Re: [PATCH v3 1/1] ALSA: hda - bug fix for invalid connection list of Haswell HDMI codec pins

Re: [PATCH v3 1/1] ALSA: hda - bug fix for invalid connection list of Haswell HDMI codec pins

[Takashi Iwai]

At Tue, 18 Dec 2012 16:59:15 -0500,
mengdong.lin@intel.com wrote:
> 
> From: Mengdong Lin <mengdong.lin@intel.com>
> 
> Haswell HDMI codec pins may report invalid connection list entries, which
> will cause failure to play audio via HDMI or Display Port.
> 
> So this patch adds fixup for Haswell to workaround this hardware issue:
> enable DP1.2 mode and override the pins' connection list entries with proper
> value.
> 
> Signed-off-by: Mengdong Lin <mengdong.lin@intel.com>
> Signed-off-by: Xingchao Wang <xingchao.wang@intel.com>

Thanks, applied now.


Takashi

> 
> diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
> index 71555cc..59abe73 100644
> --- a/sound/pci/hda/patch_hdmi.c
> +++ b/sound/pci/hda/patch_hdmi.c
> @@ -1687,6 +1687,30 @@ static const struct hda_codec_ops generic_hdmi_patch_ops = {
>  	.unsol_event		= hdmi_unsol_event,
>  };
>  
> +static void intel_haswell_fixup_connect_list(struct hda_codec *codec)
> +{
> +	unsigned int vendor_param;
> +	hda_nid_t list[3] = {0x2, 0x3, 0x4};
> +
> +	vendor_param = snd_hda_codec_read(codec, 0x08, 0, 0xf81, 0);
> +	if (vendor_param == -1 || vendor_param & 0x02)
> +		return;
> +
> +	/* enable DP1.2 mode */
> +	vendor_param |= 0x02;
> +	snd_hda_codec_read(codec, 0x08, 0, 0x781, vendor_param);
> +
> +	vendor_param = snd_hda_codec_read(codec, 0x08, 0, 0xf81, 0);
> +	if (vendor_param == -1 || !(vendor_param & 0x02))
> +		return;
> +
> +	/* override 3 pins connection list */
> +	snd_hda_override_conn_list(codec, 0x05, 3, list);
> +	snd_hda_override_conn_list(codec, 0x06, 3, list);
> +	snd_hda_override_conn_list(codec, 0x07, 3, list);
> +}
> +
> +
>  static int patch_generic_hdmi(struct hda_codec *codec)
>  {
>  	struct hdmi_spec *spec;
> @@ -1696,6 +1720,10 @@ static int patch_generic_hdmi(struct hda_codec *codec)
>  		return -ENOMEM;
>  
>  	codec->spec = spec;
> +
> +	if (codec->vendor_id == 0x80862807)
> +		intel_haswell_fixup_connect_list(codec);
> +
>  	if (hdmi_parse_codec(codec) < 0) {
>  		codec->spec = NULL;
>  		kfree(spec);
> -- 
> 1.7.9.5
> 

[PATCH v3 1/1] ALSA: hda - bug fix for invalid connection list of Haswell HDMI codec pins

[mengdong.lin]

From: Mengdong Lin <mengdong.lin@intel.com>

Haswell HDMI codec pins may report invalid connection list entries, which
will cause failure to play audio via HDMI or Display Port.

So this patch adds fixup for Haswell to workaround this hardware issue:
enable DP1.2 mode and override the pins' connection list entries with proper
value.

