Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1011 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/ath5k/pcu.c b/drivers/net/wireless/ath/ath5k/pcu.c
new file mode 100644
index 000000000..05140d8ba
--- /dev/null
+++ b/drivers/net/wireless/ath/ath5k/pcu.c
@@ -0,0 +1,1011 @@
+/*
+ * Copyright (c) 2004-2008 Reyk Floeter <reyk@openbsd.org>
+ * Copyright (c) 2006-2008 Nick Kossifidis <mickflemm@gmail.com>
+ * Copyright (c) 2007-2008 Matthew W. S. Bell  <mentor@madwifi.org>
+ * Copyright (c) 2007-2008 Luis Rodriguez <mcgrof@winlab.rutgers.edu>
+ * Copyright (c) 2007-2008 Pavel Roskin <proski@gnu.org>
+ * Copyright (c) 2007-2008 Jiri Slaby <jirislaby@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+/*********************************\
+* Protocol Control Unit Functions *
+\*********************************/
+
+#include <asm/unaligned.h>
+
+#include "ath5k.h"
+#include "reg.h"
+#include "debug.h"
+
+/**
+ * DOC: Protocol Control Unit (PCU) functions
+ *
+ * Protocol control unit is responsible to maintain various protocol
+ * properties before a frame is send and after a frame is received to/from
+ * baseband. To be more specific, PCU handles:
+ *
+ * - Buffering of RX and TX frames (after QCU/DCUs)
+ *
+ * - Encrypting and decrypting (using the built-in engine)
+ *
+ * - Generating ACKs, RTS/CTS frames
+ *
+ * - Maintaining TSF
+ *
+ * - FCS
+ *
+ * - Updating beacon data (with TSF etc)
+ *
+ * - Generating virtual CCA
+ *
+ * - RX/Multicast filtering
+ *
+ * - BSSID filtering
+ *
+ * - Various statistics
+ *
+ * -Different operating modes: AP, STA, IBSS
+ *
+ * Note: Most of these functions can be tweaked/bypassed so you can do
+ * them on sw above for debugging or research. For more infos check out PCU
+ * registers on reg.h.
+ */
+
+/**
+ * DOC: ACK rates
+ *
+ * AR5212+ can use higher rates for ack transmission
+ * based on current tx rate instead of the base rate.
+ * It does this to better utilize channel usage.
+ * There is a mapping between G rates (that cover both
+ * CCK and OFDM) and ack rates that we use when setting
+ * rate -> duration table. This mapping is hw-based so
+ * don't change anything.
+ *
+ * To enable this functionality we must set
+ * ah->ah_ack_bitrate_high to true else base rate is
+ * used (1Mb for CCK, 6Mb for OFDM).
+ */
+static const unsigned int ack_rates_high[] =
+/* Tx	-> ACK	*/
+/* 1Mb	-> 1Mb	*/	{ 0,
+/* 2MB	-> 2Mb	*/	1,
+/* 5.5Mb -> 2Mb	*/	1,
+/* 11Mb	-> 2Mb	*/	1,
+/* 6Mb	-> 6Mb	*/	4,
+/* 9Mb	-> 6Mb	*/	4,
+/* 12Mb	-> 12Mb	*/	6,
+/* 18Mb	-> 12Mb	*/	6,
+/* 24Mb	-> 24Mb	*/	8,
+/* 36Mb	-> 24Mb	*/	8,
+/* 48Mb	-> 24Mb	*/	8,
+/* 54Mb	-> 24Mb	*/	8 };
+
+/*******************\
+* Helper functions *
+\*******************/
+
+/**
+ * ath5k_hw_get_frame_duration() - Get tx time of a frame
+ * @ah: The &struct ath5k_hw
+ * @len: Frame's length in bytes
+ * @rate: The @struct ieee80211_rate
+ * @shortpre: Indicate short preample
+ *
+ * Calculate tx duration of a frame given it's rate and length
+ * It extends ieee80211_generic_frame_duration for non standard
+ * bwmodes.
