From 0a8d7cb0c8182df7a28ad719780071178c386f0f Mon Sep 17 00:00:00 2001 From: Senthil Balasubramanian Date: Wed, 22 Dec 2010 19:17:18 +0530 Subject: [PATCH] ath9k_hw: read and backup AR_WA register value even before chip reset on. We need to read and backup AR_WA register value permanently and reading this after the chip is awakened results in this register being zeroed out. This seems to fix the ASPM with L1 enabled issue that we have observed. The laptop becomes very slow and hangs mostly with ASPM L1 enabled without this fix. Cc: Stable Kernel Signed-off-by: Senthil Balasubramanian Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/hw.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c index c0838c2..bc92b45 100644 --- a/drivers/net/wireless/ath/ath9k/hw.c +++ b/drivers/net/wireless/ath/ath9k/hw.c @@ -494,6 +494,15 @@ static int __ath9k_hw_init(struct ath_hw *ah) ath9k_hw_read_revisions(ah); + /* + * Read back AR_WA into a permanent copy and set bits 14 and 17. + * We need to do this to avoid RMW of this register. We cannot + * read the reg when chip is asleep. + */ + ah->WARegVal = REG_READ(ah, AR_WA); + ah->WARegVal |= (AR_WA_D3_L1_DISABLE | + AR_WA_ASPM_TIMER_BASED_DISABLE); + if (!ath9k_hw_set_reset_reg(ah, ATH9K_RESET_POWER_ON)) { ath_err(common, "Couldn't reset chip\n"); return -EIO; @@ -562,14 +571,6 @@ static int __ath9k_hw_init(struct ath_hw *ah) ath9k_hw_init_mode_regs(ah); - /* - * Read back AR_WA into a permanent copy and set bits 14 and 17. - * We need to do this to avoid RMW of this register. We cannot - * read the reg when chip is asleep. - */ - ah->WARegVal = REG_READ(ah, AR_WA); - ah->WARegVal |= (AR_WA_D3_L1_DISABLE | - AR_WA_ASPM_TIMER_BASED_DISABLE); if (ah->is_pciexpress) ath9k_hw_configpcipowersave(ah, 0, 0); -- 2.7.4