Signed-off-by: Mengdong Lin <mengdong.lin@intel.com>
Signed-off-by: Xingchao Wang <xingchao.wang@intel.com>

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index 71555cc..59abe73 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -1687,6 +1687,30 @@ static const struct hda_codec_ops generic_hdmi_patch_ops = {
 	.unsol_event		= hdmi_unsol_event,
 };
 
+static void intel_haswell_fixup_connect_list(struct hda_codec *codec)
+{
+	unsigned int vendor_param;
+	hda_nid_t list[3] = {0x2, 0x3, 0x4};
+
+	vendor_param = snd_hda_codec_read(codec, 0x08, 0, 0xf81, 0);
+	if (vendor_param == -1 || vendor_param & 0x02)
+		return;
+
+	/* enable DP1.2 mode */
+	vendor_param |= 0x02;
+	snd_hda_codec_read(codec, 0x08, 0, 0x781, vendor_param);
+
+	vendor_param = snd_hda_codec_read(codec, 0x08, 0, 0xf81, 0);
+	if (vendor_param == -1 || !(vendor_param & 0x02))
+		return;
+
+	/* override 3 pins connection list */
+	snd_hda_override_conn_list(codec, 0x05, 3, list);
+	snd_hda_override_conn_list(codec, 0x06, 3, list);
+	snd_hda_override_conn_list(codec, 0x07, 3, list);
+}
+
+
 static int patch_generic_hdmi(struct hda_codec *codec)
 {
 	struct hdmi_spec *spec;
@@ -1696,6 +1720,10 @@ static int patch_generic_hdmi(struct hda_codec *codec)
 		return -ENOMEM;
 
 	codec->spec = spec;
+
+	if (codec->vendor_id == 0x80862807)
+		intel_haswell_fixup_connect_list(codec);
+
 	if (hdmi_parse_codec(codec) < 0) {
 		codec->spec = NULL;
 		kfree(spec);
-- 
1.7.9.5

Re: [PATCH v3 1/1] ALSA: hda - bug fix for invalid connection list of Haswell HDMI codec pins

[David Henningsson]

On 12/18/2012 10:59 PM, mengdong.lin@intel.com wrote:
> From: Mengdong Lin <mengdong.lin@intel.com>
>
> Haswell HDMI codec pins may report invalid connection list entries, which
> will cause failure to play audio via HDMI or Display Port.
>
> So this patch adds fixup for Haswell to workaround this hardware issue:
> enable DP1.2 mode and override the pins' connection list entries with proper
> value.
>
> Signed-off-by: Mengdong Lin <mengdong.lin@intel.com>
> Signed-off-by: Xingchao Wang <xingchao.wang@intel.com>
>
> diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
> index 71555cc..59abe73 100644
> --- a/sound/pci/hda/patch_hdmi.c
> +++ b/sound/pci/hda/patch_hdmi.c
> @@ -1687,6 +1687,30 @@ static const struct hda_codec_ops generic_hdmi_patch_ops = {
>   	.unsol_event		= hdmi_unsol_event,
>   };
>
> +static void intel_haswell_fixup_connect_list(struct hda_codec *codec)
> +{
> +	unsigned int vendor_param;
> +	hda_nid_t list[3] = {0x2, 0x3, 0x4};
> +
> +	vendor_param = snd_hda_codec_read(codec, 0x08, 0, 0xf81, 0);
> +	if (vendor_param == -1 || vendor_param & 0x02)
> +		return;
> +
> +	/* enable DP1.2 mode */
> +	vendor_param |= 0x02;
> +	snd_hda_codec_read(codec, 0x08, 0, 0x781, vendor_param);

Hi,

When trying to get Haswell HDMI audio working, I discovered that this 
verb when executed can get pins to change state from D0 to D3.

As the fixup is executed after hda_call_codec_resume this means that the 
pins will remain in D3. I'm not entirely sure of this, but I think we 
have no runtime power transitions if we are on AC power, so this could 
potentially be for a very long time.

> +	/* override 3 pins connection list */
> +	snd_hda_override_conn_list(codec, 0x05, 3, list);
> +	snd_hda_override_conn_list(codec, 0x06, 3, list);
> +	snd_hda_override_conn_list(codec, 0x07, 3, list);

So before the DP 1.2 verb is executed, the connections are
just 5 -> 2, 6 -> 3, 7 -> 4, but afterwards, every pin node can connect 
to every cvt node, and connection select verbs must change as a result?


