[Nouveau] [PATCH 5/6] kms/nv50: detect HDMI max MHz correctly

[Karol Herbst]

On Fri, Jul 20, 2018 at 5:58 PM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
> This removes user control to force a hdmimhz. Given the vast variety
> of hardware and display configurations out there, I don't see how a
> patch like this won't blow up in our faces.
>
> I'm not saying we shouldn't do it -- we should attempt to respect the
> various maximums in the vbios, but until we get a solid handle on
> things, we should allow more user-configurability, not less, for the
> case where we get it wrong.
>

yeah, probably a good idea. I also removed the cap to 297 without
removing the comment. Shame on me.

> 2018-07-20 11:17 GMT-04:00 Karol Herbst <kherbst at redhat.com>:
>> Signed-off-by: Karol Herbst <kherbst at redhat.com>
>> ---
>>  drm/nouveau/dispnv50/disp.c     | 5 +++++
>>  drm/nouveau/nouveau_connector.c | 5 +++++
>>  drm/nouveau/nouveau_encoder.h   | 4 ++++
>>  3 files changed, 14 insertions(+)
>>
>> diff --git a/drm/nouveau/dispnv50/disp.c b/drm/nouveau/dispnv50/disp.c
>> index 6f41a6a0..3a960664 100644
>> --- a/drm/nouveau/dispnv50/disp.c
>> +++ b/drm/nouveau/dispnv50/disp.c
>> @@ -1433,7 +1433,12 @@ nv50_sor_create(struct drm_connector *connector, struct dcb_output *dcbe,
>>         case DCB_OUTPUT_LVDS: type = DRM_MODE_ENCODER_LVDS; break;
>>         case DCB_OUTPUT_DP:
>>                 nv_encoder->dp.no_interlace = caps->dp[or].no_interlace;
>> +               type = DRM_MODE_ENCODER_TMDS;
>> +               break;
>>         case DCB_OUTPUT_TMDS:
>> +               nv_encoder->tmds.max_mhz = caps->tmds[or].max_mhz;
>> +               type = DRM_MODE_ENCODER_TMDS;
>> +               break;
>>         default:
>>                 type = DRM_MODE_ENCODER_TMDS;
>>                 break;
>> diff --git a/drm/nouveau/nouveau_connector.c b/drm/nouveau/nouveau_connector.c
>> index 074e6d52..a955f225 100644
>> --- a/drm/nouveau/nouveau_connector.c
>> +++ b/drm/nouveau/nouveau_connector.c
>> @@ -980,9 +980,14 @@ static unsigned
>>  get_tmds_link_bandwidth(struct drm_connector *connector, bool hdmi)
>>  {
>>         struct nouveau_connector *nv_connector = nouveau_connector(connector);
>> +       struct nouveau_encoder *nv_encoder = nv_connector->detected_encoder;
>>         struct nouveau_drm *drm = nouveau_drm(connector->dev);
>>         struct dcb_output *dcb = nv_connector->detected_encoder->dcb;
>>
>> +       /* cap to 297MHz until we figure out HDMI 2.0 */
>> +       if (nv_encoder->tmds.max_mhz)
>> +               return nv_encoder->tmds.max_mhz * 1000;
>> +
>>         if (hdmi) {
>>                 if (nouveau_hdmimhz > 0)
>>                         return nouveau_hdmimhz * 1000;
>> diff --git a/drm/nouveau/nouveau_encoder.h b/drm/nouveau/nouveau_encoder.h
>> index f74af5ce..fbef9dc0 100644
>> --- a/drm/nouveau/nouveau_encoder.h
>> +++ b/drm/nouveau/nouveau_encoder.h
>> @@ -65,6 +65,10 @@ struct nouveau_encoder {
>>                         int link_bw;
>>                         bool no_interlace;
>>                 } dp;
>> +
>> +               struct {
>> +                       uint16_t max_mhz;
>> +               } tmds;
>>         };
>>
>>         void (*enc_save)(struct drm_encoder *encoder);
>> --
>> 2.17.1
>>
>> _______________________________________________
>> Nouveau mailing list
>> Nouveau at lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/nouveau