+ */
+int
+ath5k_hw_get_frame_duration(struct ath5k_hw *ah, enum nl80211_band band,
+		int len, struct ieee80211_rate *rate, bool shortpre)
+{
+	int sifs, preamble, plcp_bits, sym_time;
+	int bitrate, bits, symbols, symbol_bits;
+	int dur;
+
+	/* Fallback */
+	if (!ah->ah_bwmode) {
+		__le16 raw_dur = ieee80211_generic_frame_duration(ah->hw,
+					NULL, band, len, rate);
+
+		/* subtract difference between long and short preamble */
+		dur = le16_to_cpu(raw_dur);
+		if (shortpre)
+			dur -= 96;
+
+		return dur;
+	}
+
+	bitrate = rate->bitrate;
+	preamble = AR5K_INIT_OFDM_PREAMPLE_TIME;
+	plcp_bits = AR5K_INIT_OFDM_PLCP_BITS;
+	sym_time = AR5K_INIT_OFDM_SYMBOL_TIME;
+
+	switch (ah->ah_bwmode) {
+	case AR5K_BWMODE_40MHZ:
+		sifs = AR5K_INIT_SIFS_TURBO;
+		preamble = AR5K_INIT_OFDM_PREAMBLE_TIME_MIN;
+		break;
+	case AR5K_BWMODE_10MHZ:
+		sifs = AR5K_INIT_SIFS_HALF_RATE;
+		preamble *= 2;
+		sym_time *= 2;
+		bitrate = DIV_ROUND_UP(bitrate, 2);
+		break;
+	case AR5K_BWMODE_5MHZ:
+		sifs = AR5K_INIT_SIFS_QUARTER_RATE;
+		preamble *= 4;
+		sym_time *= 4;
+		bitrate = DIV_ROUND_UP(bitrate, 4);
+		break;
+	default:
+		sifs = AR5K_INIT_SIFS_DEFAULT_BG;
+		break;
+	}
+
+	bits = plcp_bits + (len << 3);
+	/* Bit rate is in 100Kbits */
+	symbol_bits = bitrate * sym_time;
+	symbols = DIV_ROUND_UP(bits * 10, symbol_bits);
+
+	dur = sifs + preamble + (sym_time * symbols);
+
+	return dur;
+}
+
+/**
+ * ath5k_hw_get_default_slottime() - Get the default slot time for current mode
+ * @ah: The &struct ath5k_hw
+ */
+unsigned int
+ath5k_hw_get_default_slottime(struct ath5k_hw *ah)
+{
+	struct ieee80211_channel *channel = ah->ah_current_channel;
+	unsigned int slot_time;
+
+	switch (ah->ah_bwmode) {
+	case AR5K_BWMODE_40MHZ:
+		slot_time = AR5K_INIT_SLOT_TIME_TURBO;
+		break;
+	case AR5K_BWMODE_10MHZ:
+		slot_time = AR5K_INIT_SLOT_TIME_HALF_RATE;
+		break;
+	case AR5K_BWMODE_5MHZ:
+		slot_time = AR5K_INIT_SLOT_TIME_QUARTER_RATE;
+		break;
+	case AR5K_BWMODE_DEFAULT:
+	default:
+		slot_time = AR5K_INIT_SLOT_TIME_DEFAULT;
+		if ((channel->hw_value == AR5K_MODE_11B) && !ah->ah_short_slot)
+			slot_time = AR5K_INIT_SLOT_TIME_B;
+		break;
+	}
+
+	return slot_time;
+}
+
+/**
+ * ath5k_hw_get_default_sifs() - Get the default SIFS for current mode
+ * @ah: The &struct ath5k_hw
+ */
+unsigned int
+ath5k_hw_get_default_sifs(struct ath5k_hw *ah)
+{
+	struct ieee80211_channel *channel = ah->ah_current_channel;
+	unsigned int sifs;
+
+	switch (ah->ah_bwmode) {
+	case AR5K_BWMODE_40MHZ:
+		sifs = AR5K_INIT_SIFS_TURBO;
+		break;
+	case AR5K_BWMODE_10MHZ:
+		sifs = AR5K_INIT_SIFS_HALF_RATE;
+		break;
+	case AR5K_BWMODE_5MHZ:
+		sifs = AR5K_INIT_SIFS_QUARTER_RATE;
+		break;
+	case AR5K_BWMODE_DEFAULT:
+	default:
+		sifs = AR5K_INIT_SIFS_DEFAULT_BG;
+		if (channel->band == NL80211_BAND_5GHZ)
+			sifs = AR5K_INIT_SIFS_DEFAULT_A;
+		break;
+	}
+
+	return sifs;
+}
+
+/**
+ * ath5k_hw_update_mib_counters() - Update MIB counters (mac layer statistics)
+ * @ah: The &struct ath5k_hw
+ *
+ * Reads MIB counters from PCU and updates sw statistics. Is called after a
+ * MIB interrupt, because one of these counters might have reached their maximum
+ * and triggered the MIB interrupt, to let us read and clear the counter.
+ *
+ * NOTE: Is called in interrupt context!
+ */
+void
+ath5k_hw_update_mib_counters(struct ath5k_hw *ah)
+{
+	struct ath5k_statistics *stats = &ah->stats;
+
+	/* Read-And-Clear */
+	stats->ack_fail += ath5k_hw_reg_read(ah, AR5K_ACK_FAIL);
+	stats->rts_fail += ath5k_hw_reg_read(ah, AR5K_RTS_FAIL);
+	stats->rts_ok += ath5k_hw_reg_read(ah, AR5K_RTS_OK);
+	stats->fcs_error += ath5k_hw_reg_read(ah, AR5K_FCS_FAIL);
+	stats->beacons += ath5k_hw_reg_read(ah, AR5K_BEACON_CNT);
+}
+
+
+/******************\
+* ACK/CTS Timeouts *
+\******************/
+
+/**
+ * ath5k_hw_write_rate_duration() - Fill rate code to duration table
+ * @ah: The &struct ath5k_hw
+ *
+ * Write the rate code to duration table upon hw reset. This is a helper for
+ * ath5k_hw_pcu_init(). It seems all this is doing is setting an ACK timeout on
+ * the hardware, based on current mode, for each rate. The rates which are
+ * capable of short preamble (802.11b rates 2Mbps, 5.5Mbps, and 11Mbps) have
+ * different rate code so we write their value twice (one for long preamble
+ * and one for short).
