ps_elp_wakeup(wl, false); 273 if (ret < 0) 274 goto out_ack; 275 woken_up = true; 276 } 277 278 ret = wl1271_tx_frame(wl, skb); 279 if (ret == -EBUSY) { 280 /* firmware buffer is full, lets stop transmitting. */ 281 skb_queue_head(&wl->tx_queue, skb); 282 goto out_ack; 283 } else if (ret < 0) { 284 dev_kfree_skb(skb); 285 goto out_ack; 286 } 287 } 288 289out_ack: 290 /* interrupt the firmware with the new packets */ 291 if (prev_tx_packets_count != wl->tx_packets_count) 292 wl1271_write32(wl, WL1271_HOST_WR_ACCESS, wl->tx_packets_count); 293 294out: 295 if (woken_up) 296 wl1271_ps_elp_sleep(wl); 297 298 mutex_unlock(&wl->mutex); 299} 300 301static void wl1271_tx_complete_packet(struct wl1271 *wl, 302 struct wl1271_tx_hw_res_descr *result) 303{ 304 struct ieee80211_tx_info *info; 305 struct sk_buff *skb; 306 int id = result->id; 307 int rate = -1; 308 u8 retries = 0; 309 310 /* check for id legality */ 311 if (unlikely(id >= ACX_TX_DESCRIPTORS || wl->tx_frames[id] == NULL)) { 312 wl1271_warning("TX result illegal id: %d", id); 313 return; 314 } 315 316 skb = wl->tx_frames[id]; 317 info = IEEE80211_SKB_CB(skb); 318 319 /* update the TX status info */ 320 if (result->status == TX_SUCCESS) { 321 if (!(info->flags & IEEE80211_TX_CTL_NO_ACK)) 322 info->flags |= IEEE80211_TX_STAT_ACK; 323 rate = wl1271_rate_to_idx(wl, result->rate_class_index); 324 retries = result->ack_failures; 325 } else if (result->status == TX_RETRY_EXCEEDED) { 326 wl->stats.excessive_retries++; 327 retries = result->ack_failures; 328 } 329 330 info->status.rates[0].idx = rate; 331 info->status.rates[0].count = retries; 332 info->status.rates[0].flags = 0; 333 info->status.ack_signal = -1; 334 335 wl->stats.retry_count += result->ack_failures; 336 337 /* update security sequence number */ 338 wl->tx_security_seq += (result->lsb_security_sequence_number - 339 wl->tx_security_last_seq); 340 wl->tx_security_last_seq = result->lsb_security_sequence_number; 341 342 /* remove private header from packet */ 343 skb_pull(skb, sizeof(struct wl1271_tx_hw_descr)); 344 345 /* remove TKIP header space if present */ 346 if (info->control.hw_key && 347 info->control.hw_key->alg == ALG_TKIP) { 348 int hdrlen = ieee80211_get_hdrlen_from_skb(skb); 349 memmove(skb->data + WL1271_TKIP_IV_SPACE, skb->data, hdrlen); 350 skb_pull(skb, WL1271_TKIP_IV_SPACE); 351 } 352 353 wl1271_debug(DEBUG_TX, "tx status id %u skb 0x%p failures %u rate 0x%x" 354 " status 0x%x", 355 result->id, skb, result->ack_failures, 356 result->rate_class_index, result->status); 357 358 /* return the packet to the stack */ 359 ieee80211_tx_status(wl->hw, skb); 360 wl->tx_frames[result->id] = NULL; 361} 362 363/* Called upon reception of a TX complete interrupt */ 364void wl1271_tx_complete(struct wl1271 *wl) 365{ 366 struct wl1271_acx_mem_map *memmap = 367 (struct wl1271_acx_mem_map *)wl->target_mem_map; 368 u32 count, fw_counter; 369 u32 i; 370 371 /* read the tx results from the chipset */ 372 wl1271_read(wl, le32_to_cpu(memmap->tx_result), 373 wl->tx_res_if, sizeof(*wl->tx_res_if), false); 374 fw_counter = le32_to_cpu(wl->tx_res_if->tx_result_fw_counter); 375 376 /* write host counter to chipset (to ack) */ 377 wl1271_write32(wl, le32_to_cpu(memmap->tx_result) + 378 offsetof(struct wl1271_tx_hw_res_if, 379 tx_result_host_counter), fw_counter); 380 381 count = fw_counter - wl->tx_results_count; 382 wl1271_debug(DEBUG_TX, "tx_complete received, packets: %d", count); 383 384 /* verify that the result buffer is not getting overrun */ 385 if (unlikely(count > TX_HW_RESULT_QUEUE_LEN)) 386 wl1271_warning("TX result overflow from chipset: %d", count); 387 388 /* process the results */ 389 for (i = 0; i < count; i++) { 390 struct wl1271_tx_hw_res_descr *result; 391 u8 offset = wl->tx_results_count & TX_HW_RESULT_QUEUE_LEN_MASK; 392 393 /* process the packet */ 394 result = &(wl->tx_res_if->tx_results_queue[offset]); 395 wl1271_tx_complete_packet(wl, result); 396 397 wl->tx_results_count++; 398 } 399 400 if (test_bit(WL1271_FLAG_TX_QUEUE_STOPPED, &wl->flags) && 401 skb_queue_len(&wl->tx_queue) <= WL1271_TX_QUEUE_LOW_WATERMARK) { 402 unsigned long flags; 403 404 /* firmware buffer has space, restart queues */ 405 wl1271_debug(DEBUG_TX, "tx_complete: waking queues"); 406 spin_lock_irqsave(&wl->wl_lock, flags); 407 ieee80211_wake_queues(wl->hw); 408 clear_bit(WL1271_FLAG_TX_QUEUE_STOPPED, &wl->flags); 409 spin_unlock_irqrestore(&wl->wl_lock, flags); 410 ieee80211_queue_work(wl->hw, &wl->tx_work); 411 } 412} 413 414/* caller must hold wl->mutex */ 415void wl1271_tx_flush(struct wl1271 *wl) 416{ 417 int i; 418 struct sk_buff *skb; 419 struct ieee80211_tx_info *info; 420 421 /* TX failure */ 422/* control->flags = 0; FIXME */ 423 424 while ((skb = skb_dequeue(&wl->tx_queue))) { 425 info = IEEE80211_SKB_CB(skb); 426 427 wl1271_debug(DEBUG_TX, "flushing skb 0x%p", skb); 428 429 if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) 430 continue; 431 432 ieee80211_tx_status(wl->hw, skb); 433 } 434 435 for (i = 0; i < ACX_TX_DESCRIPTORS; i++) 436 if (wl->tx_frames[i] != NULL) { 437 skb = wl->tx_frames[i]; 438 info = IEEE80211_SKB_CB(skb); 439 440 if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) 441 continue; 442 443 ieee80211_tx_status(wl->hw, skb); 444 wl->tx_frames[i] = NULL; 445 } 446} 447