drivers/net/wireless/ath/ath9k/wow.c

/*
 * Copyright (c) 2012 Qualcomm Atheros, Inc.
 *
 * Permission to use, copy, modify, and/or 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.
 */

#include <linux/export.h>
#include "ath9k.h"
#include "reg.h"
#include "hw-ops.h"

const char *ath9k_hw_wow_event_to_string(u32 wow_event)
{
	if (wow_event & AH_WOW_MAGIC_PATTERN_EN)
		return "Magic pattern";
	if (wow_event & AH_WOW_USER_PATTERN_EN)
		return "User pattern";
	if (wow_event & AH_WOW_LINK_CHANGE)
		return "Link change";
	if (wow_event & AH_WOW_BEACON_MISS)
		return "Beacon miss";

	return  "unknown reason";
}
EXPORT_SYMBOL(ath9k_hw_wow_event_to_string);

static void ath9k_hw_set_powermode_wow_sleep(struct ath_hw *ah)
{
	struct ath_common *common = ath9k_hw_common(ah);

	REG_SET_BIT(ah, AR_STA_ID1, AR_STA_ID1_PWR_SAV);

	/* set rx disable bit */
	REG_WRITE(ah, AR_CR, AR_CR_RXD);

	if (!ath9k_hw_wait(ah, AR_CR, AR_CR_RXE, 0, AH_WAIT_TIMEOUT)) {
		ath_err(common, "Failed to stop Rx DMA in 10ms AR_CR=0x%08x AR_DIAG_SW=0x%08x\n",
			REG_READ(ah, AR_CR), REG_READ(ah, AR_DIAG_SW));
		return;
	}

	REG_WRITE(ah, AR_RTC_FORCE_WAKE, AR_RTC_FORCE_WAKE_ON_INT);
}

static void ath9k_wow_create_keep_alive_pattern(struct ath_hw *ah)
{
	struct ath_common *common = ath9k_hw_common(ah);
	u8 sta_mac_addr[ETH_ALEN], ap_mac_addr[ETH_ALEN];
	u32 ctl[13] = {0};
	u32 data_word[KAL_NUM_DATA_WORDS];
	u8 i;
	u32 wow_ka_data_word0;

	memcpy(sta_mac_addr, common->macaddr, ETH_ALEN);
	memcpy(ap_mac_addr, common->curbssid, ETH_ALEN);

	/* set the transmit buffer */
	ctl[0] = (KAL_FRAME_LEN | (MAX_RATE_POWER << 16));
	ctl[1] = 0;
	ctl[3] = 0xb;	/* OFDM_6M hardware value for this rate */
	ctl[4] = 0;
	ctl[7] = (ah->txchainmask) << 2;
	ctl[2] = 0xf << 16; /* tx_tries 0 */

	for (i = 0; i < KAL_NUM_DESC_WORDS; i++)
		REG_WRITE(ah, (AR_WOW_KA_DESC_WORD2 + i * 4), ctl[i]);

	REG_WRITE(ah, (AR_WOW_KA_DESC_WORD2 + i * 4), ctl[i]);

	data_word[0] = (KAL_FRAME_TYPE << 2) | (KAL_FRAME_SUB_TYPE << 4) |
		       (KAL_TO_DS << 8) | (KAL_DURATION_ID << 16);
	data_word[1] = (ap_mac_addr[3] << 24) | (ap_mac_addr[2] << 16) |
		       (ap_mac_addr[1] << 8) | (ap_mac_addr[0]);
	data_word[2] = (sta_mac_addr[1] << 24) | (sta_mac_addr[0] << 16) |
		       (ap_mac_addr[5] << 8) | (ap_mac_addr[4]);
	data_word[3] = (sta_mac_addr[5] << 24) | (sta_mac_addr[4] << 16) |
		       (sta_mac_addr[3] << 8) | (sta_mac_addr[2]);
	data_word[4] = (ap_mac_addr[3] << 24) | (ap_mac_addr[2] << 16) |
		       (ap_mac_addr[1] << 8) | (ap_mac_addr[0]);
	data_word[5] = (ap_mac_addr[5] << 8) | (ap_mac_addr[4]);

	if (AR_SREV_9462_20(ah)) {
		/* AR9462 2.0 has an extra descriptor word (time based
		 * discard) compared to other chips */
		REG_WRITE(ah, (AR_WOW_KA_DESC_WORD2 + (12 * 4)), 0);
		wow_ka_data_word0 = AR_WOW_TXBUF(13);
	} else {
		wow_ka_data_word0 = AR_WOW_TXBUF(12);
	}

	for (i = 0; i < KAL_NUM_DATA_WORDS; i++)
		REG_WRITE(ah, (wow_ka_data_word0 + i*4), data_word[i]);