+ *
+ * Note: Band doesn't matter here, if we set the values for OFDM it works
+ * on both a and g modes. So all we have to do is set values for all g rates
+ * that include all OFDM and CCK rates.
+ *
+ */
+static inline void
+ath5k_hw_write_rate_duration(struct ath5k_hw *ah)
+{
+	struct ieee80211_rate *rate;
+	unsigned int i;
+	/* 802.11g covers both OFDM and CCK */
+	u8 band = NL80211_BAND_2GHZ;
+
+	/* Write rate duration table */
+	for (i = 0; i < ah->sbands[band].n_bitrates; i++) {
+		u32 reg;
+		u16 tx_time;
+
+		if (ah->ah_ack_bitrate_high)
+			rate = &ah->sbands[band].bitrates[ack_rates_high[i]];
+		/* CCK -> 1Mb */
+		else if (i < 4)
+			rate = &ah->sbands[band].bitrates[0];
+		/* OFDM -> 6Mb */
+		else
+			rate = &ah->sbands[band].bitrates[4];
+
+		/* Set ACK timeout */
+		reg = AR5K_RATE_DUR(rate->hw_value);
+
+		/* An ACK frame consists of 10 bytes. If you add the FCS,
+		 * which ieee80211_generic_frame_duration() adds,
+		 * its 14 bytes. Note we use the control rate and not the
+		 * actual rate for this rate. See mac80211 tx.c
+		 * ieee80211_duration() for a brief description of
+		 * what rate we should choose to TX ACKs. */
+		tx_time = ath5k_hw_get_frame_duration(ah, band, 10,
+					rate, false);
+
+		ath5k_hw_reg_write(ah, tx_time, reg);
+
+		if (!(rate->flags & IEEE80211_RATE_SHORT_PREAMBLE))
+			continue;
+
+		tx_time = ath5k_hw_get_frame_duration(ah, band, 10, rate, true);
+		ath5k_hw_reg_write(ah, tx_time,
+			reg + (AR5K_SET_SHORT_PREAMBLE << 2));
+	}
+}
+
+/**
+ * ath5k_hw_set_ack_timeout() - Set ACK timeout on PCU
+ * @ah: The &struct ath5k_hw
+ * @timeout: Timeout in usec
+ */
+static int
+ath5k_hw_set_ack_timeout(struct ath5k_hw *ah, unsigned int timeout)
+{
+	if (ath5k_hw_clocktoh(ah, AR5K_REG_MS(0xffffffff, AR5K_TIME_OUT_ACK))
+			<= timeout)
+		return -EINVAL;
+
+	AR5K_REG_WRITE_BITS(ah, AR5K_TIME_OUT, AR5K_TIME_OUT_ACK,
+		ath5k_hw_htoclock(ah, timeout));
+
+	return 0;
+}
+
+/**
+ * ath5k_hw_set_cts_timeout() - Set CTS timeout on PCU
+ * @ah: The &struct ath5k_hw
+ * @timeout: Timeout in usec
+ */
+static int
+ath5k_hw_set_cts_timeout(struct ath5k_hw *ah, unsigned int timeout)
+{
+	if (ath5k_hw_clocktoh(ah, AR5K_REG_MS(0xffffffff, AR5K_TIME_OUT_CTS))
+			<= timeout)
+		return -EINVAL;
+
+	AR5K_REG_WRITE_BITS(ah, AR5K_TIME_OUT, AR5K_TIME_OUT_CTS,
+			ath5k_hw_htoclock(ah, timeout));
+
+	return 0;
+}
+
+
+/*******************\
+* RX filter Control *
+\*******************/
+
+/**
+ * ath5k_hw_set_lladdr() - Set station id
+ * @ah: The &struct ath5k_hw
+ * @mac: The card's mac address (array of octets)
+ *
+ * Set station id on hw using the provided mac address
+ */
+int
+ath5k_hw_set_lladdr(struct ath5k_hw *ah, const u8 *mac)
+{
+	struct ath_common *common = ath5k_hw_common(ah);
+	u32 low_id, high_id;
+	u32 pcu_reg;
+
+	/* Set new station ID */
+	memcpy(common->macaddr, mac, ETH_ALEN);
+
+	pcu_reg = ath5k_hw_reg_read(ah, AR5K_STA_ID1) & 0xffff0000;
+
+	low_id = get_unaligned_le32(mac);
+	high_id = get_unaligned_le16(mac + 4);
+
+	ath5k_hw_reg_write(ah, low_id, AR5K_STA_ID0);
+	ath5k_hw_reg_write(ah, pcu_reg | high_id, AR5K_STA_ID1);
+
+	return 0;
+}
+
+/**
+ * ath5k_hw_set_bssid() - Set current BSSID on hw
+ * @ah: The &struct ath5k_hw
+ *
+ * Sets the current BSSID and BSSID mask we have from the
+ * common struct into the hardware
+ */
+void
+ath5k_hw_set_bssid(struct ath5k_hw *ah)
+{
+	struct ath_common *common = ath5k_hw_common(ah);
+	u16 tim_offset = 0;
+
+	/*
+	 * Set BSSID mask on 5212
+	 */
+	if (ah->ah_version == AR5K_AR5212)
+		ath_hw_setbssidmask(common);
+
+	/*
+	 * Set BSSID
+	 */
+	ath5k_hw_reg_write(ah,
+			   get_unaligned_le32(common->curbssid),
+			   AR5K_BSS_ID0);
+	ath5k_hw_reg_write(ah,
+			   get_unaligned_le16(common->curbssid + 4) |
+			   ((common->curaid & 0x3fff) << AR5K_BSS_ID1_AID_S),
+			   AR5K_BSS_ID1);
+
+	if (common->curaid == 0) {
+		ath5k_hw_disable_pspoll(ah);
+		return;
+	}
+
+	AR5K_REG_WRITE_BITS(ah, AR5K_BEACON, AR5K_BEACON_TIM,
+			    tim_offset ? tim_offset + 4 : 0);
+
+	ath5k_hw_enable_pspoll(ah, NULL, 0);
+}
+
+/**
+ * ath5k_hw_set_bssid_mask() - Filter out bssids we listen
+ * @ah: The &struct ath5k_hw
+ * @mask: The BSSID mask to set (array of octets)
+ *
+ * BSSID masking is a method used by AR5212 and newer hardware to inform PCU
+ * which bits of the interface's MAC address should be looked at when trying
+ * to decide which packets to ACK. In station mode and AP mode with a single
+ * BSS every bit matters since we lock to only one BSS. In AP mode with
+ * multiple BSSes (virtual interfaces) not every bit matters because hw must
+ * accept frames for all BSSes and so we tweak some bits of our mac address
+ * in order to have multiple BSSes.
