On Wed, 21 Dec 2022 at 18:14, Akhil P Oommen <quic_akhilpo@xxxxxxxxxxx> wrote:
>
> When a device has multiple power domains, dev->power_domain is left
> empty during probe. That didn't cause any issue so far because we are
> freeloading on smmu driver's vote on cx gdsc. Instead of that, create
> a device_link between cx genpd device and gmu device to keep a vote from
> gpu driver.
>
> Before this patch:
> localhost ~ # cat /sys/kernel/debug/pm_genpd/pm_genpd_summary
> gx_gdsc on 0
> /devices/genpd:1:3d6a000.gmu active 0
> cx_gdsc on 0
> /devices/platform/soc@0/3da0000.iommu active 0
>
> After this patch:
> localhost ~ # cat /sys/kernel/debug/pm_genpd/pm_genpd_summary
> gx_gdsc on 0
> /devices/genpd:1:3d6a000.gmu active 0
> cx_gdsc on 0
> /devices/platform/soc@0/3da0000.iommu active 0
> /devices/genpd:0:3d6a000.gmu active 0
>
> Signed-off-by: Akhil P Oommen <quic_akhilpo@xxxxxxxxxxx>
Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Kind regards
Uffe
> ---
>
> (no changes since v1)
>
> drivers/gpu/drm/msm/adreno/a6xx_gmu.c | 31 +++++++++++++++++++++++++++----
> drivers/gpu/drm/msm/adreno/a6xx_gmu.h | 1 +
> 2 files changed, 28 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
> index 6484b97c5344..1580d0090f35 100644
> --- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
> @@ -1479,6 +1479,12 @@ void a6xx_gmu_remove(struct a6xx_gpu *a6xx_gpu)
>
> pm_runtime_force_suspend(gmu->dev);
>
> + /*
> + * Since cxpd is a virt device, the devlink with gmu-dev will be removed
> + * automatically when we do detach
> + */
> + dev_pm_domain_detach(gmu->cxpd, false);
> +
> if (!IS_ERR_OR_NULL(gmu->gxpd)) {
> pm_runtime_disable(gmu->gxpd);
> dev_pm_domain_detach(gmu->gxpd, false);
> @@ -1605,8 +1611,10 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
>
> if (adreno_is_a650_family(adreno_gpu)) {
> gmu->rscc = a6xx_gmu_get_mmio(pdev, "rscc");
> - if (IS_ERR(gmu->rscc))
> + if (IS_ERR(gmu->rscc)) {
> + ret = -ENODEV;
> goto err_mmio;
> + }
> } else {
> gmu->rscc = gmu->mmio + 0x23000;
> }
> @@ -1615,8 +1623,22 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
> gmu->hfi_irq = a6xx_gmu_get_irq(gmu, pdev, "hfi", a6xx_hfi_irq);
> gmu->gmu_irq = a6xx_gmu_get_irq(gmu, pdev, "gmu", a6xx_gmu_irq);
>
> - if (gmu->hfi_irq < 0 || gmu->gmu_irq < 0)
> + if (gmu->hfi_irq < 0 || gmu->gmu_irq < 0) {
> + ret = -ENODEV;
> + goto err_mmio;
> + }
> +
> + gmu->cxpd = dev_pm_domain_attach_by_name(gmu->dev, "cx");
> + if (IS_ERR(gmu->cxpd)) {
> + ret = PTR_ERR(gmu->cxpd);
> goto err_mmio;
> + }
> +
> + if (!device_link_add(gmu->dev, gmu->cxpd,
> + DL_FLAG_PM_RUNTIME)) {
> + ret = -ENODEV;
> + goto detach_cxpd;
> + }
>
> /*
> * Get a link to the GX power domain to reset the GPU in case of GMU
> @@ -1634,6 +1656,9 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
>
> return 0;
>
> +detach_cxpd:
> + dev_pm_domain_detach(gmu->cxpd, false);
> +
> err_mmio:
> iounmap(gmu->mmio);
> if (platform_get_resource_byname(pdev, IORESOURCE_MEM, "rscc"))
> @@ -1641,8 +1666,6 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
> free_irq(gmu->gmu_irq, gmu);
> free_irq(gmu->hfi_irq, gmu);
>
> - ret = -ENODEV;
> -
> err_memory:
> a6xx_gmu_memory_free(gmu);
> err_put_device:
> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.h b/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
> index e034935b3986..5a42dd4dd31f 100644
> --- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
> @@ -56,6 +56,7 @@ struct a6xx_gmu {
> int gmu_irq;
>
> struct device *gxpd;
> + struct device *cxpd;
>
> int idle_level;
>
> --
> 2.7.4
>
