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   1/******************************************************************************
   2 *
   3 * GPL LICENSE SUMMARY
   4 *
   5 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of version 2 of the GNU General Public License as
   9 * 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 Street, Fifth Floor, Boston, MA 02110,
  19 * USA
  20 *
  21 * The full GNU General Public License is included in this distribution
  22 * in the file called LICENSE.GPL.
  23 *
  24 * Contact Information:
  25 *  Intel Linux Wireless <ilw@linux.intel.com>
  26 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  27 *
  28 *****************************************************************************/
  29#include <linux/etherdevice.h>
  30#include <linux/kernel.h>
  31#include <linux/module.h>
  32#include <linux/init.h>
  33#include <linux/sched.h>
  34
  35#include "iwl-dev.h"
  36#include "iwl-core.h"
  37#include "iwl-io.h"
  38#include "iwl-helpers.h"
  39#include "iwl-4965-hw.h"
  40#include "iwl-4965.h"
  41#include "iwl-sta.h"
  42
  43void iwl4965_check_abort_status(struct iwl_priv *priv,
  44			    u8 frame_count, u32 status)
  45{
  46	if (frame_count == 1 && status == TX_STATUS_FAIL_RFKILL_FLUSH) {
  47		IWL_ERR(priv, "Tx flush command to flush out all frames\n");
  48		if (!test_bit(STATUS_EXIT_PENDING, &priv->status))
  49			queue_work(priv->workqueue, &priv->tx_flush);
  50	}
  51}
  52
  53/*
  54 * EEPROM
  55 */
  56struct iwl_mod_params iwl4965_mod_params = {
  57	.amsdu_size_8K = 1,
  58	.restart_fw = 1,
  59	/* the rest are 0 by default */
  60};
  61
  62void iwl4965_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
  63{
  64	unsigned long flags;
  65	int i;
  66	spin_lock_irqsave(&rxq->lock, flags);
  67	INIT_LIST_HEAD(&rxq->rx_free);
  68	INIT_LIST_HEAD(&rxq->rx_used);
  69	/* Fill the rx_used queue with _all_ of the Rx buffers */
  70	for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++) {
  71		/* In the reset function, these buffers may have been allocated
  72		 * to an SKB, so we need to unmap and free potential storage */
  73		if (rxq->pool[i].page != NULL) {
  74			pci_unmap_page(priv->pci_dev, rxq->pool[i].page_dma,
  75				PAGE_SIZE << priv->hw_params.rx_page_order,
  76				PCI_DMA_FROMDEVICE);
  77			__iwl_legacy_free_pages(priv, rxq->pool[i].page);
  78			rxq->pool[i].page = NULL;
  79		}
  80		list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
  81	}
  82
  83	for (i = 0; i < RX_QUEUE_SIZE; i++)
  84		rxq->queue[i] = NULL;
  85
  86	/* Set us so that we have processed and used all buffers, but have
  87	 * not restocked the Rx queue with fresh buffers */
  88	rxq->read = rxq->write = 0;
  89	rxq->write_actual = 0;
  90	rxq->free_count = 0;
  91	spin_unlock_irqrestore(&rxq->lock, flags);
  92}
  93
  94int iwl4965_rx_init(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
  95{
  96	u32 rb_size;
  97	const u32 rfdnlog = RX_QUEUE_SIZE_LOG; /* 256 RBDs */
  98	u32 rb_timeout = 0;
  99
 100	if (priv->cfg->mod_params->amsdu_size_8K)
 101		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K;
 102	else
 103		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;
 104
 105	/* Stop Rx DMA */
 106	iwl_legacy_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
 107
 108	/* Reset driver's Rx queue write index */
 109	iwl_legacy_write_direct32(priv, FH_RSCSR_CHNL0_RBDCB_WPTR_REG, 0);
 110
 111	/* Tell device where to find RBD circular buffer in DRAM */
 112	iwl_legacy_write_direct32(priv, FH_RSCSR_CHNL0_RBDCB_BASE_REG,
 113			   (u32)(rxq->bd_dma >> 8));
 114
 115	/* Tell device where in DRAM to update its Rx status */
 116	iwl_legacy_write_direct32(priv, FH_RSCSR_CHNL0_STTS_WPTR_REG,
 117			   rxq->rb_stts_dma >> 4);
 118
 119	/* Enable Rx DMA
 120	 * Direct rx interrupts to hosts
 121	 * Rx buffer size 4 or 8k
 122	 * RB timeout 0x10
 123	 * 256 RBDs
 124	 */
 125	iwl_legacy_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG,
 126			   FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL |
 127			   FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL |
 128			   FH_RCSR_CHNL0_RX_CONFIG_SINGLE_FRAME_MSK |
 129			   rb_size|
 130			   (rb_timeout << FH_RCSR_RX_CONFIG_REG_IRQ_RBTH_POS)|
 131			   (rfdnlog << FH_RCSR_RX_CONFIG_RBDCB_SIZE_POS));
 132
 133	/* Set interrupt coalescing timer to default (2048 usecs) */
 134	iwl_write8(priv, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
 135
 136	return 0;
 137}
 138
 139static void iwl4965_set_pwr_vmain(struct iwl_priv *priv)
 140{
 141/*
 142 * (for documentation purposes)
 143 * to set power to V_AUX, do:
 144
 145		if (pci_pme_capable(priv->pci_dev, PCI_D3cold))
 146			iwl_legacy_set_bits_mask_prph(priv, APMG_PS_CTRL_REG,
 147					       APMG_PS_CTRL_VAL_PWR_SRC_VAUX,
 148					       ~APMG_PS_CTRL_MSK_PWR_SRC);
 149 */
 150
 151	iwl_legacy_set_bits_mask_prph(priv, APMG_PS_CTRL_REG,
 152			       APMG_PS_CTRL_VAL_PWR_SRC_VMAIN,
 153			       ~APMG_PS_CTRL_MSK_PWR_SRC);
 154}
 155
 156int iwl4965_hw_nic_init(struct iwl_priv *priv)
 157{
 158	unsigned long flags;
 159	struct iwl_rx_queue *rxq = &priv->rxq;
 160	int ret;
 161
 162	/* nic_init */
 163	spin_lock_irqsave(&priv->lock, flags);
 164	priv->cfg->ops->lib->apm_ops.init(priv);
 165
 166	/* Set interrupt coalescing calibration timer to default (512 usecs) */
 167	iwl_write8(priv, CSR_INT_COALESCING, IWL_HOST_INT_CALIB_TIMEOUT_DEF);
 168
 169	spin_unlock_irqrestore(&priv->lock, flags);
 170
 171	iwl4965_set_pwr_vmain(priv);
 172
 173	priv->cfg->ops->lib->apm_ops.config(priv);
 174
 175	/* Allocate the RX queue, or reset if it is already allocated */
 176	if (!rxq->bd) {
 177		ret = iwl_legacy_rx_queue_alloc(priv);
 178		if (ret) {
 179			IWL_ERR(priv, "Unable to initialize Rx queue\n");
 180			return -ENOMEM;
 181		}
 182	} else
 183		iwl4965_rx_queue_reset(priv, rxq);
 184
 185	iwl4965_rx_replenish(priv);
 186
 187	iwl4965_rx_init(priv, rxq);
 188
 189	spin_lock_irqsave(&priv->lock, flags);
 190
 191	rxq->need_update = 1;
 192	iwl_legacy_rx_queue_update_write_ptr(priv, rxq);
 193
 194	spin_unlock_irqrestore(&priv->lock, flags);
 195
 196	/* Allocate or reset and init all Tx and Command queues */
 197	if (!priv->txq) {
 198		ret = iwl4965_txq_ctx_alloc(priv);
 199		if (ret)
 200			return ret;
 201	} else
 202		iwl4965_txq_ctx_reset(priv);
 203
 204	set_bit(STATUS_INIT, &priv->status);
 205
 206	return 0;
 207}
 208
 209/**
 210 * iwl4965_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr
 211 */
 212static inline __le32 iwl4965_dma_addr2rbd_ptr(struct iwl_priv *priv,
 213					  dma_addr_t dma_addr)
 214{
 215	return cpu_to_le32((u32)(dma_addr >> 8));
 216}
 217
 218/**
 219 * iwl4965_rx_queue_restock - refill RX queue from pre-allocated pool
 220 *
 221 * If there are slots in the RX queue that need to be restocked,
 222 * and we have free pre-allocated buffers, fill the ranks as much
 223 * as we can, pulling from rx_free.