+ *
+ * For more information check out ../hw.c of the common ath module.
+ */
+void
+ath5k_hw_set_bssid_mask(struct ath5k_hw *ah, const u8 *mask)
+{
+	struct ath_common *common = ath5k_hw_common(ah);
+
+	/* Cache bssid mask so that we can restore it
+	 * on reset */
+	memcpy(common->bssidmask, mask, ETH_ALEN);
+	if (ah->ah_version == AR5K_AR5212)
+		ath_hw_setbssidmask(common);
+}
+
+/**
+ * ath5k_hw_set_mcast_filter() - Set multicast filter
+ * @ah: The &struct ath5k_hw
+ * @filter0: Lower 32bits of muticast filter
+ * @filter1: Higher 16bits of multicast filter
+ */
+void
+ath5k_hw_set_mcast_filter(struct ath5k_hw *ah, u32 filter0, u32 filter1)
+{
+	ath5k_hw_reg_write(ah, filter0, AR5K_MCAST_FILTER0);
+	ath5k_hw_reg_write(ah, filter1, AR5K_MCAST_FILTER1);
+}
+
+/**
+ * ath5k_hw_get_rx_filter() - Get current rx filter
+ * @ah: The &struct ath5k_hw
+ *
+ * Returns the RX filter by reading rx filter and
+ * phy error filter registers. RX filter is used
+ * to set the allowed frame types that PCU will accept
+ * and pass to the driver. For a list of frame types
+ * check out reg.h.
+ */
+u32
+ath5k_hw_get_rx_filter(struct ath5k_hw *ah)
+{
+	u32 data, filter = 0;
+
+	filter = ath5k_hw_reg_read(ah, AR5K_RX_FILTER);
+
+	/*Radar detection for 5212*/
+	if (ah->ah_version == AR5K_AR5212) {
+		data = ath5k_hw_reg_read(ah, AR5K_PHY_ERR_FIL);
+
+		if (data & AR5K_PHY_ERR_FIL_RADAR)
+			filter |= AR5K_RX_FILTER_RADARERR;
+		if (data & (AR5K_PHY_ERR_FIL_OFDM | AR5K_PHY_ERR_FIL_CCK))
+			filter |= AR5K_RX_FILTER_PHYERR;
+	}
+
+	return filter;
+}
+
+/**
+ * ath5k_hw_set_rx_filter() - Set rx filter
+ * @ah: The &struct ath5k_hw
+ * @filter: RX filter mask (see reg.h)
+ *
+ * Sets RX filter register and also handles PHY error filter
+ * register on 5212 and newer chips so that we have proper PHY
+ * error reporting.
