drm/radeon/kms: simplify & improve GPU reset V2

This simplify and improve GPU reset for R1XX-R6XX hw, it's
not 100% reliable here are result:
- R1XX/R2XX works bunch of time in a row, sometimes it
  seems it can work indifinitly
- R3XX/R3XX the most unreliable one, sometimes you will be
  able to reset few times, sometimes not even once
- R5XX more reliable than previous hw, seems to work most
  of the times but once in a while it fails for no obvious
  reasons (same status than previous reset just no same
  happy ending)
- R6XX/R7XX are lot more reliable with this patch, still
  it seems that it can fail after a bunch (reset every
  2sec for 3hour bring down the GPU & computer)

This have been tested on various hw, for some odd reasons
i wasn't able to lockup RS480/RS690 (while they use to
love locking up).

Note that on R1XX-R5XX the cursor will disapear after
lockup haven't checked why, switch to console and back
to X will restore cursor.

Next step is to record the bogus command that leaded to
the lockup.

V2 Fix r6xx resume path to avoid reinitializing blit
module, use the gpu_lockup boolean to avoid entering
inifinite waiting loop on fence while reiniting the GPU

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index 232a3076849..d4ff5a6d349 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -639,6 +639,8 @@ void radeon_device_fini(struct radeon_device *rdev)
 {
 	DRM_INFO("radeon: finishing device.\n");
 	rdev->shutdown = true;
+	/* evict vram memory */
+	radeon_bo_evict_vram(rdev);
 	radeon_fini(rdev);
 	destroy_workqueue(rdev->wq);
 	vga_switcheroo_unregister_client(rdev->pdev);
@@ -737,6 +739,26 @@ int radeon_resume_kms(struct drm_device *dev)
 	return 0;
 }
 
+int radeon_gpu_reset(struct radeon_device *rdev)
+{
+	int r;
+
+	radeon_save_bios_scratch_regs(rdev);
+	radeon_suspend(rdev);
+
+	r = radeon_asic_reset(rdev);
+	if (!r) {
+		dev_info(rdev->dev, "GPU reset succeed\n");
+		radeon_resume(rdev);
+		radeon_restore_bios_scratch_regs(rdev);
+		drm_helper_resume_force_mode(rdev->ddev);
+		return 0;
+	}
+	/* bad news, how to tell it to userspace ? */
+	dev_info(rdev->dev, "GPU reset failed\n");
+	return r;
+}
+
 
 /*
  * Debugfs