}

void ath9k_hw_wow_apply_pattern(struct ath_hw *ah, u8 *user_pattern,
				u8 *user_mask, int pattern_count,
				int pattern_len)
{
	int i;
	u32 pattern_val, mask_val;
	u32 set, clr;

	/* FIXME: should check count by querying the hardware capability */
	if (pattern_count >= MAX_NUM_PATTERN)
		return;

	REG_SET_BIT(ah, AR_WOW_PATTERN, BIT(pattern_count));

	/* set the registers for pattern */
	for (i = 0; i < MAX_PATTERN_SIZE; i += 4) {
		memcpy(&pattern_val, user_pattern, 4);
		REG_WRITE(ah, (AR_WOW_TB_PATTERN(pattern_count) + i),
			  pattern_val);
		user_pattern += 4;
	}

	/* set the registers for mask */
	for (i = 0; i < MAX_PATTERN_MASK_SIZE; i += 4) {
		memcpy(&mask_val, user_mask, 4);
		REG_WRITE(ah, (AR_WOW_TB_MASK(pattern_count) + i), mask_val);
		user_mask += 4;
	}

	/* set the pattern length to be matched
	 *
	 * AR_WOW_LENGTH1_REG1
	 * bit 31:24 pattern 0 length
	 * bit 23:16 pattern 1 length
	 * bit 15:8 pattern 2 length
	 * bit 7:0 pattern 3 length
	 *
	 * AR_WOW_LENGTH1_REG2
	 * bit 31:24 pattern 4 length
	 * bit 23:16 pattern 5 length
	 * bit 15:8 pattern 6 length
	 * bit 7:0 pattern 7 length
	 *
	 * the below logic writes out the new
	 * pattern length for the corresponding
	 * pattern_count, while masking out the
	 * other fields
	 */

	ah->wow_event_mask |= BIT(pattern_count + AR_WOW_PAT_FOUND_SHIFT);

	if (pattern_count < 4) {
		/* Pattern 0-3 uses AR_WOW_LENGTH1 register */
		set = (pattern_len & AR_WOW_LENGTH_MAX) <<
		       AR_WOW_LEN1_SHIFT(pattern_count);
		clr = AR_WOW_LENGTH1_MASK(pattern_count);
		REG_RMW(ah, AR_WOW_LENGTH1, set, clr);
	} else {
		/* Pattern 4-7 uses AR_WOW_LENGTH2 register */
		set = (pattern_len & AR_WOW_LENGTH_MAX) <<
		       AR_WOW_LEN2_SHIFT(pattern_count);
		clr = AR_WOW_LENGTH2_MASK(pattern_count);
		REG_RMW(ah, AR_WOW_LENGTH2, set, clr);
	}

}
EXPORT_SYMBOL(ath9k_hw_wow_apply_pattern);

u32 ath9k_hw_wow_wakeup(struct ath_hw *ah)
{
	u32 wow_status = 0;
	u32 val = 0, rval;

	/*
	 * read the WoW status register to know
	 * the wakeup reason
	 */
	rval = REG_READ(ah, AR_WOW_PATTERN);
	val = AR_WOW_STATUS(rval);

	/*
	 * mask only the WoW events that we have enabled. Sometimes
	 * we have spurious WoW events from the AR_WOW_PATTERN
	 * register. This mask will clean it up.
	 */

	val &= ah->wow_event_mask;

	if (val) {
		if (val & AR_WOW_MAGIC_PAT_FOUND)
			wow_status |= AH_WOW_MAGIC_PATTERN_EN;
		if (AR_WOW_PATTERN_FOUND(val))
			wow_status |= AH_WOW_USER_PATTERN_EN;
		if (val & AR_WOW_KEEP_ALIVE_FAIL)
			wow_status |= AH_WOW_LINK_CHANGE;
		if (val & AR_WOW_BEACON_FAIL)
			wow_status |= AH_WOW_BEACON_MISS;
	}

