[Intel-gfx] [PATCH 1/2] drm/i915/params: add i915 parameters to debugfs

[Chris Wilson]

Quoting Jani Nikula (2019-12-05 15:43:40)
> Add a debugfs subdirectory i915_params with all the i915 module
> parameters. This is a first step, with lots of boilerplate, and not much
> benefit yet.

Right, creates a mirror [more or less] of /sys/module/i915/parameters. I
probably would have used parameters/ rather than i915_params/, but that
is immaterial.

> 
> This will result in a new device specific debugfs directory at
> /sys/kernel/debug/dri/<N>/i915_params duplicating the module specific
> sysfs directory at /sys/module/i915/parameters/. Going forward, all
> users of the parameters should use the debugfs, with the module
> parameters being phased out.
> 
> Add debugfs permissions to I915_PARAMS_FOR_EACH(). This duplicates the
> mode with module parameter sysfs, but the goal is to make the module
> parameters read-only initial values for device specific parameters.
> 
> 0 mode will bypass debugfs creation. Use it for verbose_state_checks
> which will need special attention in follow-up work.

The patch does what you say, hopefully a local entropy maxima.
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
-Chris