Merge branch 'sched-wait-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[linux.git] / drivers / gpu / drm / amd / amdgpu / amdgpu_virt.c

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
index b832651d21375313bf7ed8c60d2efff41438fe7f..21adb1b6e5cb73f593dd3e5d5b84c7eac8811632 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
@@ -22,7 +22,9 @@
  */
 
 #include "amdgpu.h"
-#define MAX_KIQ_REG_WAIT       100000000 /* in usecs */
+#define MAX_KIQ_REG_WAIT       5000 /* in usecs, 5ms */
+#define MAX_KIQ_REG_BAILOUT_INTERVAL   5 /* in msecs, 5ms */
+#define MAX_KIQ_REG_TRY 20
 
 uint64_t amdgpu_csa_vaddr(struct amdgpu_device *adev)
 {
@@ -137,9 +139,9 @@ 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;
+       signed long r, cnt = 0;
        unsigned long flags;
-       uint32_t val, seq;
+       uint32_t seq;
        struct amdgpu_kiq *kiq = &adev->gfx.kiq;
        struct amdgpu_ring *ring = &kiq->ring;
 
@@ -153,18 +155,39 @@ uint32_t amdgpu_virt_kiq_rreg(struct amdgpu_device *adev, uint32_t reg)
        spin_unlock_irqrestore(&kiq->ring_lock, flags);
 
        r = amdgpu_fence_wait_polling(ring, seq, MAX_KIQ_REG_WAIT);
-       if (r < 1) {
-               DRM_ERROR("wait for kiq fence error: %ld\n", r);
-               return ~0;
+
+       /* don't wait anymore for gpu reset case because this way may
+        * block gpu_recover() routine forever, e.g. this virt_kiq_rreg
+        * is triggered in TTM and ttm_bo_lock_delayed_workqueue() will
+        * never return if we keep waiting in virt_kiq_rreg, which cause
+        * gpu_recover() hang there.
+        *
+        * also don't wait anymore for IRQ context
+        * */
+       if (r < 1 && (adev->in_gpu_reset || in_interrupt()))
+               goto failed_kiq_read;
+
+       if (in_interrupt())
+               might_sleep();
+
+       while (r < 1 && cnt++ < MAX_KIQ_REG_TRY) {
+               msleep(MAX_KIQ_REG_BAILOUT_INTERVAL);
+               r = amdgpu_fence_wait_polling(ring, seq, MAX_KIQ_REG_WAIT);
        }
-       val = adev->wb.wb[adev->virt.reg_val_offs];
 
-       return val;
+       if (cnt > MAX_KIQ_REG_TRY)
+               goto failed_kiq_read;
+
+       return adev->wb.wb[adev->virt.reg_val_offs];
+
+failed_kiq_read:
+       pr_err("failed to read reg:%x\n", reg);
+       return ~0;
 }
 
 void amdgpu_virt_kiq_wreg(struct amdgpu_device *adev, uint32_t reg, uint32_t v)
 {
-       signed long r;
+       signed long r, cnt = 0;
        unsigned long flags;
        uint32_t seq;
        struct amdgpu_kiq *kiq = &adev->gfx.kiq;
@@ -180,8 +203,34 @@ void amdgpu_virt_kiq_wreg(struct amdgpu_device *adev, uint32_t reg, uint32_t v)
        spin_unlock_irqrestore(&kiq->ring_lock, flags);
 
        r = amdgpu_fence_wait_polling(ring, seq, MAX_KIQ_REG_WAIT);
-       if (r < 1)
-               DRM_ERROR("wait for kiq fence error: %ld\n", r);
+
+       /* don't wait anymore for gpu reset case because this way may
+        * block gpu_recover() routine forever, e.g. this virt_kiq_rreg
+        * is triggered in TTM and ttm_bo_lock_delayed_workqueue() will
+        * never return if we keep waiting in virt_kiq_rreg, which cause
+        * gpu_recover() hang there.
+        *
+        * also don't wait anymore for IRQ context
+        * */
+       if (r < 1 && (adev->in_gpu_reset || in_interrupt()))
+               goto failed_kiq_write;
+
+       if (in_interrupt())
+               might_sleep();
+
+       while (r < 1 && cnt++ < MAX_KIQ_REG_TRY) {
+
+               msleep(MAX_KIQ_REG_BAILOUT_INTERVAL);
+               r = amdgpu_fence_wait_polling(ring, seq, MAX_KIQ_REG_WAIT);
+       }
+
+       if (cnt > MAX_KIQ_REG_TRY)
+               goto failed_kiq_write;
+
+       return;
+
+failed_kiq_write:
+       pr_err("failed to write reg:%x\n", reg);
 }
 
 /**