Expose logical engine instance to user via query engine info IOCTL. This
is required for split-frame workloads as these needs to be placed on
engines in a logically contiguous order. The logical mapping can change
based on fusing. Rather than having user have knowledge of the fusing we
simply just expose the logical mapping with the existing query engine
info IOCTL.
IGT: https://patchwork.freedesktop.org/patch/445637/?series=92854&rev=1
media UMD: https://github.com/intel/media-driver/pull/1252
v2:
(Daniel Vetter)
- Add IGT link, placeholder for media UMD
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211014172005.27155-7-matthew.brost@intel.com
DG1 has support for local memory, which requires the usage of the
lmem placement extension for creating bo's, and memregion queries
to obtain the size. Because of this, those parts of the uapi are
no longer guarded behind FAKE_LMEM.
According to the pull request referenced below, mesa should be mostly
ready for DG1. VK_EXT_memory_budget is not hooked up yet, but we
should definitely just enable the uapi parts by default.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
References: https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11584
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20210812124452.622233-2-maarten.lankhorst@linux.intel.com
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
Treat it the same as the fake local-memory stuff, where it is disabled
for normal kernels, in case some random UMD is tempted to use this. Once
we have all the other bits and pieces in place, like the TTM conversion,
we can turn this on for real.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin@linux.intel.com>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Cc: Dave Airlie <airlied@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Cc: mesa-dev@lists.freedesktop.org
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210429103056.407067-9-matthew.auld@intel.com
Returns the available memory region areas supported by the HW.
v2(Daniel & Jason):
- Add some kernel-doc, including example usage.
- Drop all the extra rsvd
v3(Jason & Tvrtko)
- add back rsvd
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin@linux.intel.com>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Cc: Dave Airlie <airlied@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Cc: mesa-dev@lists.freedesktop.org
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210429103056.407067-3-matthew.auld@intel.com
SSEUs are a GT capability, so track them under gt_info.
Signed-off-by: Venkata Sandeep Dhanalakota <venkata.s.dhanalakota@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200708003952.21831-8-daniele.ceraolospurio@intel.com
Catch up with upstream, in particular to get c1e8d7c6a7 ("mmap locking
API: convert mmap_sem comments").
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.
This code was detected with the help of Coccinelle and, audited and
fixed manually.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200617220331.GA19550@embeddedor
Commit 750e76b4f9 ("drm/i915/gt: Move the [class][inst] lookup for
engines onto the GT") changed the engine query to iterate over uabi
engines but left the buffer size calculation look at the physical engine
count. Difference has no practical consequence but it is nicer to align
both queries.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: 750e76b4f9 ("drm/i915/gt: Move the [class][inst] lookup for engines onto the GT")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191122104115.29610-1-tvrtko.ursulin@linux.intel.com
(cherry picked from commit 9acc99d8f2)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Commit 750e76b4f9 ("drm/i915/gt: Move the [class][inst] lookup for
engines onto the GT") changed the engine query to iterate over uabi
engines but left the buffer size calculation look at the physical engine
count. Difference has no practical consequence but it is nicer to align
both queries.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: 750e76b4f9 ("drm/i915/gt: Move the [class][inst] lookup for engines onto the GT")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191122104115.29610-1-tvrtko.ursulin@linux.intel.com
Listing configurations at the moment is supported only through sysfs.
This might cause issues for applications wanting to list
configurations from a container where sysfs isn't available.
This change adds a way to query the number of configurations and their
content through the i915 query uAPI.
v2: Fix sparse warnings (Lionel)
Add support to query configuration using uuid (Lionel)
v3: Fix some inconsistency in uapi header (Lionel)
Fix unlocking when not locked issue (Lionel)
Add debug messages (Lionel)
v4: Fix missing unlock (Dan)
v5: Drop lock when copying config content to userspace (Chris)
v6: Drop lock when copying config list to userspace (Chris)
Fix deadlock when calling i915_perf_get_oa_config() under
perf.metrics_lock (Lionel)
Add i915_oa_config_get() (Chris)
Link: https://gitlab.freedesktop.org/mesa/mesa/merge_requests/932
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191014201404.22468-2-chris@chris-wilson.co.uk
Add a new SSEU runtime parameter, eu_stride, which is
used to mirror the userspace concept of a range of EUs
per subslice.
This patch simply adds the parameter and updates usage
in the QUERY_TOPOLOGY_INFO handler.
v2: Add GEM_BUG_ON to make sure eu_stride is valid
Signed-off-by: Stuart Summers <stuart.summers@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823160307.180813-5-stuart.summers@intel.com
Add a new parameter, ss_stride, to the runtime info
structure. This is used to mirror the userspace concept
of subslice stride, which is a range of subslices per slice.
