[Intel-gfx] [PATCH 1/2] drm/i915/hdmi: call intel_hdmi_prepare for CHV

[Yang, Libin]

Hi Daniel,

Get it. Thanks.

Regards,
Libin

> -----Original Message-----
> From: daniel.vetter at ffwll.ch [mailto:daniel.vetter at ffwll.ch] On Behalf Of
> Daniel Vetter
> Sent: Thursday, July 31, 2014 5:51 PM
> To: Yang, Libin
> Cc: intel-gfx at lists.freedesktop.org
> Subject: Re: [Intel-gfx] [PATCH 1/2] drm/i915/hdmi: call intel_hdmi_prepare
> for CHV
> 
> On Thu, Jul 31, 2014 at 9:16 AM, Yang, Libin <libin.yang at intel.com> wrote:
> > BTW: I'm not familiar with gfx driver. But I see intel_hdmi_prepare() is
> called in the pre_pll_enable() for chv and vlv, but in others, it is called in
> pre_enable(). Could you tell me what's the difference between the two
> functions? I'm not sure if there is some impact on the audio function.
> 
> Depending upon the platform the exact modeset sequence is not always the
> same. So we mix&match and put the different stages at the right step. Which
> means the hdmi_prepare step isn't called on all platforms from exactly the
> same functions - platforms other than vlv/chv don't even have a
> pre_pll_enable step in the hdmi encoder.
> 
> It's a bit complicated, but this way we can support pretty much all intel gfx
> ever shipped in one driver without massive amounts of duplicated code. I
> hope that explains the idea a bit.
> -Daniel
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> +41 (0) 79 365 57 48 - http://blog.ffwll.ch