mali_kbase hardcodes MAX_PM_DOMAINS (=5 for the mt8192 kernel). I have
no real objection to it but Angelo did. Maybe should've marked this RFC.
On Mon, Feb 14, 2022 at 03:31:32PM -0500, Alyssa Rosenzweig wrote:
> MT8192 requires 5 power domains. Rather than bump MAX_PM_DOMAINS and
> waste memory on every supported Panfrost chip, instead dynamically
> allocate pm_domain_devs and pm_domain_links. This adds some flexibility;
> it seems inevitable a new MediaTek device will require more than 5
> domains.
>
> On non-MediaTek devices, this saves a small amount of memory.
>
> Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
> Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@xxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/panfrost/panfrost_device.c | 14 ++++++++++----
> drivers/gpu/drm/panfrost/panfrost_device.h | 5 ++---
> 2 files changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c
> index ee612303f076..661cdec320af 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_device.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_device.c
> @@ -127,7 +127,10 @@ static void panfrost_pm_domain_fini(struct panfrost_device *pfdev)
> {
> int i;
>
> - for (i = 0; i < ARRAY_SIZE(pfdev->pm_domain_devs); i++) {
> + if (!pfdev->pm_domain_devs || !pfdev->pm_domain_links)
> + return;
> +
> + for (i = 0; i < pfdev->comp->num_pm_domains; i++) {
> if (!pfdev->pm_domain_devs[i])
> break;
>
> @@ -161,9 +164,12 @@ static int panfrost_pm_domain_init(struct panfrost_device *pfdev)
> return -EINVAL;
> }
>
> - if (WARN(num_domains > ARRAY_SIZE(pfdev->pm_domain_devs),
> - "Too many supplies in compatible structure.\n"))
> - return -EINVAL;
> + pfdev->pm_domain_devs = devm_kcalloc(pfdev->dev, num_domains,
> + sizeof(*pfdev->pm_domain_devs),
> + GFP_KERNEL);
> + pfdev->pm_domain_links = devm_kcalloc(pfdev->dev, num_domains,
> + sizeof(*pfdev->pm_domain_links),
> + GFP_KERNEL);
>
> for (i = 0; i < num_domains; i++) {
> pfdev->pm_domain_devs[i] =
> diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h
> index 8b25278f34c8..98e3039696f9 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_device.h
> +++ b/drivers/gpu/drm/panfrost/panfrost_device.h
> @@ -22,7 +22,6 @@ struct panfrost_job;
> struct panfrost_perfcnt;
>
> #define NUM_JOB_SLOTS 3
> -#define MAX_PM_DOMAINS 3
>
> struct panfrost_features {
> u16 id;
> @@ -87,8 +86,8 @@ struct panfrost_device {
> struct regulator_bulk_data *regulators;
> struct reset_control *rstc;
> /* pm_domains for devices with more than one. */
> - struct device *pm_domain_devs[MAX_PM_DOMAINS];
> - struct device_link *pm_domain_links[MAX_PM_DOMAINS];
> + struct device **pm_domain_devs;
> + struct device_link **pm_domain_links;
> bool coherent;
>
> struct panfrost_features features;
> --
> 2.34.1
>
