Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Tue, 25 Jul 2023 14:19:21 +0200
Message-ID: <87351ctc8m.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Cc:     Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        =?ISO-8859-1?Q?P=E9ter?= Ujfalusi 
        <peter.ujfalusi@linux.intel.com>, alsa-devel@alsa-project.org,
        sound-open-firmware@alsa-project.org, linux-kernel@vger.kernel.org,
        Jaroslav Kysela <perex@perex.cz>,
        Takashi Iwai <tiwai@suse.com>,
        Cezary Rojewski <cezary.rojewski@intel.com>,
        Liam Girdwood <liam.r.girdwood@linux.intel.com>,
        Bard Liao <yung-chuan.liao@linux.intel.com>,
        Ranjani Sridharan <ranjani.sridharan@linux.intel.com>,
        Kai Vehmanen <kai.vehmanen@linux.intel.com>,
        Mark Brown <broonie@kernel.org>,
        Daniel Baluta <daniel.baluta@nxp.com>
Subject: Re: [PATCH v2 2/9] ALSA: hda/i915: Allow override of gpu binding.
In-Reply-To: <b0037097-b917-9069-7d8f-07e0317d6b9f@linux.intel.com>
References: <20230719164141.228073-1-maarten.lankhorst@linux.intel.com>
        <20230719164141.228073-3-maarten.lankhorst@linux.intel.com>
        <9b285ede-eaeb-40a2-086d-30cf74185784@linux.intel.com>
        <d75c1902-b715-4a33-1965-ec06d625e3ac@linux.intel.com>
        <932c4293-375f-685c-2cfd-0bc80fd80683@linux.intel.com>
        <b0037097-b917-9069-7d8f-07e0317d6b9f@linux.intel.com>
User-Agent: Wanderlust/2.15.9 (Almost Unreal) Emacs/27.2 Mule/6.0
MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue")
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 8bit
Precedence: bulk

On Tue, 25 Jul 2023 13:52:32 +0200,
Pierre-Louis Bossart wrote:
> 
> 
> >>>> @@ -121,6 +128,9 @@ static int i915_gfx_present(struct pci_dev
> >>>> *hdac_pci)
> >>>> ? {
> >>>> ????? struct pci_dev *display_dev = NULL;
> >>>> ? +??? if (!gpu_bind || (gpu_bind < 0 &&
> >>>> video_firmware_drivers_only()))
> >>>> +??????? return false;
> >>
> >>
> >> Bear with me since I am just going back to work mode but I can't figure
> >> out what the second part of the test does
> >>
> >> bool video_firmware_drivers_only(void)
> >> {
> >> ????return video_nomodeset;
> >> }
> >> EXPORT_SYMBOL(video_firmware_drivers_only);
> >>
> >> and video_nomodeset=1 by default, so why would we return false when
> >> gpu_bind = -1?
> >>
> >> This seems to be a change of functionality, what am I missing?
> > video_nomodeset is 0 by default, only when nomodeset is given as
> > argument is it set to 1. :-)
> 
> 
> I must be missing something on how the default is handled.
> 
> bool video_firmware_drivers_only(void)
> {
> 	return video_nomodeset;
> }
> EXPORT_SYMBOL(video_firmware_drivers_only);
> 
> static int __init disable_modeset(char *str)
> {
> 	video_nomodeset = true;
> 
> isn't default 'true' then?

disable_modeset() is called *only* when nomodeset boot option is
given.  Then it overrides the value to true.


Takashi