drm/exynos: soft reset mixer before reconfigure after power-on

Mixer soft reset is a recommended step before reconfiguring
the mixer after power on. Mixer looses the previous state of
DMAs if soft reset. This is the recommendation from the
hardware team.

Signed-off-by: Rahul Sharma <rahul.sharma@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

diff --git a/drivers/gpu/drm/exynos/exynos_mixer.c b/drivers/gpu/drm/exynos/exynos_mixer.c
index 6773b03..6f18581 100644 (file)
--- a/drivers/gpu/drm/exynos/exynos_mixer.c
+++ b/drivers/gpu/drm/exynos/exynos_mixer.c
@@ -1085,6 +1085,8 @@ static void mixer_poweron(struct exynos_drm_manager *mgr)
        ctx->powered = true;
        mutex_unlock(&ctx->mixer_mutex);
 
+       mixer_reg_writemask(res, MXR_STATUS, ~0, MXR_STATUS_SOFT_RESET);
+
        mixer_reg_write(res, MXR_INT_EN, ctx->int_en);
        mixer_win_reset(ctx);