 224 *
 225 * This moves the 'write' index forward to catch up with 'processed', and
 226 * also updates the memory address in the firmware to reference the new
 227 * target buffer.
 228 */
 229void iwl4965_rx_queue_restock(struct iwl_priv *priv)
 230{
 231	struct iwl_rx_queue *rxq = &priv->rxq;
 232	struct list_head *element;
 233	struct iwl_rx_mem_buffer *rxb;
 234	unsigned long flags;
 235
 236	spin_lock_irqsave(&rxq->lock, flags);
 237	while ((iwl_legacy_rx_queue_space(rxq) > 0) && (rxq->free_count)) {
 238		/* The overwritten rxb must be a used one */
 239		rxb = rxq->queue[rxq->write];
 240		BUG_ON(rxb && rxb->page);
 241
 242		/* Get next free Rx buffer, remove from free list */
 243		element = rxq->rx_free.next;
 244		rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
 245		list_del(element);
 246
 247		/* Point to Rx buffer via next RBD in circular buffer */
 248		rxq->bd[rxq->write] = iwl4965_dma_addr2rbd_ptr(priv,
 249							      rxb->page_dma);
 250		rxq->queue[rxq->write] = rxb;
 251		rxq->write = (rxq->write + 1) & RX_QUEUE_MASK;
 252		rxq->free_count--;
 253	}
 254	spin_unlock_irqrestore(&rxq->lock, flags);
 255	/* If the pre-allocated buffer pool is dropping low, schedule to
 256	 * refill it */
 257	if (rxq->free_count <= RX_LOW_WATERMARK)
 258		queue_work(priv->workqueue, &priv->rx_replenish);
 259
 260
 261	/* If we've added more space for the firmware to place data, tell it.
 262	 * Increment device's write pointer in multiples of 8. */
 263	if (rxq->write_actual != (rxq->write & ~0x7)) {
 264		spin_lock_irqsave(&rxq->lock, flags);
 265		rxq->need_update = 1;
 266		spin_unlock_irqrestore(&rxq->lock, flags);
 267		iwl_legacy_rx_queue_update_write_ptr(priv, rxq);
 268	}
 269}
 270
 271/**
 272 * iwl4965_rx_replenish - Move all used packet from rx_used to rx_free
 273 *
 274 * When moving to rx_free an SKB is allocated for the slot.
 275 *
 276 * Also restock the Rx queue via iwl_rx_queue_restock.
 277 * This is called as a scheduled work item (except for during initialization)
 278 */
 279static void iwl4965_rx_allocate(struct iwl_priv *priv, gfp_t priority)
 280{
 281	struct iwl_rx_queue *rxq = &priv->rxq;
 282	struct list_head *element;
 283	struct iwl_rx_mem_buffer *rxb;
 284	struct page *page;
 285	unsigned long flags;
 286	gfp_t gfp_mask = priority;
 287
 288	while (1) {
 289		spin_lock_irqsave(&rxq->lock, flags);
 290		if (list_empty(&rxq->rx_used)) {
 291			spin_unlock_irqrestore(&rxq->lock, flags);
 292			return;
 293		}
 294		spin_unlock_irqrestore(&rxq->lock, flags);
 295
 296		if (rxq->free_count > RX_LOW_WATERMARK)
 297			gfp_mask |= __GFP_NOWARN;
 298
 299		if (priv->hw_params.rx_page_order > 0)
 300			gfp_mask |= __GFP_COMP;
 301
 302		/* Alloc a new receive buffer */
 303		page = alloc_pages(gfp_mask, priv->hw_params.rx_page_order);
 304		if (!page) {
 305			if (net_ratelimit())
 306				IWL_DEBUG_INFO(priv, "alloc_pages failed, "
 307					       "order: %d\n",
 308					       priv->hw_params.rx_page_order);
 309
 310			if ((rxq->free_count <= RX_LOW_WATERMARK) &&
 311			    net_ratelimit())
 312				IWL_CRIT(priv,
 313					"Failed to alloc_pages with %s. "
 314					"Only %u free buffers remaining.\n",
 315					 priority == GFP_ATOMIC ?
 316						 "GFP_ATOMIC" : "GFP_KERNEL",
 317					 rxq->free_count);
 318			/* We don't reschedule replenish work here -- we will
 319			 * call the restock method and if it still needs
 320			 * more buffers it will schedule replenish */
 321			return;
 322		}
 323
 324		spin_lock_irqsave(&rxq->lock, flags);
 325
 326		if (list_empty(&rxq->rx_used)) {
 327			spin_unlock_irqrestore(&rxq->lock, flags);
 328			__free_pages(page, priv->hw_params.rx_page_order);
 329			return;
 330		}
 331		element = rxq->rx_used.next;
 332		rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
 333		list_del(element);
 334
 335		spin_unlock_irqrestore(&rxq->lock, flags);
 336
 337		BUG_ON(rxb->page);
 338		rxb->page = page;
 339		/* Get physical address of the RB */
 340		rxb->page_dma = pci_map_page(priv->pci_dev, page, 0,
 341				PAGE_SIZE << priv->hw_params.rx_page_order,
 342				PCI_DMA_FROMDEVICE);
 343		/* dma address must be no more than 36 bits */
 344		BUG_ON(rxb->page_dma & ~DMA_BIT_MASK(36));
 345		/* and also 256 byte aligned! */
 346		BUG_ON(rxb->page_dma & DMA_BIT_MASK(8));
 347
 348		spin_lock_irqsave(&rxq->lock, flags);
 349
 350		list_add_tail(&rxb->list, &rxq->rx_free);
 351		rxq->free_count++;
 352		priv->alloc_rxb_page++;
 353
 354		spin_unlock_irqrestore(&rxq->lock, flags);
 355	}
 356}
 357
 358void iwl4965_rx_replenish(struct iwl_priv *priv)
 359{
 360	unsigned long flags;
 361
 362	iwl4965_rx_allocate(priv, GFP_KERNEL);
 363
 364	spin_lock_irqsave(&priv->lock, flags);
 365	iwl4965_rx_queue_restock(priv);
 366	spin_unlock_irqrestore(&priv->lock, flags);
 367}
 368
 369void iwl4965_rx_replenish_now(struct iwl_priv *priv)
 370{
 371	iwl4965_rx_allocate(priv, GFP_ATOMIC);
 372
 373	iwl4965_rx_queue_restock(priv);
 374}
 375
 376/* Assumes that the skb field of the buffers in 'pool' is kept accurate.
 377 * If an SKB has been detached, the POOL needs to have its SKB set to NULL
 378 * This free routine walks the list of POOL entries and if SKB is set to
 379 * non NULL it is unmapped and freed
 380 */
 381void iwl4965_rx_queue_free(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
 382{
 383	int i;
 384	for (i = 0; i < RX_QUEUE_SIZE + RX_FREE_BUFFERS; i++) {
 385		if (rxq->pool[i].page != NULL) {
 386			pci_unmap_page(priv->pci_dev, rxq->pool[i].page_dma,
 387				PAGE_SIZE << priv->hw_params.rx_page_order,
 388				PCI_DMA_FROMDEVICE);
 389			__iwl_legacy_free_pages(priv, rxq->pool[i].page);
 390			rxq->pool[i].page = NULL;
 391		}
 392	}
 393
 394	dma_free_coherent(&priv->pci_dev->dev, 4 * RX_QUEUE_SIZE, rxq->bd,
 395			  rxq->bd_dma);
 396	dma_free_coherent(&priv->pci_dev->dev, sizeof(struct iwl_rb_status),
 397			  rxq->rb_stts, rxq->rb_stts_dma);
 398	rxq->bd = NULL;
 399	rxq->rb_stts  = NULL;
 400}
 401
 402int iwl4965_rxq_stop(struct iwl_priv *priv)
 403{
 404
 405	/* stop Rx DMA */
 406	iwl_legacy_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
 407	iwl_poll_direct_bit(priv, FH_MEM_RSSR_RX_STATUS_REG,
 408			    FH_RSSR_CHNL0_RX_STATUS_CHNL_IDLE, 1000);
 409
 410	return 0;
 411}
 412
 413int iwl4965_hwrate_to_mac80211_idx(u32 rate_n_flags, enum ieee80211_band band)
 414{
 415	int idx = 0;
 416	int band_offset = 0;
 417
 418	/* HT rate format: mac80211 wants an MCS number, which is just LSB */
 419	if (rate_n_flags & RATE_MCS_HT_MSK) {
 420		idx = (rate_n_flags & 0xff);
 421		return idx;
 422	/* Legacy rate format, search for match in table */
 423	} else {
 424		if (band == IEEE80211_BAND_5GHZ)
 425			band_offset = IWL_FIRST_OFDM_RATE;
 426		for (idx = band_offset; idx < IWL_RATE_COUNT_LEGACY; idx++)
 427			if (iwlegacy_rates[idx].plcp == (rate_n_flags & 0xFF))
 428				return idx - band_offset;
 429	}
 430
 431	return -1;
 432}
 433
 434static int iwl4965_calc_rssi(struct iwl_priv *priv,
 435			     struct iwl_rx_phy_res *rx_resp)
 436{
 437	/* data from PHY/DSP regarding signal strength, etc.,
 438	 *   contents are always there, not configurable by host.  */
 439	struct iwl4965_rx_non_cfg_phy *ncphy =
 440	    (struct iwl4965_rx_non_cfg_phy *)rx_resp->non_cfg_phy_buf;
 441	u32 agc = (le16_to_cpu(ncphy->agc_info) & IWL49_AGC_DB_MASK)
 442			>> IWL49_AGC_DB_POS;
 443
 444	u32 valid_antennae =
 445	    (le16_to_cpu(rx_resp->phy_flags) & IWL49_RX_PHY_FLAGS_ANTENNAE_MASK)
 446			>> IWL49_RX_PHY_FLAGS_ANTENNAE_OFFSET;
 447	u8 max_rssi = 0;
 448	u32 i;
 449
 450	/* Find max rssi among 3 possible receivers.
 451	 * These values are measured by the digital signal processor (DSP).
 452	 * They should stay fairly constant even as the signal strength varies,
 453	 *   if the radio's automatic gain control (AGC) is working right.
 454	 * AGC value (see below) will provide the "interesting" info. */
 455	for (i = 0; i < 3; i++)
 456		if (valid_antennae & (1 << i))
 457			max_rssi = max(ncphy->rssi_info[i << 1], max_rssi);
 458
 459	IWL_DEBUG_STATS(priv, "Rssi In A %d B %d C %d Max %d AGC dB %d\n",
 460		ncphy->rssi_info[0], ncphy->rssi_info[2], ncphy->rssi_info[4],
 461		max_rssi, agc);
 462
 463	/* dBm = max_rssi dB - agc dB - constant.
