On 2024-04-12 16:22, Harry Wentland wrote: > > > On 2024-04-12 12:26, Melissa Wen wrote: >> On 04/12, Joshua Ashton wrote: >>> >>> >>> On 4/11/24 3:26 PM, Melissa Wen wrote: >>>> On 04/10, Joshua Ashton wrote: >>>>> The comment here states "no OGAM in DPP since DCN1", yet that is not >>>>> true. >>>>> >>>>> Testing on an RX 7900XTX (dcn32), it actually does exist in hardware and >>>>> works fine. >>>>> My best guess is the comment is confused with OGAM ROM for DPP, rather >>>>> than OGAM RAM. >>>>> >>>>> I did not test dcn35/351 as I do not have that hardware, but I assume >>>>> the same follows there given the seemingly erroneous comment. >>>>> Someone at AMD should check that before merging this commit. >>>> >>>> hmm... I don't have any of these hw versions, but AFAIU if there is >>>> ogam/blend lut block in dcn32, the helper implementation for programming >>>> it properly (i.e. dpp_program_blnd_lut) is also missing here: >>>> - https://gitlab.freedesktop.org/agd5f/linux/-/blob/amd-staging-drm-next/drivers/gpu/drm/amd/display/dc/dpp/dcn32/dcn32_dpp.c#L125 >>>> right? So, it's good if AMD people can check it too. >>>> >>>> Melissa >>> >>> Hmm, yes. But, see dcn32_set_mcm_luts, that seems to handle per-plane blend >>> + shaper + 3D LUT state which is equivalent to what existed before? >> >> oh, cool! nice finding. blnd_lut is set on plane state, but programmed >> on MPC now. >> >> But I see the color pipeline changed in many stages from this version: >> - shaper + 3dlut before **or** after blending, but not before **and** after? >> - where post-blending gamut_remap_matrix is located now in this >> pipeline with mpcc postblend_1dlut and shaper+3dlut with mutable >> position? >> I guess something like: >> - [shaper -> 3dlut -> blnd_lut] -> ctm -> regamma ?? > > [1dlut -> 3dlut -> 1dlut] is now a movable block, called Movable CM > (color management), or MCM for short. It can occur before blending or > after. Because of that it moved to MPC (multi-plane combiner). > > If it's positioned for pre-blending it looks like this: > > DPP -> MCM -> BLND -> Blending -> Gamut Remap -> Out Gam -> OPP -> ... > > If it's positioned for post-blending it looks like this: > > DPP -> BLND -> Blending -> MCM -> Gamut Remap -> Out Gam -> OPP > > This is the case since DCN 3.2. > > Because of that you don't have an ogam_ram in dpp anymore for DCN 3.2 > and newer. > >>> >>> Therefore, I think I am actually wrong with enabling the ogam_ram in DPP cap >>> here, and the right solution is to change the check for exposing the >>> property to account for these LUTs being available per-plane with mcm. >>> >>> (what is mcm btw...? lots of acronyms and stuff moving around in hw hehe) >> >> yes, shaper, 3dlut, blend_lut don't seem DPP caps anymore. MCM looks >> like a component of MPC, so I think we need new mpc.color caps to >> describe them properly (?) >> >> I also didn't find in the Linux/AMD glossary or code comment that >> describe what MCM is... >> >>> >>> What's a good way for us to check for that? Seems like the caps don't help >>> much there. We could check for the literal function ptr I guess...? >>> >>> What are your thoughts, Harry and Melissa? >> > > I wonder if it makes sense to add an mcm cap to mpc_color_caps. Will need to > chat with some people about that. > I dug through the code a bit and talked with our resident expert. It looks like all the programming for in_shaper_func, lut_3d_func, and blend_tf should still work and assume a fixed pre-blending mcm, which is what we want. Caps don't really reflect MCM very well yet. We could either add an mcm flag to mpc_color_caps or simply check that DCN is 3.2 or newer: amdgpu_ip_version(adev, DCE_HWIP, 0) >= IP_VERSION(3, 2, 0) Harry > Harry > >> yeah, AFAIK color caps values are manually set and may contain >> misleading information. I'm unsure that using function ptr would solve >> the issue of having undocumented caps introduced to the color pipeline, >> such as MCM, but your suggestion seems more reliable. >> >> Anyway, the timing where the color pipeline was merged didn't help, but >> if new caps and functions are not documented and the DM handles are not >> updated accordingly, we will have the same issue in the future. >> For example, I see two new ptrs were introduced and implemented here: >> - https://gitlab.freedesktop.org/agd5f/linux/-/commit/a820190204aef >> - https://gitlab.freedesktop.org/agd5f/linux/-/commit/90f33674a0756 >> and we would need to update the DM color mgmt anyway to check these >> new/unknown functions. >> >> Seems okay if we check program_1dlut instead of ogam_ram caps, but what >> should we do for dpp/mpc shaper+3d lut in set_mcm_luts? I mean, should >> we enable plane or CRTC shaper+3dlut on DM? x_X >> >> Anyway, thanks for all these findings! >> >> I would like to hear more from AMD too. >> >> Melissa >> >>> >>> - Joshie 🐸✨ >>> >>>> >>>>> >>>>> Signed-off-by: Joshua Ashton <joshua@xxxxxxxxx> >>>>> >>>>> Cc: Harry Wentland <harry.wentland@xxxxxxx> >>>>> Cc: Xaver Hugl <xaver.hugl@xxxxxxxxx> >>>>> Cc: Melissa Wen <mwen@xxxxxxxxxx> >>>>> Cc: Ethan Lee <flibitijibibo@xxxxxxxxx> >>>>> --- >>>>> drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c | 2 +- >>>>> drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c | 2 +- >>>>> .../gpu/drm/amd/display/dc/resource/dcn351/dcn351_resource.c | 2 +- >>>>> 3 files changed, 3 insertions(+), 3 deletions(-) >>>>> >>>>> diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c >>>>> index 9aa39bd25be9..94f5d2b5aadf 100644 >>>>> --- a/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c >>>>> +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c >>>>> @@ -2182,7 +2182,7 @@ static bool dcn32_resource_construct( >>>>> dc->caps.color.dpp.dgam_rom_for_yuv = 0; >>>>> dc->caps.color.dpp.hw_3d_lut = 1; >>>>> - dc->caps.color.dpp.ogam_ram = 0; // no OGAM in DPP since DCN1 >>>>> + dc->caps.color.dpp.ogam_ram = 1; >>>>> // no OGAM ROM on DCN2 and later ASICs >>>>> dc->caps.color.dpp.ogam_rom_caps.srgb = 0; >>>>> dc->caps.color.dpp.ogam_rom_caps.bt2020 = 0; >>>>> diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c >>>>> index 25ac450944e7..708d63cc3f7f 100644 >>>>> --- a/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c >>>>> +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c >>>>> @@ -1861,7 +1861,7 @@ static bool dcn35_resource_construct( >>>>> dc->caps.color.dpp.dgam_rom_for_yuv = 0; >>>>> dc->caps.color.dpp.hw_3d_lut = 1; >>>>> - dc->caps.color.dpp.ogam_ram = 0; // no OGAM in DPP since DCN1 >>>>> + dc->caps.color.dpp.ogam_ram = 1; >>>>> // no OGAM ROM on DCN301 >>>>> dc->caps.color.dpp.ogam_rom_caps.srgb = 0; >>>>> dc->caps.color.dpp.ogam_rom_caps.bt2020 = 0; >>>>> diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn351/dcn351_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn351/dcn351_resource.c >>>>> index 8a57adb27264..053e8ec6d1ef 100644 >>>>> --- a/drivers/gpu/drm/amd/display/dc/resource/dcn351/dcn351_resource.c >>>>> +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn351/dcn351_resource.c >>>>> @@ -1841,7 +1841,7 @@ static bool dcn351_resource_construct( >>>>> dc->caps.color.dpp.dgam_rom_for_yuv = 0; >>>>> dc->caps.color.dpp.hw_3d_lut = 1; >>>>> - dc->caps.color.dpp.ogam_ram = 0; // no OGAM in DPP since DCN1 >>>>> + dc->caps.color.dpp.ogam_ram = 1; >>>>> // no OGAM ROM on DCN301 >>>>> dc->caps.color.dpp.ogam_rom_caps.srgb = 0; >>>>> dc->caps.color.dpp.ogam_rom_caps.bt2020 = 0; >>>>> -- >>>>> 2.44.0 >>>>>
