On Fri, Jan 27, 2017 at 08:47:50AM -0600, Pierre-Louis Bossart wrote:
Thanks Jani and Ville for the comments. Couple of precisions needed below:
#define GEN6_BSD_RNCID _MMIO(0x12198)
#define GEN7_FF_THREAD_MODE _MMIO(0x20a0) diff --git a/drivers/gpu/drm/i915/intel_lpe_audio.c b/drivers/gpu/drm/i915/intel_lpe_audio.c index 245523e..b3134ef 100644 --- a/drivers/gpu/drm/i915/intel_lpe_audio.c +++ b/drivers/gpu/drm/i915/intel_lpe_audio.c @@ -248,6 +248,15 @@ static int lpe_audio_setup(struct drm_i915_private *dev_priv) goto err_free_irq; }
- /* Enable DPAudio debug bits by default */
- if (IS_CHERRYVIEW(dev_priv)) {
VLV too. And like I said we might need this in the powerwell code as well. You should make a test to see if the register value is retained across the display power well being turned off. Eg. simply disable all displays, check the log to make sure it really did turn off the display power well, then re-enable some displays, and finally check if the register value was retained or not).
VLV has DisplayPort?
Yes. And as I said earlier the docs don't make any distinciton between HDMI and DP in the audio programming sequence. So based on the docs we should always unmute the amp manually.
I thought this was an addition on CHT, and I really don't know of any devices with this combination of HDaudio disabled+DP. I'd rather keep this CHT-only until we find a device where this can be tested.
On the powerwell, I could use more guidance. i tried this first solution to see if streaming worked (and it did :-)). I don't mind moving the code somewhere else but I have no idea where.
1. boot with drm.debug=0xe 1. 'intel_reg read 0x62f38' just after boot, to see that the chicken bit is as it should 2. disable all displays (eg. xset dpms force off) 3. grep 'power_well.*display' (make sure the last thing it says is "disabling" 4. turn on the displays (eg. xset dpms force on) 5. 'intel_reg read 0x62f38' to check the chicken bit again
If it didn't survive then we need to set it in either in vlv_display_power_well_init(), or we could just set it whenever we set the AMP_MUTE bit for any of the ports.
u32 chicken_bit;chicken_bit = I915_READ(VLV_AUD_CHICKEN_BIT_REG);I915_WRITE(VLV_AUD_CHICKEN_BIT_REG,chicken_bit | CHICKEN_BIT_DBG_ENABLE);- }
- return 0; err_free_irq: irq_free_desc(dev_priv->lpe_audio.irq);
@@ -357,6 +366,24 @@ void intel_lpe_audio_notify(struct drm_i915_private *dev_priv, pdata->tmds_clock_speed = tmds_clk_speed; if (link_rate) pdata->link_rate = link_rate;
if (dp_output) { /* unmute the amp */The spec doesn't distinquish DP vs. HDMI here. So I presume we should be able to do this always.
I'll try to see if HDMI still works with this. We could tentatively add unmute in all cases but I'll need to add a test for Baytrail (no PORT_D) so in the end it's the same number of tests.
And I think we might want to mute things again when disabling audio.
I was wondering if there would be side effects of writing to a register controlling a port if that port is not connected any longer. I'll give it a try.
Nothing apart from HPD circuitry really cares if there's anything connectect or not.