Re: [PATCH v2 2/2] drm/panfrost: Add support for Mali on the MT8188 SoC

[Steven Price]

On 04/06/2024 13:39, AngeloGioacchino Del Regno wrote:
> MediaTek MT8188 has a Mali-G57 MC3 (Valhall-JM): add a new
> compatible and platform data using the same supplies and the
> same power domain lists as MT8183 (one regulator, three power
> domains).
> 
> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/panfrost/panfrost_drv.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c
> index ef9f6c0716d5..4e2d9f671a0d 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_drv.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c
> @@ -777,6 +777,14 @@ static const struct panfrost_compatible mediatek_mt8186_data = {
>  	.pm_features = BIT(GPU_PM_CLK_DIS) | BIT(GPU_PM_VREG_OFF),
>  };
>  
> +static const struct panfrost_compatible mediatek_mt8188_data = {
> +	.num_supplies = ARRAY_SIZE(mediatek_mt8183_b_supplies) - 1,
> +	.supply_names = mediatek_mt8183_b_supplies,

I think this is a little confusing. Ideally we'd drop the existing
mediatek_xxx_supplies which are the same as default_supplies and just
use that instead.

> +	.num_pm_domains = ARRAY_SIZE(mediatek_mt8183_pm_domains),
> +	.pm_domain_names = mediatek_mt8183_pm_domains,

We'd want at least a comment explaining that this isn't a typo (i.e. /*
mt8188 uses the same pm domains as mt8183 */). But I'm also wondering if
it would be sensible to simply have one domain list, something like:

--->8---
static const char * const mediatek_pm_domains[] = { "core0", "core1",
						    "core2", "core3",
						    "core4" };

static const struct panfrost_compatible mediatek_mt8183_data = {
	...
	.num_pm_domains = 3,
	.pm_domain_names = mediatek_pm_domains,
};
...
static const struct panfrost_compatible mediatek_mt8186_data = {
	...
	.num_pm_domains = 2,
	.pm_domain_names = mediatek_pm_domains,
};
...
static const struct panfrost_compatible mediatek_mt8188_data = {
	...
	.num_pm_domains = 3,
	.pm_domain_names = mediatek_pm_domains,
};
...
static const struct panfrost_compatible mediatek_mt8192_data = {
	...
	.num_pm_domains = 5,
	.pm_domain_names = mediatek_pm_domains,
};
--->8---

OTOH what you've got it no worse than what we already had, so it's up to
you whether you want to tidy this up or just add a comment so it doesn't
look like there's a typo.

Steve

> +	.pm_features = BIT(GPU_PM_CLK_DIS) | BIT(GPU_PM_VREG_OFF),
> +};
> +
>  static const char * const mediatek_mt8192_supplies[] = { "mali", NULL };
>  static const char * const mediatek_mt8192_pm_domains[] = { "core0", "core1", "core2",
>  							   "core3", "core4" };
> @@ -808,6 +816,7 @@ static const struct of_device_id dt_match[] = {
>  	{ .compatible = "mediatek,mt8183-mali", .data = &mediatek_mt8183_data },
>  	{ .compatible = "mediatek,mt8183b-mali", .data = &mediatek_mt8183_b_data },
>  	{ .compatible = "mediatek,mt8186-mali", .data = &mediatek_mt8186_data },
> +	{ .compatible = "mediatek,mt8188-mali", .data = &mediatek_mt8188_data },
>  	{ .compatible = "mediatek,mt8192-mali", .data = &mediatek_mt8192_data },
>  	{}
>  };