On Thu, 11 Aug 2022, "Deucher, Alexander" <Alexander.Deucher@xxxxxxx> wrote:
> [Public]
>
>> -----Original Message-----
>> From: amd-gfx <amd-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of Jani
>> Nikula
>> Sent: Thursday, August 4, 2022 5:55 AM
>> To: Jouni Högander <jouni.hogander@xxxxxxxxx>; dri-
>> devel@xxxxxxxxxxxxxxxxxxxxx; intel-gfx@xxxxxxxxxxxxxxxxxxxxx; amd-
>> gfx@xxxxxxxxxxxxxxxxxxxxx
>> Cc: Siqueira, Rodrigo <Rodrigo.Siqueira@xxxxxxx>; Li, Roman
>> <Roman.Li@xxxxxxx>; Manasi Navare <manasi.d.navare@xxxxxxxxx>; Mika
>> Kahola <mika.kahola@xxxxxxxxx>; Jouni Högander
>> <jouni.hogander@xxxxxxxxx>; Wentland, Harry
>> <Harry.Wentland@xxxxxxx>
>> Subject: Re: [PATCH v3 2/3] drm/amdgpu_dm: Rely on split out luminance
>> calculation function
>>
>> On Tue, 19 Jul 2022, Jouni Högander <jouni.hogander@xxxxxxxxx> wrote:
>> > Luminance range calculation was split out into drm_edid.c and is now
>> > part of edid parsing. Rely on values calculated during edid parsing
>> > and use these for caps->aux_max_input_signal and caps-
>> >aux_min_input_signal.
>>
>> Harry, I'll merge patches 1 & 3 in this series through drm-misc-next, because I
>> think they're good to go, and fix stuff in i915.
>>
>> Can I get your rb/ack to merge this patch as well, or do you want to take this
>> later via your tree?
>
> You can take this via drm-misc.
> Acked-by: Alex Deucher <alexander.deucher@xxxxxxx>
Thanks, pushed the series to drm-misc-next.
BR,
Jani.
>
>
>>
>> BR,
>> Jani.
>>
>>
>> >
>> > v2: Use values calculated during edid parsing
>> >
>> > Cc: Roman Li <roman.li@xxxxxxx>
>> > Cc: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
>> > Cc: Harry Wentland <harry.wentland@xxxxxxx>
>> > Cc: Lyude Paul <lyude@xxxxxxxxxx>
>> > Cc: Mika Kahola <mika.kahola@xxxxxxxxx>
>> > Cc: Jani Nikula <jani.nikula@xxxxxxxxx>
>> > Cc: Manasi Navare <manasi.d.navare@xxxxxxxxx>
>> > Signed-off-by: Jouni Högander <jouni.hogander@xxxxxxxxx>
>> > ---
>> > .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 35
>> > +++----------------
>> > 1 file changed, 4 insertions(+), 31 deletions(-)
>> >
>> > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> > b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> > index 3e83fed540e8..eb7abdeb8653 100644
>> > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> > @@ -2903,15 +2903,12 @@ static struct drm_mode_config_helper_funcs
>> > amdgpu_dm_mode_config_helperfuncs = {
>> >
>> > static void update_connector_ext_caps(struct amdgpu_dm_connector
>> > *aconnector) {
>> > - u32 max_avg, min_cll, max, min, q, r;
>> > struct amdgpu_dm_backlight_caps *caps;
>> > struct amdgpu_display_manager *dm;
>> > struct drm_connector *conn_base;
>> > struct amdgpu_device *adev;
>> > struct dc_link *link = NULL;
>> > - static const u8 pre_computed_values[] = {
>> > - 50, 51, 52, 53, 55, 56, 57, 58, 59, 61, 62, 63, 65, 66, 68, 69,
>> > - 71, 72, 74, 75, 77, 79, 81, 82, 84, 86, 88, 90, 92, 94, 96, 98};
>> > + struct drm_luminance_range_info *luminance_range;
>> > int i;
>> >
>> > if (!aconnector || !aconnector->dc_link) @@ -2933,8 +2930,6 @@
>> > static void update_connector_ext_caps(struct amdgpu_dm_connector
>> *aconnector)
>> > caps = &dm->backlight_caps[i];
>> > caps->ext_caps = &aconnector->dc_link->dpcd_sink_ext_caps;
>> > caps->aux_support = false;
>> > - max_avg = conn_base->hdr_sink_metadata.hdmi_type1.max_fall;
>> > - min_cll = conn_base->hdr_sink_metadata.hdmi_type1.min_cll;
>> >
>> > if (caps->ext_caps->bits.oled == 1 /*||
>> > caps->ext_caps->bits.sdr_aux_backlight_control == 1 || @@
>> > -2946,31 +2941,9 @@ static void update_connector_ext_caps(struct
>> amdgpu_dm_connector *aconnector)
>> > else if (amdgpu_backlight == 1)
>> > caps->aux_support = true;
>> >
>> > - /* From the specification (CTA-861-G), for calculating the maximum
>> > - * luminance we need to use:
>> > - * Luminance = 50*2**(CV/32)
>> > - * Where CV is a one-byte value.
>> > - * For calculating this expression we may need float point precision;
>> > - * to avoid this complexity level, we take advantage that CV is divided
>> > - * by a constant. From the Euclids division algorithm, we know that
>> CV
>> > - * can be written as: CV = 32*q + r. Next, we replace CV in the
>> > - * Luminance expression and get 50*(2**q)*(2**(r/32)), hence we
>> just
>> > - * need to pre-compute the value of r/32. For pre-computing the
>> values
>> > - * We just used the following Ruby line:
>> > - * (0...32).each {|cv| puts (50*2**(cv/32.0)).round}
>> > - * The results of the above expressions can be verified at
>> > - * pre_computed_values.
>> > - */
>> > - q = max_avg >> 5;
>> > - r = max_avg % 32;
>> > - max = (1 << q) * pre_computed_values[r];
>> > -
>> > - // min luminance: maxLum * (CV/255)^2 / 100
>> > - q = DIV_ROUND_CLOSEST(min_cll, 255);
>> > - min = max * DIV_ROUND_CLOSEST((q * q), 100);
>> > -
>> > - caps->aux_max_input_signal = max;
>> > - caps->aux_min_input_signal = min;
>> > + luminance_range = &conn_base->display_info.luminance_range;
>> > + caps->aux_min_input_signal = luminance_range->min_luminance;
>> > + caps->aux_max_input_signal = luminance_range->max_luminance;
>> > }
>> >
>> > void amdgpu_dm_update_connector_after_detect(
>>
>> --
>> Jani Nikula, Intel Open Source Graphics Center
--
Jani Nikula, Intel Open Source Graphics Center
