linux-toradex.git/drivers/gpu/drm/drm_vm.c, branch v3.17-rc5

drm: remove dev->vma_count

2013-12-18T01:43:29+00:00

This is just used for a debugfs file, and we can easily reconstruct
this number by just walking the list twice. Which isn't really bad for
a debugfs file anyway.

So let's rip this out.

There's the other issue that the dev->vmalist itself is a bit useless,
since that can be reconstructed with all the memory mapping
information from proc. But remove that is a different topic entirely.

Signed-off-by: Daniel Vetter 
Signed-off-by: Dave Airlie

drm: rip out drm_core_has_AGP

2013-12-18T01:20:04+00:00

Most place actually want to just check for dev->agp (most do, but a
few don't so this fixes a few potential NULL derefs). The only
exception is the agp init code which should check for the AGP driver
feature flag.

Signed-off-by: Daniel Vetter 
Signed-off-by: Dave Airlie

drm/bufs: remove handling of _DRM_GEM mappings

2013-12-18T01:08:42+00:00

Gone with the new gem vma offset manager from David.

We can also ditch the uapi header definition from the enum since
userspace never used this. It ended up in there purely for historical
reasons (for reusing the old drm mmap code essentially), not because
userspace ever needed it.

Cc: David Herrmann 
Reviewed-by: David Herrmann 
Signed-off-by: Daniel Vetter 
Signed-off-by: Dave Airlie

drm: Pass pointers to virt_to_page()

2013-11-06T03:23:20+00:00

Most architectures define virt_to_page() as a macro that casts its
argument such that an argument of type unsigned long will be accepted
without complaint.  However, the proper type is void *, and passing
unsigned long results in a warning on MIPS.

Compile-tested only.

Signed-off-by: Ben Hutchings 
Signed-off-by: Dave Airlie

drm: Do not include page offset in argument to virt_to_page()

2013-11-06T03:23:12+00:00

By definition, the page offset will not affect the result.

Compile-tested only.

Signed-off-by: Ben Hutchings 
Signed-off-by: Dave Airlie

drm: rip out drm_core_has_MTRR checks

2013-08-19T04:11:44+00:00

The new arch_phys_wc_add/del functions do the right thing both with
and without MTRR support in the kernel. So we can drop these
additional checks.

David Herrmann suggest to also kill the DRIVER_USE_MTRR flag since
it's now unused, which spurred me to do a bit a better audit of the
affected drivers. David helped a lot in that. Quoting our mail
discussion:

On Wed, Jul 10, 2013 at 5:41 PM, David Herrmann  wrote:
> On Wed, Jul 10, 2013 at 5:22 PM, Daniel Vetter  wrote:
>> On Wed, Jul 10, 2013 at 3:51 PM, David Herrmann  wrote:
>>>> -#if __OS_HAS_MTRR
>>>> -static inline int drm_core_has_MTRR(struct drm_device *dev)
>>>> -{
>>>> -       return drm_core_check_feature(dev, DRIVER_USE_MTRR);
>>>> -}
>>>> -#else
>>>> -#define drm_core_has_MTRR(dev) (0)
>>>> -#endif
>>>> -
>>>
>>> That was the last user of DRIVER_USE_MTRR (apart from drivers setting
>>> it in .driver_features). Any reason to keep it around?
>>
>> Yeah, I guess we could rip things out. Which will also force me to
>> properly audit drivers for the eventual behaviour change this could
>> entail (in case there's an x86 driver which did not ask for an mtrr,
>> but iirc there isn't).
>
> david@david-mb ~/dev/kernel/linux $ for i in drivers/gpu/drm/* ; do if
> test -d "$i" ; then if ! grep -q USE_MTRR -r $i ; then echo $i ; fi ;
> fi ; done
> drivers/gpu/drm/exynos
> drivers/gpu/drm/gma500
> drivers/gpu/drm/i2c
> drivers/gpu/drm/nouveau
> drivers/gpu/drm/omapdrm
> drivers/gpu/drm/qxl
> drivers/gpu/drm/rcar-du
> drivers/gpu/drm/shmobile
> drivers/gpu/drm/tilcdc
> drivers/gpu/drm/ttm
> drivers/gpu/drm/udl
> drivers/gpu/drm/vmwgfx
> david@david-mb ~/dev/kernel/linux $
>
> So for x86 gma500,nouveau,qxl,udl,vmwgfx don't set DRIVER_USE_MTRR.
> But I cannot tell whether they break if we call arch_phys_wc_add/del,
> anyway. At least nouveau seemed to work here, but it doesn't use AGP
> or drm_bufs, I guess.