+ */
+void
+ath5k_hw_set_rx_filter(struct ath5k_hw *ah, u32 filter)
+{
+	u32 data = 0;
+
+	/* Set PHY error filter register on 5212*/
+	if (ah->ah_version == AR5K_AR5212) {
+		if (filter & AR5K_RX_FILTER_RADARERR)
+			data |= AR5K_PHY_ERR_FIL_RADAR;
+		if (filter & AR5K_RX_FILTER_PHYERR)
+			data |= AR5K_PHY_ERR_FIL_OFDM | AR5K_PHY_ERR_FIL_CCK;
+	}
+
+	/*
+	 * The AR5210 uses promiscuous mode to detect radar activity
+	 */
+	if (ah->ah_version == AR5K_AR5210 &&
+			(filter & AR5K_RX_FILTER_RADARERR)) {
+		filter &= ~AR5K_RX_FILTER_RADARERR;
+		filter |= AR5K_RX_FILTER_PROM;
+	}
+
+	/*Zero length DMA (phy error reporting) */
+	if (data)
+		AR5K_REG_ENABLE_BITS(ah, AR5K_RXCFG, AR5K_RXCFG_ZLFDMA);
+	else
+		AR5K_REG_DISABLE_BITS(ah, AR5K_RXCFG, AR5K_RXCFG_ZLFDMA);
+
+	/*Write RX Filter register*/
+	ath5k_hw_reg_write(ah, filter & 0xff, AR5K_RX_FILTER);
+
+	/*Write PHY error filter register on 5212*/
+	if (ah->ah_version == AR5K_AR5212)
+		ath5k_hw_reg_write(ah, data, AR5K_PHY_ERR_FIL);
+
+}
+
+
+/****************\
+* Beacon control *
+\****************/
+
+#define ATH5K_MAX_TSF_READ 10
+
+/**
+ * ath5k_hw_get_tsf64() - Get the full 64bit TSF
+ * @ah: The &struct ath5k_hw
+ *
+ * Returns the current TSF
+ */
+u64
+ath5k_hw_get_tsf64(struct ath5k_hw *ah)
+{
+	u32 tsf_lower, tsf_upper1, tsf_upper2;
+	int i;
+	unsigned long flags;
+
+	/* This code is time critical - we don't want to be interrupted here */
+	local_irq_save(flags);
+
+	/*
+	 * While reading TSF upper and then lower part, the clock is still
+	 * counting (or jumping in case of IBSS merge) so we might get
+	 * inconsistent values. To avoid this, we read the upper part again
+	 * and check it has not been changed. We make the hypothesis that a
+	 * maximum of 3 changes can happens in a row (we use 10 as a safe
+	 * value).
+	 *
+	 * Impact on performance is pretty small, since in most cases, only
+	 * 3 register reads are needed.
+	 */
+
+	tsf_upper1 = ath5k_hw_reg_read(ah, AR5K_TSF_U32);
+	for (i = 0; i < ATH5K_MAX_TSF_READ; i++) {
+		tsf_lower = ath5k_hw_reg_read(ah, AR5K_TSF_L32);
+		tsf_upper2 = ath5k_hw_reg_read(ah, AR5K_TSF_U32);
+		if (tsf_upper2 == tsf_upper1)
+			break;
+		tsf_upper1 = tsf_upper2;
+	}
+
+	local_irq_restore(flags);
+
+	WARN_ON(i == ATH5K_MAX_TSF_READ);
+
+	return ((u64)tsf_upper1 << 32) | tsf_lower;
+}
+
+#undef ATH5K_MAX_TSF_READ
+
+/**
+ * ath5k_hw_set_tsf64() - Set a new 64bit TSF
+ * @ah: The &struct ath5k_hw
+ * @tsf64: The new 64bit TSF
+ *
+ * Sets the new TSF
+ */
+void
+ath5k_hw_set_tsf64(struct ath5k_hw *ah, u64 tsf64)
+{
+	ath5k_hw_reg_write(ah, tsf64 & 0xffffffff, AR5K_TSF_L32);
+	ath5k_hw_reg_write(ah, (tsf64 >> 32) & 0xffffffff, AR5K_TSF_U32);
+}
+
+/**
+ * ath5k_hw_reset_tsf() - Force a TSF reset
+ * @ah: The &struct ath5k_hw
+ *
+ * Forces a TSF reset on PCU
+ */
+void
+ath5k_hw_reset_tsf(struct ath5k_hw *ah)
+{
+	u32 val;
+
+	val = ath5k_hw_reg_read(ah, AR5K_BEACON) | AR5K_BEACON_RESET_TSF;
+
+	/*
+	 * Each write to the RESET_TSF bit toggles a hardware internal
+	 * signal to reset TSF, but if left high it will cause a TSF reset
+	 * on the next chip reset as well.  Thus we always write the value
+	 * twice to clear the signal.
+	 */
+	ath5k_hw_reg_write(ah, val, AR5K_BEACON);
+	ath5k_hw_reg_write(ah, val, AR5K_BEACON);
+}
+
+/**
+ * ath5k_hw_init_beacon_timers() - Initialize beacon timers
+ * @ah: The &struct ath5k_hw
+ * @next_beacon: Next TBTT
+ * @interval: Current beacon interval
+ *
+ * This function is used to initialize beacon timers based on current
+ * operation mode and settings.
+ */
+void
+ath5k_hw_init_beacon_timers(struct ath5k_hw *ah, u32 next_beacon, u32 interval)
+{
+	u32 timer1, timer2, timer3;
+
+	/*
+	 * Set the additional timers by mode
+	 */
+	switch (ah->opmode) {
+	case NL80211_IFTYPE_MONITOR:
+	case NL80211_IFTYPE_STATION:
+		/* In STA mode timer1 is used as next wakeup
+		 * timer and timer2 as next CFP duration start
+		 * timer. Both in 1/8TUs. */
+		/* TODO: PCF handling */
+		if (ah->ah_version == AR5K_AR5210) {
+			timer1 = 0xffffffff;
+			timer2 = 0xffffffff;
+		} else {
+			timer1 = 0x0000ffff;
+			timer2 = 0x0007ffff;
+		}
+		/* Mark associated AP as PCF incapable for now */
+		AR5K_REG_DISABLE_BITS(ah, AR5K_STA_ID1, AR5K_STA_ID1_PCF);
+		break;
+	case NL80211_IFTYPE_ADHOC:
+		AR5K_REG_ENABLE_BITS(ah, AR5K_TXCFG, AR5K_TXCFG_ADHOC_BCN_ATIM);
+		/* fall through */
+	default:
+		/* On non-STA modes timer1 is used as next DMA
+		 * beacon alert (DBA) timer and timer2 as next
+		 * software beacon alert. Both in 1/8TUs. */
+		timer1 = (next_beacon - AR5K_TUNE_DMA_BEACON_RESP) << 3;
+		timer2 = (next_beacon - AR5K_TUNE_SW_BEACON_RESP) << 3;
+		break;
+	}
+
+	/* Timer3 marks the end of our ATIM window
+	 * a zero length window is not allowed because
+	 * we 'll get no beacons */
+	timer3 = next_beacon + 1;
+
+	/*
+	 * Set the beacon register and enable all timers.
