[igt-dev] [PATCH i-g-t 4/6] i915/gem_engine_topology: Add helpers for checking driver capabilities

[Zbigniew Kempczyński]

On Thu, Mar 10, 2022 at 08:15:27AM +0100, Zbigniew Kempczyński wrote:
> From: Chris Wilson <chris.p.wilson at intel.com>
> 
> If driver is able to report capabilities we want to use them in easy way.
> For example it can support blitter "block_copy" (XY_BLOCK_COPY_BLT
> command) and reports it in sysfs. We add then capabilities helpers to
> read these properties. Helpers allows checking does driver knows
> capability (by checking sysfs "known_capabilities" file) and supports it
> (by checking sysfs "capabilities" file). Dedicated helper was added to
> verify "block_copy" capability.
> 
> Signed-off-by: Chris Wilson <chris.p.wilson at intel.com>
> Signed-off-by: Apoorva Singh <apoorva1.singh at intel.com>
> Cc: Zbigniew Kempczyński <zbigniew.kempczynski at intel.com>
> Cc: Arjun Melkaveri <arjun.melkaveri at intel.com>

Looks good for me.

Reviewed-by: Zbigniew Kempczyński <zbigniew.kempczynski at intel.com>

--
Zbigniew

> ---
>  lib/i915/gem_engine_topology.c | 39 ++++++++++++++++++++++++++++++++++
>  lib/i915/gem_engine_topology.h |  5 +++++
>  2 files changed, 44 insertions(+)
> 
> diff --git a/lib/i915/gem_engine_topology.c b/lib/i915/gem_engine_topology.c
> index bd12d0bc98..ca3333c252 100644
> --- a/lib/i915/gem_engine_topology.c
> +++ b/lib/i915/gem_engine_topology.c
> @@ -534,6 +534,45 @@ void gem_engine_properties_restore(int fd, const struct gem_engine_properties *s
>  	}
>  }
>  
> +static bool
> +__gem_engine_has_capability(int i915, const char *engine,
> +			    const char *attr, const char *cap)
> +{
> +	char buf[4096] = {};
> +	FILE *file;
> +
> +	file = __open_attr(igt_sysfs_open(i915), "r",
> +			   "engine", engine, attr, NULL);
> +	if (!file)
> +		return NULL;
> +
> +	fread(buf, 1, sizeof(buf) - 1, file);
> +	fclose(file);
> +
> +	return strstr(buf, cap);
> +}
> +
> +bool gem_engine_has_capability(int i915, const char *engine, const char *cap)
> +{
> +	return __gem_engine_has_capability(i915, engine, "capabilities", cap);
> +}
> +
> +bool gem_engine_has_known_capability(int i915, const char *engine, const char *cap)
> +{
> +	return __gem_engine_has_capability(i915, engine, "known_capabilities", cap);
> +}
> +
> +bool gem_engine_can_block_copy(int i915, const struct intel_execution_engine2 *engine)
> +{
> +	if (engine->class != I915_ENGINE_CLASS_COPY)
> +		return false;
> +
> +	if (!gem_engine_has_known_capability(i915, engine->name, "block_copy"))
> +		return intel_gen(intel_get_drm_devid(i915)) >= 12;
> +
> +	return gem_engine_has_capability(i915, engine->name, "block_copy");
> +}
> +
>  uint32_t gem_engine_mmio_base(int i915, const char *engine)
>  {
>  	unsigned int mmio = 0;
> diff --git a/lib/i915/gem_engine_topology.h b/lib/i915/gem_engine_topology.h
> index b413aa8aba..987f2bf944 100644
> --- a/lib/i915/gem_engine_topology.h
> +++ b/lib/i915/gem_engine_topology.h
> @@ -133,6 +133,11 @@ int gem_engine_property_printf(int i915, const char *engine, const char *attr,
>  
>  uint32_t gem_engine_mmio_base(int i915, const char *engine);
>  
> +bool gem_engine_has_capability(int i915, const char *engine, const char *cap);
> +bool gem_engine_has_known_capability(int i915, const char *engine, const char *cap);
> +
> +bool gem_engine_can_block_copy(int i915, const struct intel_execution_engine2 *engine);
> +
>  void dyn_sysfs_engines(int i915, int engines, const char *file,
>  		       void (*test)(int i915, int engine));
>  
> -- 
> 2.32.0
>