drm/nouveau/tmr: detect stalled gpu timer and break out of waits (e4f90a35) · Commits · github.com / kvm-riscv / linux

drivers/gpu/drm/nouveau/include/nvkm/subdev/timer.h

+18 −10

Original line number	Diff line number	Diff line
		@@ -28,6 +28,18 @@ struct nvkm_timer {
		u64 nvkm_timer_read(struct nvkm_timer *);
		void nvkm_timer_alarm(struct nvkm_timer , u32 nsec, struct nvkm_alarm );

		struct nvkm_timer_wait {
		struct nvkm_timer *tmr;
		u64 limit;
		u64 time0;
		u64 time1;
		int reads;
		};

		void nvkm_timer_wait_init(struct nvkm_device *, u64 nsec,
		struct nvkm_timer_wait *);
		s64 nvkm_timer_wait_test(struct nvkm_timer_wait *);

		/* Delay based on GPU time (ie. PTIMER).
		*
		* Will return -ETIMEDOUT unless the loop was terminated with 'break',
		@@ -38,21 +50,17 @@ void nvkm_timer_alarm(struct nvkm_timer , u32 nsec, struct nvkm_alarm );
		*/
		#define NVKM_DELAY _warn = false;
		#define nvkm_nsec(d,n,cond...) ({ \
		struct nvkm_device *_device = (d); \
		struct nvkm_timer *_tmr = _device->timer; \
		u64 _nsecs = (n), _time0 = nvkm_timer_read(_tmr); \
		s64 _taken = 0; \
		struct nvkm_timer_wait _wait; \
		bool _warn = true; \
		s64 _taken = 0; \
		\
		nvkm_timer_wait_init((d), (n), &_wait); \
		do { \
		cond \
		} while (_taken = nvkm_timer_read(_tmr) - _time0, _taken < _nsecs); \
		} while ((_taken = nvkm_timer_wait_test(&_wait)) >= 0); \
		\
		if (_taken >= _nsecs) { \
		if (_warn) \
		dev_WARN(_device->dev, "timeout\n"); \
		_taken = -ETIMEDOUT; \
		} \
		if (_warn && _taken < 0) \
		dev_WARN(_wait.tmr->subdev.device->dev, "timeout\n"); \
		_taken; \
		})
		#define nvkm_usec(d,u,cond...) nvkm_nsec((d), (u) * 1000, ##cond)

+36 −0

Original line number	Diff line number	Diff line
		@@ -23,6 +23,42 @@
		*/
		#include "priv.h"

		s64
		nvkm_timer_wait_test(struct nvkm_timer_wait *wait)
		{
		struct nvkm_subdev *subdev = &wait->tmr->subdev;
		u64 time = nvkm_timer_read(wait->tmr);

		if (wait->reads == 0) {
		wait->time0 = time;
		wait->time1 = time;
		}

		if (wait->time1 == time) {
		if (wait->reads++ == 16) {
		nvkm_fatal(subdev, "stalled at %016llx\n", time);
		return -ETIMEDOUT;
		}
		} else {
		wait->time1 = time;
		wait->reads = 1;
		}

		if (wait->time1 - wait->time0 > wait->limit)
		return -ETIMEDOUT;

		return wait->time1 - wait->time0;
		}

		void
		nvkm_timer_wait_init(struct nvkm_device *device, u64 nsec,
		struct nvkm_timer_wait *wait)
		{
		wait->tmr = device->timer;
		wait->limit = nsec;
		wait->reads = 0;
		}

		u64
		nvkm_timer_read(struct nvkm_timer *tmr)
		{