+	 */
+	/* When in AP or Mesh Point mode zero timer0 to start TSF */
+	if (ah->opmode == NL80211_IFTYPE_AP ||
+	    ah->opmode == NL80211_IFTYPE_MESH_POINT)
+		ath5k_hw_reg_write(ah, 0, AR5K_TIMER0);
+
+	ath5k_hw_reg_write(ah, next_beacon, AR5K_TIMER0);
+	ath5k_hw_reg_write(ah, timer1, AR5K_TIMER1);
+	ath5k_hw_reg_write(ah, timer2, AR5K_TIMER2);
+	ath5k_hw_reg_write(ah, timer3, AR5K_TIMER3);
+
+	/* Force a TSF reset if requested and enable beacons */
+	if (interval & AR5K_BEACON_RESET_TSF)
+		ath5k_hw_reset_tsf(ah);
+
+	ath5k_hw_reg_write(ah, interval & (AR5K_BEACON_PERIOD |
+					AR5K_BEACON_ENABLE),
+						AR5K_BEACON);
+
+	/* Flush any pending BMISS interrupts on ISR by
+	 * performing a clear-on-write operation on PISR
+	 * register for the BMISS bit (writing a bit on
+	 * ISR toggles a reset for that bit and leaves
+	 * the remaining bits intact) */
+	if (ah->ah_version == AR5K_AR5210)
+		ath5k_hw_reg_write(ah, AR5K_ISR_BMISS, AR5K_ISR);
+	else
+		ath5k_hw_reg_write(ah, AR5K_ISR_BMISS, AR5K_PISR);
+
+	/* TODO: Set enhanced sleep registers on AR5212
+	 * based on vif->bss_conf params, until then
+	 * disable power save reporting.*/
+	AR5K_REG_DISABLE_BITS(ah, AR5K_STA_ID1, AR5K_STA_ID1_PWR_SV);
+
+}
+
+/**
+ * ath5k_check_timer_win() - Check if timer B is timer A + window
+ * @a: timer a (before b)
+ * @b: timer b (after a)
+ * @window: difference between a and b
+ * @intval: timers are increased by this interval
+ *
+ * This helper function checks if timer B is timer A + window and covers
+ * cases where timer A or B might have already been updated or wrapped
+ * around (Timers are 16 bit).
+ *
+ * Returns true if O.K.
+ */
+static inline bool
+ath5k_check_timer_win(int a, int b, int window, int intval)
+{
+	/*
+	 * 1.) usually B should be A + window
+	 * 2.) A already updated, B not updated yet
+	 * 3.) A already updated and has wrapped around
+	 * 4.) B has wrapped around
+	 */
+	if ((b - a == window) ||				/* 1.) */
+	    (a - b == intval - window) ||			/* 2.) */
+	    ((a | 0x10000) - b == intval - window) ||		/* 3.) */
+	    ((b | 0x10000) - a == window))			/* 4.) */
+		return true; /* O.K. */
+	return false;
+}
+
+/**
+ * ath5k_hw_check_beacon_timers() - Check if the beacon timers are correct
+ * @ah: The &struct ath5k_hw
+ * @intval: beacon interval
+ *
+ * This is a workaround for IBSS mode
+ *
+ * The need for this function arises from the fact that we have 4 separate
+ * HW timer registers (TIMER0 - TIMER3), which are closely related to the
+ * next beacon target time (NBTT), and that the HW updates these timers
+ * separately based on the current TSF value. The hardware increments each
+ * timer by the beacon interval, when the local TSF converted to TU is equal
+ * to the value stored in the timer.
+ *
+ * The reception of a beacon with the same BSSID can update the local HW TSF
+ * at any time - this is something we can't avoid. If the TSF jumps to a
+ * time which is later than the time stored in a timer, this timer will not
+ * be updated until the TSF in TU wraps around at 16 bit (the size of the
+ * timers) and reaches the time which is stored in the timer.
+ *
+ * The problem is that these timers are closely related to TIMER0 (NBTT) and
+ * that they define a time "window". When the TSF jumps between two timers
+ * (e.g. ATIM and NBTT), the one in the past will be left behind (not
+ * updated), while the one in the future will be updated every beacon
+ * interval. This causes the window to get larger, until the TSF wraps
+ * around as described above and the timer which was left behind gets
+ * updated again. But - because the beacon interval is usually not an exact
+ * divisor of the size of the timers (16 bit), an unwanted "window" between
+ * these timers has developed!
