[Intel-gfx] [PATCH v2 8/9] drm/i915: expose eu topology to userspace

[Lionel Landwerlin]

On 02/11/17 16:35, Chris Wilson wrote:
> Quoting Lionel Landwerlin (2017-11-02 16:29:48)
>> +/* Query various aspects of the topology of the GPU. Below is a list of the
>> + * currently supported queries. The motivation of this more detailed query
>> + * mechanism is to expose asynmetric properties of the GPU. Starting with CNL,
>> + * slices might have different sizes (for example 3 subslices in slice0 and 2
>> + * subslices in slice1+). This means we cannot rely on PARAM_SUBSLICE_MASK
>> + * anymore.
>> + *
>> + * When using this parameter, getparam value should point to a structure of
>> + * type drm_i915_topology_t. Call this once with query set to the relevant
>> + * information to be queried and data_size set to 0. The kernel will then set
>> + * params and data_size to the expected length of data[]. The should make sure
>> + * memory is allocated to the right length before making a second getparam
>> + * with data_size already set. The kernel will then populate data[]. The
>> + * meaning of params[] elements is described for each query below.
>> + */
>> +#define I915_PARAM_TOPOLOGY                 51
>> +typedef struct drm_i915_topology {
> Oh crumbs. Please join the intel_engine_info_ioctl discussion.

Where is that?

>
> As it stands, lets not introduce multiplexing into an already multiplexed
> getparam ioctl.

But a int* is not enough!

> -Chris
>