public inbox for intel-gfx@lists.freedesktop.org
 help / color / mirror / Atom feed
From: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
To: Jani Nikula <jani.nikula@intel.com>
Cc: "Zhang, Keqiao" <keqiao.zhang@intel.com>,
	"intel-gfx@lists.freedesktop.org"
	<intel-gfx@lists.freedesktop.org>,
	"Zhao, Juan J" <juan.j.zhao@intel.com>,
	"Pandiyan, Dhinakaran" <dhinakaran.pandiyan@intel.com>,
	"libin.yang@linux.intel.com" <libin.yang@linux.intel.com>
Subject: Re: [PATCH RESEND 9/9] drm/i915: set proper N/M in modeset
Date: Thu, 20 Oct 2016 15:02:48 +0300	[thread overview]
Message-ID: <20161020120248.GQ4329@intel.com> (raw)
In-Reply-To: <87twc7qmnp.fsf@intel.com>

On Thu, Oct 20, 2016 at 02:34:34PM +0300, Jani Nikula wrote:
> On Thu, 20 Oct 2016, "Yang, Libin" <libin.yang@intel.com> wrote:
> >> >> Any particular reason these M/N values are half of what they're in
> >> >> table
> >> >> 2-104 of DP 1.4 spec? (Admittedly the table is an informative
> >> >> example.)
> >> >
> >> > For HDMI, we found only set N is enough. HW then can handle the
> >> remaining.
> >> 
> >> I meant, the M and N values in this part of the dp_aud_n_m table are 1/2 of
> >> what they are in the DP spec table. Why?
> >
> > Which table are you meaning? I calculate the values myself. I didn't find the
> > full table in DP spec. I only find the table for 270MHz and 162MHz in 
> > Table 2-50: Examples of Maud and Naud Values
> 
> Table 2-104 in DP 1.4. Maybe you're looking at an older version of the
> spec.

So it looks like they used the same M value for all link frequencies
in that example, which for 540M ends up being double what the minimal
accurate value is. But as both M and N are doubled the ratio is still
exactly the same.

And there is indeed a 64k and 128k bitrates added as well. Those are
not classified under HBR audio. But as those can't be expressed via
short audio descriptors in the EDID, I don't think they would be
accepted by ALSA. Or am I wrong? I do wonder how they are supposed to be
used though since there must be some way for the sink to advertise
them, otherwise I can't see the point in adding them.

-- 
Ville Syrjälä
Intel OTC
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

  reply	other threads:[~2016-10-20 12:02 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-10 15:03 [PATCH RESEND 0/9] drm/i915/audio: audio cleanups, 4k fixes Jani Nikula
2016-10-10 15:04 ` [PATCH RESEND 1/9] drm/i915/audio: abstract audio config update Jani Nikula
2016-10-11  1:59   ` Yang, Libin
2016-10-10 15:04 ` [PATCH RESEND 2/9] drm/i915/audio: port is going to be just fine, simplify checks Jani Nikula
2016-10-11  2:37   ` Yang, Libin
2016-10-10 15:04 ` [PATCH RESEND 3/9] drm/i915/audio: use the same code for updating audio config Jani Nikula
2016-10-11  5:25   ` Yang, Libin
2016-10-10 15:04 ` [PATCH RESEND 4/9] drm/i915/audio: split dp and hdmi audio config update Jani Nikula
2016-10-11  5:42   ` Yang, Libin
2016-10-10 15:04 ` [PATCH RESEND 5/9] drm/i915/audio: set proper N/MCTS on more platforms Jani Nikula
2016-10-10 15:04 ` [PATCH RESEND 6/9] drm/i915/audio: HDMI audio gets the TMDS clock by crtc_clock Jani Nikula
2016-10-10 15:04 ` [PATCH RESEND 7/9] drm/i915/audio: add register macros for audio config N value Jani Nikula
2016-10-11  5:52   ` Yang, Libin
2016-10-10 15:04 ` [PATCH RESEND 8/9] drm/i915/audio: rename N value getter to emphasize it's for hdmi Jani Nikula
2016-10-11  5:55   ` Yang, Libin
2016-10-11 14:25     ` Jani Nikula
2016-10-10 15:04 ` [PATCH RESEND 9/9] drm/i915: set proper N/M in modeset Jani Nikula
2016-10-12  2:45   ` Lin, Mengdong
2016-10-12  6:29     ` Yang, Libin
2016-10-19 15:08       ` Jani Nikula
2016-10-20  2:00         ` Yang, Libin
2016-10-20  8:33           ` Jani Nikula
2016-10-20  8:42             ` Yang, Libin
2016-10-20 11:34               ` Jani Nikula
2016-10-20 12:02                 ` Ville Syrjälä [this message]
2016-10-21  6:47                   ` Yang, Libin
2016-10-21  6:21                 ` Yang, Libin
2016-10-12  6:41   ` Zhang, Keqiao
2016-10-10 18:19 ` ✗ Fi.CI.BAT: warning for drm/i915/audio: audio cleanups, 4k fixes (rev3) Patchwork

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20161020120248.GQ4329@intel.com \
    --to=ville.syrjala@linux.intel.com \
    --cc=dhinakaran.pandiyan@intel.com \
    --cc=intel-gfx@lists.freedesktop.org \
    --cc=jani.nikula@intel.com \
    --cc=juan.j.zhao@intel.com \
    --cc=keqiao.zhang@intel.com \
    --cc=libin.yang@linux.intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox