Re: [PATCH] drm/rockchip: vop: Fix color for RGB888/BGR888 format on VOP full

[Andy Yan <andy.yan@rock-chips.com>]

Hi:

On 10/24/23 16:49, Christopher Obbard wrote:
> Hi Jonas,
>
> On Mon, 2023-10-23 at 21:11 +0000, Jonas Karlman wrote:
>> Use of DRM_FORMAT_RGB888 and DRM_FORMAT_BGR888 on e.g. RK3288, RK3328
>> and RK3399 result in wrong colors being displayed.
>>
>> The issue can be observed using modetest:
>>
>>    modetest -s <connector_id>@<crtc_id>:1920x1080-60@RG24
>>    modetest -s <connector_id>@<crtc_id>:1920x1080-60@BG24
>>
>> Vendor 4.4 kernel apply an inverted rb swap for these formats on VOP
>> full (major = 3).
>>
>> Fix colors by applying rb swap similar to vendor 4.4 kernel.
>>
>> Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
> How about a fixes tag? Seems like this was introduced in commit 85a359f25388
> ("drm/rockchip: Add BGR formats to VOP")
>
>> ---
>>   drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 9 ++++++---
>>   1 file changed, 6 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
>> b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
>> index b3d0b6ae9294..a1ce09a22f83 100644
>> --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
>> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
>> @@ -247,14 +247,17 @@ static inline void vop_cfg_done(struct vop *vop)
>>   	VOP_REG_SET(vop, common, cfg_done, 1);
>>   }
>>   
>> -static bool has_rb_swapped(uint32_t format)
>> +static bool has_rb_swapped(uint32_t version, uint32_t format)
>>   {
>>   	switch (format) {
>>   	case DRM_FORMAT_XBGR8888:
>>   	case DRM_FORMAT_ABGR8888:
>> -	case DRM_FORMAT_BGR888:
>>   	case DRM_FORMAT_BGR565:
>>   		return true;
>> +	case DRM_FORMAT_RGB888:
>> +		return VOP_MAJOR(version) == 3;
>> +	case DRM_FORMAT_BGR888:
>> +		return VOP_MAJOR(version) != 3;
> The hardcoded bits are quite scary as it applies to all hardware variants ;-).
> Is it worth adding an inline comment to describe what is going on and how it
> relates to VOPL and VOPH? Or would it be even better to add this as a quirk in
> the various vop_data structs?


Every vop hardware has a version(including VOPB/VOPL), so I think use 
VOP_MAJOR to distinguish is ok. Of course it's better

to add some comments. As for adding some quirk in vop_data, I have the 
idea of adding a table to describe the drm format and it's (rb/uv swap, 
afbc)

capability, but I think this is can be done in the future.

>
>
> Cheers!
>
> Chris
>
>>   	default:
>>   		return false;
>>   	}
>> @@ -1035,7 +1038,7 @@ static void vop_plane_atomic_update(struct drm_plane
>> *plane,
>>   	VOP_WIN_SET(vop, win, dsp_info, dsp_info);
>>   	VOP_WIN_SET(vop, win, dsp_st, dsp_st);
>>   
>> -	rb_swap = has_rb_swapped(fb->format->format);
>> +	rb_swap = has_rb_swapped(vop->data->version, fb->format->format);
>>   	VOP_WIN_SET(vop, win, rb_swap, rb_swap);
>>   
>>   	/*
> _______________________________________________
> Linux-rockchip mailing list
> Linux-rockchip@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-rockchip