[Intel-gfx] [RFC 00/22] Gen7 batch buffer command parser

[Chris Wilson]

On Wed, Feb 05, 2014 at 10:18:44AM -0800, Volkin, Bradley D wrote:
> On Wed, Feb 05, 2014 at 02:28:29AM -0800, Chris Wilson wrote:
> > On Tue, Nov 26, 2013 at 08:51:17AM -0800, bradley.d.volkin at intel.com wrote:
> > > From: Brad Volkin <bradley.d.volkin at intel.com>
> > > 
> > > Certain OpenGL features (e.g. transform feedback, performance monitoring)
> > > require userspace code to submit batches containing commands such as
> > > MI_LOAD_REGISTER_IMM to access various registers. Unfortunately, some
> > > generations of the hardware will noop these commands in "unsecure" batches
> > > (which includes all userspace batches submitted via i915) even though the
> > > commands may be safe and represent the intended programming model of the device.
> > > 
> > > This series introduces a software command parser similar in operation to the
> > > command parsing done in hardware for unsecure batches. However, the software
> > > parser allows some operations that would be noop'd by hardware, if the parser
> > > determines the operation is safe, and submits the batch as "secure" to prevent
> > > hardware parsing. Currently the series implements this on IVB and HSW.
> > 
> > Just one more question... Do you have a branch for people to test?
> 
> Not at the moment. And as mentioned in the v2 cover letter, it's actually not
> particularly testable (or mergeable for that matter) right now because of a
> regression in secure dispatch on nightly.

At this moment, I just want to be sure that the fixed dispatch overhead has
been minimised.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre