Re: [PATCH i-g-t 3/4] tests/kms_atomic: Add solid fill plane subtest

[Jessica Zhang <quic_jesszhan@quicinc.com>]

On 12/18/2023 2:12 AM, Pekka Paalanen wrote:
> On Fri, 15 Dec 2023 16:40:23 -0800
> Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
> 
>> Add a basic test for solid fill planes.
>>
>> This test will first commit a single-color framebuffer plane then
>> a solid fill plane with the same contents. It then validates the solid
>> fill plane by comparing the resulting CRC with the CRC of the reference
>> framebuffer commit.
>>
>> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
>> ---
>>   tests/kms_atomic.c | 94 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 94 insertions(+)
>>
>> diff --git a/tests/kms_atomic.c b/tests/kms_atomic.c
>> old mode 100644
>> new mode 100755
>> index 2b6e9a8f0383..8f81e65ad84f
>> --- a/tests/kms_atomic.c
>> +++ b/tests/kms_atomic.c
>> @@ -128,6 +128,13 @@ enum kms_atomic_check_relax {
>>   	PLANE_RELAX_FB = (1 << 1)
>>   };
>>   
>> +struct solid_fill_blob {
>> +	uint32_t r;
>> +	uint32_t g;
>> +	uint32_t b;
>> +	uint32_t pad;
>> +};
>> +
>>   static inline int damage_rect_width(struct drm_mode_rect *r)
>>   {
>>   	return r->x2 - r->x1;
>> @@ -1322,6 +1329,79 @@ static void atomic_plane_damage(data_t *data)
>>   	igt_remove_fb(data->drm_fd, &fb_2);
>>   }
>>   
>> +static void test_solid_fill_plane(data_t *data, igt_output_t *output,  igt_plane_t *plane)
>> +{
>> +	struct drm_mode_create_blob c;
>> +	struct drm_mode_destroy_blob d;
>> +	drmModeModeInfo *mode = igt_output_get_mode(output);
>> +	struct drm_mode_rect rect = { 0 };
>> +	struct igt_fb ref_fb;
>> +	igt_pipe_crc_t *pipe_crc;
>> +	igt_crc_t ref_crc, new_crc;
>> +	enum pipe pipe = data->pipe->pipe;
>> +	int height, width;
>> +	int ret;
>> +
>> +	struct solid_fill_blob blob_data = {
>> +		.r = 0x00000000,
>> +		.g = 0x00000000,
>> +		.b = 0xff000000,
>> +		.pad = 0x0,
>> +	};
> 
> Hi Jessica!
> 
> This is the blob sent to KMS as the solid fill color...
> 
> ...
> 
>> +	igt_create_color_fb(data->drm_fd, width, height,
>> +			    DRM_FORMAT_XRGB8888, DRM_FORMAT_MOD_LINEAR,
>> +			    0.0, 0.0, 1.0, &ref_fb);
> 
> ..and this (0.0, 0.0, 1.0) is the corresponding color in normalized
> values, I presume.
> 
> So you say that 0xff000000 = 1.0.
> 
> However, the patch for the kernel UAPI header says this:
> 
> +/**
> + * struct drm_mode_solid_fill - User info for solid fill planes
> + *
> + * This is the userspace API solid fill information structure.
> + *
> + * Userspace can enable solid fill planes by assigning the plane "solid_fill"
> + * property to a blob containing a single drm_mode_solid_fill struct populated with an RGB323232
> + * color and setting the pixel source to "SOLID_FILL".
> + *
> + * For information on the plane property, see drm_plane_create_solid_fill_property()
> + *
> + * @r: Red color value of single pixel
> + * @g: Green color value of single pixel
> + * @b: Blue color value of single pixel
> + * @pad: padding, must be zero
> + */
> +struct drm_mode_solid_fill {
> +	__u32 r;
> +	__u32 g;
> +	__u32 b;
> +	__u32 pad;
> +};
> 
> I assume that RGB323232 means unsigned 32-bit UNORM (Vulkan term)
> format. That means 1.0 is 0xffffffff, not 0xff000000. This looks like a
> bug in the test.

Hey Pekka,

Ah, thanks for catching this -- I'll change the blob value to 0xffffffff 
so it matches the 1.0.

While we're talking about the UAPI struct, I'll also add the actual 
drm_mode_solid_fill struct to the IGT drm-uapi instead of the current 
workaround.

> 
> It would be good to test more than one color:
> - 0.0, 0.0, 0.0
> - 1.0, 0.0, 0.0
> - 0.0, 1.0, 0.0
> - 0.0, 0.0, 1.0
> - 1.0, 1.0, 1.0

Sounds good, will change the test to validate these combinations.

> 
> for example. That would get at least the so often used black explicitly
> tested, and verify each channel gets mapped correctly rather than only
> blue.
> 
> It would also be really good to test dim and mid grays, but I assume it
> might be difficult to get CRC to match over various hardware. You'd
> need to use writeback with an error tolerance. (For watching photos for
> example, the background is not usually black but dim gray I believe.)

Got it, we can add this to the list of colors to test.

FWIW, I think as long as we keep the test structure as grabbing a 
reference CRC from an FB commit then comparing that to a CRC from a 
solid fill commit, I'm not expecting a difference in CRC values.

Thanks,

Jessica Zhang

> 
> 
> Thanks,
> pq