RE: [Nouveau] [PATCH 1/7] Revert "ACPI / OSI: Add OEM _OSI string to enable dGPU direct output"

From: <Mario.Limonciello@dell.com>
To: <tiwai@suse.de>, <alexdeucher@gmail.com>
Cc: <kherbst@redhat.com>, <nouveau@lists.freedesktop.org>,
	<rafael.j.wysocki@intel.com>, <linux-kernel@vger.kernel.org>,
	<dri-devel@lists.freedesktop.org>, <linux-acpi@vger.kernel.org>,
	<alex.hung@canonical.com>, <bskeggs@redhat.com>,
	<airlied@redhat.com>
Subject: RE: [Nouveau] [PATCH 1/7] Revert "ACPI / OSI: Add OEM _OSI string to enable dGPU direct output"
Date: Thu, 15 Aug 2019 16:19:52 +0000	[thread overview]
Message-ID: <8724585e50004bc8b6f310587555f4a1@AUSX13MPC101.AMER.DELL.COM> (raw)
In-Reply-To: <s5ho90qa34m.wl-tiwai@suse.de>

> -----Original Message-----
> From: Takashi Iwai <tiwai@suse.de>
> Sent: Thursday, August 15, 2019 9:57 AM
> To: Alex Deucher
> Cc: Karol Herbst; Limonciello, Mario; nouveau; Rafael J . Wysocki; LKML; dri-devel;
> Linux ACPI Mailing List; Alex Hung; Ben Skeggs; David Airlie
> Subject: Re: [Nouveau] [PATCH 1/7] Revert "ACPI / OSI: Add OEM _OSI string to
> enable dGPU direct output"
> 
> 
> [EXTERNAL EMAIL]
> 
> On Thu, 15 Aug 2019 16:37:05 +0200,
> Alex Deucher wrote:
> >
> > On Thu, Aug 15, 2019 at 10:25 AM Karol Herbst <kherbst@redhat.com> wrote:
> > >
> > > On Thu, Aug 15, 2019 at 4:20 PM <Mario.Limonciello@dell.com> wrote:
> > > >
> > > > > > There are definitely going to be regressions on machines in the field
> with the
> > > > > > in tree drivers by reverting this.  I think we should have an answer for all
> of
> > > > > those
> > > > > > before this revert is accepted.
> > > > > >
> > > > > > Regarding systems with Intel+NVIDIA, we'll have to work with partners
> to
> > > > > collect
> > > > > > some information on the impact of reverting this.
> > > > > >
> > > > > > When this is used on a system with Intel+AMD the ASL configures AMD
> GPU to
> > > > > use
> > > > > > "Hybrid Graphics" when on Windows and "Power Express" and
> "Switchable
> > > > > Graphics"
> > > > > > when on Linux.
> > > > >
> > > > > and what's exactly the difference between those? And what's the actual
> > > > > issue here?
> > > >
> > > > DP/HDMI is not detected unless plugged in at bootup.  It's due to missing
> HPD
> > > > events.
> > > >
> > >
> > > afaik Lyude was working on fixing all that, at least for some drivers.
> > > If there is something wrong, we still should fix the drivers, not
> > > adding ACPI workarounds.
> > >
> > > Alex: do you know if there are remaining issues regarding that with amdgpu?
> >
> > There was an issue with hpd events not making it to the audio side
> > when things were powered down that was fixed with this patch set:
> > https://patchwork.freedesktop.org/patch/316793/
> > Those patches depended on a bunch of alsa changes as well which may
> > have not been available in the distro used for a particular OEM
> > program.
> 
> FYI, the corresponding commit for ALSA part is destined for 5.4
> kernel:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git/commit/?id=ade
> 49db337a9d44ac5835cfce1ee873549011b27
> 
> BTW, Nouveau should suffer from the same problem.  The patch to add
> the audio component support is found at:
>   https://patchwork.freedesktop.org/patch/319131/
> 
> 

It sounds like 5.3rcX won't be a useful check then.

So am I correct to understand that everything related to the AMD failures
described in this thread should be in linux-next at this point?