From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH v2] drm/i915: move power domain init earlier during system resume Date: Thu, 3 Apr 2014 23:06:13 +0200 Message-ID: <20140403210613.GM7225@phenom.ffwll.local> References: <1395396631-12243-1-git-send-email-imre.deak@intel.com> <1396371322-13752-1-git-send-email-imre.deak@intel.com> <20140401174827.GO22327@phenom.ffwll.local> <1396378243.2488.10.camel@ideak-mobl> <20140403152310.GH7225@phenom.ffwll.local> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Takashi Iwai Cc: "alsa-devel@alsa-project.org" , intel-gfx List-Id: alsa-devel@alsa-project.org On Thu, Apr 03, 2014 at 05:31:17PM +0200, Takashi Iwai wrote: > At Thu, 3 Apr 2014 17:23:10 +0200, > Daniel Vetter wrote: > > > > On Wed, Apr 02, 2014 at 02:59:54PM +0200, Takashi Iwai wrote: > > > At Tue, 1 Apr 2014 22:26:20 +0200, > > > Daniel Vetter wrote: > > > > > > > > On Tue, Apr 01, 2014 at 09:50:43PM +0300, Imre Deak wrote: > > > > > On Tue, 2014-04-01 at 19:48 +0200, Daniel Vetter wrote: > > > > > > On Tue, Apr 01, 2014 at 07:55:22PM +0300, Imre Deak wrote: > > > > > > > During resume the intel hda audio driver depends on the i915 driver > > > > > > > reinitializing the audio power domain. Since the order of calling the > > > > > > > i915 resume handler wrt. that of the audio driver is not guaranteed, > > > > > > > move the power domain reinitialization step to the resume_early > > > > > > > handler. This is guaranteed to run before the resume handler of any > > > > > > > other driver. > > > > > > > > > > > > > > The power domain initialization in turn requires us to enable the i915 > > > > > > > pci device first, so move that part earlier too. > > > > > > > > > > > > > > Accordingly disabling of the i915 pci device should happen after the > > > > > > > audio suspend handler ran. So move the disabling later from the i915 > > > > > > > resume handler to the resume_late handler. > > > > > > > > > > > > > > v2: > > > > > > > - move intel_uncore_sanitize/early_sanitize earlier too, so they don't > > > > > > > get reordered wrt. intel_power_domains_init_hw() > > > > > > > > > > > > > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76152 > > > > > > > Signed-off-by: Imre Deak > > > > > > > > > > > > So this is kinda why we should have gone with something proper, like a new > > > > > > hdmi sink platform device created by i915 and registered as a driver by > > > > > > snd-hda. Then the power domains stuff in the device core should take care > > > > > > of these kinds of ordering issues. Or at least snd-hda can tell it that it > > > > > > needs to wait for the hdmi-sink power domain to go on first before it can > > > > > > resume, I'm not really fluent on the details here. > > > > > > > > > > > > And having a hdmi sink bus would allow us to throw all kinds of crap into > > > > > > a clearly-defined interface, e.g. eld handling, hdcp synchronization, hpd > > > > > > forwarding and all the other fun stuff. > > > > > > > > > > > > So not sure what I should do with this here now. > > > > > > > > > > Right, I'm not too happy about this solution either, so if anything it > > > > > could be considered only a stop-gap fix. What you suggest seems to be a > > > > > cleaner way but it'd require more time to investigate/implement at least > > > > > on my part (but I'm ok to put it on my TODO list). > > > > > > > > We'd definitely need to discuss this with Takashi Iwai, since it would > > > > only really be useful if it's good enough to solve the general pile of > > > > sound/gfx coordination issues we have with hdmi. Adding him and alsa-dev. > > > > > > Yep, having a dedicated channel (hdmi sink bus or whatever) would be > > > definitely a better way to go. OTOH, I agree that Imre's patch is > > > needed for the upcoming kernel. The former implementation can't be > > > finished so quickly for 3.15. > > > > > > I thought Mengdong started looking at (or working on) this, but > > > haven't heard the progress yet. Mengdong, any news? > > > > Ok, I'll splash a big honky FIXME over this so we don't forget ;-) Is the > > patch otherwise ok with you Takashi? > > Yes, it's touching only i915 stuff in anyway ;) > Feel free to take my ack: > Reviewed-by: Takashi Iwai Ok, I've pulled this into 3.15-fixes and added some big comments to the newly-added late/early hooks. I'll try to poke Mengmeng about the status of the hdmi infrastructure work. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch