1711998 - texture conversion during glTexSubImage with sw-wr on mali-400

Status: NEW

(Core :: Graphics: WebRender, defect)

Description

[Jeff Muizelaar [:jrmuizel]]

I got system symbols working today which produced the following profile:
https://share.firefox.dev/3v73sfB

Notice the mali_convert_texture. I had a look at the leaf function where the time is being spent in ghidra and confirmed that it seems to be swizzling the data.

Comment 1

[Jeff Muizelaar [:jrmuizel]]

Upon further examination it appears that we may be hitting the 'linear-to-block' swizzling code. See here for some related suffering:
https://community.arm.com/developer/tools-software/graphics/f/discussions/6635/mali-400-eglcreateimagekhr-egl_gl_texture_2d_khr-and-updating-textures-with-the-cpu

Comment 2

[Jeff Muizelaar [:jrmuizel]]

Here's the mesa code for doing the conversion: https://github.com/mesa3d/mesa/blob/master/src/panfrost/shared/pan_tiling.c