On Tue, Oct 13, 2026 at 4:16 AM О К <[email protected]> wrote:
>
> From: ukrainer8 <[email protected]>
> Subject: [PATCH] drm/radeon: retry UVD v1 init on failure after resume
>
> On Evergreen/Redwood (and likely other UVD v1/v2 hardware), resume from
> suspend intermittently fails the UVD ring test:
>
> radeon 0000:01:00.0: [drm] *ERROR* radeon: ring 5 test failed (0xCAFEDEAD)
> radeon 0000:01:00.0: failed initializing UVD (-22).
>
> Cold boot always succeeds; resume succeeds only in about half of the cycles
> (42 measured suspend/resume cycles on a Radeon HD 5650M: OK counts per
> 6-cycle run were 2, 3, 5, 6, 1, 5, 3). Once the ring test fails, UVD stays
> dead for the rest of the session and hardware video decode silently falls
> back to CPU.
>
> The resume path runs the same full asic startup as cold boot
> (evergreen_resume() -> evergreen_startup()), so the difference is the
> hardware state at entry, not a skipped call. The single 100 ms ring-test
> window right after VCPU boot simply races the hardware coming out of
> D3 + ASIC reset.
>
> Retry the init sequence instead of giving up: on failure of clock setup,
> VCPU start or the ring test, fully stop UVD, let it settle for 20 ms and
> try again (up to 3 attempts). Each retry logs the failing step and the
> attempt number, which also makes future reports of this failure mode
> self-diagnosing.
>
> On the same machine the patched driver went 6/6 OK, with the log showing
> the ring test failing on attempts 1-2 and succeeding on attempt 3 — i.e.
> the retry caught exactly the failure the stock driver used to declare
> fatal.
>
> Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1867
> Link: https://bugs.launchpad.net/bugs/1865130
> Tested-by: ukrainer8 <[email protected]> # Radeon
> HD 5650M, kernel 7.0.0
> Signed-off-by: ukrainer8 <[email protected]>
> ---
> drivers/gpu/drm/radeon/uvd_v1_0.c | <diffstat>
> --- a/drivers/gpu/drm/radeon/uvd_v1_0.c
> +++ b/drivers/gpu/drm/radeon/uvd_v1_0.c
> @@ -158,24 +158,45 @@
> {
> struct radeon_ring *ring = &rdev->ring[R600_RING_TYPE_UVD_INDEX];
> uint32_t tmp;
> - int r;
> + int r, retry;
>
> - /* raise clocks while booting up the VCPU */
> - if (rdev->family < CHIP_RV740)
> - radeon_set_uvd_clocks(rdev, 10000, 10000);
> - else
> - radeon_set_uvd_clocks(rdev, 53300, 40000);
> + /* after resume the first ring test can race with the hardware; retry */
> + for (retry = 0; retry < 3; retry++) {
> + /* raise clocks while booting up the VCPU */
> + if (rdev->family < CHIP_RV740)
> + r = radeon_set_uvd_clocks(rdev, 10000, 10000);
> + else
> + r = radeon_set_uvd_clocks(rdev, 53300, 40000);
> + if (r)
> + drm_warn(&rdev->ddev, "radeon: raising UVD clocks failed (%d), attempt
> %d\n",
> + r, retry + 1);
>
> - r = uvd_v1_0_start(rdev);
> - if (r)
> - goto done;
> + if (!r) {
> + r = uvd_v1_0_start(rdev);
> + if (r)
> + drm_warn(&rdev->ddev, "radeon: starting UVD failed (%d), attempt %d\n",
> + r, retry + 1);
> + }
>
> - ring->ready = true;
> - r = radeon_ring_test(rdev, R600_RING_TYPE_UVD_INDEX, ring);
> - if (r) {
> - ring->ready = false;
> - goto done;
> + if (!r) {
> + ring->ready = true;
> + r = radeon_ring_test(rdev, R600_RING_TYPE_UVD_INDEX, ring);
> + if (r) {
> + ring->ready = false;
> + drm_warn(&rdev->ddev, "radeon: UVD ring test failed (%d), attempt %d\n",
> + r, retry + 1);
> + }
> + }
> +
> + if (!r)
> + break;
> +
> + uvd_v1_0_stop(rdev);
> + if (retry < 2)
> + mdelay(20);
> }
> + if (r)
> + goto done;
Your mailer seems to have mangled this patch. Can you try and send it
again, ideally using git-send-email?
Thanks!
Alex
>
> r = radeon_ring_lock(rdev, ring, 10);
> if (r) {