+ *
+ * This is especially important with the ATIM window, because during
+ * the ATIM window only ATIM frames and no data frames are allowed to be
+ * sent, which creates transmission pauses after each beacon. This symptom
+ * has been described as "ramping ping" because ping times increase linearly
+ * for some time and then drop down again. A wrong window on the DMA beacon
+ * timer has the same effect, so we check for these two conditions.
+ *
+ * Returns true if O.K.
+ */
+bool
+ath5k_hw_check_beacon_timers(struct ath5k_hw *ah, int intval)
+{
+	unsigned int nbtt, atim, dma;
+
+	nbtt = ath5k_hw_reg_read(ah, AR5K_TIMER0);
+	atim = ath5k_hw_reg_read(ah, AR5K_TIMER3);
+	dma = ath5k_hw_reg_read(ah, AR5K_TIMER1) >> 3;
+
+	/* NOTE: SWBA is different. Having a wrong window there does not
+	 * stop us from sending data and this condition is caught by
+	 * other means (SWBA interrupt) */
+
+	if (ath5k_check_timer_win(nbtt, atim, 1, intval) &&
+	    ath5k_check_timer_win(dma, nbtt, AR5K_TUNE_DMA_BEACON_RESP,
+				  intval))
+		return true; /* O.K. */
+	return false;
+}
+
+/**
+ * ath5k_hw_set_coverage_class() - Set IEEE 802.11 coverage class
+ * @ah: The &struct ath5k_hw
+ * @coverage_class: IEEE 802.11 coverage class number
+ *
+ * Sets IFS intervals and ACK/CTS timeouts for given coverage class.
+ */
+void
+ath5k_hw_set_coverage_class(struct ath5k_hw *ah, u8 coverage_class)
+{
+	/* As defined by IEEE 802.11-2007 17.3.8.6 */
+	int slot_time = ath5k_hw_get_default_slottime(ah) + 3 * coverage_class;
+	int ack_timeout = ath5k_hw_get_default_sifs(ah) + slot_time;
+	int cts_timeout = ack_timeout;
+
+	ath5k_hw_set_ifs_intervals(ah, slot_time);
+	ath5k_hw_set_ack_timeout(ah, ack_timeout);
+	ath5k_hw_set_cts_timeout(ah, cts_timeout);
+
+	ah->ah_coverage_class = coverage_class;
+}
+
+/***************************\
+* Init/Start/Stop functions *
+\***************************/
+
+/**
+ * ath5k_hw_start_rx_pcu() - Start RX engine
+ * @ah: The &struct ath5k_hw
+ *
+ * Starts RX engine on PCU so that hw can process RXed frames
+ * (ACK etc).
+ *
+ * NOTE: RX DMA should be already enabled using ath5k_hw_start_rx_dma
+ */
+void
+ath5k_hw_start_rx_pcu(struct ath5k_hw *ah)
+{
+	AR5K_REG_DISABLE_BITS(ah, AR5K_DIAG_SW, AR5K_DIAG_SW_DIS_RX);
+}
+
+/**
+ * at5k_hw_stop_rx_pcu() - Stop RX engine
+ * @ah: The &struct ath5k_hw
+ *
+ * Stops RX engine on PCU
+ */
+void
+ath5k_hw_stop_rx_pcu(struct ath5k_hw *ah)
+{
+	AR5K_REG_ENABLE_BITS(ah, AR5K_DIAG_SW, AR5K_DIAG_SW_DIS_RX);
+}
+
+/**
+ * ath5k_hw_set_opmode() - Set PCU operating mode
+ * @ah: The &struct ath5k_hw
+ * @op_mode: One of enum nl80211_iftype
+ *
+ * Configure PCU for the various operating modes (AP/STA etc)
+ */
+int
+ath5k_hw_set_opmode(struct ath5k_hw *ah, enum nl80211_iftype op_mode)
+{
+	struct ath_common *common = ath5k_hw_common(ah);
+	u32 pcu_reg, beacon_reg, low_id, high_id;
+
+	ATH5K_DBG(ah, ATH5K_DEBUG_MODE, "mode %d\n", op_mode);
+
+	/* Preserve rest settings */
+	pcu_reg = ath5k_hw_reg_read(ah, AR5K_STA_ID1) & 0xffff0000;
+	pcu_reg &= ~(AR5K_STA_ID1_ADHOC | AR5K_STA_ID1_AP
+			| AR5K_STA_ID1_KEYSRCH_MODE
+			| (ah->ah_version == AR5K_AR5210 ?
