base.c

/*-
 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
 * Copyright (c) 2004-2005 Atheros Communications, Inc.
 * Copyright (c) 2006 Devicescape Software, Inc.
 * Copyright (c) 2007 Jiri Slaby <jirislaby@gmail.com>
 * Copyright (c) 2007 Luis R. Rodriguez <mcgrof@winlab.rutgers.edu>
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
 *    redistribution must be conditioned upon including a substantially
 *    similar Disclaimer requirement for further binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGES.
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/hardirq.h>
#include <linux/if.h>
#include <linux/io.h>
#include <linux/netdevice.h>
#include <linux/cache.h>
#include <linux/ethtool.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/etherdevice.h>
#include <linux/nl80211.h>

#include <net/ieee80211_radiotap.h>

#include <asm/unaligned.h>

#include "base.h"
#include "reg.h"
#include "debug.h"
#include "ani.h"
#include "ath5k.h"
#include "../regd.h"

#define CREATE_TRACE_POINTS
#include "trace.h"

bool ath5k_modparam_nohwcrypt;
module_param_named(nohwcrypt, ath5k_modparam_nohwcrypt, bool, S_IRUGO);
MODULE_PARM_DESC(nohwcrypt, "Disable hardware encryption.");

static bool modparam_all_channels;
module_param_named(all_channels, modparam_all_channels, bool, S_IRUGO);
MODULE_PARM_DESC(all_channels, "Expose all channels the device can use.");

static bool modparam_fastchanswitch;
module_param_named(fastchanswitch, modparam_fastchanswitch, bool, S_IRUGO);
MODULE_PARM_DESC(fastchanswitch, "Enable fast channel switching for AR2413/AR5413 radios.");

static bool ath5k_modparam_no_hw_rfkill_switch;
module_param_named(no_hw_rfkill_switch, ath5k_modparam_no_hw_rfkill_switch,
								bool, S_IRUGO);
MODULE_PARM_DESC(no_hw_rfkill_switch, "Ignore the GPIO RFKill switch state");


/* Module info */
MODULE_AUTHOR("Jiri Slaby");
MODULE_AUTHOR("Nick Kossifidis");
MODULE_DESCRIPTION("Support for 5xxx series of Atheros 802.11 wireless LAN cards.");
MODULE_SUPPORTED_DEVICE("Atheros 5xxx WLAN cards");
MODULE_LICENSE("Dual BSD/GPL");

static int ath5k_init(struct ieee80211_hw *hw);
static int ath5k_reset(struct ath5k_hw *ah, struct ieee80211_channel *chan,
								bool skip_pcu);

/* Known SREVs */
static const struct ath5k_srev_name srev_names[] = {
#ifdef CONFIG_ATHEROS_AR231X
	{ "5312",	AR5K_VERSION_MAC,	AR5K_SREV_AR5312_R2 },
	{ "5312",	AR5K_VERSION_MAC,	AR5K_SREV_AR5312_R7 },
	{ "2313",	AR5K_VERSION_MAC,	AR5K_SREV_AR2313_R8 },
	{ "2315",	AR5K_VERSION_MAC,	AR5K_SREV_AR2315_R6 },
	{ "2315",	AR5K_VERSION_MAC,	AR5K_SREV_AR2315_R7 },
	{ "2317",	AR5K_VERSION_MAC,	AR5K_SREV_AR2317_R1 },
	{ "2317",	AR5K_VERSION_MAC,	AR5K_SREV_AR2317_R2 },
#else
	{ "5210",	AR5K_VERSION_MAC,	AR5K_SREV_AR5210 },
	{ "5311",	AR5K_VERSION_MAC,	AR5K_SREV_AR5311 },
	{ "5311A",	AR5K_VERSION_MAC,	AR5K_SREV_AR5311A },
	{ "5311B",	AR5K_VERSION_MAC,	AR5K_SREV_AR5311B },
	{ "5211",	AR5K_VERSION_MAC,	AR5K_SREV_AR5211 },
	{ "5212",	AR5K_VERSION_MAC,	AR5K_SREV_AR5212 },
	{ "5213",	AR5K_VERSION_MAC,	AR5K_SREV_AR5213 },
	{ "5213A",	AR5K_VERSION_MAC,	AR5K_SREV_AR5213A },
	{ "2413",	AR5K_VERSION_MAC,	AR5K_SREV_AR2413 },
	{ "2414",	AR5K_VERSION_MAC,	AR5K_SREV_AR2414 },
	{ "5424",	AR5K_VERSION_MAC,	AR5K_SREV_AR5424 },
	{ "5413",	AR5K_VERSION_MAC,	AR5K_SREV_AR5413 },
	{ "5414",	AR5K_VERSION_MAC,	AR5K_SREV_AR5414 },
	{ "2415",	AR5K_VERSION_MAC,	AR5K_SREV_AR2415 },
	{ "5416",	AR5K_VERSION_MAC,	AR5K_SREV_AR5416 },
	{ "5418",	AR5K_VERSION_MAC,	AR5K_SREV_AR5418 },
	{ "2425",	AR5K_VERSION_MAC,	AR5K_SREV_AR2425 },
	{ "2417",	AR5K_VERSION_MAC,	AR5K_SREV_AR2417 },
#endif
	{ "xxxxx",	AR5K_VERSION_MAC,	AR5K_SREV_UNKNOWN },
	{ "5110",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_5110 },
	{ "5111",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_5111 },
	{ "5111A",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_5111A },
	{ "2111",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_2111 },
	{ "5112",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_5112 },
	{ "5112A",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_5112A },
	{ "5112B",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_5112B },
	{ "2112",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_2112 },
	{ "2112A",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_2112A },
	{ "2112B",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_2112B },
	{ "2413",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_2413 },
	{ "5413",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_5413 },
	{ "5424",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_5424 },
	{ "5133",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_5133 },
#ifdef CONFIG_ATHEROS_AR231X
	{ "2316",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_2316 },
	{ "2317",	AR5K_VERSION_RAD,	AR5K_SREV_RAD_2317 },
#endif
	{ "xxxxx",	AR5K_VERSION_RAD,	AR5K_SREV_UNKNOWN },
};

