drm/amdgpu: busywait KIQ register accessing (v4)
Register accessing is performed when IRQ is disabled. Never sleep in
this function.
Known issue: dead sleep in many use cases of index/data registers.
v2:
- wrap polling fence functions.
- don't trigger IRQ for polling in case of wrongly fence signal.
v3:
- handle wrap round gracefully.
- add comments for polling function
v4:
- don't return negative timeout confused with error code
Signed-off-by: pding <Pixel.Ding@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
index ed7be2e..e97f80f 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
@@ -22,7 +22,7 @@
*/
#include "amdgpu.h"
-#define MAX_KIQ_REG_WAIT 100000
+#define MAX_KIQ_REG_WAIT 100000000 /* in usecs */
int amdgpu_allocate_static_csa(struct amdgpu_device *adev)
{
@@ -114,27 +114,24 @@ void amdgpu_virt_init_setting(struct amdgpu_device *adev)
uint32_t amdgpu_virt_kiq_rreg(struct amdgpu_device *adev, uint32_t reg)
{
signed long r;
- uint32_t val;
- struct dma_fence *f;
+ uint32_t val, seq;
struct amdgpu_kiq *kiq = &adev->gfx.kiq;
struct amdgpu_ring *ring = &kiq->ring;
BUG_ON(!ring->funcs->emit_rreg);
- mutex_lock(&kiq->ring_mutex);
+ spin_lock(&kiq->ring_lock);
amdgpu_ring_alloc(ring, 32);
amdgpu_ring_emit_rreg(ring, reg);
- amdgpu_fence_emit(ring, &f);
+ amdgpu_fence_emit_polling(ring, &seq);
amdgpu_ring_commit(ring);
- mutex_unlock(&kiq->ring_mutex);
+ spin_unlock(&kiq->ring_lock);
- r = dma_fence_wait_timeout(f, false, msecs_to_jiffies(MAX_KIQ_REG_WAIT));
- dma_fence_put(f);
+ r = amdgpu_fence_wait_polling(ring, seq, MAX_KIQ_REG_WAIT);
if (r < 1) {
- DRM_ERROR("wait for kiq fence error: %ld.\n", r);
+ DRM_ERROR("wait for kiq fence error: %ld\n", r);
return ~0;
}
-
val = adev->wb.wb[adev->virt.reg_val_offs];
return val;
@@ -143,23 +140,22 @@ uint32_t amdgpu_virt_kiq_rreg(struct amdgpu_device *adev, uint32_t reg)
void amdgpu_virt_kiq_wreg(struct amdgpu_device *adev, uint32_t reg, uint32_t v)
{
signed long r;
- struct dma_fence *f;
+ uint32_t seq;
struct amdgpu_kiq *kiq = &adev->gfx.kiq;
struct amdgpu_ring *ring = &kiq->ring;
BUG_ON(!ring->funcs->emit_wreg);
- mutex_lock(&kiq->ring_mutex);
+ spin_lock(&kiq->ring_lock);
amdgpu_ring_alloc(ring, 32);
amdgpu_ring_emit_wreg(ring, reg, v);
- amdgpu_fence_emit(ring, &f);
+ amdgpu_fence_emit_polling(ring, &seq);
amdgpu_ring_commit(ring);
- mutex_unlock(&kiq->ring_mutex);
+ spin_unlock(&kiq->ring_lock);
- r = dma_fence_wait_timeout(f, false, msecs_to_jiffies(MAX_KIQ_REG_WAIT));
+ r = amdgpu_fence_wait_polling(ring, seq, MAX_KIQ_REG_WAIT);
if (r < 1)
- DRM_ERROR("wait for kiq fence error: %ld.\n", r);
- dma_fence_put(f);
+ DRM_ERROR("wait for kiq fence error: %ld\n", r);
}
/**