[PATCH 3/3] drm/msm/mdp4: use msm_kms_init_vm() instead of duplicating it

[Rob Clark]

On Sun, Jul 6, 2025 at 3:50 AM Dmitry Baryshkov
<dmitry.baryshkov at oss.qualcomm.com> wrote:
>
> Use the msm_kms_init_vm() function to allocate memory manager instead of
> hand-coding a copy of it. Although MDP4 platforms don't have MDSS
> device, it's still safe to use the function as all MDP4 devices have
> IOMMU and the parent of the MDP4 is the root SoC device.

So, originally the distinction was that mdp4 didn't have the mdss
wrapper.  Maybe it works out because device_iommu_mapped(mdp_dev)
returns true?

BR,
-R

> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at oss.qualcomm.com>
> ---
>  drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c | 27 +++++----------------------
>  1 file changed, 5 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
> index 88296c41d1a5eb0e16cb6ec4d0475000b6318c4e..41d236d30e71ebb6ac8a59052529f36fadf15cd7 100644
> --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
> +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
> @@ -391,11 +391,9 @@ static void read_mdp_hw_revision(struct mdp4_kms *mdp4_kms,
>
>  static int mdp4_kms_init(struct drm_device *dev)
>  {
> -       struct platform_device *pdev = to_platform_device(dev->dev);
>         struct msm_drm_private *priv = dev->dev_private;
>         struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(priv->kms));
>         struct msm_kms *kms = NULL;
> -       struct msm_mmu *mmu;
>         struct drm_gpuvm *vm;
>         int ret;
>         u32 major, minor;
> @@ -458,29 +456,14 @@ static int mdp4_kms_init(struct drm_device *dev)
>         mdp4_disable(mdp4_kms);
>         mdelay(16);
>
> -       mmu = msm_iommu_new(&pdev->dev, 0);
> -       if (IS_ERR(mmu)) {
> -               ret = PTR_ERR(mmu);
> +       vm = msm_kms_init_vm(mdp4_kms->dev);
> +       if (IS_ERR(vm)) {
> +               ret = PTR_ERR(vm);
>                 goto fail;
> -       } else if (!mmu) {
> -               DRM_DEV_INFO(dev->dev, "no IOMMU configuration is no longer supported\n");
> -               ret = -ENODEV;
> -               goto fail;
> -       } else {
> -               vm  = msm_gem_vm_create(dev, mmu, "mdp4",
> -                                       0x1000, 0x100000000 - 0x1000,
> -                                       true);
> -
> -               if (IS_ERR(vm)) {
> -                       if (!IS_ERR(mmu))
> -                               mmu->funcs->destroy(mmu);
> -                       ret = PTR_ERR(vm);
> -                       goto fail;
> -               }
> -
> -               kms->vm = vm;
>         }
>
> +       kms->vm = vm;
> +
>         ret = modeset_init(mdp4_kms);
>         if (ret) {
>                 DRM_DEV_ERROR(dev->dev, "modeset_init failed: %d\n", ret);
>
> --
> 2.39.5
>