Re: [PATCH 6.18 085/314] media: verisilicon: Avoid G2 bus error while decoding H.264 and HEVC

Sebastian Krzyszkowiak
2026-03-11T00:44:19Z

On wtorek, 10 marca 2026 12:15:44 czas środkowoeuropejski standardowy Sasha
Levin wrote:
> From: Ming Qian <ming.qian@oss.nxp.com>
>
> [ Upstream commit e0203ddf9af7c8e170e1e99ce83b4dc07f0cd765 ]
>
> For the i.MX8MQ platform, there is a hardware limitation: the g1 VPU and
> g2 VPU cannot decode simultaneously; otherwise, it will cause below bus
> error and produce corrupted pictures, even potentially lead to system hang.
>
> [ 110.527986] hantro-vpu 38310000.video-codec: frame decode timed out.
> [ 110.583517] hantro-vpu 38310000.video-codec: bus error detected.
>
> Therefore, it is necessary to ensure that g1 and g2 operate alternately.
> This allows for successful multi-instance decoding of H.264 and HEVC.
>
> To achieve this, g1 and g2 share the same v4l2_m2m_dev, and then the
> v4l2_m2m_dev can handle the scheduling.
>
> Fixes: cb5dd5a0fa518 ("media: hantro: Introduce G2/HEVC decoder")
> Cc: stable@vger.kernel.org
> Signed-off-by: Ming Qian <ming.qian@oss.nxp.com>
> Reviewed-by: Frank Li <Frank.Li@nxp.com>
> Co-developed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
> Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
> Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
> drivers/media/platform/verisilicon/hantro.h | 2 +
> .../media/platform/verisilicon/hantro_drv.c | 42 +++++++++++++++++--
> .../media/platform/verisilicon/imx8m_vpu_hw.c | 8 ++++
> 3 files changed, 49 insertions(+), 3 deletions(-)
>

This one introduces a regression that's being fixed in https://lore.kernel.org/
lkml/20260306031059.801-1-ming.qian@oss.nxp.com/T/, so they should probably be
applied together once the fix lands.