	/*
	 * set and clear WOW_PME_CLEAR registers for the chip to
	 * generate next wow signal.
	 * disable D3 before accessing other registers ?
	 */

	/* do we need to check the bit value 0x01000000 (7-10) ?? */
	REG_RMW(ah, AR_PCIE_PM_CTRL, AR_PMCTRL_WOW_PME_CLR,
		AR_PMCTRL_PWR_STATE_D1D3);

	/*
	 * clear all events
	 */
	REG_WRITE(ah, AR_WOW_PATTERN,
		  AR_WOW_CLEAR_EVENTS(REG_READ(ah, AR_WOW_PATTERN)));

	/*
	 * restore the beacon threshold to init value
	 */
	REG_WRITE(ah, AR_RSSI_THR, INIT_RSSI_THR);

	/*
	 * Restore the way the PCI-E reset, Power-On-Reset, external
	 * PCIE_POR_SHORT pins are tied to its original value.
	 * Previously just before WoW sleep, we untie the PCI-E
	 * reset to our Chip's Power On Reset so that any PCI-E
	 * reset from the bus will not reset our chip
	 */
	if (ah->is_pciexpress)
		ath9k_hw_configpcipowersave(ah, false);

	ah->wow_event_mask = 0;

	return wow_status;
}
EXPORT_SYMBOL(ath9k_hw_wow_wakeup);

void ath9k_hw_wow_enable(struct ath_hw *ah, u32 pattern_enable)
{
	u32 wow_event_mask;
	u32 set, clr;

	/*
	 * wow_event_mask is a mask to the AR_WOW_PATTERN register to
	 * indicate which WoW events we have enabled. The WoW events
	 * are from the 'pattern_enable' in this function and
	 * 'pattern_count' of ath9k_hw_wow_apply_pattern()
	 */
	wow_event_mask = ah->wow_event_mask;

	/*
	 * Untie Power-on-Reset from the PCI-E-Reset. When we are in
	 * WOW sleep, we do want the Reset from the PCI-E to disturb
	 * our hw state
	 */
	if (ah->is_pciexpress) {
		/*
		 * we need to untie the internal POR (power-on-reset)
		 * to the external PCI-E reset. We also need to tie
		 * the PCI-E Phy reset to the PCI-E reset.
		 */
		set = AR_WA_RESET_EN | AR_WA_POR_SHORT;
		clr = AR_WA_UNTIE_RESET_EN | AR_WA_D3_L1_DISABLE;
		REG_RMW(ah, AR_WA, set, clr);
	}

	/*
	 * set the power states appropriately and enable PME
	 */
	set = AR_PMCTRL_HOST_PME_EN | AR_PMCTRL_PWR_PM_CTRL_ENA |
	      AR_PMCTRL_AUX_PWR_DET | AR_PMCTRL_WOW_PME_CLR;

	/*
	 * set and clear WOW_PME_CLEAR registers for the chip
	 * to generate next wow signal.
	 */
	REG_SET_BIT(ah, AR_PCIE_PM_CTRL, set);
	clr = AR_PMCTRL_WOW_PME_CLR;
	REG_CLR_BIT(ah, AR_PCIE_PM_CTRL, clr);

	/*
	 * Setup for:
	 *	- beacon misses
	 *	- magic pattern
	 *	- keep alive timeout
	 *	- pattern matching
	 */

	/*
	 * Program default values for pattern backoff, aifs/slot/KAL count,
	 * beacon miss timeout, KAL timeout, etc.
	 */
	set = AR_WOW_BACK_OFF_SHIFT(AR_WOW_PAT_BACKOFF);
	REG_SET_BIT(ah, AR_WOW_PATTERN, set);

	set = AR_WOW_AIFS_CNT(AR_WOW_CNT_AIFS_CNT) |
	      AR_WOW_SLOT_CNT(AR_WOW_CNT_SLOT_CNT) |
	      AR_WOW_KEEP_ALIVE_CNT(AR_WOW_CNT_KA_CNT);
	REG_SET_BIT(ah, AR_WOW_COUNT, set);

	if (pattern_enable & AH_WOW_BEACON_MISS)
		set = AR_WOW_BEACON_TIMO;
	/* We are not using beacon miss, program a large value */
	else
		set = AR_WOW_BEACON_TIMO_MAX;

	REG_WRITE(ah, AR_WOW_BCN_TIMO, set);