static const struct ieee80211_rate ath5k_rates[] = {
	{ .bitrate = 10,
	  .hw_value = ATH5K_RATE_CODE_1M, },
	{ .bitrate = 20,
	  .hw_value = ATH5K_RATE_CODE_2M,
	  .hw_value_short = ATH5K_RATE_CODE_2M | AR5K_SET_SHORT_PREAMBLE,
	  .flags = IEEE80211_RATE_SHORT_PREAMBLE },
	{ .bitrate = 55,
	  .hw_value = ATH5K_RATE_CODE_5_5M,
	  .hw_value_short = ATH5K_RATE_CODE_5_5M | AR5K_SET_SHORT_PREAMBLE,
	  .flags = IEEE80211_RATE_SHORT_PREAMBLE },
	{ .bitrate = 110,
	  .hw_value = ATH5K_RATE_CODE_11M,
	  .hw_value_short = ATH5K_RATE_CODE_11M | AR5K_SET_SHORT_PREAMBLE,
	  .flags = IEEE80211_RATE_SHORT_PREAMBLE },
	{ .bitrate = 60,
	  .hw_value = ATH5K_RATE_CODE_6M,
	  .flags = 0 },
	{ .bitrate = 90,
	  .hw_value = ATH5K_RATE_CODE_9M,
	  .flags = 0 },
	{ .bitrate = 120,
	  .hw_value = ATH5K_RATE_CODE_12M,
	  .flags = 0 },
	{ .bitrate = 180,
	  .hw_value = ATH5K_RATE_CODE_18M,
	  .flags = 0 },
	{ .bitrate = 240,
	  .hw_value = ATH5K_RATE_CODE_24M,
	  .flags = 0 },
	{ .bitrate = 360,
	  .hw_value = ATH5K_RATE_CODE_36M,
	  .flags = 0 },
	{ .bitrate = 480,
	  .hw_value = ATH5K_RATE_CODE_48M,
	  .flags = 0 },
	{ .bitrate = 540,
	  .hw_value = ATH5K_RATE_CODE_54M,
	  .flags = 0 },
};

static inline u64 ath5k_extend_tsf(struct ath5k_hw *ah, u32 rstamp)
{
	u64 tsf = ath5k_hw_get_tsf64(ah);

	if ((tsf & 0x7fff) < rstamp)
		tsf -= 0x8000;

	return (tsf & ~0x7fff) | rstamp;
}

const char *
ath5k_chip_name(enum ath5k_srev_type type, u_int16_t val)
{
	const char *name = "xxxxx";
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(srev_names); i++) {
		if (srev_names[i].sr_type != type)
			continue;

		if ((val & 0xf0) == srev_names[i].sr_val)
			name = srev_names[i].sr_name;

		if ((val & 0xff) == srev_names[i].sr_val) {
			name = srev_names[i].sr_name;
			break;
		}
	}

	return name;
}
static unsigned int ath5k_ioread32(void *hw_priv, u32 reg_offset)
{
	struct ath5k_hw *ah = (struct ath5k_hw *) hw_priv;
	return ath5k_hw_reg_read(ah, reg_offset);
}

static void ath5k_iowrite32(void *hw_priv, u32 val, u32 reg_offset)
{
	struct ath5k_hw *ah = (struct ath5k_hw *) hw_priv;
	ath5k_hw_reg_write(ah, val, reg_offset);
}

static const struct ath_ops ath5k_common_ops = {
	.read = ath5k_ioread32,
	.write = ath5k_iowrite32,
};

