[Intel-gfx] [RFC 2/3] drm/i915: Watchdog timeout: Ringbuffer command emission for gen8+

[Tvrtko Ursulin]

On 23/02/2017 21:03, Chris Wilson wrote:
> On Thu, Feb 23, 2017 at 11:44:18AM -0800, Michel Thierry wrote:

[snip]

>> +static int gen8_emit_stop_watchdog(struct drm_i915_gem_request *req)
>> +{
>> +	struct intel_engine_cs *engine = req->engine;
>> +	u32 *cs;
>> +
>> +	cs = intel_ring_begin(req, 4);
>> +	if (IS_ERR(cs))
>> +		return PTR_ERR(cs);
>> +
>> +	*cs++ = MI_LOAD_REGISTER_IMM(1);
>> +	*cs++ = i915_mmio_reg_offset(RING_CNTR(engine->mmio_base));
>> +
>> +	switch (engine->id) {
>> +	default:
>> +		WARN(1, "%s does not support watchdog timeout!\n",
>> +		     engine->name);
>> +	/* default to render engine */
>
> Just
> GEM_BUG_ON(engine->id == BCS);
> if (engine->id == RCS)
> 	*cs++ = GEN8_RCS_WATCHDOG_DISABLE;
> else
> 	*cs++ = GEN8_XCS_WATCHDOG_DISABLE;

I'd go further and store it in the engine eg. "*cs++ = 
engine->watchdog_disable_cmd" or something. I think that's better than 
engines with identity crisis. :)

Regards,

Tvrtko