	/*
	 * Keep alive timo in ms except AR9280
	 */
	if (!pattern_enable)
		set = AR_WOW_KEEP_ALIVE_NEVER;
	else
		set = KAL_TIMEOUT * 32;

	REG_WRITE(ah, AR_WOW_KEEP_ALIVE_TIMO, set);

	/*
	 * Keep alive delay in us. based on 'power on clock',
	 * therefore in usec
	 */
	set = KAL_DELAY * 1000;
	REG_WRITE(ah, AR_WOW_KEEP_ALIVE_DELAY, set);

	/*
	 * Create keep alive pattern to respond to beacons
	 */
	ath9k_wow_create_keep_alive_pattern(ah);

	/*
	 * Configure MAC WoW Registers
	 */
	set = 0;
	/* Send keep alive timeouts anyway */
	clr = AR_WOW_KEEP_ALIVE_AUTO_DIS;

	if (pattern_enable & AH_WOW_LINK_CHANGE)
		wow_event_mask |= AR_WOW_KEEP_ALIVE_FAIL;
	else
		set = AR_WOW_KEEP_ALIVE_FAIL_DIS;

	set = AR_WOW_KEEP_ALIVE_FAIL_DIS;
	REG_RMW(ah, AR_WOW_KEEP_ALIVE, set, clr);

	/*
	 * we are relying on a bmiss failure. ensure we have
	 * enough threshold to prevent false positives
	 */
	REG_RMW_FIELD(ah, AR_RSSI_THR, AR_RSSI_THR_BM_THR,
		      AR_WOW_BMISSTHRESHOLD);

	set = 0;
	clr = 0;

	if (pattern_enable & AH_WOW_BEACON_MISS) {
		set = AR_WOW_BEACON_FAIL_EN;
		wow_event_mask |= AR_WOW_BEACON_FAIL;
	} else {
		clr = AR_WOW_BEACON_FAIL_EN;
	}

	REG_RMW(ah, AR_WOW_BCN_EN, set, clr);

	set = 0;
	clr = 0;
	/*
	 * Enable the magic packet registers
	 */
	if (pattern_enable & AH_WOW_MAGIC_PATTERN_EN) {
		set = AR_WOW_MAGIC_EN;
		wow_event_mask |= AR_WOW_MAGIC_PAT_FOUND;
	} else {
		clr = AR_WOW_MAGIC_EN;
	}
	set |= AR_WOW_MAC_INTR_EN;
	REG_RMW(ah, AR_WOW_PATTERN, set, clr);

	REG_WRITE(ah, AR_WOW_PATTERN_MATCH_LT_256B,
		  AR_WOW_PATTERN_SUPPORTED);

	/*
	 * Set the power states appropriately and enable PME
	 */
	clr = 0;
	set = AR_PMCTRL_PWR_STATE_D1D3 | AR_PMCTRL_HOST_PME_EN |
	      AR_PMCTRL_PWR_PM_CTRL_ENA;

	clr = AR_PCIE_PM_CTRL_ENA;
	REG_RMW(ah, AR_PCIE_PM_CTRL, set, clr);

	/*
	 * this is needed to prevent the chip waking up
	 * the host within 3-4 seconds with certain
	 * platform/BIOS. The fix is to enable
	 * D1 & D3 to match original definition and
	 * also match the OTP value. Anyway this
	 * is more related to SW WOW.
	 */
	clr = AR_PMCTRL_PWR_STATE_D1D3;
	REG_CLR_BIT(ah, AR_PCIE_PM_CTRL, clr);

	set = AR_PMCTRL_PWR_STATE_D1D3_REAL;
	REG_SET_BIT(ah, AR_PCIE_PM_CTRL, set);

	REG_CLR_BIT(ah, AR_STA_ID1, AR_STA_ID1_PRESERVE_SEQNUM);

	/* to bring down WOW power low margin */
	set = BIT(13);
	REG_SET_BIT(ah, AR_PCIE_PHY_REG3, set);
	/* HW WoW */
	clr = BIT(5);
	REG_CLR_BIT(ah, AR_PCU_MISC_MODE3, clr);

	ath9k_hw_set_powermode_wow_sleep(ah);
	ah->wow_event_mask = wow_event_mask;
}
EXPORT_SYMBOL(ath9k_hw_wow_enable);