On Thu, 5 May 2022 at 13:27, Robin Murphy <robin.murphy@xxxxxxx> wrote:
>
> On 2022-05-05 01:16, Dmitry Baryshkov wrote:
> > Change msm_kms_init_aspace() to use generic function
> > device_iommu_mapped() instead of the fwnode-specific interface
> > dev_iommu_fwspec_get(). While we are at it, stop referencing
> > platform_bus_type directly and use the bus of the IOMMU device.
>
> FWIW, I'd have squashed these changes across the previous patches, such
> that the dodgy fwspec calls are never introduced in the first place, but
> it's your driver, and if that's the way you want to work it and Rob's
> happy with it too, then fine by me.
I thought about this. But as the calls were already there (in the
mdp5), it was easier for me to merge the code and to update it
afterwards.
>
> For the end result,
>
> Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx>
>
> I'm guessing MDP4 could probably use msm_kms_init_aspace() now as well,
> but unless there's any other reason to respin this series, that's
> something we could do as a follow-up. Thanks for sorting this out!
Not really. MDP4 doesn't have the parent MDSS device, so it doesn't
need all these troubles.
>
> Robin.
>
> > Suggested-by: Robin Murphy <robin.murphy@xxxxxxx>
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> > ---
> > drivers/gpu/drm/msm/msm_drv.c | 14 +++++++-------
> > 1 file changed, 7 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
> > index 98ae0036ab57..2fc3f820cd59 100644
> > --- a/drivers/gpu/drm/msm/msm_drv.c
> > +++ b/drivers/gpu/drm/msm/msm_drv.c
> > @@ -272,21 +272,21 @@ struct msm_gem_address_space *msm_kms_init_aspace(struct drm_device *dev)
> > struct device *mdss_dev = mdp_dev->parent;
> > struct device *iommu_dev;
> >
> > - domain = iommu_domain_alloc(&platform_bus_type);
> > - if (!domain) {
> > - drm_info(dev, "no IOMMU, fallback to phys contig buffers for scanout\n");
> > - return NULL;
> > - }
> > -
> > /*
> > * IOMMUs can be a part of MDSS device tree binding, or the
> > * MDP/DPU device.
> > */
> > - if (dev_iommu_fwspec_get(mdp_dev))
> > + if (device_iommu_mapped(mdp_dev))
> > iommu_dev = mdp_dev;
> > else
> > iommu_dev = mdss_dev;
> >
> > + domain = iommu_domain_alloc(iommu_dev->bus);
> > + if (!domain) {
> > + drm_info(dev, "no IOMMU, fallback to phys contig buffers for scanout\n");
> > + return NULL;
> > + }
> > +
> > mmu = msm_iommu_new(iommu_dev, domain);
> > if (IS_ERR(mmu)) {
> > iommu_domain_free(domain);
--
With best wishes
Dmitry