/***********************\
* Driver Initialization *
\***********************/

static int ath5k_reg_notifier(struct wiphy *wiphy, struct regulatory_request *request)
{
	struct ieee80211_hw *hw = wiphy_to_ieee80211_hw(wiphy);
	struct ath5k_hw *ah = hw->priv;
	struct ath_regulatory *regulatory = ath5k_hw_regulatory(ah);

	return ath_reg_notifier_apply(wiphy, request, regulatory);
}

/********************\
* Channel/mode setup *
\********************/

/*
 * Returns true for the channel numbers used without all_channels modparam.
 */
static bool ath5k_is_standard_channel(short chan, enum ieee80211_band band)
{
	if (band == IEEE80211_BAND_2GHZ && chan <= 14)
		return true;

	return	/* UNII 1,2 */
		(((chan & 3) == 0 && chan >= 36 && chan <= 64) ||
		/* midband */
		((chan & 3) == 0 && chan >= 100 && chan <= 140) ||
		/* UNII-3 */
		((chan & 3) == 1 && chan >= 149 && chan <= 165) ||
		/* 802.11j 5.030-5.080 GHz (20MHz) */
		(chan == 8 || chan == 12 || chan == 16) ||
		/* 802.11j 4.9GHz (20MHz) */
		(chan == 184 || chan == 188 || chan == 192 || chan == 196));
}

static unsigned int
ath5k_setup_channels(struct ath5k_hw *ah, struct ieee80211_channel *channels,
		unsigned int mode, unsigned int max)
{
	unsigned int count, size, freq, ch;
	enum ieee80211_band band;

	switch (mode) {
	case AR5K_MODE_11A:
		/* 1..220, but 2GHz frequencies are filtered by check_channel */
		size = 220;
		band = IEEE80211_BAND_5GHZ;
		break;
	case AR5K_MODE_11B:
	case AR5K_MODE_11G:
		size = 26;
		band = IEEE80211_BAND_2GHZ;
		break;
	default:
		ATH5K_WARN(ah, "bad mode, not copying channels\n");
		return 0;
	}

	count = 0;
	for (ch = 1; ch <= size && count < max; ch++) {
		freq = ieee80211_channel_to_frequency(ch, band);

		if (freq == 0) /* mapping failed - not a standard channel */
			continue;

		/* Write channel info, needed for ath5k_channel_ok() */
		channels[count].center_freq = freq;
		channels[count].band = band;
		channels[count].hw_value = mode;

		/* Check if channel is supported by the chipset */
		if (!ath5k_channel_ok(ah, &channels[count]))
			continue;

		if (!modparam_all_channels &&
		    !ath5k_is_standard_channel(ch, band))
			continue;

		count++;
	}

	return count;
}

static void
ath5k_setup_rate_idx(struct ath5k_hw *ah, struct ieee80211_supported_band *b)
{
	u8 i;

	for (i = 0; i < AR5K_MAX_RATES; i++)
		ah->rate_idx[b->band][i] = -1;

	for (i = 0; i < b->n_bitrates; i++) {
		ah->rate_idx[b->band][b->bitrates[i].hw_value] = i;
		if (b->bitrates[i].hw_value_short)
			ah->rate_idx[b->band][b->bitrates[i].hw_value_short] = i;
	}
}

static int
ath5k_setup_bands(struct ieee80211_hw *hw)
{
	struct ath5k_hw *ah = hw->priv;
	struct ieee80211_supported_band *sband;
	int max_c, count_c = 0;
	int i;

	BUILD_BUG_ON(ARRAY_SIZE(ah->sbands) < IEEE80211_NUM_BANDS);
	max_c = ARRAY_SIZE(ah->channels);

	/* 2GHz band */
	sband = &ah->sbands[IEEE80211_BAND_2GHZ];
	sband->band = IEEE80211_BAND_2GHZ;
	sband->bitrates = &ah->rates[IEEE80211_BAND_2GHZ][0];

	if (test_bit(AR5K_MODE_11G, ah->ah_capabilities.cap_mode)) {
		/* G mode */
		memcpy(sband->bitrates, &ath5k_rates[0],
		       sizeof(struct ieee80211_rate) * 12);
		sband->n_bitrates = 12;

		sband->channels = ah->channels;
		sband->n_channels = ath5k_setup_channels(ah, sband->channels,
					AR5K_MODE_11G, max_c);

		hw->wiphy->bands[IEEE80211_BAND_2GHZ] = sband;
		count_c = sband->n_channels;
		max_c -= count_c;
	} else if (test_bit(AR5K_MODE_11B, ah->ah_capabilities.cap_mode)) {
		/* B mode */
		memcpy(sband->bitrates, &ath5k_rates[0],
		       sizeof(struct ieee80211_rate) * 4);
		sband->n_bitrates = 4;

