From 573cfde7aaeaadb0fd356ff2a14bdf9238967661 Mon Sep 17 00:00:00 2001 From: Nick Kossifidis Date: Fri, 4 Feb 2011 01:41:02 +0200 Subject: [PATCH] ath5k: Fix fast channel switching Fast channel change fixes: a) Always set OFDM timings b) Don't re-activate PHY c) Enable only NF calibration, not AGC https://bugzilla.kernel.org/show_bug.cgi?id=27382 Signed-off-by: Nick Kossifidis Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath5k/phy.c | 142 +++++++++++++++++++++-------------- 1 file changed, 87 insertions(+), 55 deletions(-) diff --git a/drivers/net/wireless/ath/ath5k/phy.c b/drivers/net/wireless/ath/ath5k/phy.c index c44111f..62ce2f4 100644 --- a/drivers/net/wireless/ath/ath5k/phy.c +++ b/drivers/net/wireless/ath/ath5k/phy.c @@ -282,6 +282,34 @@ int ath5k_hw_phy_disable(struct ath5k_hw *ah) return 0; } +/* + * Wait for synth to settle + */ +static void ath5k_hw_wait_for_synth(struct ath5k_hw *ah, + struct ieee80211_channel *channel) +{ + /* + * On 5211+ read activation -> rx delay + * and use it (100ns steps). + */ + if (ah->ah_version != AR5K_AR5210) { + u32 delay; + delay = ath5k_hw_reg_read(ah, AR5K_PHY_RX_DELAY) & + AR5K_PHY_RX_DELAY_M; + delay = (channel->hw_value & CHANNEL_CCK) ? + ((delay << 2) / 22) : (delay / 10); + if (ah->ah_bwmode == AR5K_BWMODE_10MHZ) + delay = delay << 1; + if (ah->ah_bwmode == AR5K_BWMODE_5MHZ) + delay = delay << 2; + /* XXX: /2 on turbo ? Let's be safe + * for now */ + udelay(100 + delay); + } else { + mdelay(1); + } +} + /**********************\ * RF Gain optimization * @@ -3238,6 +3266,13 @@ int ath5k_hw_phy_init(struct ath5k_hw *ah, struct ieee80211_channel *channel, /* Failed */ if (i >= 100) return -EIO; + + /* Set channel and wait for synth */ + ret = ath5k_hw_channel(ah, channel); + if (ret) + return ret; + + ath5k_hw_wait_for_synth(ah, channel); } /* @@ -3252,13 +3287,53 @@ int ath5k_hw_phy_init(struct ath5k_hw *ah, struct ieee80211_channel *channel, if (ret) return ret; + /* Write OFDM timings on 5212*/ + if (ah->ah_version == AR5K_AR5212 && + channel->hw_value & CHANNEL_OFDM) { + + ret = ath5k_hw_write_ofdm_timings(ah, channel); + if (ret) + return ret; + + /* Spur info is available only from EEPROM versions + * greater than 5.3, but the EEPROM routines will use + * static values for older versions */ + if (ah->ah_mac_srev >= AR5K_SREV_AR5424) + ath5k_hw_set_spur_mitigation_filter(ah, + channel); + } + + /* If we used fast channel switching + * we are done, release RF bus and + * fire up NF calibration. + * + * Note: Only NF calibration due to + * channel change, not AGC calibration + * since AGC is still running ! + */ + if (fast) { + /* + * Release RF Bus grant + */ + AR5K_REG_DISABLE_BITS(ah, AR5K_PHY_RFBUS_REQ, + AR5K_PHY_RFBUS_REQ_REQUEST); + + /* + * Start NF calibration + */ + AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL, + AR5K_PHY_AGCCTL_NF); + + return ret; + } + /* * For 5210 we do all initialization using * initvals, so we don't have to modify * any settings (5210 also only supports * a/aturbo modes) */ - if ((ah->ah_version != AR5K_AR5210) && !fast) { + if (ah->ah_version != AR5K_AR5210) { /* * Write initial RF gain settings @@ -3277,22 +3352,6 @@ int ath5k_hw_phy_init(struct ath5k_hw *ah, struct ieee80211_channel *channel, if (ret) return ret; - /* Write OFDM timings on 5212*/ - if (ah->ah_version == AR5K_AR5212 && - channel->hw_value & CHANNEL_OFDM) { - - ret = ath5k_hw_write_ofdm_timings(ah, channel); - if (ret) - return ret; - - /* Spur info is available only from EEPROM versions - * greater than 5.3, but the EEPROM routines will use - * static values for older versions */ - if (ah->ah_mac_srev >= AR5K_SREV_AR5424) - ath5k_hw_set_spur_mitigation_filter(ah, - channel); - } - /*Enable/disable 802.11b mode on 5111 (enable 2111 frequency converter + CCK)*/ if (ah->ah_radio == AR5K_RF5111) { @@ -3323,47 +3382,20 @@ int ath5k_hw_phy_init(struct ath5k_hw *ah, struct ieee80211_channel *channel, */ ath5k_hw_reg_write(ah, AR5K_PHY_ACT_ENABLE, AR5K_PHY_ACT); + ath5k_hw_wait_for_synth(ah, channel); + /* - * On 5211+ read activation -> rx delay - * and use it. + * Perform ADC test to see if baseband is ready + * Set tx hold and check adc test register */ - if (ah->ah_version != AR5K_AR5210) { - u32 delay; - delay = ath5k_hw_reg_read(ah, AR5K_PHY_RX_DELAY) & - AR5K_PHY_RX_DELAY_M; - delay = (channel->hw_value & CHANNEL_CCK) ? - ((delay << 2) / 22) : (delay / 10); - if (ah->ah_bwmode == AR5K_BWMODE_10MHZ) - delay = delay << 1; - if (ah->ah_bwmode == AR5K_BWMODE_5MHZ) - delay = delay << 2; - /* XXX: /2 on turbo ? Let's be safe - * for now */ - udelay(100 + delay); - } else { - mdelay(1); - } - - if (fast) - /* - * Release RF Bus grant - */ - AR5K_REG_DISABLE_BITS(ah, AR5K_PHY_RFBUS_REQ, - AR5K_PHY_RFBUS_REQ_REQUEST); - else { - /* - * Perform ADC test to see if baseband is ready - * Set tx hold and check adc test register - */ - phy_tst1 = ath5k_hw_reg_read(ah, AR5K_PHY_TST1); - ath5k_hw_reg_write(ah, AR5K_PHY_TST1_TXHOLD, AR5K_PHY_TST1); - for (i = 0; i <= 20; i++) { - if (!(ath5k_hw_reg_read(ah, AR5K_PHY_ADC_TEST) & 0x10)) - break; - udelay(200); - } - ath5k_hw_reg_write(ah, phy_tst1, AR5K_PHY_TST1); + phy_tst1 = ath5k_hw_reg_read(ah, AR5K_PHY_TST1); + ath5k_hw_reg_write(ah, AR5K_PHY_TST1_TXHOLD, AR5K_PHY_TST1); + for (i = 0; i <= 20; i++) { + if (!(ath5k_hw_reg_read(ah, AR5K_PHY_ADC_TEST) & 0x10)) + break; + udelay(200); } + ath5k_hw_reg_write(ah, phy_tst1, AR5K_PHY_TST1); /* * Start automatic gain control calibration -- 2.7.4