[Intel-gfx] [PATCH i-g-t] test/gem_mocs_settings: Testing MOCS register settings

[Peter Antoine]

Response inline.

On Mon, 4 Apr 2016, Chris Wilson wrote:

> On Mon, Apr 04, 2016 at 02:43:08PM +0100, Peter Antoine wrote:
>> +static void run_test(int fd, unsigned mode)
>> +{
>> +	const int gen = intel_gen(intel_get_drm_devid(fd));
>> +	const struct intel_execution_engine *e;
>> +
>> +	igt_require(gen >= 9);
>> +
>> +	test_mocs_values(fd);
>> +
>> +	switch(mode) {
>> +	case NONE:	break;
>> +	case RESET:	igt_force_gpu_reset();	break;
>> +	case SUSPEND:	igt_system_suspend_autoresume(); break;
>> +	case HIBERNATE:	igt_system_hibernate_autoresume(); break;
>> +	};
>> +
>> +	/*
>> +	 * Do render after other engines as older versions of code will
>> +	 * cause the RCS context to program the registers and the test
>> +	 * becomes invalid
>> +	 */
>
> If you defer fd allocation to here, then that is moot, as we can create
> the fd for each test and be sure that the default context is
> uninitialised.

Ok, will wrap each test within an fd of it's own.

>
>> +	for (e = intel_execution_engines; e->name; e++)
>> +		if (e->exec_id != I915_EXEC_DEFAULT &&
>> +		    e->exec_id != I915_EXEC_RENDER &&
>> +		    gem_has_ring(fd, e->exec_id | e->flags))
>> +			test_context_mocs_values(fd, e, true);
>> +
>> +	for (e = intel_execution_engines; e->name; e++)
>> +		if (e->exec_id == I915_EXEC_RENDER &&
>> +		    gem_has_ring(fd, e->exec_id | e->flags)) {
>> +			test_context_mocs_values(fd, e, true);
>> +			test_context_mocs_values(fd, e, false);
>> +		}
>
> As well as checking for creating new contexts after resume, we also need
> to check that the register values are preserved across suspend (i.e.
> that the register state is being saved back into the context image and
> then restored).

Ok, I'll add another test case that does this for the render engine (the 
only one that is effected (at the moment) by context save and resume.

I might as well move the render engine context tests to a new testcase. As 
it is the only engine that uses the context registers.

>
> If we get truly paranoid (and why not?!) then we can create a pair of
> contexts, change the register values in one and verify that the second
> context is unaffected.

Might as well, can add a test case that dirties the RCS context registers 
and see if they are the same after resume and if a new context is created 
afterwards that it has the correct values.

Peter.


> -Chris
>
>

--
    Peter Antoine (Android Graphics Driver Software Engineer)
    ---------------------------------------------------------------------
    Intel Corporation (UK) Limited
    Registered No. 1134945 (England)
    Registered Office: Pipers Way, Swindon SN3 1RJ
    VAT No: 860 2173 47