+			(AR5K_STA_ID1_PWR_SV | AR5K_STA_ID1_NO_PSPOLL) : 0));
+
+	beacon_reg = 0;
+
+	switch (op_mode) {
+	case NL80211_IFTYPE_ADHOC:
+		pcu_reg |= AR5K_STA_ID1_ADHOC | AR5K_STA_ID1_KEYSRCH_MODE;
+		beacon_reg |= AR5K_BCR_ADHOC;
+		if (ah->ah_version == AR5K_AR5210)
+			pcu_reg |= AR5K_STA_ID1_NO_PSPOLL;
+		else
+			AR5K_REG_ENABLE_BITS(ah, AR5K_CFG, AR5K_CFG_IBSS);
+		break;
+
+	case NL80211_IFTYPE_AP:
+	case NL80211_IFTYPE_MESH_POINT:
+		pcu_reg |= AR5K_STA_ID1_AP | AR5K_STA_ID1_KEYSRCH_MODE;
+		beacon_reg |= AR5K_BCR_AP;
+		if (ah->ah_version == AR5K_AR5210)
+			pcu_reg |= AR5K_STA_ID1_NO_PSPOLL;
+		else
+			AR5K_REG_DISABLE_BITS(ah, AR5K_CFG, AR5K_CFG_IBSS);
+		break;
+
+	case NL80211_IFTYPE_STATION:
+		pcu_reg |= AR5K_STA_ID1_KEYSRCH_MODE
+			| (ah->ah_version == AR5K_AR5210 ?
+				AR5K_STA_ID1_PWR_SV : 0);
+		/* fall through */
+	case NL80211_IFTYPE_MONITOR:
+		pcu_reg |= AR5K_STA_ID1_KEYSRCH_MODE
+			| (ah->ah_version == AR5K_AR5210 ?
+				AR5K_STA_ID1_NO_PSPOLL : 0);
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	/*
+	 * Set PCU registers
+	 */
+	low_id = get_unaligned_le32(common->macaddr);
+	high_id = get_unaligned_le16(common->macaddr + 4);
+	ath5k_hw_reg_write(ah, low_id, AR5K_STA_ID0);
+	ath5k_hw_reg_write(ah, pcu_reg | high_id, AR5K_STA_ID1);
+
+	/*
+	 * Set Beacon Control Register on 5210
+	 */
+	if (ah->ah_version == AR5K_AR5210)
+		ath5k_hw_reg_write(ah, beacon_reg, AR5K_BCR);
+
+	return 0;
+}
+
+/**
+ * ath5k_hw_pcu_init() - Initialize PCU
+ * @ah: The &struct ath5k_hw
+ * @op_mode: One of enum nl80211_iftype
+ * @mode: One of enum ath5k_driver_mode
+ *
+ * This function is used to initialize PCU by setting current
+ * operation mode and various other settings.
+ */
+void
+ath5k_hw_pcu_init(struct ath5k_hw *ah, enum nl80211_iftype op_mode)
+{
+	/* Set bssid and bssid mask */
+	ath5k_hw_set_bssid(ah);
+
+	/* Set PCU config */
+	ath5k_hw_set_opmode(ah, op_mode);
+
+	/* Write rate duration table only on AR5212 and if
+	 * virtual interface has already been brought up
+	 * XXX: rethink this after new mode changes to
+	 * mac80211 are integrated */
+	if (ah->ah_version == AR5K_AR5212 &&
+		ah->nvifs)
+		ath5k_hw_write_rate_duration(ah);
+
+	/* Set RSSI/BRSSI thresholds
+	 *
+	 * Note: If we decide to set this value
+	 * dynamically, have in mind that when AR5K_RSSI_THR
+	 * register is read it might return 0x40 if we haven't
+	 * wrote anything to it plus BMISS RSSI threshold is zeroed.
+	 * So doing a save/restore procedure here isn't the right
+	 * choice. Instead store it on ath5k_hw */
+	ath5k_hw_reg_write(ah, (AR5K_TUNE_RSSI_THRES |
+				AR5K_TUNE_BMISS_THRES <<
+				AR5K_RSSI_THR_BMISS_S),
+				AR5K_RSSI_THR);
+
+	/* MIC QoS support */
+	if (ah->ah_mac_srev >= AR5K_SREV_AR2413) {
+		ath5k_hw_reg_write(ah, 0x000100aa, AR5K_MIC_QOS_CTL);
+		ath5k_hw_reg_write(ah, 0x00003210, AR5K_MIC_QOS_SEL);
+	}
+
+	/* QoS NOACK Policy */
+	if (ah->ah_version == AR5K_AR5212) {
+		ath5k_hw_reg_write(ah,
+			AR5K_REG_SM(2, AR5K_QOS_NOACK_2BIT_VALUES) |
+			AR5K_REG_SM(5, AR5K_QOS_NOACK_BIT_OFFSET)  |
+			AR5K_REG_SM(0, AR5K_QOS_NOACK_BYTE_OFFSET),
+			AR5K_QOS_NOACK);
+	}
+
+	/* Restore slot time and ACK timeouts */
+	if (ah->ah_coverage_class > 0)
+		ath5k_hw_set_coverage_class(ah, ah->ah_coverage_class);
+
+	/* Set ACK bitrate mode (see ack_rates_high) */
+	if (ah->ah_version == AR5K_AR5212) {
+		u32 val = AR5K_STA_ID1_BASE_RATE_11B | AR5K_STA_ID1_ACKCTS_6MB;
+		if (ah->ah_ack_bitrate_high)
+			AR5K_REG_DISABLE_BITS(ah, AR5K_STA_ID1, val);
+		else
+			AR5K_REG_ENABLE_BITS(ah, AR5K_STA_ID1, val);
+	}
+	return;
+}