LoongArch: Add writecombine support for drm

LoongArch maintains cache coherency in hardware, but its WUC attribute
(Weak-ordered UnCached, which is similar to WC) is out of the scope of
cache cohere

LoongArch: Add writecombine support for drm

LoongArch maintains cache coherency in hardware, but its WUC attribute
(Weak-ordered UnCached, which is similar to WC) is out of the scope of
cache coherency machanism. This means WUC can only used for write-only
memory regions.

Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

show more ...

dma-buf-map: Rename to iosys-map

Rename struct dma_buf_map to struct iosys_map and corresponding APIs.
Over time dma-buf-map grew up to more functionality than the one used by
dma-buf: in fact it's

dma-buf-map: Rename to iosys-map

Rename struct dma_buf_map to struct iosys_map and corresponding APIs.
Over time dma-buf-map grew up to more functionality than the one used by
dma-buf: in fact it's just a shim layer to abstract system memory, that
can be accessed via regular load and store, from IO memory that needs to
be acessed via arch helpers.

The idea is to extend this API so it can fulfill other needs, internal
to a single driver. Example: in the i915 driver it's desired to share
the implementation for integrated graphics, which uses mostly system
memory, with discrete graphics, which may need to access IO memory.

The conversion was mostly done with the following semantic patch:

@r1@
@@
- struct dma_buf_map
+ struct iosys_map

@r2@
@@
(
- DMA_BUF_MAP_INIT_VADDR
+ IOSYS_MAP_INIT_VADDR
|
- dma_buf_map_set_vaddr
+ iosys_map_set_vaddr
|
- dma_buf_map_set_vaddr_iomem
+ iosys_map_set_vaddr_iomem
|
- dma_buf_map_is_equal
+ iosys_map_is_equal
|
- dma_buf_map_is_null
+ iosys_map_is_null
|
- dma_buf_map_is_set
+ iosys_map_is_set
|
- dma_buf_map_clear
+ iosys_map_clear
|
- dma_buf_map_memcpy_to
+ iosys_map_memcpy_to
|
- dma_buf_map_incr
+ iosys_map_incr
)

@@
@@
- #include <linux/dma-buf-map.h>
+ #include <linux/iosys-map.h>

Then some files had their includes adjusted and some comments were
update to remove mentions to dma-buf-map.

Since this is not specific to dma-buf anymore, move the documentation to
the "Bus-Independent Device Accesses" section.

v2:
- Squash patches

v3:
- Fix wrong removal of dma-buf.h from MAINTAINERS
- Move documentation from dma-buf.rst to device-io.rst

v4:
- Change documentation title and level

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220204170541.829227-1-lucas.demarchi@intel.com

show more ...

drm: Add a prefetching memcpy_from_wc

Reading out of write-combining mapped memory is typically very slow
since the CPU doesn't prefetch. However some archs have special
instructions to do this.

So

drm: Add a prefetching memcpy_from_wc

Reading out of write-combining mapped memory is typically very slow
since the CPU doesn't prefetch. However some archs have special
instructions to do this.

So add a best-effort memcpy_from_wc taking dma-buf-map pointer
arguments that attempts to use a fast prefetching memcpy and
otherwise falls back to ordinary memcopies, taking the iomem tagging
into account.

The code is largely copied from i915_memcpy_from_wc.

Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Christian König <christian.koenig@amd.com>
Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://lore.kernel.org/r/20210602083818.241793-5-thomas.hellstrom@linux.intel.com
Link: https://patchwork.freedesktop.org/patch/msgid/20210602083818.241793-5-thomas.hellstrom@linux.intel.com

show more ...

