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path: root/drivers/net/wireless/ath/ath5k/pcu.c
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Diffstat (limited to 'drivers/net/wireless/ath/ath5k/pcu.c')
-rw-r--r--drivers/net/wireless/ath/ath5k/pcu.c297
1 files changed, 101 insertions, 196 deletions
diff --git a/drivers/net/wireless/ath/ath5k/pcu.c b/drivers/net/wireless/ath/ath5k/pcu.c
index 86fdb6ddfaaa..074b4c644399 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).
*/
@@ -207,7 +207,8 @@ static int ath5k_hw_set_cts_timeout(struct ath5k_hw *ah, unsigned int timeout)
*/
unsigned int ath5k_hw_htoclock(struct ath5k_hw *ah, unsigned int usec)
{
- return usec * ath5k_hw_get_clockrate(ah);
+ struct ath_common *common = ath5k_hw_common(ah);
+ return usec * common->clockrate;
}
/**
@@ -216,17 +217,19 @@ unsigned int ath5k_hw_htoclock(struct ath5k_hw *ah, unsigned int usec)
*/
unsigned int ath5k_hw_clocktoh(struct ath5k_hw *ah, unsigned int clock)
{
- return clock / ath5k_hw_get_clockrate(ah);
+ struct ath_common *common = ath5k_hw_common(ah);
+ return clock / common->clockrate;
}
/**
- * ath5k_hw_get_clockrate - Get the clock rate for current mode
+ * ath5k_hw_set_clockrate - Set common->clockrate for the current channel
*
* @ah: The &struct ath5k_hw
*/
-unsigned int ath5k_hw_get_clockrate(struct ath5k_hw *ah)
+void ath5k_hw_set_clockrate(struct ath5k_hw *ah)
{
struct ieee80211_channel *channel = ah->ah_current_channel;
+ struct ath_common *common = ath5k_hw_common(ah);
int clock;
if (channel->hw_value & CHANNEL_5GHZ)
@@ -240,7 +243,7 @@ unsigned int ath5k_hw_get_clockrate(struct ath5k_hw *ah)
if (channel->hw_value & CHANNEL_TURBO)
clock *= 2;
- return clock;
+ common->clockrate = clock;
}
/**
@@ -308,27 +311,26 @@ 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 +498,10 @@ 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 +524,8 @@ 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 +609,7 @@ 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 +649,95 @@ 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)
-{
- 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;
-
- /*
- * 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));
-
- ath5k_hw_reg_write(ah, keytype, AR5K_KEYTABLE_TYPE(entry));
-
- 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)
+bool
+ath5k_hw_check_beacon_timers(struct ath5k_hw *ah, int intval)
{
- u32 low_id, high_id;
-
- /* Invalid entry (key table overflow) */
- AR5K_ASSERT_ENTRY(entry, AR5K_KEYTABLE_SIZE);
+ unsigned int nbtt, atim, dma;
- /*
- * 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;
- }
+ 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, low_id, AR5K_KEYTABLE_MAC0(entry));
- ath5k_hw_reg_write(ah, high_id, AR5K_KEYTABLE_MAC1(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) */
- 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;
}
/**