 464	 * Higher AGC (higher radio gain) means lower signal. */
 465	return max_rssi - agc - IWL4965_RSSI_OFFSET;
 466}
 467
 468
 469static u32 iwl4965_translate_rx_status(struct iwl_priv *priv, u32 decrypt_in)
 470{
 471	u32 decrypt_out = 0;
 472
 473	if ((decrypt_in & RX_RES_STATUS_STATION_FOUND) ==
 474					RX_RES_STATUS_STATION_FOUND)
 475		decrypt_out |= (RX_RES_STATUS_STATION_FOUND |
 476				RX_RES_STATUS_NO_STATION_INFO_MISMATCH);
 477
 478	decrypt_out |= (decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK);
 479
 480	/* packet was not encrypted */
 481	if ((decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) ==
 482					RX_RES_STATUS_SEC_TYPE_NONE)
 483		return decrypt_out;
 484
 485	/* packet was encrypted with unknown alg */
 486	if ((decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) ==
 487					RX_RES_STATUS_SEC_TYPE_ERR)
 488		return decrypt_out;
 489
 490	/* decryption was not done in HW */
 491	if ((decrypt_in & RX_MPDU_RES_STATUS_DEC_DONE_MSK) !=
 492					RX_MPDU_RES_STATUS_DEC_DONE_MSK)
 493		return decrypt_out;
 494
 495	switch (decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) {
 496
 497	case RX_RES_STATUS_SEC_TYPE_CCMP:
 498		/* alg is CCM: check MIC only */
 499		if (!(decrypt_in & RX_MPDU_RES_STATUS_MIC_OK))
 500			/* Bad MIC */
 501			decrypt_out |= RX_RES_STATUS_BAD_ICV_MIC;
 502		else
 503			decrypt_out |= RX_RES_STATUS_DECRYPT_OK;
 504
 505		break;
 506
 507	case RX_RES_STATUS_SEC_TYPE_TKIP:
 508		if (!(decrypt_in & RX_MPDU_RES_STATUS_TTAK_OK)) {
 509			/* Bad TTAK */
 510			decrypt_out |= RX_RES_STATUS_BAD_KEY_TTAK;
 511			break;
 512		}
 513		/* fall through if TTAK OK */
 514	default:
 515		if (!(decrypt_in & RX_MPDU_RES_STATUS_ICV_OK))
 516			decrypt_out |= RX_RES_STATUS_BAD_ICV_MIC;
 517		else
 518			decrypt_out |= RX_RES_STATUS_DECRYPT_OK;
 519		break;
 520	}
 521
 522	IWL_DEBUG_RX(priv, "decrypt_in:0x%x  decrypt_out = 0x%x\n",
 523					decrypt_in, decrypt_out);
 524
 525	return decrypt_out;
 526}
 527
 528static void iwl4965_pass_packet_to_mac80211(struct iwl_priv *priv,
 529					struct ieee80211_hdr *hdr,
 530					u16 len,
 531					u32 ampdu_status,
 532					struct iwl_rx_mem_buffer *rxb,
 533					struct ieee80211_rx_status *stats)
 534{
 535	struct sk_buff *skb;
 536	__le16 fc = hdr->frame_control;
 537
 538	/* We only process data packets if the interface is open */
 539	if (unlikely(!priv->is_open)) {
 540		IWL_DEBUG_DROP_LIMIT(priv,
 541		    "Dropping packet while interface is not open.\n");
 542		return;
 543	}
 544
 545	/* In case of HW accelerated crypto and bad decryption, drop */
 546	if (!priv->cfg->mod_params->sw_crypto &&
 547	    iwl_legacy_set_decrypted_flag(priv, hdr, ampdu_status, stats))
 548		return;
 549
 550	skb = dev_alloc_skb(128);
 551	if (!skb) {
 552		IWL_ERR(priv, "dev_alloc_skb failed\n");
 553		return;
 554	}
 555
 556	skb_add_rx_frag(skb, 0, rxb->page, (void *)hdr - rxb_addr(rxb), len);
 557
 558	iwl_legacy_update_stats(priv, false, fc, len);
 559	memcpy(IEEE80211_SKB_RXCB(skb), stats, sizeof(*stats));
 560
 561	ieee80211_rx(priv->hw, skb);
 562	priv->alloc_rxb_page--;
 563	rxb->page = NULL;
 564}
 565
 566/* Called for REPLY_RX (legacy ABG frames), or
 567 * REPLY_RX_MPDU_CMD (HT high-throughput N frames). */
 568void iwl4965_rx_reply_rx(struct iwl_priv *priv,
 569				struct iwl_rx_mem_buffer *rxb)
 570{
 571	struct ieee80211_hdr *header;
 572	struct ieee80211_rx_status rx_status;
 573	struct iwl_rx_packet *pkt = rxb_addr(rxb);
 574	struct iwl_rx_phy_res *phy_res;
 575	__le32 rx_pkt_status;
 576	struct iwl_rx_mpdu_res_start *amsdu;
 577	u32 len;
 578	u32 ampdu_status;
 579	u32 rate_n_flags;
 580
 581	/**
 582	 * REPLY_RX and REPLY_RX_MPDU_CMD are handled differently.
 583	 *	REPLY_RX: physical layer info is in this buffer
 584	 *	REPLY_RX_MPDU_CMD: physical layer info was sent in separate
 585	 *		command and cached in priv->last_phy_res
 586	 *
 587	 * Here we set up local variables depending on which command is
 588	 * received.
 589	 */
 590	if (pkt->hdr.cmd == REPLY_RX) {
 591		phy_res = (struct iwl_rx_phy_res *)pkt->u.raw;
 592		header = (struct ieee80211_hdr *)(pkt->u.raw + sizeof(*phy_res)
 593				+ phy_res->cfg_phy_cnt);
 594
 595		len = le16_to_cpu(phy_res->byte_count);
 596		rx_pkt_status = *(__le32 *)(pkt->u.raw + sizeof(*phy_res) +
 597				phy_res->cfg_phy_cnt + len);
 598		ampdu_status = le32_to_cpu(rx_pkt_status);
 599	} else {
 600		if (!priv->_4965.last_phy_res_valid) {
 601			IWL_ERR(priv, "MPDU frame without cached PHY data\n");
 602			return;
 603		}
 604		phy_res = &priv->_4965.last_phy_res;
 605		amsdu = (struct iwl_rx_mpdu_res_start *)pkt->u.raw;
 606		header = (struct ieee80211_hdr *)(pkt->u.raw + sizeof(*amsdu));
 607		len = le16_to_cpu(amsdu->byte_count);
 608		rx_pkt_status = *(__le32 *)(pkt->u.raw + sizeof(*amsdu) + len);
 609		ampdu_status = iwl4965_translate_rx_status(priv,
 610				le32_to_cpu(rx_pkt_status));
 611	}
 612
 613	if ((unlikely(phy_res->cfg_phy_cnt > 20))) {
 614		IWL_DEBUG_DROP(priv, "dsp size out of range [0,20]: %d/n",
 615				phy_res->cfg_phy_cnt);
 616		return;
 617	}
 618
 619	if (!(rx_pkt_status & RX_RES_STATUS_NO_CRC32_ERROR) ||
 620	    !(rx_pkt_status & RX_RES_STATUS_NO_RXE_OVERFLOW)) {
 621		IWL_DEBUG_RX(priv, "Bad CRC or FIFO: 0x%08X.\n",
 622				le32_to_cpu(rx_pkt_status));
 623		return;
 624	}
 625
 626	/* This will be used in several places later */
 627	rate_n_flags = le32_to_cpu(phy_res->rate_n_flags);
 628
 629	/* rx_status carries information about the packet to mac80211 */
 630	rx_status.mactime = le64_to_cpu(phy_res->timestamp);
 631	rx_status.band = (phy_res->phy_flags & RX_RES_PHY_FLAGS_BAND_24_MSK) ?