		/* 5211 only supports B rates and uses 4bit rate codes
		 * (e.g normally we have 0x1B for 1M, but on 5211 we have 0x0B)
		 * fix them up here:
		 */
		if (ah->ah_version == AR5K_AR5211) {
			for (i = 0; i < 4; i++) {
				sband->bitrates[i].hw_value =
					sband->bitrates[i].hw_value & 0xF;
				sband->bitrates[i].hw_value_short =
					sband->bitrates[i].hw_value_short & 0xF;
			}
		}

		sband->channels = ah->channels;
		sband->n_channels = ath5k_setup_channels(ah, sband->channels,
					AR5K_MODE_11B, max_c);

		hw->wiphy->bands[IEEE80211_BAND_2GHZ] = sband;
		count_c = sband->n_channels;
		max_c -= count_c;
	}
	ath5k_setup_rate_idx(ah, sband);

	/* 5GHz band, A mode */
	if (test_bit(AR5K_MODE_11A, ah->ah_capabilities.cap_mode)) {
		sband = &ah->sbands[IEEE80211_BAND_5GHZ];
		sband->band = IEEE80211_BAND_5GHZ;
		sband->bitrates = &ah->rates[IEEE80211_BAND_5GHZ][0];

		memcpy(sband->bitrates, &ath5k_rates[4],
		       sizeof(struct ieee80211_rate) * 8);
		sband->n_bitrates = 8;

		sband->channels = &ah->channels[count_c];
		sband->n_channels = ath5k_setup_channels(ah, sband->channels,
					AR5K_MODE_11A, max_c);

		hw->wiphy->bands[IEEE80211_BAND_5GHZ] = sband;
	}
	ath5k_setup_rate_idx(ah, sband);

	ath5k_debug_dump_bands(ah);

	return 0;
}

/*
 * Set/change channels. We always reset the chip.
 * To accomplish this we must first cleanup any pending DMA,
 * then restart stuff after a la  ath5k_init.
 *
 * Called with ah->lock.
 */
int
ath5k_chan_set(struct ath5k_hw *ah, struct ieee80211_channel *chan)
{
	ATH5K_DBG(ah, ATH5K_DEBUG_RESET,
		  "channel set, resetting (%u -> %u MHz)\n",
		  ah->curchan->center_freq, chan->center_freq);

	/*
	 * To switch channels clear any pending DMA operations;
	 * wait long enough for the RX fifo to drain, reset the
	 * hardware at the new frequency, and then re-enable
	 * the relevant bits of the h/w.
	 */
	return ath5k_reset(ah, chan, true);
}

void ath5k_vif_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
{
	struct ath5k_vif_iter_data *iter_data = data;
	int i;
	struct ath5k_vif *avf = (void *)vif->drv_priv;

	if (iter_data->hw_macaddr)
		for (i = 0; i < ETH_ALEN; i++)
			iter_data->mask[i] &=
				~(iter_data->hw_macaddr[i] ^ mac[i]);

	if (!iter_data->found_active) {
		iter_data->found_active = true;
		memcpy(iter_data->active_mac, mac, ETH_ALEN);
	}

	if (iter_data->need_set_hw_addr && iter_data->hw_macaddr)
		if (compare_ether_addr(iter_data->hw_macaddr, mac) == 0)
			iter_data->need_set_hw_addr = false;

	if (!iter_data->any_assoc) {
		if (avf->assoc)
			iter_data->any_assoc = true;
	}

	/* Calculate combined mode - when APs are active, operate in AP mode.
	 * Otherwise use the mode of the new interface. This can currently
	 * only deal with combinations of APs and STAs. Only one ad-hoc
	 * interfaces is allowed.
	 */
	if (avf->opmode == NL80211_IFTYPE_AP)
		iter_data->opmode = NL80211_IFTYPE_AP;
	else {
		if (avf->opmode == NL80211_IFTYPE_STATION)
			iter_data->n_stas++;
		if (iter_data->opmode == NL80211_IFTYPE_UNSPECIFIED)
			iter_data->opmode = avf->opmode;
	}
}

void
ath5k_update_bssid_mask_and_opmode(struct ath5k_hw *ah,
				   struct ieee80211_vif *vif)
{
	struct ath_common *common = ath5k_hw_common(ah);
	struct ath5k_vif_iter_data iter_data;
	u32 rfilt;

