From: Mika Kuoppala Date: Tue, 12 Nov 2013 12:44:19 +0000 (+0200) Subject: drm/i915: add i915_reset_count X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=2ac0f45099d2d3b8918d63e1bac698b5cb272aa1;p=linux-beck.git drm/i915: add i915_reset_count reset_counter will be incremented twice per successful reset. Odd values mean reset is in progress and even values mean that reset has completed. Reset status ioctl introduced in following commit needs to deliver global reset count to userspace so use reset_counter to derive the actual reset count for the gpu Note that reset in progress is enough to increment the counter. v2: wedged equals reset in progress (Daniel Vetter) v3: Fixed stale comments (Damien Lespiau) Signed-off-by: Mika Kuoppala Reviewed-by: Damien Lespiau Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index c546316ac649..4c0f751d1c88 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1069,34 +1069,30 @@ struct i915_gpu_error { unsigned long missed_irq_rings; /** - * State variable and reset counter controlling the reset flow + * State variable controlling the reset flow and count * - * Upper bits are for the reset counter. This counter is used by the - * wait_seqno code to race-free noticed that a reset event happened and - * that it needs to restart the entire ioctl (since most likely the - * seqno it waited for won't ever signal anytime soon). + * This is a counter which gets incremented when reset is triggered, + * and again when reset has been handled. So odd values (lowest bit set) + * means that reset is in progress and even values that + * (reset_counter >> 1):th reset was successfully completed. + * + * If reset is not completed succesfully, the I915_WEDGE bit is + * set meaning that hardware is terminally sour and there is no + * recovery. All waiters on the reset_queue will be woken when + * that happens. + * + * This counter is used by the wait_seqno code to notice that reset + * event happened and it needs to restart the entire ioctl (since most + * likely the seqno it waited for won't ever signal anytime soon). * * This is important for lock-free wait paths, where no contended lock * naturally enforces the correct ordering between the bail-out of the * waiter and the gpu reset work code. - * - * Lowest bit controls the reset state machine: Set means a reset is in - * progress. This state will (presuming we don't have any bugs) decay - * into either unset (successful reset) or the special WEDGED value (hw - * terminally sour). All waiters on the reset_queue will be woken when - * that happens. */ atomic_t reset_counter; - /** - * Special values/flags for reset_counter - * - * Note that the code relies on - * I915_WEDGED & I915_RESET_IN_PROGRESS_FLAG - * being true. - */ #define I915_RESET_IN_PROGRESS_FLAG 1 -#define I915_WEDGED 0xffffffff +#define I915_WEDGED (1 << 31) /** * Waitqueue to signal when the reset has completed. Used by clients @@ -2046,12 +2042,17 @@ int __must_check i915_gem_check_wedge(struct i915_gpu_error *error, static inline bool i915_reset_in_progress(struct i915_gpu_error *error) { return unlikely(atomic_read(&error->reset_counter) - & I915_RESET_IN_PROGRESS_FLAG); + & (I915_RESET_IN_PROGRESS_FLAG | I915_WEDGED)); } static inline bool i915_terminally_wedged(struct i915_gpu_error *error) { - return atomic_read(&error->reset_counter) == I915_WEDGED; + return atomic_read(&error->reset_counter) & I915_WEDGED; +} + +static inline u32 i915_reset_count(struct i915_gpu_error *error) +{ + return ((atomic_read(&error->reset_counter) & ~I915_WEDGED) + 1) / 2; } void i915_gem_reset(struct drm_device *dev); diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index e14285bafbd4..19949e8b36c5 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -1781,7 +1781,7 @@ static void i915_error_work_func(struct work_struct *work) kobject_uevent_env(&dev->primary->kdev.kobj, KOBJ_CHANGE, reset_done_event); } else { - atomic_set(&error->reset_counter, I915_WEDGED); + atomic_set_mask(I915_WEDGED, &error->reset_counter); } /*