 632				IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ;
 633	rx_status.freq =
 634		ieee80211_channel_to_frequency(le16_to_cpu(phy_res->channel),
 635							rx_status.band);
 636	rx_status.rate_idx =
 637		iwl4965_hwrate_to_mac80211_idx(rate_n_flags, rx_status.band);
 638	rx_status.flag = 0;
 639
 640	/* TSF isn't reliable. In order to allow smooth user experience,
 641	 * this W/A doesn't propagate it to the mac80211 */
 642	/*rx_status.flag |= RX_FLAG_MACTIME_MPDU;*/
 643
 644	priv->ucode_beacon_time = le32_to_cpu(phy_res->beacon_time_stamp);
 645
 646	/* Find max signal strength (dBm) among 3 antenna/receiver chains */
 647	rx_status.signal = iwl4965_calc_rssi(priv, phy_res);
 648
 649	iwl_legacy_dbg_log_rx_data_frame(priv, len, header);
 650	IWL_DEBUG_STATS_LIMIT(priv, "Rssi %d, TSF %llu\n",
 651		rx_status.signal, (unsigned long long)rx_status.mactime);
 652
 653	/*
 654	 * "antenna number"
 655	 *
 656	 * It seems that the antenna field in the phy flags value
 657	 * is actually a bit field. This is undefined by radiotap,
 658	 * it wants an actual antenna number but I always get "7"
 659	 * for most legacy frames I receive indicating that the
 660	 * same frame was received on all three RX chains.
 661	 *
 662	 * I think this field should be removed in favor of a
 663	 * new 802.11n radiotap field "RX chains" that is defined
 664	 * as a bitmask.
 665	 */
 666	rx_status.antenna =
 667		(le16_to_cpu(phy_res->phy_flags) & RX_RES_PHY_FLAGS_ANTENNA_MSK)
 668		>> RX_RES_PHY_FLAGS_ANTENNA_POS;
 669
 670	/* set the preamble flag if appropriate */
 671	if (phy_res->phy_flags & RX_RES_PHY_FLAGS_SHORT_PREAMBLE_MSK)
 672		rx_status.flag |= RX_FLAG_SHORTPRE;
 673
 674	/* Set up the HT phy flags */
 675	if (rate_n_flags & RATE_MCS_HT_MSK)
 676		rx_status.flag |= RX_FLAG_HT;
 677	if (rate_n_flags & RATE_MCS_HT40_MSK)
 678		rx_status.flag |= RX_FLAG_40MHZ;
 679	if (rate_n_flags & RATE_MCS_SGI_MSK)
 680		rx_status.flag |= RX_FLAG_SHORT_GI;
 681
 682	iwl4965_pass_packet_to_mac80211(priv, header, len, ampdu_status,
 683				    rxb, &rx_status);
 684}
 685
 686/* Cache phy data (Rx signal strength, etc) for HT frame (REPLY_RX_PHY_CMD).
 687 * This will be used later in iwl_rx_reply_rx() for REPLY_RX_MPDU_CMD. */
 688void iwl4965_rx_reply_rx_phy(struct iwl_priv *priv,
 689			    struct iwl_rx_mem_buffer *rxb)
 690{
 691	struct iwl_rx_packet *pkt = rxb_addr(rxb);
 692	priv->_4965.last_phy_res_valid = true;
 693	memcpy(&priv->_4965.last_phy_res, pkt->u.raw,
 694	       sizeof(struct iwl_rx_phy_res));
 695}
 696
 697static int iwl4965_get_channels_for_scan(struct iwl_priv *priv,
 698				     struct ieee80211_vif *vif,
 699				     enum ieee80211_band band,
 700				     u8 is_active, u8 n_probes,
 701				     struct iwl_scan_channel *scan_ch)
 702{
 703	struct ieee80211_channel *chan;
 704	const struct ieee80211_supported_band *sband;
 705	const struct iwl_channel_info *ch_info;
 706	u16 passive_dwell = 0;
 707	u16 active_dwell = 0;
 708	int added, i;
 709	u16 channel;
 710
 711	sband = iwl_get_hw_mode(priv, band);
 712	if (!sband)
 713		return 0;
 714
 715	active_dwell = iwl_legacy_get_active_dwell_time(priv, band, n_probes);
 716	passive_dwell = iwl_legacy_get_passive_dwell_time(priv, band, vif);
 717
 718	if (passive_dwell <= active_dwell)
 719		passive_dwell = active_dwell + 1;
 720
 721	for (i = 0, added = 0; i < priv->scan_request->n_channels; i++) {
 722		chan = priv->scan_request->channels[i];
 723
 724		if (chan->band != band)
 725			continue;
 726
 727		channel = chan->hw_value;
 728		scan_ch->channel = cpu_to_le16(channel);
 729
 730		ch_info = iwl_legacy_get_channel_info(priv, band, channel);
 731		if (!iwl_legacy_is_channel_valid(ch_info)) {
 732			IWL_DEBUG_SCAN(priv,
 733				 "Channel %d is INVALID for this band.\n",
 734					channel);
 735			continue;
 736		}
 737
 738		if (!is_active || iwl_legacy_is_channel_passive(ch_info) ||
 739		    (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN))
 740			scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
 741		else
 742			scan_ch->type = SCAN_CHANNEL_TYPE_ACTIVE;
 743
 744		if (n_probes)
 745			scan_ch->type |= IWL_SCAN_PROBE_MASK(n_probes);
 746
 747		scan_ch->active_dwell = cpu_to_le16(active_dwell);
 748		scan_ch->passive_dwell = cpu_to_le16(passive_dwell);
 749
 750		/* Set txpower levels to defaults */
 751		scan_ch->dsp_atten = 110;
 752
 753		/* NOTE: if we were doing 6Mb OFDM for scans we'd use
 754		 * power level:
 755		 * scan_ch->tx_gain = ((1 << 5) | (2 << 3)) | 3;
 756		 */
 757		if (band == IEEE80211_BAND_5GHZ)
 758			scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
 759		else
 760			scan_ch->tx_gain = ((1 << 5) | (5 << 3));
 761
