On Wed, Apr 02, 2014 at 04:28:06PM +0100, Chris Wilson wrote: > On Wed, Apr 02, 2014 at 11:14:58AM -0300, Paulo Zanoni wrote: > > 2014-04-02 8:27 GMT-03:00 Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>: > > > On Wed, Apr 02, 2014 at 12:23:51PM +0100, Chris Wilson wrote: > > >> On Wed, Apr 02, 2014 at 12:21:45PM +0100, Damien Lespiau wrote: > > >> > On Tue, Apr 01, 2014 at 03:37:27PM -0300, Paulo Zanoni wrote: > > >> > > From: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx> > > >> > > > > >> > > We should only enable interrupts at postinstall. > > >> > > > > >> > > And now on ILK/SNB/IVB/HSW the irq_preinstall and irq_postinstall > > >> > > functions leave the hardware in the same state. > > >> > > > > >> > > Signed-off-by: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx> > > >> > > > >> > Orthogonal note to this patch, I'm wondering why we enable any interrupt > > >> > reporting in the HW status page, I don't see anywhere we read that > > >> > information back? Any idea? > > >> > > >> Back in the SNB days, interrupts broke without this piece of magic. > > > > > > To be more precise, iirc, it was a step towards getting coherent > > > breadcrumb writes into the HWS. As it turns out, there were more steps > > > required. Considering that it can now probably be dropped again? Any > > > takers? > > > > I noticed the HWSTAM code looks weird, but I don't really know much > > about why it's there, so I decided to not add any regressions. I wrote > > this patch a long time ago, and gave up on upstreaming it, but in case > > anybody wants, I can send it to the list: > > http://cgit.freedesktop.org/~pzanoni/linux/commit/?h=c8-wip&id=7ebe245a2c55379ddc7b36f1fb440215c23f1570 > > . Look at the commit message, it may be an interesting starting point > > if anybody wants to dig on the issue... > > Yup, that is very interesting. That may be the minimal piece of HWSTAM > magic we need, and be an interim step to removing HWSTAM entirely. Would you mind resending: - a patch with Chris' comment above, that's alone is useful for the next guy looking at the code, - a patch with the change (Maybe reusing GT_RENDER_USER_INTERRUPT as HWSTAM uses the same definitions as the other interrupts registers)? I'm sure we can get some reviews on the first, hopefully some testing on the second. -- Damien _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
