[PATCH] radeon: fix pitch alignment for non-power-of-two mipmaps on SI

[Michel Dänzer]

On Don, 2013-09-19 at 18:37 +0200, Marek Olšák wrote:
> On Thu, Sep 19, 2013 at 4:41 PM, Michel Dänzer <michel at daenzer.net> wrote:
> > On Don, 2013-09-19 at 14:33 +0200, Marek Olšák wrote:
> >> This fixes VM protection faults.
> >>
> >> I have a new piglit test which can iterate over all possible widths, heights,
> >> and depths (including NPOT) and tests mipmapping with various texture targets.
> >>
> >> After this is committed, I'll make a new release of libdrm and bump
> >> the libdrm version requirement in Mesa.
> >> ---
> >>  radeon/radeon_surface.c | 14 +++++++++++---
> >>  1 file changed, 11 insertions(+), 3 deletions(-)
> >>
> >> diff --git a/radeon/radeon_surface.c b/radeon/radeon_surface.c
> >> index 1710e34..d5c45c4 100644
> >> --- a/radeon/radeon_surface.c
> >> +++ b/radeon/radeon_surface.c
> >> @@ -1412,7 +1412,11 @@ static void si_surf_minify(struct radeon_surface *surf,
> >>                             uint32_t xalign, uint32_t yalign, uint32_t zalign,
> >>                             uint32_t slice_align, unsigned offset)
> >>  {
> >> -    surflevel->npix_x = mip_minify(surf->npix_x, level);
> >> +    if (level == 0) {
> >> +        surflevel->npix_x = surf->npix_x;
> >> +    } else {
> >> +        surflevel->npix_x = mip_minify(next_power_of_two(surf->npix_x), level);
> >> +    }
> >>      surflevel->npix_y = mip_minify(surf->npix_y, level);
> >>      surflevel->npix_z = mip_minify(surf->npix_z, level);
> >>
> >
> > Shouldn't this be done (only) for nblk_x instead of npix_x?
> 
> First, level[i].npix_x/y/z have misleading names, because they are
> always aligned to a power of two for non-zero mipmap levels, therefore
> Mesa shouldn't use them in place of u_minify, because it's not the
> same thing. In fact, r600g doesn't really use them and even though
> radeonsi does, they are incorrectly used in place of u_minify. It's on
> my TODO list.
> 
> mip_minify is defined as: level ? MAX2(1, next_power_of_two(x >> level)) : x.
> u_minify is defined as: level ? MAX2(1, x >> level) : x.
> 
> Considering that probably nothing in Mesa uses level[i].npix_x/y/z
> correctly, it's not so important what the variables contain.

But it seems like it would be possible to make npix_x/y/z contain the
values their names suggest, by making mip_minify() do the same thing as
u_minify(), and only rounding up to the next power of two for
nblk_x/y/z, wouldn't it?


-- 
Earthling Michel Dänzer           |                   http://www.amd.com
Libre software enthusiast         |          Debian, X and DRI developer