 762		IWL_DEBUG_SCAN(priv, "Scanning ch=%d prob=0x%X [%s %d]\n",
 763			       channel, le32_to_cpu(scan_ch->type),
 764			       (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
 765				"ACTIVE" : "PASSIVE",
 766			       (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
 767			       active_dwell : passive_dwell);
 768
 769		scan_ch++;
 770		added++;
 771	}
 772
 773	IWL_DEBUG_SCAN(priv, "total channels to scan %d\n", added);
 774	return added;
 775}
 776
 777int iwl4965_request_scan(struct iwl_priv *priv, struct ieee80211_vif *vif)
 778{
 779	struct iwl_host_cmd cmd = {
 780		.id = REPLY_SCAN_CMD,
 781		.len = sizeof(struct iwl_scan_cmd),
 782		.flags = CMD_SIZE_HUGE,
 783	};
 784	struct iwl_scan_cmd *scan;
 785	struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
 786	u32 rate_flags = 0;
 787	u16 cmd_len;
 788	u16 rx_chain = 0;
 789	enum ieee80211_band band;
 790	u8 n_probes = 0;
 791	u8 rx_ant = priv->hw_params.valid_rx_ant;
 792	u8 rate;
 793	bool is_active = false;
 794	int  chan_mod;
 795	u8 active_chains;
 796	u8 scan_tx_antennas = priv->hw_params.valid_tx_ant;
 797	int ret;
 798
 799	lockdep_assert_held(&priv->mutex);
 800
 801	if (vif)
 802		ctx = iwl_legacy_rxon_ctx_from_vif(vif);
 803
 804	if (!priv->scan_cmd) {
 805		priv->scan_cmd = kmalloc(sizeof(struct iwl_scan_cmd) +
 806					 IWL_MAX_SCAN_SIZE, GFP_KERNEL);
 807		if (!priv->scan_cmd) {
 808			IWL_DEBUG_SCAN(priv,
 809				       "fail to allocate memory for scan\n");
 810			return -ENOMEM;
 811		}
 812	}
 813	scan = priv->scan_cmd;
 814	memset(scan, 0, sizeof(struct iwl_scan_cmd) + IWL_MAX_SCAN_SIZE);
 815
 816	scan->quiet_plcp_th = IWL_PLCP_QUIET_THRESH;
 817	scan->quiet_time = IWL_ACTIVE_QUIET_TIME;
 818
 819	if (iwl_legacy_is_any_associated(priv)) {
 820		u16 interval;
 821		u32 extra;
 822		u32 suspend_time = 100;
 823		u32 scan_suspend_time = 100;
 824
 825		IWL_DEBUG_INFO(priv, "Scanning while associated...\n");
 826		interval = vif->bss_conf.beacon_int;
 827
 828		scan->suspend_time = 0;
 829		scan->max_out_time = cpu_to_le32(200 * 1024);
 830		if (!interval)
 831			interval = suspend_time;
 832
 833		extra = (suspend_time / interval) << 22;
 834		scan_suspend_time = (extra |
 835		    ((suspend_time % interval) * 1024));
 836		scan->suspend_time = cpu_to_le32(scan_suspend_time);
 837		IWL_DEBUG_SCAN(priv, "suspend_time 0x%X beacon interval %d\n",
 838			       scan_suspend_time, interval);
 839	}
 840
 841	if (priv->scan_request->n_ssids) {
 842		int i, p = 0;
 843		IWL_DEBUG_SCAN(priv, "Kicking off active scan\n");
 844		for (i = 0; i < priv->scan_request->n_ssids; i++) {
 845			/* always does wildcard anyway */
 846			if (!priv->scan_request->ssids[i].ssid_len)
 847				continue;
 848			scan->direct_scan[p].id = WLAN_EID_SSID;
 849			scan->direct_scan[p].len =
 850				priv->scan_request->ssids[i].ssid_len;
 851			memcpy(scan->direct_scan[p].ssid,
 852			       priv->scan_request->ssids[i].ssid,
 853			       priv->scan_request->ssids[i].ssid_len);
 854			n_probes++;
 855			p++;
 856		}
 857		is_active = true;
 858	} else
 859		IWL_DEBUG_SCAN(priv, "Start passive scan.\n");
 860
 861	scan->tx_cmd.tx_flags = TX_CMD_FLG_SEQ_CTL_MSK;
 862	scan->tx_cmd.sta_id = ctx->bcast_sta_id;
 863	scan->tx_cmd.stop_time.life_time = TX_CMD_LIFE_TIME_INFINITE;
 864
 865	switch (priv->scan_band) {
 866	case IEEE80211_BAND_2GHZ:
 867		scan->flags = RXON_FLG_BAND_24G_MSK | RXON_FLG_AUTO_DETECT_MSK;
 868		chan_mod = le32_to_cpu(
 869			priv->contexts[IWL_RXON_CTX_BSS].active.flags &
 870						RXON_FLG_CHANNEL_MODE_MSK)
 871				       >> RXON_FLG_CHANNEL_MODE_POS;
 872		if (chan_mod == CHANNEL_MODE_PURE_40) {
 873			rate = IWL_RATE_6M_PLCP;
 874		} else {
 875			rate = IWL_RATE_1M_PLCP;
 876			rate_flags = RATE_MCS_CCK_MSK;
 877		}
 878		break;
 879	case IEEE80211_BAND_5GHZ:
 880		rate = IWL_RATE_6M_PLCP;
 881		break;
 882	default:
 883		IWL_WARN(priv, "Invalid scan band\n");
 884		return -EIO;
 885	}
 886
 887	/*
 888	 * If active scanning is requested but a certain channel is
 889	 * marked passive, we can do active scanning if we detect
 890	 * transmissions.
 891	 *
 892	 * There is an issue with some firmware versions that triggers
 893	 * a sysassert on a "good CRC threshold" of zero (== disabled),
 894	 * on a radar channel even though this means that we should NOT
 895	 * send probes.
 896	 *
 897	 * The "good CRC threshold" is the number of frames that we
 898	 * need to receive during our dwell time on a channel before
 899	 * sending out probes -- setting this to a huge value will
 900	 * mean we never reach it, but at the same time work around
 901	 * the aforementioned issue. Thus use IWL_GOOD_CRC_TH_NEVER
 902	 * here instead of IWL_GOOD_CRC_TH_DISABLED.
