drm/amd/display: Include udelay when waiting for INBOX0 ACK

commit 3c9ea68cb61bd7e5bd312c06a12adada74ff5805 upstream.

When waiting for the ACK for INBOX0 message,
we have to ensure to include the udelay
for proper wait time

Cc: stable@vger.kernel.org # 6.1+
Reviewed-by: Samson Tam <samson.tam@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alvin Lee <alvin.lee2@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c b/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
index c332787..f58803d 100644 (file)
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
@@ -964,6 +964,7 @@ enum dmub_status dmub_srv_wait_for_inbox0_ack(struct dmub_srv *dmub, uint32_t ti
                ack = dmub->hw_funcs.read_inbox0_ack_register(dmub);
                if (ack)
                        return DMUB_STATUS_OK;
+               udelay(1);
        }
        return DMUB_STATUS_TIMEOUT;
 }