	/*
	 * Use the hardware MAC address as reference, the hardware uses it
	 * together with the BSSID mask when matching addresses.
	 */
	iter_data.hw_macaddr = common->macaddr;
	memset(&iter_data.mask, 0xff, ETH_ALEN);
	iter_data.found_active = false;
	iter_data.need_set_hw_addr = true;
	iter_data.opmode = NL80211_IFTYPE_UNSPECIFIED;
	iter_data.n_stas = 0;

	if (vif)
		ath5k_vif_iter(&iter_data, vif->addr, vif);

	/* Get list of all active MAC addresses */
	ieee80211_iterate_active_interfaces_atomic(ah->hw, ath5k_vif_iter,
						   &iter_data);
	memcpy(ah->bssidmask, iter_data.mask, ETH_ALEN);

	ah->opmode = iter_data.opmode;
	if (ah->opmode == NL80211_IFTYPE_UNSPECIFIED)
		/* Nothing active, default to station mode */
		ah->opmode = NL80211_IFTYPE_STATION;

	ath5k_hw_set_opmode(ah, ah->opmode);
	ATH5K_DBG(ah, ATH5K_DEBUG_MODE, "mode setup opmode %d (%s)\n",
		  ah->opmode, ath_opmode_to_string(ah->opmode));

	if (iter_data.need_set_hw_addr && iter_data.found_active)
		ath5k_hw_set_lladdr(ah, iter_data.active_mac);

	if (ath5k_hw_hasbssidmask(ah))
		ath5k_hw_set_bssid_mask(ah, ah->bssidmask);

	/* Set up RX Filter */
	if (iter_data.n_stas > 1) {
		/* If you have multiple STA interfaces connected to
		 * different APs, ARPs are not received (most of the time?)
		 * Enabling PROMISC appears to fix that problem.
		 */
		ah->filter_flags |= AR5K_RX_FILTER_PROM;
	}

	rfilt = ah->filter_flags;
	ath5k_hw_set_rx_filter(ah, rfilt);
	ATH5K_DBG(ah, ATH5K_DEBUG_MODE, "RX filter 0x%x\n", rfilt);
}

static inline int
ath5k_hw_to_driver_rix(struct ath5k_hw *ah, int hw_rix)
{
	int rix;

	/* return base rate on errors */
	if (WARN(hw_rix < 0 || hw_rix >= AR5K_MAX_RATES,
			"hw_rix out of bounds: %x\n", hw_rix))
		return 0;

	rix = ah->rate_idx[ah->curchan->band][hw_rix];
	if (WARN(rix < 0, "invalid hw_rix: %x\n", hw_rix))
		rix = 0;

	return rix;
}

/***************\
* Buffers setup *
\***************/

static
struct sk_buff *ath5k_rx_skb_alloc(struct ath5k_hw *ah, dma_addr_t *skb_addr)
{
	struct ath_common *common = ath5k_hw_common(ah);
	struct sk_buff *skb;

	/*
	 * Allocate buffer with headroom_needed space for the
	 * fake physical layer header at the start.
	 */
	skb = ath_rxbuf_alloc(common,
			      common->rx_bufsize,
			      GFP_ATOMIC);

	if (!skb) {
		ATH5K_ERR(ah, "can't alloc skbuff of size %u\n",
				common->rx_bufsize);
		return NULL;
	}

	*skb_addr = dma_map_single(ah->dev,
				   skb->data, common->rx_bufsize,
				   DMA_FROM_DEVICE);

	if (unlikely(dma_mapping_error(ah->dev, *skb_addr))) {
		ATH5K_ERR(ah, "%s: DMA mapping failed\n", __func__);
		dev_kfree_skb(skb);
		return NULL;
	}
	return skb;
}

static int
ath5k_rxbuf_setup(struct ath5k_hw *ah, struct ath5k_buf *bf)
{
	struct sk_buff *skb = bf->skb;
	struct ath5k_desc *ds;
	int ret;

	if (!skb) {
		skb = ath5k_rx_skb_alloc(ah, &bf->skbaddr);
		if (!skb)
			return -ENOMEM;
		bf->skb = skb;
	}

	/*
	 * Setup descriptors.  For receive we always terminate
	 * the descriptor list with a self-linked entry so we'll
	 * not get overrun under high load (as can happen with a
	 * 5212 when ANI processing enables PHY error frames).
	 *
	 * To ensure the last descriptor is self-linked we create
	 * each descriptor as self-linked and add it to the end.  As
	 * each additional descriptor is added the previous self-linked
	 * entry is "fixed" naturally.  This should be safe even
	 * if DMA is happening.  When processing RX interrupts we
	 * never remove/process the last, self-linked, entry on the
	 * descriptor list.  This ensures the hardware always has
	 * someplace to write a new frame.
	 */
	ds = bf->desc;
	ds->ds_link = bf->daddr;	/* link to self */
	ds->ds_data = bf->skbaddr;
	ret = ath5k_hw_setup_rx_desc(ah, ds, ah->common.rx_bufsize, 0);
	if (ret) {
		ATH5K_ERR(ah, "%s: could not setup RX desc\n", __func__);
		return ret;
	}

	if (ah->rxlink != NULL)
		*ah->rxlink = bf->daddr;
	ah->rxlink = &ds->ds_link;
	return 0;
}

static enum ath5k_pkt_type get_hw_packet_type(struct sk_buff *skb)
{
	struct ieee80211_hdr *hdr;
	enum ath5k_pkt_type htype;
	__le16 fc;

	hdr = (struct ieee80211_hdr *)skb->data;
	fc = hdr->frame_control;

	if (ieee80211_is_beacon(fc))
		htype = AR5K_PKT_TYPE_BEACON;
	else if (ieee80211_is_probe_resp(fc))
		htype = AR5K_PKT_TYPE_PROBE_RESP;
	else if (ieee80211_is_atim(fc))
		htype = AR5K_PKT_TYPE_ATIM;
	else if (ieee80211_is_pspoll(fc))
		htype = AR5K_PKT_TYPE_PSPOLL;
	else
		htype = AR5K_PKT_TYPE_NORMAL;

	return htype;
}

static int
ath5k_txbuf_setup(struct ath5k_hw *ah, struct ath5k_buf *bf,
		  struct ath5k_txq *txq, int padsize)
{
	struct ath5k_desc *ds = bf->desc;
	struct sk_buff *skb = bf->skb;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	unsigned int pktlen, flags, keyidx = AR5K_TXKEYIX_INVALID;
	struct ieee80211_rate *rate;
	unsigned int mrr_rate[3], mrr_tries[3];
	int i, ret;
	u16 hw_rate;
	u16 cts_rate = 0;
	u16 duration = 0;
	u8 rc_flags;

	flags = AR5K_TXDESC_INTREQ | AR5K_TXDESC_CLRDMASK;

	/* XXX endianness */
	bf->skbaddr = dma_map_single(ah->dev, skb->data, skb->len,
			DMA_TO_DEVICE);

	rate = ieee80211_get_tx_rate(ah->hw, info);
	if (!rate) {
		ret = -EINVAL;
		goto err_unmap;
	}

	if (info->flags & IEEE80211_TX_CTL_NO_ACK)
		flags |= AR5K_TXDESC_NOACK;

	rc_flags = info->control.rates[0].flags;
	hw_rate = (rc_flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE) ?
		rate->hw_value_short : rate->hw_value;

	pktlen = skb->len;

	/* FIXME: If we are in g mode and rate is a CCK rate
	 * subtract ah->ah_txpower.txp_cck_ofdm_pwr_delta
	 * from tx power (value is in dB units already) */
	if (info->control.hw_key) {
		keyidx = info->control.hw_key->hw_key_idx;
		pktlen += info->control.hw_key->icv_len;
	}
	if (rc_flags & IEEE80211_TX_RC_USE_RTS_CTS) {
		flags |= AR5K_TXDESC_RTSENA;
		cts_rate = ieee80211_get_rts_cts_rate(ah->hw, info)->hw_value;
		duration = le16_to_cpu(ieee80211_rts_duration(ah->hw,
			info->control.vif, pktlen, info));
	}
	if (rc_flags & IEEE80211_TX_RC_USE_CTS_PROTECT) {
		flags |= AR5K_TXDESC_CTSENA;
		cts_rate = ieee80211_get_rts_cts_rate(ah->hw, info)->hw_value;
		duration = le16_to_cpu(ieee80211_ctstoself_duration(ah->hw,
			info->control.vif, pktlen, info));
	}
	ret = ah->ah_setup_tx_desc(ah, ds, pktlen,
		ieee80211_get_hdrlen_from_skb(skb), padsize,
		get_hw_packet_type(skb),
		(ah->power_level * 2),
		hw_rate,
		info->control.rates[0].count, keyidx, ah->ah_tx_ant, flags,
		cts_rate, duration);
	if (ret)
		goto err_unmap;