 903	 */
 904	scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT :
 905					IWL_GOOD_CRC_TH_NEVER;
 906
 907	band = priv->scan_band;
 908
 909	if (priv->cfg->scan_rx_antennas[band])
 910		rx_ant = priv->cfg->scan_rx_antennas[band];
 911
 912	priv->scan_tx_ant[band] = iwl4965_toggle_tx_ant(priv,
 913						priv->scan_tx_ant[band],
 914						    scan_tx_antennas);
 915	rate_flags |= iwl4965_ant_idx_to_flags(priv->scan_tx_ant[band]);
 916	scan->tx_cmd.rate_n_flags = iwl4965_hw_set_rate_n_flags(rate, rate_flags);
 917
 918	/* In power save mode use one chain, otherwise use all chains */
 919	if (test_bit(STATUS_POWER_PMI, &priv->status)) {
 920		/* rx_ant has been set to all valid chains previously */
 921		active_chains = rx_ant &
 922				((u8)(priv->chain_noise_data.active_chains));
 923		if (!active_chains)
 924			active_chains = rx_ant;
 925
 926		IWL_DEBUG_SCAN(priv, "chain_noise_data.active_chains: %u\n",
 927				priv->chain_noise_data.active_chains);
 928
 929		rx_ant = iwl4965_first_antenna(active_chains);
 930	}
 931
 932	/* MIMO is not used here, but value is required */
 933	rx_chain |= priv->hw_params.valid_rx_ant << RXON_RX_CHAIN_VALID_POS;
 934	rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS;
 935	rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_SEL_POS;
 936	rx_chain |= 0x1 << RXON_RX_CHAIN_DRIVER_FORCE_POS;
 937	scan->rx_chain = cpu_to_le16(rx_chain);
 938
 939	cmd_len = iwl_legacy_fill_probe_req(priv,
 940					(struct ieee80211_mgmt *)scan->data,
 941					vif->addr,
 942					priv->scan_request->ie,
 943					priv->scan_request->ie_len,
 944					IWL_MAX_SCAN_SIZE - sizeof(*scan));
 945	scan->tx_cmd.len = cpu_to_le16(cmd_len);
 946
 947	scan->filter_flags |= (RXON_FILTER_ACCEPT_GRP_MSK |
 948			       RXON_FILTER_BCON_AWARE_MSK);
 949
 950	scan->channel_count = iwl4965_get_channels_for_scan(priv, vif, band,
 951						is_active, n_probes,
 952						(void *)&scan->data[cmd_len]);
 953	if (scan->channel_count == 0) {
 954		IWL_DEBUG_SCAN(priv, "channel count %d\n", scan->channel_count);
 955		return -EIO;
 956	}
 957
 958	cmd.len += le16_to_cpu(scan->tx_cmd.len) +
 959	    scan->channel_count * sizeof(struct iwl_scan_channel);
 960	cmd.data = scan;
 961	scan->len = cpu_to_le16(cmd.len);
 962
 963	set_bit(STATUS_SCAN_HW, &priv->status);
 964
 965	ret = iwl_legacy_send_cmd_sync(priv, &cmd);
 966	if (ret)
 967		clear_bit(STATUS_SCAN_HW, &priv->status);
 968
 969	return ret;
 970}
 971
 972int iwl4965_manage_ibss_station(struct iwl_priv *priv,
 973			       struct ieee80211_vif *vif, bool add)
 974{
 975	struct iwl_vif_priv *vif_priv = (void *)vif->drv_priv;
 976
 977	if (add)
 978		return iwl4965_add_bssid_station(priv, vif_priv->ctx,
 979						vif->bss_conf.bssid,
 980						&vif_priv->ibss_bssid_sta_id);
 981	return iwl_legacy_remove_station(priv, vif_priv->ibss_bssid_sta_id,
 982				  vif->bss_conf.bssid);
 983}
 984
 985void iwl4965_free_tfds_in_queue(struct iwl_priv *priv,
 986			    int sta_id, int tid, int freed)
 987{
 988	lockdep_assert_held(&priv->sta_lock);
 989
 990	if (priv->stations[sta_id].tid[tid].tfds_in_queue >= freed)
 991		priv->stations[sta_id].tid[tid].tfds_in_queue -= freed;
 992	else {
 993		IWL_DEBUG_TX(priv, "free more than tfds_in_queue (%u:%d)\n",
 994			priv->stations[sta_id].tid[tid].tfds_in_queue,
 995			freed);
 996		priv->stations[sta_id].tid[tid].tfds_in_queue = 0;
 997	}
 998}
 999
1000#define IWL_TX_QUEUE_MSK	0xfffff
1001
1002static bool iwl4965_is_single_rx_stream(struct iwl_priv *priv)
1003{
1004	return priv->current_ht_config.smps == IEEE80211_SMPS_STATIC ||
1005	       priv->current_ht_config.single_chain_sufficient;
1006}
1007
1008#define IWL_NUM_RX_CHAINS_MULTIPLE	3
1009#define IWL_NUM_RX_CHAINS_SINGLE	2
1010#define IWL_NUM_IDLE_CHAINS_DUAL	2
1011#define IWL_NUM_IDLE_CHAINS_SINGLE	1
1012
1013/*
1014 * Determine how many receiver/antenna chains to use.
1015 *
1016 * More provides better reception via diversity.  Fewer saves power
1017 * at the expense of throughput, but only when not in powersave to
1018 * start with.
1019 *
1020 * MIMO (dual stream) requires at least 2, but works better with 3.
1021 * This does not determine *which* chains to use, just how many.
1022 */
1023static int iwl4965_get_active_rx_chain_count(struct iwl_priv *priv)
1024{
1025	/* # of Rx chains to use when expecting MIMO. */
1026	if (iwl4965_is_single_rx_stream(priv))
1027		return IWL_NUM_RX_CHAINS_SINGLE;
1028	else
1029		return IWL_NUM_RX_CHAINS_MULTIPLE;
1030}
1031
1032/*
1033 * When we are in power saving mode, unless device support spatial
1034 * multiplexing power save, use the active count for rx chain count.
1035 */
1036static int
1037iwl4965_get_idle_rx_chain_count(struct iwl_priv *priv, int active_cnt)
1038{
1039	/* # Rx chains when idling, depending on SMPS mode */
1040	switch (priv->current_ht_config.smps) {
1041	case IEEE80211_SMPS_STATIC:
1042	case IEEE80211_SMPS_DYNAMIC:
1043		return IWL_NUM_IDLE_CHAINS_SINGLE;
1044	case IEEE80211_SMPS_OFF:
1045		return active_cnt;
1046	default:
1047		WARN(1, "invalid SMPS mode %d",
1048		     priv->current_ht_config.smps);
1049		return active_cnt;
1050	}
1051}
1052
1053/* up to 4 chains */
1054static u8 iwl4965_count_chain_bitmap(u32 chain_bitmap)
1055{
1056	u8 res;
1057	res = (chain_bitmap & BIT(0)) >> 0;
1058	res += (chain_bitmap & BIT(1)) >> 1;
1059	res += (chain_bitmap & BIT(2)) >> 2;
1060	res += (chain_bitmap & BIT(3)) >> 3;
1061	return res;
1062}
1063
1064/**
1065 * iwl4965_set_rxon_chain - Set up Rx chain usage in "staging" RXON image
1066 *
1067 * Selects how many and which Rx receivers/antennas/chains to use.