-- 
David Henningsson, Canonical Ltd.
https://launchpad.net/~diwic

Re: [PATCH v3 1/1] ALSA: hda - bug fix for invalid connection list of Haswell HDMI codec pins

[Takashi Iwai]

At Tue, 15 Jan 2013 11:51:23 +0100,
David Henningsson wrote:
> 
> On 12/18/2012 10:59 PM, mengdong.lin@intel.com wrote:
> > From: Mengdong Lin <mengdong.lin@intel.com>
> >
> > Haswell HDMI codec pins may report invalid connection list entries, which
> > will cause failure to play audio via HDMI or Display Port.
> >
> > So this patch adds fixup for Haswell to workaround this hardware issue:
> > enable DP1.2 mode and override the pins' connection list entries with proper
> > value.
> >
> > Signed-off-by: Mengdong Lin <mengdong.lin@intel.com>
> > Signed-off-by: Xingchao Wang <xingchao.wang@intel.com>
> >
> > diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
> > index 71555cc..59abe73 100644
> > --- a/sound/pci/hda/patch_hdmi.c
> > +++ b/sound/pci/hda/patch_hdmi.c
> > @@ -1687,6 +1687,30 @@ static const struct hda_codec_ops generic_hdmi_patch_ops = {
> >   	.unsol_event		= hdmi_unsol_event,
> >   };
> >
> > +static void intel_haswell_fixup_connect_list(struct hda_codec *codec)
> > +{
> > +	unsigned int vendor_param;
> > +	hda_nid_t list[3] = {0x2, 0x3, 0x4};
> > +
> > +	vendor_param = snd_hda_codec_read(codec, 0x08, 0, 0xf81, 0);
> > +	if (vendor_param == -1 || vendor_param & 0x02)
> > +		return;
> > +
> > +	/* enable DP1.2 mode */
> > +	vendor_param |= 0x02;
> > +	snd_hda_codec_read(codec, 0x08, 0, 0x781, vendor_param);
> 
> Hi,
> 
> When trying to get Haswell HDMI audio working, I discovered that this 
> verb when executed can get pins to change state from D0 to D3.

Oh, does this verb do it?  It's bad.

Also, Mengdong, could you define these verbs (0x781 & 0xf81) in
hda_codec.h to understand and read the code better?

> As the fixup is executed after hda_call_codec_resume this means that the 
> pins will remain in D3. I'm not entirely sure of this, but I think we 
> have no runtime power transitions if we are on AC power, so this could 
> potentially be for a very long time.

Actually you spotted a potential bug -- the code isn't called in the
resume callback.  This is a code called directly from
parse_generic_hdmi(), so it's called only once to override the
connections.  But the verb 0x781 isn't set.

I thought we can simply replace the call
 snd_hda_codec_read(codec, 0x08, 0, 0x781, ...)
with snd_hda_codec_write_cache(), so that the same verb will be
executed automatically on resume.  But, if this verb has any bad side
effect (like touching D state), it's no good idea to do it in the
cache resume.

> > +	/* override 3 pins connection list */
> > +	snd_hda_override_conn_list(codec, 0x05, 3, list);
> > +	snd_hda_override_conn_list(codec, 0x06, 3, list);
> > +	snd_hda_override_conn_list(codec, 0x07, 3, list);
> 
> So before the DP 1.2 verb is executed, the connections are
> just 5 -> 2, 6 -> 3, 7 -> 4, but afterwards, every pin node can connect 
> to every cvt node, and connection select verbs must change as a result?