	/* Set up MRR descriptor */
	if (ah->ah_capabilities.cap_has_mrr_support) {
		memset(mrr_rate, 0, sizeof(mrr_rate));
		memset(mrr_tries, 0, sizeof(mrr_tries));
		for (i = 0; i < 3; i++) {
			rate = ieee80211_get_alt_retry_rate(ah->hw, info, i);
			if (!rate)
				break;

			mrr_rate[i] = rate->hw_value;
			mrr_tries[i] = info->control.rates[i + 1].count;
		}

		ath5k_hw_setup_mrr_tx_desc(ah, ds,
			mrr_rate[0], mrr_tries[0],
			mrr_rate[1], mrr_tries[1],
			mrr_rate[2], mrr_tries[2]);
	}

	ds->ds_link = 0;
	ds->ds_data = bf->skbaddr;

	spin_lock_bh(&txq->lock);
	list_add_tail(&bf->list, &txq->q);
	txq->txq_len++;
	if (txq->link == NULL) /* is this first packet? */
		ath5k_hw_set_txdp(ah, txq->qnum, bf->daddr);
	else /* no, so only link it */
		*txq->link = bf->daddr;

	txq->link = &ds->ds_link;
	ath5k_hw_start_tx_dma(ah, txq->qnum);
	mmiowb();
	spin_unlock_bh(&txq->lock);

	return 0;
err_unmap:
	dma_unmap_single(ah->dev, bf->skbaddr, skb->len, DMA_TO_DEVICE);
	return ret;
}

/*******************\
* Descriptors setup *
\*******************/

static int
ath5k_desc_alloc(struct ath5k_hw *ah)
{
	struct ath5k_desc *ds;
	struct ath5k_buf *bf;
	dma_addr_t da;
	unsigned int i;
	int ret;

	/* allocate descriptors */
	ah->desc_len = sizeof(struct ath5k_desc) *
			(ATH_TXBUF + ATH_RXBUF + ATH_BCBUF + 1);

	ah->desc = dma_alloc_coherent(ah->dev, ah->desc_len,
				&ah->desc_daddr, GFP_KERNEL);
	if (ah->desc == NULL) {
		ATH5K_ERR(ah, "can't allocate descriptors\n");
		ret = -ENOMEM;
		goto err;
	}
	ds = ah->desc;
	da = ah->desc_daddr;
	ATH5K_DBG(ah, ATH5K_DEBUG_ANY, "DMA map: %p (%zu) -> %llx\n",
		ds, ah->desc_len, (unsigned long long)ah->desc_daddr);

	bf = kcalloc(1 + ATH_TXBUF + ATH_RXBUF + ATH_BCBUF,
			sizeof(struct ath5k_buf), GFP_KERNEL);
	if (bf == NULL) {
		ATH5K_ERR(ah, "can't allocate bufptr\n");
		ret = -ENOMEM;
		goto err_free;
	}
	ah->bufptr = bf;

	INIT_LIST_HEAD(&ah->rxbuf);
	for (i = 0; i < ATH_RXBUF; i++, bf++, ds++, da += sizeof(*ds)) {
		bf->desc = ds;
		bf->daddr = da;
		list_add_tail(&bf->list, &ah->rxbuf);
	}

	INIT_LIST_HEAD(&ah->txbuf);
	ah->txbuf_len = ATH_TXBUF;
	for (i = 0; i < ATH_TXBUF; i++, bf++, ds++, da += sizeof(*ds)) {
		bf->desc = ds;
		bf->daddr = da;
		list_add_tail(&bf->list, &ah->txbuf);
	}

	/* beacon buffers */
	INIT_LIST_HEAD(&ah->bcbuf);
	for (i = 0; i < ATH_BCBUF; i++, bf++, ds++, da += sizeof(*ds)) {
		bf->desc = ds;
		bf->daddr = da;
		list_add_tail(&bf->list, &ah->bcbuf);
	}

	return 0;
err_free:
	dma_free_coherent(ah->dev, ah->desc_len, ah->desc, ah->desc_daddr);
err:
	ah->desc = NULL;
	return ret;
}

void
ath5k_txbuf_free_skb(struct ath5k_hw *ah, struct ath5k_buf *bf)
{
	BUG_ON(!bf);
	if (!bf->skb)
		return;
	dma_unmap_single(ah->dev, bf->skbaddr, bf->skb->len,
			DMA_TO_DEVICE);
	dev_kfree_skb_any(bf->skb);
	bf->skb = NULL;
	bf->skbaddr = 0;
	bf->desc->ds_data = 0;
}

void
ath5k_rxbuf_free_skb(struct ath5k_hw *ah, struct ath5k_buf *bf)
{
	struct ath_common *common = ath5k_hw_common(ah);

	BUG_ON(!bf);
	if (!bf->skb)
		return;
	dma_unmap_single(ah->dev, bf->skbaddr, common->rx_bufsize,
			DMA_FROM_DEVICE);
	dev_kfree_skb_any(bf->skb);
	bf->skb = NULL;
	bf->skbaddr = 0;
	bf->desc->ds_data = 0;
}

static void
ath5k_desc_free(struct ath5k_hw *ah)
{
	struct ath5k_buf *bf;

	list_for_each_entry(bf, &ah->txbuf, list)
		ath5k_txbuf_free_skb(ah, bf);
	list_for_each_entry(bf, &ah->rxbuf, list)
		ath5k_rxbuf_free_skb(ah, bf);
	list_for_each_entry(bf, &ah->bcbuf, list)
		ath5k_txbuf_free_skb(ah, bf);

