RE: [PATCH v5 0/8] drm: rcar-du: Add Color Management Module (CMM)

From: Kalakodima Venkata Rajesh (RBEI/ECF3)
Date: Mon Nov 11 2019 - 06:27:25 EST


Hi Jacopo,

Please find comments below.

Best regards,

Rajesh Kv
RBEI/ECF3

> -----Original Message-----
> From: linux-kernel-owner@xxxxxxxxxxxxxxx <linux-kernel-
> owner@xxxxxxxxxxxxxxx> On Behalf Of Jacopo Mondi
> Sent: Tuesday, October 15, 2019 4:16 PM
> To: laurent.pinchart@xxxxxxxxxxxxxxxx;
> kieran.bingham+renesas@xxxxxxxxxxxxxxxx; geert@xxxxxxxxxxxxxx;
> horms@xxxxxxxxxxxx; uli+renesas@xxxxxxxx; Kalakodima Venkata Rajesh
> (RBEI/ECF3) <VenkataRajesh.Kalakodima@xxxxxxxxxxxx>
> Cc: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>; airlied@xxxxxxxx;
> daniel@xxxxxxxx; koji.matsuoka.xm@xxxxxxxxxxx; muroya@xxxxxxxxx; Harsha
> Manjula Mallikarjun (RBEI/ECF3) <Harsha.ManjulaMallikarjun@xxxxxxxxxxxx>;
> ezequiel@xxxxxxxxxxxxx; seanpaul@xxxxxxxxxxxx; linux-renesas-
> soc@xxxxxxxxxxxxxxx; dri-devel@xxxxxxxxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx
> Subject: [PATCH v5 0/8] drm: rcar-du: Add Color Management Module (CMM)
>
> References:
> A reference to the v1 cover letter, with some background on the CMM is
> available here:
> https://lkml.org/lkml/2019/6/6/583
> v2:
> https://lore.kernel.org/linux-renesas-soc/20190706140746.29132-10-
> jacopo+renesas@xxxxxxxxxx/
> v3:
> https://lore.kernel.org/linux-renesas-soc/20190825135154.11488-1-
> jacopo+renesas@xxxxxxxxxx/
> v4:
> https://lore.kernel.org/linux-renesas-soc/20190906135436.10622-1-
> jacopo+renesas@xxxxxxxxxx/
>
> Again, quite a consistent changelog, mostly due to the developments happened
> on Ezequiel's VOP unit following Sean's advices.
>
> I here implemented the same, and moved the CMM handling to the crtc being
> and enable callbacks. As a result the overall implementation results quite a lot
> simplified, mostly on the CMM driver side.
>
> I have dropped tags and acks on the CMM driver and CMM enablement patches
> in DU crtc driver because of the number of changes.
>
> A more detailed change log:
>
> - Rebased on renesas-devel-2019-10-07-v5.4-rc4
>
> * Bindings/DT
> - Included Rob's comments on the yaml file license and the use of 'OneOf'
> in the compatible property description
> - Use the bracketed style suggested by Kieran for the 'renesas,cmm' property
> introduced in patch 2
> - Re-order the properties in the SoC DTS files as suggested by Kieran
>
> * CMM/DU
> - As anticipated, moved CMM management to the crtc from the atomic commit
> tail
> helper where it was implemented in v4
> This allow to correctly support resume/suspend and proper ordering of the
> CMM
> enable and setup operations (enable -before- setup)
> - As a consequence the CMM driver is greatly simplified by removing the need
> to cache the LUT table entries provided to cmm_setup() and later re-apply
> them at enable time.
> - Better support handling of disabled CMM config option by returning -ENODEV
> at cmm_init() time as suggested by Kieran.
>
> * Testing
> I have tested by injecting a color inversion LUT table and enabling/disabling it
> every 50 displayed frames:
> https://jmondi.org/cgit/kmsxx/log/?h=gamma_lut
>
> CMM functionalities are retained between suspend/resume cycles (tested with
> suspend-to-idle) without requiring a re-programming of the LUT tables.
>
> Testing with real world use cases might be beneficial. Rajesh are you still
> interested in giving this series a spin

I have tested version v3 of CMM module with a demo application based on libdrm
library. I could successfully test setting of Gamma LUT.

Next step is to test on full featured graphics stack i.e. involving Weston and OpenGL.
Weston can set Gamma. I have to stop this work for a while due to other high prio activities.
I plan to resume soon.

>
> Laurent, Kieran, could we fast-track review of this and hopefully try to have it
> merged for v5.5 ?
>
> Thanks Ezequiel for having suggested me this solution.
>
> Thanks
> j
>
> Jacopo Mondi (8):
> dt-bindings: display: renesas,cmm: Add R-Car CMM documentation
> dt-bindings: display, renesas,du: Document cmms property
> drm: rcar-du: Add support for CMM
> drm: rcar-du: kms: Initialize CMM instances
> drm: rcar-du: crtc: Control CMM operations
> drm: rcar-du: crtc: Register GAMMA_LUT properties
> arm64: dts: renesas: Add CMM units to Gen3 SoCs
> drm: rcar-du: kms: Expand comment in vsps parsing routine
>
> .../bindings/display/renesas,cmm.yaml | 67 ++++++
> .../bindings/display/renesas,du.txt | 5 +
> arch/arm64/boot/dts/renesas/r8a7795.dtsi | 39 ++++
> arch/arm64/boot/dts/renesas/r8a7796.dtsi | 31 ++-
> arch/arm64/boot/dts/renesas/r8a77965.dtsi | 31 ++-
> arch/arm64/boot/dts/renesas/r8a77990.dtsi | 21 ++
> arch/arm64/boot/dts/renesas/r8a77995.dtsi | 21 ++
> drivers/gpu/drm/rcar-du/Kconfig | 7 +
> drivers/gpu/drm/rcar-du/Makefile | 1 +
> drivers/gpu/drm/rcar-du/rcar_cmm.c | 198 ++++++++++++++++++
> drivers/gpu/drm/rcar-du/rcar_cmm.h | 60 ++++++
> drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 89 ++++++++
> drivers/gpu/drm/rcar-du/rcar_du_crtc.h | 2 +
> drivers/gpu/drm/rcar-du/rcar_du_drv.h | 2 +
> drivers/gpu/drm/rcar-du/rcar_du_group.c | 5 +
> drivers/gpu/drm/rcar-du/rcar_du_group.h | 2 +
> drivers/gpu/drm/rcar-du/rcar_du_kms.c | 82 +++++++-
> drivers/gpu/drm/rcar-du/rcar_du_regs.h | 5 +
> 18 files changed, 665 insertions(+), 3 deletions(-) create mode 100644
> Documentation/devicetree/bindings/display/renesas,cmm.yaml
> create mode 100644 drivers/gpu/drm/rcar-du/rcar_cmm.c
> create mode 100644 drivers/gpu/drm/rcar-du/rcar_cmm.h
>
> --
> 2.23.0