Re: [PATCH 3/4] [v5] drm/i915/color: Extract icl_read_luts()

Sharma, Swati2
2019-10-15T14:04:23Z

On 15-Oct-19 6:04 PM, Ville Syrjälä wrote:
> On Thu, Oct 10, 2019 at 04:20:04PM +0530, Sharma, Swati2 wrote:
>> On 09-Oct-19 7:46 PM, Ville Syrjälä wrote:
>>> On Wed, Oct 09, 2019 at 12:25:41PM +0530, Swati Sharma wrote:
>>>> For icl+, have hw read out to create hw blob of gamma
>>>> lut values. icl+ platforms supports multi segmented gamma
>>>> mode by default, add hw lut creation for this mode.
>>>>
>>>> This will be used to validate gamma programming using dsb
>>>> (display state buffer) which is a tgl specific feature.
>>>>
>>>> Major change done-removal of readouts of coarse and fine segments
>>>> because PAL_PREC_DATA register isn't giving propoer values.
>>>> State checker limited only to "fine segment"
>>>>
>>>> v2: -readout code for multisegmented gamma has to come
>>>> up with some intermediate entries that aren't preserved
>>>> in hardware (Jani N)
>>>> -linear interpolation (Ville)
>>>> -moved common code to check gamma_enable to specific funcs,
>>>> since icl doesn't support that
>>>> v3: -use u16 instead of __u16 [Jani N]
>>>> -used single lut [Jani N]
>>>> -improved and more readable for loops [Jani N]
>>>> -read values directly to actual locations and then fill gaps [Jani N]
>>>> -moved cleaning to patch 1 [Jani N]
>>>> -renamed icl_read_lut_multi_seg() to icl_read_lut_multi_segment to
>>>> make it similar to icl_load_luts()
>>>> -renamed icl_compute_interpolated_gamma_blob() to
>>>> icl_compute_interpolated_gamma_lut_values() more sensible, I guess
>>>> v4: -removed interpolated func for creating gamma lut values
>>>> -removed readouts of fine and coarse segments, failure to read PAL_PREC_DATA
>>>> correctly
>>>> v5: -added gamma_enable check inside read_luts()
>>>>
>>>> Signed-off-by: Swati Sharma <swati2.sharma@intel.com>
>>>> ---
>>>> drivers/gpu/drm/i915/display/intel_color.c | 114 ++++++++++++++++++---
>>>> drivers/gpu/drm/i915/i915_reg.h | 6 ++
>>>> 2 files changed, 108 insertions(+), 12 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/i915/display/intel_color.c b/drivers/gpu/drm/i915/display/intel_color.c
>>>> index fa44eb73d088..614e0ad386ca 100644
>>>> --- a/drivers/gpu/drm/i915/display/intel_color.c
>>>> +++ b/drivers/gpu/drm/i915/display/intel_color.c
>>>> @@ -1477,6 +1477,25 @@ static int glk_gamma_precision(const struct intel_crtc_state *crtc_state)
>>>> }
>>>> }
>>>>
>>>> +static int icl_gamma_precision(const struct intel_crtc_state *crtc_state)
>>>> +{
>>>> + if ((crtc_state->gamma_mode & POST_CSC_GAMMA_ENABLE) == 0)
>>>> + return 0;
>>>> +
>>>> + switch (crtc_state->gamma_mode & GAMMA_MODE_MODE_MASK) {
>>>> + case GAMMA_MODE_MODE_8BIT:
>>>> + return 8;
>>>> + case GAMMA_MODE_MODE_10BIT:
>>>> + return 10;
>>>> + case GAMMA_MODE_MODE_12BIT_MULTI_SEGMENTED:
>>>> + return 16;
>>>> + default:
>>>> + MISSING_CASE(crtc_state->gamma_mode);
>>>> + return 0;
>>>> + }
>>>> +
>>>> +}
>>>> +
>>>> int intel_color_get_gamma_bit_precision(const struct intel_crtc_state *crtc_state)
>>>> {
>>>> struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
>>>> @@ -1488,7 +1507,9 @@ int intel_color_get_gamma_bit_precision(const struct intel_crtc_state *crtc_stat
>>>> else
>>>> return i9xx_gamma_precision(crtc_state);
>>>> } else {
>>>> - if (IS_CANNONLAKE(dev_priv) || IS_GEMINILAKE(dev_priv))
>>>> + if (INTEL_GEN(dev_priv) >= 11)
>>>> + return icl_gamma_precision(crtc_state);
>>>> + else if (IS_CANNONLAKE(dev_priv) || IS_GEMINILAKE(dev_priv))
>>>> return glk_gamma_precision(crtc_state);
>>>> else if (IS_IRONLAKE(dev_priv))
>>>> return ilk_gamma_precision(crtc_state);
