ATI 6.12.4 on ultraSparc runs slow

[jean-francois simon]

Hi,
thanks to the people who provided support for big endian architectures, we
are able to run the 6.12.4 ATI driver on a openSolaris sparc platform (T2000
niagara). the graphic is a PCIe card using a e4690. i can see that  the
atombios works fine, it seems, and edid is read OK,...and the gnome desktop
is functional and looks good. plse note that  the configuration uses
shadowfb. and i have configured the ATI driver with

--disable-dri
--disable-exa

BUT, i can see that in the same conditions (same ATI driver version and
configuration, same GPU, shadowfb being used) a linux/x86-64  box runs much
faster:

-x11perf gives much better numbers
-youtube videos runs smoothly, where they run  very slow/choppy on
ultrasparc/solaris.

also i am seeing that the ATI driver is being called on a regular basis
(RADEONBlocHandler() ) while a flash video is being played. this function
along with some cursor related functions (when mouse is moved) seem to be
the only code in the ATI driver that is involved after X is initialized.

so i am assuming that most of the work is done by some X server "painting
code" to the shadowfb in system ram, which is then DMA'ed to the scan out
buffer in the GPU VRAM.

since i see a big difference between solaris/sparc and linux/x86-64, one
idea that comes to mind is that there could some overhead due to the
difference in endianess between the solaris and the linux box.

Assuming my problem is really endian related, is there a way around this?
looking at the code i see some functions  (like
radeon_render.c::RADEONSetupRenderByteswap() ) that seems to be related
..but i have no idea if this applies to my case.

thx a lot
-jf simon
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