1068 * This should not be used for scan command ... it puts data in wrong place.
1069 */
1070void iwl4965_set_rxon_chain(struct iwl_priv *priv, struct iwl_rxon_context *ctx)
1071{
1072	bool is_single = iwl4965_is_single_rx_stream(priv);
1073	bool is_cam = !test_bit(STATUS_POWER_PMI, &priv->status);
1074	u8 idle_rx_cnt, active_rx_cnt, valid_rx_cnt;
1075	u32 active_chains;
1076	u16 rx_chain;
1077
1078	/* Tell uCode which antennas are actually connected.
1079	 * Before first association, we assume all antennas are connected.
1080	 * Just after first association, iwl4965_chain_noise_calibration()
1081	 *    checks which antennas actually *are* connected. */
1082	if (priv->chain_noise_data.active_chains)
1083		active_chains = priv->chain_noise_data.active_chains;
1084	else
1085		active_chains = priv->hw_params.valid_rx_ant;
1086
1087	rx_chain = active_chains << RXON_RX_CHAIN_VALID_POS;
1088
1089	/* How many receivers should we use? */
1090	active_rx_cnt = iwl4965_get_active_rx_chain_count(priv);
1091	idle_rx_cnt = iwl4965_get_idle_rx_chain_count(priv, active_rx_cnt);
1092
1093
1094	/* correct rx chain count according hw settings
1095	 * and chain noise calibration
1096	 */
1097	valid_rx_cnt = iwl4965_count_chain_bitmap(active_chains);
1098	if (valid_rx_cnt < active_rx_cnt)
1099		active_rx_cnt = valid_rx_cnt;
1100
1101	if (valid_rx_cnt < idle_rx_cnt)
1102		idle_rx_cnt = valid_rx_cnt;
1103
1104	rx_chain |= active_rx_cnt << RXON_RX_CHAIN_MIMO_CNT_POS;
1105	rx_chain |= idle_rx_cnt  << RXON_RX_CHAIN_CNT_POS;
1106
1107	ctx->staging.rx_chain = cpu_to_le16(rx_chain);
1108
1109	if (!is_single && (active_rx_cnt >= IWL_NUM_RX_CHAINS_SINGLE) && is_cam)
1110		ctx->staging.rx_chain |= RXON_RX_CHAIN_MIMO_FORCE_MSK;
1111	else
1112		ctx->staging.rx_chain &= ~RXON_RX_CHAIN_MIMO_FORCE_MSK;
1113
1114	IWL_DEBUG_ASSOC(priv, "rx_chain=0x%X active=%d idle=%d\n",
1115			ctx->staging.rx_chain,
1116			active_rx_cnt, idle_rx_cnt);
1117
1118	WARN_ON(active_rx_cnt == 0 || idle_rx_cnt == 0 ||
1119		active_rx_cnt < idle_rx_cnt);
1120}
1121
1122u8 iwl4965_toggle_tx_ant(struct iwl_priv *priv, u8 ant, u8 valid)
1123{
1124	int i;
1125	u8 ind = ant;
1126
1127	for (i = 0; i < RATE_ANT_NUM - 1; i++) {
1128		ind = (ind + 1) < RATE_ANT_NUM ?  ind + 1 : 0;
1129		if (valid & BIT(ind))
1130			return ind;
1131	}
1132	return ant;
1133}
1134
1135static const char *iwl4965_get_fh_string(int cmd)
1136{
1137	switch (cmd) {
1138	IWL_CMD(FH_RSCSR_CHNL0_STTS_WPTR_REG);
1139	IWL_CMD(FH_RSCSR_CHNL0_RBDCB_BASE_REG);
1140	IWL_CMD(FH_RSCSR_CHNL0_WPTR);
1141	IWL_CMD(FH_MEM_RCSR_CHNL0_CONFIG_REG);
1142	IWL_CMD(FH_MEM_RSSR_SHARED_CTRL_REG);
1143	IWL_CMD(FH_MEM_RSSR_RX_STATUS_REG);
1144	IWL_CMD(FH_MEM_RSSR_RX_ENABLE_ERR_IRQ2DRV);
1145	IWL_CMD(FH_TSSR_TX_STATUS_REG);
1146	IWL_CMD(FH_TSSR_TX_ERROR_REG);
1147	default:
1148		return "UNKNOWN";
1149	}
1150}
1151
1152int iwl4965_dump_fh(struct iwl_priv *priv, char **buf, bool display)
1153{
1154	int i;
1155#ifdef CONFIG_IWLWIFI_LEGACY_DEBUG
1156	int pos = 0;
1157	size_t bufsz = 0;
1158#endif
1159	static const u32 fh_tbl[] = {
1160		FH_RSCSR_CHNL0_STTS_WPTR_REG,
1161		FH_RSCSR_CHNL0_RBDCB_BASE_REG,
1162		FH_RSCSR_CHNL0_WPTR,
1163		FH_MEM_RCSR_CHNL0_CONFIG_REG,
1164		FH_MEM_RSSR_SHARED_CTRL_REG,
1165		FH_MEM_RSSR_RX_STATUS_REG,
1166		FH_MEM_RSSR_RX_ENABLE_ERR_IRQ2DRV,
1167		FH_TSSR_TX_STATUS_REG,
1168		FH_TSSR_TX_ERROR_REG
1169	};
1170#ifdef CONFIG_IWLWIFI_LEGACY_DEBUG
1171	if (display) {
1172		bufsz = ARRAY_SIZE(fh_tbl) * 48 + 40;
1173		*buf = kmalloc(bufsz, GFP_KERNEL);
1174		if (!*buf)
1175			return -ENOMEM;
1176		pos += scnprintf(*buf + pos, bufsz - pos,
1177				"FH register values:\n");
1178		for (i = 0; i < ARRAY_SIZE(fh_tbl); i++) {
1179			pos += scnprintf(*buf + pos, bufsz - pos,
1180				"  %34s: 0X%08x\n",
1181				iwl4965_get_fh_string(fh_tbl[i]),
1182				iwl_legacy_read_direct32(priv, fh_tbl[i]));
1183		}
1184		return pos;
1185	}
1186#endif
1187	IWL_ERR(priv, "FH register values:\n");
1188	for (i = 0; i <  ARRAY_SIZE(fh_tbl); i++) {
1189		IWL_ERR(priv, "  %34s: 0X%08x\n",
1190			iwl4965_get_fh_string(fh_tbl[i]),
1191			iwl_legacy_read_direct32(priv, fh_tbl[i]));
1192	}
1193	return 0;
1194}