>>>> @@ -1519,6 +1540,20 @@ static bool intel_color_lut_entry_equal(struct drm_color_lut *lut1,
>>>> return true;
>>>> }
>>>>
>>>> +static bool intel_color_lut_entry_multi_equal(struct drm_color_lut *lut1,
>>>> + struct drm_color_lut *lut2,
>>>> + int lut_size, u32 err)
>>>> +{
>>>> + int i;
>>>> +
>>>> + for (i = 0; i < 9; i++) {
>>>> + if (!err_check(&lut1[i], &lut2[i], err))
>>>> + return false;
>>>> + }
>>>> +
>>>> + return true;
>>>> +}
>>>> +
>>>> bool intel_color_lut_equal(struct drm_property_blob *blob1,
>>>> struct drm_property_blob *blob2,
>>>> u32 gamma_mode, u32 bit_precision)
>>>> @@ -1537,16 +1572,8 @@ bool intel_color_lut_equal(struct drm_property_blob *blob1,
>>>> lut_size2 = drm_color_lut_size(blob2);
>>>>
>>>> /* check sw and hw lut size */
>>>> - switch (gamma_mode) {
>>>> - case GAMMA_MODE_MODE_8BIT:
>>>> - case GAMMA_MODE_MODE_10BIT:
>>>> - if (lut_size1 != lut_size2)
>>>> - return false;
>>>> - break;
>>>> - default:
>>>> - MISSING_CASE(gamma_mode);
>>>> - return false;
>>>> - }
>>>> + if (lut_size1 != lut_size2)
>>>> + return false;
>>>>
>>>> lut1 = blob1->data;
>>>> lut2 = blob2->data;
>>>> @@ -1554,13 +1581,18 @@ bool intel_color_lut_equal(struct drm_property_blob *blob1,
>>>> err = 0xffff >> bit_precision;
>>>>
>>>> /* check sw and hw lut entry to be equal */
>>>> - switch (gamma_mode) {
>>>> + switch (gamma_mode & GAMMA_MODE_MODE_MASK) {
>>>> case GAMMA_MODE_MODE_8BIT:
>>>> case GAMMA_MODE_MODE_10BIT:
>>>> if (!intel_color_lut_entry_equal(lut1, lut2,
>>>> lut_size2, err))
>>>> return false;
>>>> break;
>>>> + case GAMMA_MODE_MODE_12BIT_MULTI_SEGMENTED:
>>>> + if (!intel_color_lut_entry_multi_equal(lut1, lut2,
>>>> + lut_size2, err))
>>>
>>> I don't think you need a new function for that. Just pass 9 as the size
>>> to intel_color_lut_entry_equal() ?
>>
>> I had made a separate function for multi-segmented gamma since there
>> will be 3 loops for comparing superfine, fine and course segments which
>> wont go with intel_lut_entry_equal() structure.
>>
>> Right now we are limiting to superfine segment only but in future we
>> will add for other segments too (once we get fix from h/w)
>>
>> Func() should look like this. Actually there is no need to passing
>> lut_size only in this function if we continue with this function only.
>>
>> +static bool intel_color_lut_entry_multi_equal(struct drm_color_lut *lut1,
>> + struct drm_color_lut *lut2,
>> + int lut_size, u32 err)
>> +{
>> + int i;
>> +
>> + for (i = 0; i < 9; i++) {
>> + if (!err_check(&lut1[i], &lut2[i], err))
>> + return false;
>> + }
>> +
>> + for (i = 1; i < 257; i++) {
>> + if (!err_check(&lut1[i * 8], &lut2[i * 8], err))
>> + return false;
>> + }
>> +
>> + for (i = 0; i < 256; i++) {
>> + if (!err_check(&lut1[i * 8 * 128], &lut2[i * 8 * 128], err))
>> + return false;
>> + }
>> +
>> + return true;
>> +}
>> +
>> Please suggest.
>
> There's not much point in duplicating code until it's proven to
> be required. Who knows when the hw gets fixed, maybe never.
Now, got your point. Thanks!
>
>>
>>>
>>> Hmm, should probably rename that to just intel_color_lut_equal() since
>>> it checks the entire LUT (or at least the specified subset) and not
>>> just a single entry...
Already intel_color_lut_equal() function exits, should i rename that to
intel_color_blob_equal() or intel_color_gamma_blob()? and make this func
intel_color_lut_entry_equal() to intel_color_lut_equal() as suggested by
you?
Please comment!
>>
>> This will be fine for this segment but for other two segments it won't
>> work. Right?
>
> We could generalize it to take start+end+stride. Dunno if that would be
> particularly beneficial though.
>

--
~Swati Sharma