MIPS: Loongson64: Rename CPU TYPES

CPU_LOONGSON2 -> CPU_LOONGSON2EF
CPU_LOONGSON3 -> CPU_LOONGSON64

As newer loongson-2 products (2G/2H/2K1000) can share kernel
implementation with loongson-3 while

MIPS: Loongson64: Rename CPU TYPES

CPU_LOONGSON2 -> CPU_LOONGSON2EF
CPU_LOONGSON3 -> CPU_LOONGSON64

As newer loongson-2 products (2G/2H/2K1000) can share kernel
implementation with loongson-3 while 2E/2F are less similar with
other LOONGSON64 products.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: chenhc@lemote.com
Cc: paul.burton@mips.com

show more ...

drm: change func to better detect wether swiotlb is needed

This commit fixes DRM failures on Xen PV systems that were introduced in
v4.17 by the following commits:

82626363 drm: add func to get max

drm: change func to better detect wether swiotlb is needed

This commit fixes DRM failures on Xen PV systems that were introduced in
v4.17 by the following commits:

82626363 drm: add func to get max iomem address v2
fd5fd480 drm/amdgpu: only enable swiotlb alloc when need v2
1bc3d3cc drm/radeon: only enable swiotlb path when need v2

The introduction of ->need_swiotlb to the ttm_dma_populate() conditionals
in the radeon and amdgpu device drivers causes Gnome to immediately crash
on Xen PV systems, returning the user to the login screen. The following
kernel errors get logged:

[ 28.554259] radeon_dp_aux_transfer_native: 200 callbacks suppressed
[ 31.219821] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes)
[ 31.220030] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14)
[ 31.226109] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes)
[ 31.226300] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14)
[ 31.300734] gnome-shell[1935]: segfault at 88 ip 00007f39151cd904 sp 00007ffc97611ad8 error 4 in libmutter-cogl.so[7f3915178000+aa000]
[ 31.300745] Code: 5f c3 0f 1f 40 00 48 8b 47 78 48 8b 40 40 ff e0 66 0f 1f 44 00 00 48 8b 47 78 48 8b 40 48 ff e0 66 0f 1f 44 00 00 48 8b 47 78 <48> 8b 80 88 00 00 00 ff e0 0f 1f 00 48 8b 47 78 48 8b 40 68 ff e0
[ 38.193302] radeon_dp_aux_transfer_native: 116 callbacks suppressed
[ 40.009317] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes)
[ 40.009488] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14)
[ 40.015114] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes)
[ 40.015297] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14)
[ 40.028302] gnome-shell[2431]: segfault at 2dadf40 ip 0000000002dadf40 sp 00007ffcd24ea5f8 error 15
[ 40.028306] Code: 20 6e 31 00 00 00 00 00 00 00 00 37 e3 3d 2d 7f 00 00 80 f4 e6 3d 2d 7f 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <00> 00 00 00 00 00 00 00 c1 00 00 00 00 00 00 00 80 e1 d2 03 00 00

This commit renames drm_get_max_iomem() to drm_need_swiotlb(), adds a
xen_pv_domain() check to it, and moves the bit shifting comparison that
always follows its usage into the function (simplifying the drm driver
code).

Signed-off-by: Michael D Labriola <michael.d.labriola@gmail.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/286987/

show more ...

drm: disable uncached DMA optimization for ARM and arm64

The DRM driver stack is designed to work with cache coherent devices
only, but permits an optimization to be enabled in some cases, where
for

drm: disable uncached DMA optimization for ARM and arm64

The DRM driver stack is designed to work with cache coherent devices
only, but permits an optimization to be enabled in some cases, where
for some buffers, both the CPU and the GPU use uncached mappings,
removing the need for DMA snooping and allocation in the CPU caches.

The use of uncached GPU mappings relies on the correct implementation
of the PCIe NoSnoop TLP attribute by the platform, otherwise the GPU
will use cached mappings nonetheless. On x86 platforms, this does not
seem to matter, as uncached CPU mappings will snoop the caches in any
case. However, on ARM and arm64, enabling this optimization on a
platform where NoSnoop is ignored results in loss of coherency, which
breaks correct operation of the device. Since we have no way of
detecting whether NoSnoop works or not, just disable this
optimization entirely for ARM and arm64.

Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: David Zhou <David1.Zhou@amd.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Junwei Zhang <Jerry.Zhang@amd.com>
Cc: Michel Daenzer <michel.daenzer@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: amd-gfx list <amd-gfx@lists.freedesktop.org>
Cc: dri-devel <dri-devel@lists.freedesktop.org>
Reported-by: Carsten Haitzler <Carsten.Haitzler@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.kernel.org/patch/10778815/
Signed-off-by: Christian König <christian.koenig@amd.com>

show more ...

drm: add func to get max iomem address v2

it will be used to check if the driver needs swiotlb
v2: Don't use inline, instead, move function to drm_memory.c (Michel Daenzer <michel@daenzer.net>)

Sig

drm: add func to get max iomem address v2

it will be used to check if the driver needs swiotlb
v2: Don't use inline, instead, move function to drm_memory.c (Michel Daenzer <michel@daenzer.net>)

Signed-off-by: Chunming Zhou <david1.zhou@amd.com>
Reviewed-by: Monk Liu <monk.liu@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180209024410.1469-1-david1.zhou@amd.com

show more ...

drm: Move drm_clflush prototypes to drm_cache header file

Continue to clean up drmP.h by moving the cache flushing functions into
it's own header file.

Compile-tested only

Signed-off-by: Gabriel K

drm: Move drm_clflush prototypes to drm_cache header file

Continue to clean up drmP.h by moving the cache flushing functions into
it's own header file.

Compile-tested only

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170109215649.6860-2-krisman@collabora.co.uk

show more ...

drm: Loongson-3 doesn't fully support wc memory

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: stable@vger.kernel.org
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Ai

drm: Loongson-3 doesn't fully support wc memory

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: stable@vger.kernel.org
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

show more ...

drm: add helper to check for wc memory support

Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.

drm: add helper to check for wc memory support

Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

show more ...

drm/ttm: consolidate cache flushing code in one place.

This merges the TTM and drm cache flushing into one file in the
drm core.

Signed-off-by: Dave Airlie <airlied@redhat.com>

MIPS: Loongson64: Rename CPU TYPES

CPU_LOONGSON2 -> CPU_LOONGSON2EF
CPU_LOONGSON3 -> CPU_LOONGSON64

As newer loongson-2 products (2G/2H/2K1000) can share kernel
implementati

MIPS: Loongson64: Rename CPU TYPES

CPU_LOONGSON2 -> CPU_LOONGSON2EF
CPU_LOONGSON3 -> CPU_LOONGSON64

As newer loongson-2 products (2G/2H/2K1000) can share kernel
implementation with loongson-3 while 2E/2F are less similar with
other LOONGSON64 products.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: chenhc@lemote.com
Cc: paul.burton@mips.com

show more ...

drm: change func to better detect wether swiotlb is needed

This commit fixes DRM failures on Xen PV systems that were introduced in
v4.17 by the following commits:

82626363 drm:

drm: change func to better detect wether swiotlb is needed

This commit fixes DRM failures on Xen PV systems that were introduced in
v4.17 by the following commits:

82626363 drm: add func to get max iomem address v2
fd5fd480 drm/amdgpu: only enable swiotlb alloc when need v2
1bc3d3cc drm/radeon: only enable swiotlb path when need v2

The introduction of ->need_swiotlb to the ttm_dma_populate() conditionals
in the radeon and amdgpu device drivers causes Gnome to immediately crash
on Xen PV systems, returning the user to the login screen. The following
kernel errors get logged:

[ 28.554259] radeon_dp_aux_transfer_native: 200 callbacks suppressed
[ 31.219821] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes)
[ 31.220030] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14)
[ 31.226109] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes)
[ 31.226300] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14)
[ 31.300734] gnome-shell[1935]: segfault at 88 ip 00007f39151cd904 sp 00007ffc97611ad8 error 4 in libmutter-cogl.so[7f3915178000+aa000]
[ 31.300745] Code: 5f c3 0f 1f 40 00 48 8b 47 78 48 8b 40 40 ff e0 66 0f 1f 44 00 00 48 8b 47 78 48 8b 40 48 ff e0 66 0f 1f 44 00 00 48 8b 47 78 <48> 8b 80 88 00 00 00 ff e0 0f 1f 00 48 8b 47 78 48 8b 40 68 ff e0
[ 38.193302] radeon_dp_aux_transfer_native: 116 callbacks suppressed
[ 40.009317] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes)
[ 40.009488] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14)
[ 40.015114] radeon 0000:01:00.0: swiotlb buffer is full (sz: 2097152 bytes)
[ 40.015297] [drm:radeon_gem_object_create [radeon]] *ERROR* Failed to allocate GEM object (16384000, 2, 4096, -14)
[ 40.028302] gnome-shell[2431]: segfault at 2dadf40 ip 0000000002dadf40 sp 00007ffcd24ea5f8 error 15
[ 40.028306] Code: 20 6e 31 00 00 00 00 00 00 00 00 37 e3 3d 2d 7f 00 00 80 f4 e6 3d 2d 7f 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <00> 00 00 00 00 00 00 00 c1 00 00 00 00 00 00 00 80 e1 d2 03 00 00