This patch simply adds the definition and updates usage
in the QUERY_TOPOLOGY_INFO handler.
v2: Add GEM_BUG_ON to make sure ss_stride is valid
Signed-off-by: Stuart Summers <stuart.summers@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823160307.180813-4-stuart.summers@intel.com
To maintain a fast lookup from a GT centric irq handler, we want the
engine lookup tables on the intel_gt. To avoid having multiple copies of
the same multi-dimension lookup table, move the generic user engine
lookup into an rbtree (for fast and flexible indexing).
v2: Split uabi_instance cf uabi_class
v3: Set uabi_class/uabi_instance after collating all engines to provide a
stable uabi across parallel unordered construction.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> #v2
Link: https://patchwork.freedesktop.org/patch/msgid/20190806124300.24945-2-chris@chris-wilson.co.uk
Currently, the subslice_mask runtime parameter is stored as an
array of subslices per slice. Expand the subslice mask array to
better match what is presented to userspace through the
I915_QUERY_TOPOLOGY_INFO ioctl. The index into this array is
then calculated:
slice * subslice stride + subslice index / 8
v2: fix spacing in set_sseu_info args
use set_sseu_info to initialize sseu data when building
device status in debugfs
rename variables in intel_engine_types.h to avoid checkpatch
warnings
v3: update headers in intel_sseu.h
v4: add const to some sseu_dev_info variables
use sseu->eu_stride for EU stride calculations
v5: address review comments from Tvrtko and Daniele
v6: remove extra space in intel_sseu_get_subslices
return the correct subslice enable in for_each_instdone
add GEM_BUG_ON to ensure user doesn't pass invalid ss_mask size
use printk formatted string for subslice mask
v7: remove string.h header and rebase
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Acked-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Stuart Summers <stuart.summers@intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190524154022.13575-6-stuart.summers@intel.com
Subslice stride and EU stride are calculated multiple times in
i915_query. Move this calculation to a macro to reduce code duplication.
v2: update headers in intel_sseu.h
v3: use GEN_SSEU_STRIDE for stride calculations in intel_sseu.h
apply s/bits/max_entries/ to GEN_SSEU_STRIDE parameter
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Stuart Summers <stuart.summers@intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190524154022.13575-3-stuart.summers@intel.com
Engine discovery query allows userspace to enumerate engines, probe their
configuration features, all without needing to maintain the internal PCI
ID based database.
A new query for the generic i915 query ioctl is added named
DRM_I915_QUERY_ENGINE_INFO, together with accompanying structure
drm_i915_query_engine_info. The address of latter should be passed to the
kernel in the query.data_ptr field, and should be large enough for the
kernel to fill out all known engines as struct drm_i915_engine_info
elements trailing the query.
As with other queries, setting the item query length to zero allows
userspace to query minimum required buffer size.
Enumerated engines have common type mask which can be used to query all
hardware engines, versus engines userspace can submit to using the execbuf
uAPI.
Engines also have capabilities which are per engine class namespace of
bits describing features not present on all engine instances.
v2:
* Fixed HEVC assignment.
* Reorder some fields, rename type to flags, increase width. (Lionel)
* No need to allocate temporary storage if we do it engine by engine.
(Lionel)
v3:
* Describe engine flags and mark mbz fields. (Lionel)
* HEVC only applies to VCS.
v4:
* Squash SFC flag into main patch.
* Tidy some comments.
v5:
* Add uabi_ prefix to engine capabilities. (Chris Wilson)
* Report exact size of engine info array. (Chris Wilson)
* Drop the engine flags. (Joonas Lahtinen)
* Added some more reserved fields.
* Move flags after class/instance.
v6:
* Do not check engine info array was zeroed by userspace but zero the
unused fields for them instead.
v7:
* Simplify length calculation loop. (Lionel Landwerlin)
v8:
* Remove MBZ comments where not applicable.
* Rename ABI flags to match engine class define naming.
* Rename SFC ABI flag to reflect it applies to VCS and VECS.
* SFC is wired to even _logical_ engine instances.
* SFC applies to VCS and VECS.
* HEVC is present on all instances on Gen11. (Tony)
* Simplify length calculation even more. (Chris Wilson)
* Move info_ptr assigment closer to loop for clarity. (Chris Wilson)
* Use vdbox_sfc_access from runtime info.
* Rebase for RUNTIME_INFO.
* Refactor for lower indentation.
* Rename uAPI class/instance to engine_class/instance to avoid C++
keyword.
v9:
* Rebase for s/num_rings/num_engines/ in RUNTIME_INFO.
v10:
* Use new copy_query_item.
v11:
* Consolidate with struct i915_engine_class_instnace.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Dmitry Rogozhkin <dmitry.v.rogozhkin@intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tony Ye <tony.ye@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> # v7
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190522090054.6007-1-tvrtko.ursulin@linux.intel.com
This simplifies adding new query item objects.
v2: Use query_hdr (Tvrtko, Chris).
int instead of u32 in return (Tvrtko)
v3: More naming fixes (Tvrtko)
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190211173251.7131-1-abdiel.janulgue@linux.intel.com
Generally catch up with 5.0-rc1, and specifically get the changes:
96d4f267e4 ("Remove 'type' argument from access_ok() function")
0b2c8f8b6b ("i915: fix missing user_access_end() in page fault exception case")
594cc251fd ("make 'user_access_begin()' do 'access_ok()'")
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We dump the info as an array of u8, so we want to know the length
in number of bytes. Current code is still safe because the
variable we use BITS_PER_TYPE on is a u8.
