[PATCH v6 0/2] Add optional reset for the drm/imagination driver

[Matt Coster]

On 18/04/2025 12:22, Michal Wilczynski wrote:
> This patch series introduces and documents optional reset support for
> the drm/imagination driver. While developed as part of a larger effort
> to enable the Imagination BXM-4-64 GPU upstream, these patches can merge
> independently.
> 
> During the upstreaming process, we discovered that the T-HEAD TH1520 SoC
> requires custom code to manage resets and clocks from the power-domain
> driver [1]. Nevertheless, adding this reset capability is necessary, as
> the GPU Device Tree node would own the reset control and would manage it
> for boards like BPI-F3 that don't have custom requirements for handling
> clocks and resets during their startup sequence.
> 
> For more context, please see the cover letter for the larger series [2].

Hi Michal,

Thank you for persisting with these changes, I know we haven't always
made it easy for you!

This series (sub-series?) is:

Reviewed-by: Matt Coster <matt.coster at imgtec.com>

If nobody has any objections, I'll apply it to drm-misc-next tomorrow.

Cheers,
Matt

> 
> [1] - https://lore.kernel.org/all/20250414-apr_14_for_sending-v2-0-70c5af2af96c@samsung.com/ 
> [2] - https://lore.kernel.org/all/20250219140239.1378758-1-m.wilczynski@samsung.com/ 
> 
> This series is versioned to maintain continuity with the bigger patchset
> it is a subseries of. Please find below changelog for the
> drm/imagination reset part:
> 
> v6:
>  - no changes, just a re-send, bumping version to avoid confusion
> 
> v5:
>  - moved the recommended 1 microsecond delay after de-asserting GPU
>    reset to the Imagination driver itself 
> 
> v4:
>  - reverted reset-cells configuration to single cell as in v2
>  - addressed minor implementation issues in the DRM/Imagination reset driver
> 
> v3:
>  - refactored reset driver to use zero cells
> 
> v2:
>  - updated the drm/imagination driver to act as a reset controller
>    consumer. While this patchset is focused on the LPI4A board, the
>    reset controller is designed to be useful for other boards, such as the
>    BPI-3F, which also require a reset sequence after power-up.
> 
> ---
> Michal Wilczynski (2):
>       dt-bindings: gpu: Add 'resets' property for GPU initialization
>       drm/imagination: Add reset controller support for GPU initialization
> 
>  .../devicetree/bindings/gpu/img,powervr-rogue.yaml |  3 +++
>  drivers/gpu/drm/imagination/pvr_device.c           | 21 +++++++++++++++++++++
>  drivers/gpu/drm/imagination/pvr_device.h           |  9 +++++++++
>  drivers/gpu/drm/imagination/pvr_power.c            | 22 +++++++++++++++++++++-
>  4 files changed, 54 insertions(+), 1 deletion(-)
> ---
> base-commit: fc96b232f8e7c0a6c282f47726b2ff6a5fb341d2
> change-id: 20250418-apr_18_reset_img-b102988052de
> 
> Best regards,


-- 
Matt Coster
E: matt.coster at imgtec.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: OpenPGP_signature.asc
Type: application/pgp-signature
Size: 236 bytes
Desc: OpenPGP digital signature
URL: <https://lists.freedesktop.org/archives/dri-devel/attachments/20250422/63ec1fd8/attachment.sig>