From: Maxime Ripard maxime@cerno.tech
stable inclusion from stable-v5.10.121 commit ac904216b8b8afbd9958642ae31479c535cb4645 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6CQ
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 234998df929f14d00cbf2f1e81a7facb69fd9266 ]
The TXP_VSTART_AT_EOF will generate a second VSTART signal to the HVS. However, the HVS waits for VSTART to enable the FIFO and will thus start filling the FIFO before the start of the frame.
This leads to corruption at the beginning of the first frame, and content from the previous frame at the beginning of the next frames.
Since one VSTART is enough, let's get rid of it.
Fixes: 008095e065a8 ("drm/vc4: Add support for the transposer block") Signed-off-by: Maxime Ripard maxime@cerno.tech Acked-by: Thomas Zimmermann tzimmermann@suse.de Link: https://lore.kernel.org/r/20220328153659.2382206-3-maxime@cerno.tech Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Acked-by: Xie XiuQi xiexiuqi@huawei.com --- drivers/gpu/drm/vc4/vc4_txp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/vc4/vc4_txp.c b/drivers/gpu/drm/vc4/vc4_txp.c index d13502ae973d..d4e750cf3c02 100644 --- a/drivers/gpu/drm/vc4/vc4_txp.c +++ b/drivers/gpu/drm/vc4/vc4_txp.c @@ -295,7 +295,7 @@ static void vc4_txp_connector_atomic_commit(struct drm_connector *conn, if (WARN_ON(i == ARRAY_SIZE(drm_fmts))) return;
- ctrl = TXP_GO | TXP_VSTART_AT_EOF | TXP_EI | + ctrl = TXP_GO | TXP_EI | VC4_SET_FIELD(0xf, TXP_BYTE_ENABLE) | VC4_SET_FIELD(txp_fmts[i], TXP_FORMAT);