	/* Free memory associated with all descriptors */
	dma_free_coherent(ah->dev, ah->desc_len, ah->desc, ah->desc_daddr);
	ah->desc = NULL;
	ah->desc_daddr = 0;

	kfree(ah->bufptr);
	ah->bufptr = NULL;
}


/**************\
* Queues setup *
\**************/

static struct ath5k_txq *
ath5k_txq_setup(struct ath5k_hw *ah,
		int qtype, int subtype)
{
	struct ath5k_txq *txq;
	struct ath5k_txq_info qi = {
		.tqi_subtype = subtype,
		/* XXX: default values not correct for B and XR channels,
		 * but who cares? */
		.tqi_aifs = AR5K_TUNE_AIFS,
		.tqi_cw_min = AR5K_TUNE_CWMIN,
		.tqi_cw_max = AR5K_TUNE_CWMAX
	};
	int qnum;

	/*
	 * Enable interrupts only for EOL and DESC conditions.
	 * We mark tx descriptors to receive a DESC interrupt
	 * when a tx queue gets deep; otherwise we wait for the
	 * EOL to reap descriptors.  Note that this is done to
	 * reduce interrupt load and this only defers reaping
	 * descriptors, never transmitting frames.  Aside from
	 * reducing interrupts this also permits more concurrency.
	 * The only potential downside is if the tx queue backs
	 * up in which case the top half of the kernel may backup
	 * due to a lack of tx descriptors.
	 */
	qi.tqi_flags = AR5K_TXQ_FLAG_TXEOLINT_ENABLE |
				AR5K_TXQ_FLAG_TXDESCINT_ENABLE;
	qnum = ath5k_hw_setup_tx_queue(ah, qtype, &qi);
	if (qnum < 0) {
		/*
		 * NB: don't print a message, this happens
		 * normally on parts with too few tx queues
		 */
		return ERR_PTR(qnum);
	}
	txq = &ah->txqs[qnum];
	if (!txq->setup) {
		txq->qnum = qnum;
		txq->link = NULL;
		INIT_LIST_HEAD(&txq->q);
		spin_lock_init(&txq->lock);
		txq->setup = true;
		txq->txq_len = 0;
		txq->txq_max = ATH5K_TXQ_LEN_MAX;
		txq->txq_poll_mark = false;
		txq->txq_stuck = 0;
	}
	return &ah->txqs[qnum];
}

static int
ath5k_beaconq_setup(struct ath5k_hw *ah)
{
	struct ath5k_txq_info qi = {
		/* XXX: default values not correct for B and XR channels,
		 * but who cares? */
		.tqi_aifs = AR5K_TUNE_AIFS,
		.tqi_cw_min = AR5K_TUNE_CWMIN,
		.tqi_cw_max = AR5K_TUNE_CWMAX,
		/* NB: for dynamic turbo, don't enable any other interrupts */
		.tqi_flags = AR5K_TXQ_FLAG_TXDESCINT_ENABLE
	};

	return ath5k_hw_setup_tx_queue(ah, AR5K_TX_QUEUE_BEACON, &qi);
}

static int
ath5k_beaconq_config(struct ath5k_hw *ah)
{
	struct ath5k_txq_info qi;
	int ret;

	ret = ath5k_hw_get_tx_queueprops(ah, ah->bhalq, &qi);
	if (ret)
		goto err;

	if (ah->opmode == NL80211_IFTYPE_AP ||
	    ah->opmode == NL80211_IFTYPE_MESH_POINT) {
		/*
		 * Always burst out beacon and CAB traffic
		 * (aifs = cwmin = cwmax = 0)
		 */
		qi.tqi_aifs = 0;
		qi.tqi_cw_min = 0;
		qi.tqi_cw_max = 0;
	} else if (ah->opmode == NL80211_IFTYPE_ADHOC) {
		/*
		 * Adhoc mode; backoff between 0 and (2 * cw_min).
		 */
		qi.tqi_aifs = 0;
		qi.tqi_cw_min = 0;
		qi.tqi_cw_max = 2 * AR5K_TUNE_CWMIN;
	}

	ATH5K_DBG(ah, ATH5K_DEBUG_BEACON,
		"beacon queueprops tqi_aifs:%d tqi_cw_min:%d tqi_cw_max:%d\n",
		qi.tqi_aifs, qi.tqi_cw_min, qi.tqi_cw_max);

	ret = ath5k_hw_set_tx_queueprops(ah, ah->bhalq, &qi);
	if (ret) {