[igt-dev] [PATCH i-g-t 2/3] lib/igt_fb: Use render copy/blit for tiled formats on platforms w/o HW detiling

[Juha-Pekka Heikkila]

On 21.1.2020 18.35, Imre Deak wrote:
> On Tue, Jan 21, 2020 at 06:19:30PM +0200, Juha-Pekka Heikkila wrote:
>> On 21.1.2020 0.03, Imre Deak wrote:
>>> On platforms without HW detiling use render copy or blitting to convert
>>> between a tiled and a linear framebuffer.
>>>
>>> Signed-off-by: Imre Deak <imre.deak at intel.com>
>>> ---
>>>    lib/igt_fb.c | 16 +++++++++++++---
>>>    1 file changed, 13 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/lib/igt_fb.c b/lib/igt_fb.c
>>> index c81b9de8..b5b1750e 100644
>>> --- a/lib/igt_fb.c
>>> +++ b/lib/igt_fb.c
>>> @@ -1975,17 +1975,27 @@ static bool blitter_ok(const struct igt_fb *fb)
>>>    	return true;
>>>    }
>>> +static bool hw_can_detile(const struct igt_fb *fb)
>>> +{
>>> +	if (fb->modifier == DRM_FORMAT_MOD_NONE)
>>> +		return true;
>>> +
>>> +	if (!gem_has_legacy_hw_tiling(fb->fd))
>>> +		return false;
>>> +
>>> +	return fb->modifier != I915_FORMAT_MOD_Yf_TILED;
>>
>> Should above line depend on gen? Like
>> return (gen < 12 || fb->modifier != I915_FORMAT_MOD_Yf_TILED); ?
> 
> AFAIK no platform can detile the Yf format (only X or Y), but this
> shouldn't change the logic in any case, except for
> !gem_has_legacy_hw_tiling().
> 

You are right.

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila at gmail.com>

>>
>>> +}
>>> +
>>>    static bool use_enginecopy(const struct igt_fb *fb)
>>>    {
>>>    	return is_ccs_modifier(fb->modifier) ||
>>> -		(fb->modifier == I915_FORMAT_MOD_Yf_TILED &&
>>> -		 !blitter_ok(fb));
>>> +		(!hw_can_detile(fb) && !blitter_ok(fb));
>>>    }
>>>    static bool use_blitter(const struct igt_fb *fb)
>>>    {
>>>    	return (fb->modifier == I915_FORMAT_MOD_Y_TILED ||
>>> -		fb->modifier == I915_FORMAT_MOD_Yf_TILED) &&
>>> +		!hw_can_detile(fb)) &&
>>>    		blitter_ok(fb);
>>>    }
>>>
>>