On Tue, Feb 24, 2015 at 10:20:17AM +0000, Daniel, Thomas wrote: > > -----Original Message----- > > From: Daniel Vetter [mailto:daniel.vetter@xxxxxxxx] On Behalf Of Daniel Vetter > > Sent: Monday, February 23, 2015 11:28 PM > > To: Gordon, David S > > Cc: Daniel, Thomas; intel-gfx@xxxxxxxxxxxxxxxxxxxxx > > Subject: Re: [PATCH] drm/i915: Shift driver's HWSP usage out of > > reserved range > > > > On Thu, Feb 19, 2015 at 02:58:48PM +0000, Dave Gordon wrote: > > > On 18/02/15 11:48, Thomas Daniel wrote: > > > > As of Gen6, the general purpose area of the hardware status page has shrunk > > and > > > > now begins at dword 0x30. i915 driver uses dword 0x20 to store the seqno > > which > > > > is now reserved. So shift our HWSP dwords up into the general purpose > > range > > > > before this bites us. > > > > It would be really interesting to know what exactly the hw does with > > offsets below 0x30 ... it might explain some of the bugs we've seen. Can > > you please digg that out so that I can amend the commit message? > > All documentation I've seen just says "Reserved" for current hardware > including SKL so we can't rely on any particular usage. That's why I > just put "Reserved" for these dwords in the comment. Thanks for the clarification, I've ammended the commit message. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
