Re: [PATCH v1 1/3] drm/msm: Attach the IOMMU device during initialization

Rob Clark
2020-05-23T23:18:45Z

On Sat, May 23, 2020 at 12:23 AM Shawn Guo <shawn.guo@linaro.org> wrote:
>
> On Fri, May 22, 2020 at 04:03:14PM -0600, Jordan Crouse wrote:
> > diff --git a/drivers/gpu/drm/msm/msm_gpummu.c b/drivers/gpu/drm/msm/msm_gpummu.c
> > index 34980d8eb7ad..0ad0f848560a 100644
> > --- a/drivers/gpu/drm/msm/msm_gpummu.c
> > +++ b/drivers/gpu/drm/msm/msm_gpummu.c
> > @@ -21,11 +21,6 @@ struct msm_gpummu {
> > #define GPUMMU_PAGE_SIZE SZ_4K
> > #define TABLE_SIZE (sizeof(uint32_t) * GPUMMU_VA_RANGE / GPUMMU_PAGE_SIZE)
> >
> > -static int msm_gpummu_attach(struct msm_mmu *mmu)
> > -{
> > - return 0;
> > -}
> > -
> > static void msm_gpummu_detach(struct msm_mmu *mmu)
> > {
> > }
> > @@ -85,7 +80,6 @@ static void msm_gpummu_destroy(struct msm_mmu *mmu)
> > }
> >
> > static const struct msm_mmu_funcs funcs = {
> > - .attach = msm_gpummu_attach,
> > .detach = msm_gpummu_detach,
> > .map = msm_gpummu_map,
> > .unmap = msm_gpummu_unmap,
> > diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c
> > index ad58cfe5998e..e35dab5792cf 100644
> > --- a/drivers/gpu/drm/msm/msm_iommu.c
> > +++ b/drivers/gpu/drm/msm/msm_iommu.c
> > @@ -66,7 +66,6 @@ static void msm_iommu_destroy(struct msm_mmu *mmu)
> > }
> >
> > static const struct msm_mmu_funcs funcs = {
> > - .attach = msm_iommu_attach,
>
> It causes an unused function warning as below.
>
> drivers/gpu/drm/msm/msm_iommu.c:26:12: warning: ‘msm_iommu_attach’ defined but not used [-Wunused-function]
> static int msm_iommu_attach(struct msm_mmu *mmu)
> ^~~~~~~~~~~~~~~~
>
> Not sure if you will use it again in future patches though.

looks like this was removed in msm_gpummu (a2xx) but not msm_iommu
(a3xx+).. I've squashed a fixup and pushed to msm-next

thx

BR,
-R

> Shawn
>
> > .detach = msm_iommu_detach,
> > .map = msm_iommu_map,
> > .unmap = msm_iommu_unmap,
> > @@ -76,6 +75,7 @@ static const struct msm_mmu_funcs funcs = {
> > struct msm_mmu *msm_iommu_new(struct device *dev, struct iommu_domain *domain)
> > {
> > struct msm_iommu *iommu;
> > + int ret;
> >
> > iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
> > if (!iommu)
> > @@ -85,5 +85,11 @@ struct msm_mmu *msm_iommu_new(struct device *dev, struct iommu_domain *domain)
> > msm_mmu_init(&iommu->base, dev, &funcs);
> > iommu_set_fault_handler(domain, msm_fault_handler, iommu);
> >
> > + ret = iommu_attach_device(iommu->domain, dev);
> > + if (ret) {
> > + kfree(iommu);
> > + return ERR_PTR(ret);
> > + }
> > +
> > return &iommu->base;
> > }
> > diff --git a/drivers/gpu/drm/msm/msm_mmu.h b/drivers/gpu/drm/msm/msm_mmu.h
> > index 67a623f14319..bae9e8e67ec1 100644
> > --- a/drivers/gpu/drm/msm/msm_mmu.h
> > +++ b/drivers/gpu/drm/msm/msm_mmu.h
> > @@ -10,7 +10,6 @@
> > #include <linux/iommu.h>
> >
> > struct msm_mmu_funcs {
> > - int (*attach)(struct msm_mmu *mmu);
> > void (*detach)(struct msm_mmu *mmu);
> > int (*map)(struct msm_mmu *mmu, uint64_t iova, struct sg_table *sgt,
> > unsigned len, int prot);
> > --
> > 2.17.1
> >