This is my understanding, but maybe a bit more comments would be
helpful...


thanks,

Takashi

Re: [PATCH v3 1/1] ALSA: hda - bug fix for invalid connection list of Haswell HDMI codec pins

[Lin, Mengdong]

> -----Original Message-----
> From: David Henningsson [mailto:david.henningsson@canonical.com]
> Sent: Tuesday, January 15, 2013 6:51 PM


> When trying to get Haswell HDMI audio working, I discovered that this verb
> when executed can get pins to change state from D0 to D3.
> 
> As the fixup is executed after hda_call_codec_resume this means that the
> pins will remain in D3. I'm not entirely sure of this, but I think we have no
> runtime power transitions if we are on AC power, so this could potentially be
> for a very long time.

Hi David,

Is the "power save" enabled for the codec, by setting a non-zero value to the 
"power_save" parameter under /sys/module/snd_hda_intel/parametesrs?

The verb 0x0f81/0x0781/ is a vendor verb to query/configure HDMI, but it will
not touch the pin's D-state.

I suspect the codec is suspended in D3 during the interval between commands
execution, since codec_exec_verb() will call snd_hda_power_down() after a 
command is done and so the codec will be suspended if 'power save' is enabled. 
And snd_hda_codec_read() just tries to resume the codec when executing a 
new command, the calling sequence is snd_hda_codec_read-> codec_exec_verb
-> snd_hda_power_up.

> 
> > +	/* override 3 pins connection list */
> > +	snd_hda_override_conn_list(codec, 0x05, 3, list);
> > +	snd_hda_override_conn_list(codec, 0x06, 3, list);
> > +	snd_hda_override_conn_list(codec, 0x07, 3, list);
> 
> So before the DP 1.2 verb is executed, the connections are just 5 -> 2, 6 -> 3,
> 7 -> 4, but afterwards, every pin node can connect to every cvt node, and
> connection select verbs must change as a result?

Yes. Without DP 1.2 there is a 1:1 mapping between pins and convertors. But HDMI 
cannot play sound. And even DP 1.2 is enabled, HDMI codec can still report invalid 
empty connect list during initialization. This is a HW issue for Haswell B0 processor.

Which version of Haswell processor is on your machine? Could you share the 
'cpu stepping' in BIOS under platform information menu. 

We'll verify this issue and side effect of the patch after we got a processor upgrade.

Sorry for the late reply.

Thanks
Mengdong

Re: [PATCH v3 1/1] ALSA: hda - bug fix for invalid connection list of Haswell HDMI codec pins

[Lin, Mengdong]

> -----Original Message-----
> From: Takashi Iwai [mailto:tiwai@suse.de]
> Sent: Tuesday, January 15, 2013 7:33 PM
> > When trying to get Haswell HDMI audio working, I discovered that this
> > verb when executed can get pins to change state from D0 to D3.
> 
> Oh, does this verb do it?  It's bad.

No, I think these verbs ((0x781 & 0xf81) don't change pin state. 
So I'm asking David to share more Information.

> Also, Mengdong, could you define these verbs (0x781 & 0xf81) in
> hda_codec.h to understand and read the code better?

Okay, I will.

> > As the fixup is executed after hda_call_codec_resume this means that
> > the pins will remain in D3. I'm not entirely sure of this, but I think
> > we have no runtime power transitions if we are on AC power, so this
> > could potentially be for a very long time.
> 
> Actually you spotted a potential bug -- the code isn't called in the resume
> callback.  This is a code called directly from parse_generic_hdmi(), so it's
> called only once to override the connections.  But the verb 0x781 isn't set.

Yes. intel_haswell_fixup_connect_list() is called only once from 
parse_generic_hdmi().

> I thought we can simply replace the call  snd_hda_codec_read(codec, 0x08,
> 0, 0x781, ...) with snd_hda_codec_write_cache(), so that the same verb will
> be executed automatically on resume.  But, if this verb has any bad side
> effect (like touching D state), it's no good idea to do it in the cache resume.
> 

But at first, we need to find out whether snd_hda_codec_read (codec, 0x08, 0, 0x781, ...)
cannot bring the codec out of D3 before executing 0x781. I suspect it's not the executing
the verb but before that that the whole codec (including the pins) enters D3.

Thanks
Mengdong