diff options
Diffstat (limited to 'drivers/net/wireless/ath/ath5k/pcu.c')
| -rw-r--r-- | drivers/net/wireless/ath/ath5k/pcu.c | 284 |
1 files changed, 93 insertions, 191 deletions
diff --git a/drivers/net/wireless/ath/ath5k/pcu.c b/drivers/net/wireless/ath/ath5k/pcu.c index 86fdb6ddfaaa..095d30b50ec7 100644 --- a/drivers/net/wireless/ath/ath5k/pcu.c +++ b/drivers/net/wireless/ath/ath5k/pcu.c @@ -137,11 +137,11 @@ void ath5k_hw_update_mib_counters(struct ath5k_hw *ah) * ath5k_hw_set_ack_bitrate - set bitrate for ACKs * * @ah: The &struct ath5k_hw - * @high: Flag to determine if we want to use high transmition rate + * @high: Flag to determine if we want to use high transmission rate * for ACKs or not * * If high flag is set, we tell hw to use a set of control rates based on - * the current transmition rate (check out control_rates array inside reset.c). + * the current transmission rate (check out control_rates array inside reset.c). * If not hw just uses the lowest rate available for the current modulation * scheme being used (1Mbit for CCK and 6Mbits for OFDM). */ @@ -308,27 +308,26 @@ int ath5k_hw_set_lladdr(struct ath5k_hw *ah, const u8 *mac) } /** - * ath5k_hw_set_associd - Set BSSID for association + * ath5k_hw_set_bssid - Set current BSSID on hw * * @ah: The &struct ath5k_hw - * @bssid: BSSID - * @assoc_id: Assoc id * - * Sets the BSSID which trigers the "SME Join" operation + * Sets the current BSSID and BSSID mask we have from the + * common struct into the hardware */ -void ath5k_hw_set_associd(struct ath5k_hw *ah) +void ath5k_hw_set_bssid(struct ath5k_hw *ah) { struct ath_common *common = ath5k_hw_common(ah); u16 tim_offset = 0; /* - * Set simple BSSID mask on 5212 + * Set BSSID mask on 5212 */ if (ah->ah_version == AR5K_AR5212) ath_hw_setbssidmask(common); /* - * Set BSSID which triggers the "SME Join" operation + * Set BSSID */ ath5k_hw_reg_write(ah, get_unaligned_le32(common->curbssid), @@ -496,6 +495,10 @@ 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 @@ -518,6 +521,8 @@ u64 ath5k_hw_get_tsf64(struct ath5k_hw *ah) tsf_upper1 = tsf_upper2; } + local_irq_restore(flags); + WARN_ON( i == ATH5K_MAX_TSF_READ ); return (((u64)tsf_upper1 << 32) | tsf_lower); @@ -601,7 +606,7 @@ void ath5k_hw_init_beacon(struct ath5k_hw *ah, u32 next_beacon, u32 interval) /* Timer3 marks the end of our ATIM window * a zero length window is not allowed because * we 'll get no beacons */ - timer3 = next_beacon + (ah->ah_atim_window ? ah->ah_atim_window : 1); + timer3 = next_beacon + 1; /* * Set the beacon register and enable all timers. @@ -641,198 +646,95 @@ void ath5k_hw_init_beacon(struct ath5k_hw *ah, u32 next_beacon, u32 interval) } - -/*********************\ -* Key table functions * -\*********************/ - -/* - * Reset a key entry on the table +/** + * 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. */ -int ath5k_hw_reset_key(struct ath5k_hw *ah, u16 entry) +static inline bool +ath5k_check_timer_win(int a, int b, int window, int intval) { - unsigned int i, type; - u16 micentry = entry + AR5K_KEYTABLE_MIC_OFFSET; - - AR5K_ASSERT_ENTRY(entry, AR5K_KEYTABLE_SIZE); - - type = ath5k_hw_reg_read(ah, AR5K_KEYTABLE_TYPE(entry)); - - for (i = 0; i < AR5K_KEYCACHE_SIZE; i++) - ath5k_hw_reg_write(ah, 0, AR5K_KEYTABLE_OFF(entry, i)); - - /* Reset associated MIC entry if TKIP - * is enabled located at offset (entry + 64) */ - if (type == AR5K_KEYTABLE_TYPE_TKIP) { - AR5K_ASSERT_ENTRY(micentry, AR5K_KEYTABLE_SIZE); - for (i = 0; i < AR5K_KEYCACHE_SIZE / 2 ; i++) - ath5k_hw_reg_write(ah, 0, - AR5K_KEYTABLE_OFF(micentry, i)); - } - /* - * Set NULL encryption on AR5212+ - * - * Note: AR5K_KEYTABLE_TYPE -> AR5K_KEYTABLE_OFF(entry, 5) - * AR5K_KEYTABLE_TYPE_NULL -> 0x00000007 - * - * Note2: Windows driver (ndiswrapper) sets this to - * 0x00000714 instead of 0x00000007 + * 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 (ah->ah_version >= AR5K_AR5211) { - ath5k_hw_reg_write(ah, AR5K_KEYTABLE_TYPE_NULL, - AR5K_KEYTABLE_TYPE(entry)); - - if (type == AR5K_KEYTABLE_TYPE_TKIP) { - ath5k_hw_reg_write(ah, AR5K_KEYTABLE_TYPE_NULL, - AR5K_KEYTABLE_TYPE(micentry)); - } - } - - return 0; + 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; } -static -int ath5k_keycache_type(const struct ieee80211_key_conf *key) -{ - switch (key->alg) { - case ALG_TKIP: - return AR5K_KEYTABLE_TYPE_TKIP; - case ALG_CCMP: - return AR5K_KEYTABLE_TYPE_CCM; - case ALG_WEP: - if (key->keylen == WLAN_KEY_LEN_WEP40) - return AR5K_KEYTABLE_TYPE_40; - else if (key->keylen == WLAN_KEY_LEN_WEP104) - return AR5K_KEYTABLE_TYPE_104; - return -EINVAL; - default: - return -EINVAL; - } - return -EINVAL; -} - -/* - * Set a key entry on the table +/** + * 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 + * seperately based on the current TSF value. The hardware increments each + * timer by the beacon interval, when the local TSF coverted 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. */ -int ath5k_hw_set_key(struct ath5k_hw *ah, u16 entry, - const struct ieee80211_key_conf *key, const u8 *mac) +bool +ath5k_hw_check_beacon_timers(struct ath5k_hw *ah, int intval) { - unsigned int i; - int keylen; - __le32 key_v[5] = {}; - __le32 key0 = 0, key1 = 0; - __le32 *rxmic, *txmic; - int keytype; - u16 micentry = entry + AR5K_KEYTABLE_MIC_OFFSET; - bool is_tkip; - const u8 *key_ptr; - - is_tkip = (key->alg == ALG_TKIP); - - /* - * key->keylen comes in from mac80211 in bytes. - * TKIP is 128 bit + 128 bit mic - */ - keylen = (is_tkip) ? (128 / 8) : key->keylen; - - if (entry > AR5K_KEYTABLE_SIZE || - (is_tkip && micentry > AR5K_KEYTABLE_SIZE)) - return -EOPNOTSUPP; - - if (unlikely(keylen > 16)) - return -EOPNOTSUPP; - - keytype = ath5k_keycache_type(key); - if (keytype < 0) - return keytype; + unsigned int nbtt, atim, dma; - /* - * each key block is 6 bytes wide, written as pairs of - * alternating 32 and 16 bit le values. - */ - key_ptr = key->key; - for (i = 0; keylen >= 6; keylen -= 6) { - memcpy(&key_v[i], key_ptr, 6); - i += 2; - key_ptr += 6; - } - if (keylen) - memcpy(&key_v[i], key_ptr, keylen); - - /* intentionally corrupt key until mic is installed */ - if (is_tkip) { - key0 = key_v[0] = ~key_v[0]; - key1 = key_v[1] = ~key_v[1]; - } - - for (i = 0; i < ARRAY_SIZE(key_v); i++) - ath5k_hw_reg_write(ah, le32_to_cpu(key_v[i]), - AR5K_KEYTABLE_OFF(entry, i)); + 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; - ath5k_hw_reg_write(ah, keytype, AR5K_KEYTABLE_TYPE(entry)); + /* NOTE: SWBA is different. Having a wrong window there does not + * stop us from sending data and this condition is catched thru + * other means (SWBA interrupt) */ - if (is_tkip) { - /* Install rx/tx MIC */ - rxmic = (__le32 *) &key->key[16]; - txmic = (__le32 *) &key->key[24]; - - if (ah->ah_combined_mic) { - key_v[0] = rxmic[0]; - key_v[1] = cpu_to_le32(le32_to_cpu(txmic[0]) >> 16); - key_v[2] = rxmic[1]; - key_v[3] = cpu_to_le32(le32_to_cpu(txmic[0]) & 0xffff); - key_v[4] = txmic[1]; - } else { - key_v[0] = rxmic[0]; - key_v[1] = 0; - key_v[2] = rxmic[1]; - key_v[3] = 0; - key_v[4] = 0; - } - for (i = 0; i < ARRAY_SIZE(key_v); i++) - ath5k_hw_reg_write(ah, le32_to_cpu(key_v[i]), - AR5K_KEYTABLE_OFF(micentry, i)); - - ath5k_hw_reg_write(ah, AR5K_KEYTABLE_TYPE_NULL, - AR5K_KEYTABLE_TYPE(micentry)); - ath5k_hw_reg_write(ah, 0, AR5K_KEYTABLE_MAC0(micentry)); - ath5k_hw_reg_write(ah, 0, AR5K_KEYTABLE_MAC1(micentry)); - - /* restore first 2 words of key */ - ath5k_hw_reg_write(ah, le32_to_cpu(~key0), - AR5K_KEYTABLE_OFF(entry, 0)); - ath5k_hw_reg_write(ah, le32_to_cpu(~key1), - AR5K_KEYTABLE_OFF(entry, 1)); - } - - return ath5k_hw_set_key_lladdr(ah, entry, mac); -} - -int ath5k_hw_set_key_lladdr(struct ath5k_hw *ah, u16 entry, const u8 *mac) -{ - u32 low_id, high_id; - - /* Invalid entry (key table overflow) */ - AR5K_ASSERT_ENTRY(entry, AR5K_KEYTABLE_SIZE); - - /* - * MAC may be NULL if it's a broadcast key. In this case no need to - * to compute get_unaligned_le32 and get_unaligned_le16 as we - * already know it. - */ - if (!mac) { - low_id = 0xffffffff; - high_id = 0xffff | AR5K_KEYTABLE_VALID; - } else { - low_id = get_unaligned_le32(mac); - high_id = get_unaligned_le16(mac + 4) | AR5K_KEYTABLE_VALID; - } - - ath5k_hw_reg_write(ah, low_id, AR5K_KEYTABLE_MAC0(entry)); - ath5k_hw_reg_write(ah, high_id, AR5K_KEYTABLE_MAC1(entry)); - - return 0; + 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; } /** |