Issam Hamdi <ih@xxxxxxxxxxxxxxxxxx> writes:
> From: Simon Wunderlich <simon.wunderlich@xxxxxxxxxxxxx>
>
> QCA 802.11n chips (especially AR9330/AR9340) sometimes end up in a state in
> which a read of AR_CFG always returns 0xdeadbeef. This should not happen
> when when the power_mode of the device is ATH9K_PM_AWAKE.
>
> This problem is not yet detected by any other workaround in ath9k. No way
> is known to reproduce the problem easily.
>
> This patch originally developed by "Simon Wunderlich <simon.wunderlich@xxxxxxxxxxxxx>"
> and "Sven Eckelmann <sven.eckelmann@xxxxxxxxxxxxx>"
>
> Co-developed-by: Simon Wunderlich <sw@xxxxxxxxxxxxxxxxxx>
> Co-developed-by: Sven Eckelmann <se@xxxxxxxxxxxxxxxxxx>
> Signed-off-by: Issam Hamdi <ih@xxxxxxxxxxxxxxxxxx>
> ---
> drivers/net/wireless/ath/ath9k/ath9k.h | 3 +++
> drivers/net/wireless/ath/ath9k/debug.c | 1 +
> drivers/net/wireless/ath/ath9k/debug.h | 1 +
> drivers/net/wireless/ath/ath9k/init.c | 1 +
> drivers/net/wireless/ath/ath9k/link.c | 31 ++++++++++++++++++++++++++
> drivers/net/wireless/ath/ath9k/main.c | 4 ++++
> 6 files changed, 41 insertions(+)
>
> diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
> index 29ca65a732a6..c1ce081445a9 100644
> --- a/drivers/net/wireless/ath/ath9k/ath9k.h
> +++ b/drivers/net/wireless/ath/ath9k/ath9k.h
> @@ -739,11 +739,13 @@ void ath9k_csa_update(struct ath_softc *sc);
> #define ATH_ANI_MAX_SKIP_COUNT 10
> #define ATH_PAPRD_TIMEOUT 100 /* msecs */
> #define ATH_PLL_WORK_INTERVAL 100
> +#define ATH_HANG_WORK_INTERVAL 4000
>
> void ath_hw_check_work(struct work_struct *work);
> void ath_reset_work(struct work_struct *work);
> bool ath_hw_check(struct ath_softc *sc);
> void ath_hw_pll_work(struct work_struct *work);
> +void ath_hw_hang_work(struct work_struct *work);
> void ath_paprd_calibrate(struct work_struct *work);
> void ath_ani_calibrate(struct timer_list *t);
> void ath_start_ani(struct ath_softc *sc);
> @@ -1044,6 +1046,7 @@ struct ath_softc {
> #endif
> struct delayed_work hw_check_work;
> struct delayed_work hw_pll_work;
> + struct delayed_work hw_hang_work;
> struct timer_list sleep_timer;
>
> #ifdef CONFIG_ATH9K_BTCOEX_SUPPORT
> diff --git a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c
> index eff894958a73..6b2469a01f17 100644
> --- a/drivers/net/wireless/ath/ath9k/debug.c
> +++ b/drivers/net/wireless/ath/ath9k/debug.c
> @@ -750,6 +750,7 @@ static int read_file_reset(struct seq_file *file, void *data)
> [RESET_TYPE_CALIBRATION] = "Calibration error",
> [RESET_TX_DMA_ERROR] = "Tx DMA stop error",
> [RESET_RX_DMA_ERROR] = "Rx DMA stop error",
> + [RESET_TYPE_DEADBEEF] = "deadbeef hang",
> };
> int i;
>
> diff --git a/drivers/net/wireless/ath/ath9k/debug.h b/drivers/net/wireless/ath/ath9k/debug.h
> index 389459c04d14..6ebb6053a8c1 100644
> --- a/drivers/net/wireless/ath/ath9k/debug.h
> +++ b/drivers/net/wireless/ath/ath9k/debug.h
> @@ -53,6 +53,7 @@ enum ath_reset_type {
> RESET_TYPE_CALIBRATION,
> RESET_TX_DMA_ERROR,
> RESET_RX_DMA_ERROR,
> + RESET_TYPE_DEADBEEF,
> __RESET_TYPE_MAX
> };
>
> diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c
> index f9e77c4624d9..833474d7281f 100644
> --- a/drivers/net/wireless/ath/ath9k/init.c
> +++ b/drivers/net/wireless/ath/ath9k/init.c
> @@ -740,6 +740,7 @@ static int ath9k_init_softc(u16 devid, struct ath_softc *sc,
> INIT_WORK(&sc->paprd_work, ath_paprd_calibrate);
> INIT_DELAYED_WORK(&sc->hw_pll_work, ath_hw_pll_work);
> INIT_DELAYED_WORK(&sc->hw_check_work, ath_hw_check_work);
> + INIT_DELAYED_WORK(&sc->hw_hang_work, ath_hw_hang_work);
>
> ath9k_init_channel_context(sc);
>
> diff --git a/drivers/net/wireless/ath/ath9k/link.c b/drivers/net/wireless/ath/ath9k/link.c
> index d1e5767aab3c..37438960c278 100644
> --- a/drivers/net/wireless/ath/ath9k/link.c
> +++ b/drivers/net/wireless/ath/ath9k/link.c
> @@ -142,6 +142,37 @@ void ath_hw_pll_work(struct work_struct *work)
> msecs_to_jiffies(ATH_PLL_WORK_INTERVAL));
> }
>
> +static bool ath_hw_hang_deadbeef(struct ath_softc *sc)
> +{
> + struct ath_common *common = ath9k_hw_common(sc->sc_ah);
> + u32 reg;
> +
> + /* check for stucked MAC */
> + ath9k_ps_wakeup(sc);
> + reg = REG_READ(sc->sc_ah, AR_CFG);
> + ath9k_ps_restore(sc);
> +
> + if (reg != 0xdeadbeef)
> + return false;
ath9k_hw_check_alive() already does this exact check...
-Toke