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181109004013.34394-1-daniele.ceraolospurio@intel.com
In commit 9144d75e22 ("include/linux/bitops.h: introduce BITS_PER_TYPE"),
we made BITS_PER_TYPE available to all and now we can use the macro to
replace some open-coded computation of sizeof(T) * BITS_PER_BYTE.
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180926104707.17410-1-chris@chris-wilson.co.uk
nospec quite reasonably asserts that it will never be used with an index
larger than unsigned long (that being the largest possibly index into an
C array). However, our ubi uses the convention of u64 for any large
integer, running afoul of the assertion on 32b. Reduce our index to an
unsigned long, checking for type overflow first.
drivers/gpu/drm/i915/i915_query.c: In function 'i915_query_ioctl':
include/linux/compiler.h:339:38: error: call to '__compiletime_assert_119' declared with attribute error: BUILD_BUG_ON failed: sizeof(_s) > sizeof(long)
Reported-by: kbuild-all@01.org
Fixes: 84b510e22d ("drm/i915/query: Protect tainted function pointer lookup")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180522121018.15199-1-chris@chris-wilson.co.uk
Smatch identifies i915_query_ioctl() as being a potential victim of
Spectre due to its use of a tainted user index into a function pointer
array. Use array_index_nospec() to defang the user index before using it
to lookup the function pointer.
Fixes: a446ae2c6e ("drm/i915: add query uAPI")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180521210530.26008-1-chris@chris-wilson.co.uk
With the introduction of asymmetric slices in CNL, we cannot rely on
the previous SUBSLICE_MASK getparam to tell userspace what subslices
are available. Here we introduce a more detailed way of querying the
Gen's GPU topology that doesn't aggregate numbers.
This is essential for monitoring parts of the GPU with the OA unit,
because counters need to be normalized to the number of
EUs/subslices/slices. The current aggregated numbers like EU_TOTAL do
not gives us sufficient information.
The Mesa series making use of this API is :
https://patchwork.freedesktop.org/series/38795/
As a bonus we can draw representations of the GPU :
https://imgur.com/a/vuqpa
v2: Rename uapi struct s/_mask/_info/ (Tvrtko)
Report max_slice/subslice/eus_per_subslice rather than strides (Tvrtko)
Add uapi macros to read data from *_info structs (Tvrtko)
v3: Use !!(v & DRM_I915_BIT()) for uapi macros instead of custom shifts (Tvrtko)
v4: factorize query item writting (Tvrtko)
tweak uapi struct/define names (Tvrtko)
v5: Replace ALIGN() macro (Chris)
v6: Updated uapi comments (Tvrtko)
Moved flags != 0 checks into vfuncs (Tvrtko)
v7: Use access_ok() before copying anything, to avoid overflows (Chris)
Switch BUG_ON() to GEM_WARN_ON() (Tvrtko)
v8: Tweak uapi comments style to match the coding style (Lionel)
v9: Fix error in comment about computation of enabled subslice (Tvrtko)
v10: Fix/update comments in uAPI (Sagar)
v11: Drop drm_i915_query_(slice|subslice|eu)_info in favor of a single
drm_i915_query_topology_info (Joonas)
v12: Add subslice_stride/eu_stride in drm_i915_query_topology_info (Joonas)
v13: Fix comment in uAPI (Joonas)
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180306122857.27317-7-lionel.g.landwerlin@intel.com
There are a number of information that are readable from hardware
registers and that we would like to make accessible to userspace. One
particular example is the topology of the execution units (how are
execution units grouped in subslices and slices and also which ones
have been fused off for die recovery).
At the moment the GET_PARAM ioctl covers some basic needs, but
generally is only able to return a single value for each defined
parameter. This is a bit problematic with topology descriptions which
are array/maps of available units.
This change introduces a new ioctl that can deal with requests to fill
structures of potentially variable lengths. The user is expected fill
a query with length fields set at 0 on the first call, the kernel then
sets the length fields to the their expected values. A second call to
the kernel with length fields at their expected values will trigger a
copy of the data to the pointed memory locations.
The scope of this uAPI is only to provide information to userspace,
not to allow configuration of the device.
v2: Simplify dispatcher code iteration (Tvrtko)
Tweak uapi drm_i915_query_item structure (Tvrtko)
v3: Rename pad fields into flags (Chris)
Return error on flags field != 0 (Chris)
Only copy length back to userspace in drm_i915_query_item (Chris)
v4: Use array of functions instead of switch (Chris)
v5: More comments in uapi (Tvrtko)
Return query item errors in length field (All)
v6: Tweak uapi comments style to match the coding style (Lionel)
v7: Add i915_query.h (Joonas)
v8: (Lionel) Change the behavior of the item iterator to report
invalid queries into the query item rather than stopping the
iteration. This enables userspace applications to query newer
items on older kernels and only have failure on the items that are
not supported.
v9: Edit copyright headers (Joonas)
v10: Typos & comments in uapi (Joonas)
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180306122857.27317-6-lionel.g.landwerlin@intel.com
Matthew Brost