On Friday, November 05, 2010, Luis R. Rodriguez wrote: > On Fri, Nov 05, 2010 at 01:50:02PM -0700, Rafael J. Wysocki wrote: > > Hi, > > > > For some time I've been experiencing a regression associated with ath9k > > that occasionally it drops the connection with the AP and goes into a state > > in which reading from its PCI config registers (as done by lspci) return all > > ones. > > > > It may be sort of brought back to life by a suspend/resume afterwards, but > > then the driver cannot really handle it and realoding the driver doesn't help > > (probe fails). Basically, full machine reboot is needed to revive the adapter. > > > > The device is: > > > > 09:00.0 Network controller: Atheros Communications Inc. AR928X Wireless Network Adapter (PCI-Express) (rev 01) > > Subsystem: Foxconn International, Inc. Device e01f > > > > and the kernel says: > > > > [ 9.623217] ath9k 0000:09:00.0: PCI INT A -> GSI 19 (level, low) -> IRQ 19 > > [ 9.631518] ath9k 0000:09:00.0: setting latency timer to 64 > > [ 10.071497] ath: EEPROM regdomain: 0x65 > > [ 10.071502] ath: EEPROM indicates we should expect a direct regpair map > > [ 10.071510] ath: Country alpha2 being used: 00 > > [ 10.071514] ath: Regpair used: 0x65 > > [ 10.096025] phy0: Selected rate control algorithm 'ath9k_rate_control' > > [ 10.097803] Registered led device: ath9k-phy0::radio > > [ 10.098035] Registered led device: ath9k-phy0::assoc > > [ 10.098249] Registered led device: ath9k-phy0::tx > > [ 10.098483] Registered led device: ath9k-phy0::rx > > [ 10.098496] phy0: Atheros AR9280 Rev:2 mem=0xffffc900017e0000, irq=19 > > > > The issue is not really bisectable, because I'm unable to trigger it on demand > > and it occurs approx. 1-2 times a day. So, if you have any ideas what to test, > > please let me know. > > > > It is not reproducible with the 2.6.35 kernel. > > Please try this patch. It _appears_ to help. At least I haven't been able to reproduce the problem since I applied it, which was on Saturday early in the morning. Still, I also haven't used wireless a lot since that time, because I've been traveling mostly. Thanks, Rafael > From: Vasanthakumar Thiagarajan <vasanth@xxxxxxxxxxx> > Date: Tue, 2 Nov 2010 23:57:34 -0700 > Subject: [PATCH] ath9k_hw: Fix AR9280 surprise removal during frequent idle on/off > > Bit 22 of AR_WA should be set to fix the situation where chip reset > is asynchronous to clock of analog shift registers, such that when > reset is released, it could mess up the values of analog shift registers > and cause some hw issue on AR9280. > > This bit is write only, but the driver does a read-modify-write > on AR_WA without setting bit 22 in ar9002_hw_configpcipowersave() > during radio disable. This causes surprise removal of hw. It can > never recover from this state and the hw will become usable only > after a power on/off cycle, and sometimes only during a cold reboot. > > This issue can be triggered by doing frequent roaming with the > simple/test-roam script available from the wifi-test project [1] > when roaming between APs quickly. When roaming there is a is a high > possibility that the device being put into idle (radio disable) state > by mac80211 during AUTH->ASSOC. A device hardware reset would fail > and the kernel would output: > > [40251.363799] ath: AWAKE -> FULL-SLEEP > [40251.363815] ieee80211 phy17: device no longer idle - working > [40251.363817] ath: Marking phy17 as not-idle > [40251.363819] ath: FULL-SLEEP -> AWAKE > [40251.415978] pciehp 0000:00:1c.3:pcie04: Card not present on Slot(3) > [40251.419896] ath: ah->misc_mode 0x4 > [40251.428138] pciehp 0000:00:1c.3:pcie04: Card present on Slot(3) > [40251.532247] ath: timeout (100000 us) on reg 0x9860: 0xffffffff & 0x00000001 != 0x00000000 > [40251.532250] ath: Unable to reset channel (2462 MHz), reset status -5 > [40251.532422] ath: Set channel: 5745 MHz > [40251.540639] ath: Failed to stop TX DMA in 100 msec after killing last frame > [40251.548826] ath: Failed to stop TX DMA in 100 msec after killing last frame > [40251.557023] ath: Failed to stop TX DMA in 100 msec after killing last frame > [40251.565211] ath: Failed to stop TX DMA in 100 msec after killing last frame > [40251.573415] ath: Failed to stop TX DMA in 100 msec after killing last frame > [40251.581603] ath: Failed to stop TX DMA in 100 msec after killing last frame > [40251.581606] ath: Failed to stop TX DMA. Resetting hardware! > [40251.592679] ath: DMA failed to stop in 10 ms AR_CR=0xffffffff AR_DIAG_SW=0xffffffff > [40251.703330] ath: timeout (100000 us) on reg 0x7000: 0xffffffff & 0x00000003 != 0x00000000 > [40251.703333] ath: RTC stuck in MAC reset > [40251.703334] ath: Chip reset failed > [40251.703335] ath: Unable to reset hardware; reset status -22 > > This is currently only reproducible with some HB92 (Half Mini-PCIE) > cards but the fix applies to all AR9280 cards. This patch fixes this > issue by setting bit 22 during radio disable. > > [1] http://wireless.kernel.org/en/developers/Testing/wifi-test > > Cc: Amod.bodas@xxxxxxxxxxx > Cc: David.Quan@xxxxxxxxxxx > Cc: Kyungwan.Nam@xxxxxxxxxxx > Cc: stable@xxxxxxxxxx > Signed-off-by: Vasanthakumar Thiagarajan <vasanth@xxxxxxxxxxx> > --- > drivers/net/wireless/ath/ath9k/ar9002_hw.c | 3 +++ > drivers/net/wireless/ath/ath9k/reg.h | 1 + > 2 files changed, 4 insertions(+), 0 deletions(-) > > diff --git a/drivers/net/wireless/ath/ath9k/ar9002_hw.c b/drivers/net/wireless/ath/ath9k/ar9002_hw.c > index a0471f2..48261b7 100644 > --- a/drivers/net/wireless/ath/ath9k/ar9002_hw.c > +++ b/drivers/net/wireless/ath/ath9k/ar9002_hw.c > @@ -410,6 +410,9 @@ static void ar9002_hw_configpcipowersave(struct ath_hw *ah, > val &= ~(AR_WA_BIT6 | AR_WA_BIT7); > } > > + if (AR_SREV_9280(ah)) > + val |= AR_WA_BIT22; > + > if (AR_SREV_9285E_20(ah)) > val |= AR_WA_BIT23; > > diff --git a/drivers/net/wireless/ath/ath9k/reg.h b/drivers/net/wireless/ath/ath9k/reg.h > index 42976b0..fa05b71 100644 > --- a/drivers/net/wireless/ath/ath9k/reg.h > +++ b/drivers/net/wireless/ath/ath9k/reg.h > @@ -703,6 +703,7 @@ > #define AR_WA_RESET_EN (1 << 18) /* Sw Control to enable PCI-Reset to POR (bit 15) */ > #define AR_WA_ANALOG_SHIFT (1 << 20) > #define AR_WA_POR_SHORT (1 << 21) /* PCI-E Phy reset control */ > +#define AR_WA_BIT22 (1 << 22) > #define AR9285_WA_DEFAULT 0x004a050b > #define AR9280_WA_DEFAULT 0x0040073b > #define AR_WA_DEFAULT 0x0000073f > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