This commit renames drm_get_max_iomem() to drm_need_swiotlb(), adds a
xen_pv_domain() check to it, and moves the bit shifting comparison that
always follows its usage into the function (simplifying the drm driver
code).

Signed-off-by: Michael D Labriola <michael.d.labriola@gmail.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/286987/

show more ...

drm: disable uncached DMA optimization for ARM and arm64

The DRM driver stack is designed to work with cache coherent devices
only, but permits an optimization to be enabled in some case

drm: disable uncached DMA optimization for ARM and arm64

The DRM driver stack is designed to work with cache coherent devices
only, but permits an optimization to be enabled in some cases, where
for some buffers, both the CPU and the GPU use uncached mappings,
removing the need for DMA snooping and allocation in the CPU caches.

The use of uncached GPU mappings relies on the correct implementation
of the PCIe NoSnoop TLP attribute by the platform, otherwise the GPU
will use cached mappings nonetheless. On x86 platforms, this does not
seem to matter, as uncached CPU mappings will snoop the caches in any
case. However, on ARM and arm64, enabling this optimization on a
platform where NoSnoop is ignored results in loss of coherency, which
breaks correct operation of the device. Since we have no way of
detecting whether NoSnoop works or not, just disable this
optimization entirely for ARM and arm64.

Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: David Zhou <David1.Zhou@amd.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Junwei Zhang <Jerry.Zhang@amd.com>
Cc: Michel Daenzer <michel.daenzer@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: amd-gfx list <amd-gfx@lists.freedesktop.org>
Cc: dri-devel <dri-devel@lists.freedesktop.org>
Reported-by: Carsten Haitzler <Carsten.Haitzler@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.kernel.org/patch/10778815/
Signed-off-by: Christian König <christian.koenig@amd.com>

show more ...

drm: add func to get max iomem address v2

it will be used to check if the driver needs swiotlb
v2: Don't use inline, instead, move function to drm_memory.c (Michel Daenzer <michel@daenze

drm: add func to get max iomem address v2

it will be used to check if the driver needs swiotlb
v2: Don't use inline, instead, move function to drm_memory.c (Michel Daenzer <michel@daenzer.net>)

Signed-off-by: Chunming Zhou <david1.zhou@amd.com>
Reviewed-by: Monk Liu <monk.liu@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180209024410.1469-1-david1.zhou@amd.com

show more ...

drm: Move drm_clflush prototypes to drm_cache header file

Continue to clean up drmP.h by moving the cache flushing functions into
it's own header file.

Compile-tested only

drm: Move drm_clflush prototypes to drm_cache header file

Continue to clean up drmP.h by moving the cache flushing functions into
it's own header file.

Compile-tested only

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170109215649.6860-2-krisman@collabora.co.uk

show more ...

drm: Loongson-3 doesn't fully support wc memory

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: stable@vger.kernel.org
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Si

drm: Loongson-3 doesn't fully support wc memory

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: stable@vger.kernel.org
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

show more ...

drm: add helper to check for wc memory support

Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Dave Airlie

drm: add helper to check for wc memory support

Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

show more ...

drm/ttm: consolidate cache flushing code in one place.

This merges the TTM and drm cache flushing into one file in the
drm core.

Signed-off-by: Dave Airlie <airlied@redhat.com>