4.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ayan Kumar Halder <ayan.halder@xxxxxxx> [ Upstream commit ad7fda2e378f4356df621a39655f7c200b495d81 ] On some Mali-DP processors, the LAYER_FORMAT register contains fields other than the format. These bits were unconditionally cleared when setting the pixel format, whereas they should be preserved at their reset values. Reported-by: Brian Starkey <brian.starkey@xxxxxxx> Reported-by: Liviu Dudau <liviu.dudau@xxxxxxx> Signed-off-by: Ayan Kumar halder <ayan.halder@xxxxxxx> Acked-by: Liviu Dudau <liviu.dudau@xxxxxxx> Signed-off-by: Liviu Dudau <liviu.dudau@xxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/arm/malidp_planes.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/arm/malidp_planes.c +++ b/drivers/gpu/drm/arm/malidp_planes.c @@ -23,6 +23,7 @@ /* Layer specific register offsets */ #define MALIDP_LAYER_FORMAT 0x000 +#define LAYER_FORMAT_MASK 0x3f #define MALIDP_LAYER_CONTROL 0x004 #define LAYER_ENABLE (1 << 0) #define LAYER_FLOWCFG_MASK 7 @@ -337,7 +338,9 @@ static void malidp_de_plane_update(struc dest_w = plane->state->crtc_w; dest_h = plane->state->crtc_h; - malidp_hw_write(mp->hwdev, ms->format, mp->layer->base); + val = malidp_hw_read(mp->hwdev, mp->layer->base); + val = (val & ~LAYER_FORMAT_MASK) | ms->format; + malidp_hw_write(mp->hwdev, val, mp->layer->base); for (i = 0; i < ms->n_planes; i++) { /* calculate the offset for the layer's plane registers */