Cool, thanks a lot for stitching together the list of drivers to look
at. So for real KMS drivers it's the drives responsibility to add an
mtrr if it needs one. nouvea, radeon, mgag200, i915 and vmwgfx do that
already. Somehow the savage driver also ends up doing that, I have no
idea why.

Note that gma500 as a pure KMS driver doesn't need MTRR setup since
the platforms that it supports all support PAT. So no MTRRs needed to
get wc iomappings.

The mtrr support in the drm core is all for legacy mappings of garts,
framebuffers and registers. All legacy drivers set the USE_MTRR flag,
so we're good there.

All in all I think we can really just ditch this

/endquote

v2: Also kill DRIVER_USE_MTRR as suggested by David Herrmann

v3: Rebase on top of David Herrmann's agp setup/cleanup changes.

Cc: David Herrmann 
Cc: Andy Lutomirski 
Signed-off-by: Daniel Vetter 
Acked-by: Andy Lutomirski 
Reviewed-by: David Herrmann 
Signed-off-by: Dave Airlie

drm_vm: drop explicit VM_IO setting

2013-06-23T20:26:50+00:00

io_remap_pfn_range already sets this internally.

Signed-off-by: Al Viro 
Signed-off-by: Dave Airlie

drm, agpgart: Use pgprot_writecombine for AGP maps and make the MTRR optional

2013-05-31T03:37:31+00:00

I'm not sure I understand the intent of the previous behavior.  mmap
on /dev/agpgart and DRM_AGP maps had no cache flags set, so they
would be fully cacheable.  But the DRM code (most of the time) would
add a write-combining MTRR that would change the effective memory
type to WC.

The new behavior just requests WC explicitly for all AGP maps.

If there is any code out there that expects cacheable access to the
AGP aperture (because the drm driver doesn't request an MTRR or
because it's using /dev/agpgart directly), then it will now end up
with a UC or WC mapping, depending on the architecture and PAT
availability.  But cacheable access to the aperture seems like it's
asking for trouble, because, AIUI, the aperture is an alias of RAM.

Reviewed-by: Daniel Vetter 
Signed-off-by: Andy Lutomirski 
Signed-off-by: Dave Airlie

drm: Update drm_addmap and drm_mmap to use PAT WC instead of MTRRs

2013-05-31T03:37:06+00:00

Previously, DRM_FRAME_BUFFER mappings, as well as DRM_REGISTERS
mappings with DRM_WRITE_COMBINING set, resulted in an unconditional
MTRR being added but the actual mappings being created as UC-.

Now these mappings have the MTRR added only if needed, but they will
be mapped with pgprot_writecombine.

The non-WC DRM_REGISTERS case now uses pgprot_noncached instead of
hardcoding the bit twiddling.

The DRM_AGP case is unchanged for now.

[airlied: fix ppc build]
Reviewed-by: Daniel Vetter 
Signed-off-by: Andy Lutomirski 
Signed-off-by: Dave Airlie

drm: export drm_vm_open_locked

2013-04-26T00:20:00+00:00

The EXYNOS DRM driver uses drm_vm_open_locked in its mmap() function,
and it can be built as a loadable module, which currently fails.
This exports the symbol from the DRM core to avoid

ERROR: "drm_vm_open_locked" [drivers/gpu/drm/exynos/exynosdrm.ko] undefined!

Signed-off-by: Arnd Bergmann 
Cc: Inki Dae 
Cc: Joonyoung Shim 
Cc: Seung-Woo Kim 
Cc: Kyungmin Park 
Signed-off-by: Dave Airlie