Re: [PATCH v6 6/6] iommu/tegra-smmu: Add pagetable mappings to debugfs

From: Nicolin Chen
Date: Tue Sep 14 2021 - 14:57:31 EST


On Tue, Sep 14, 2021 at 04:29:15PM +0300, Dmitry Osipenko wrote:
> 14.09.2021 04:38, Nicolin Chen пишет:
> > +static unsigned long pd_pt_index_iova(unsigned int pd_index, unsigned int pt_index)
> > +{
> > + return ((dma_addr_t)pd_index & (SMMU_NUM_PDE - 1)) << SMMU_PDE_SHIFT |
> > + ((dma_addr_t)pt_index & (SMMU_NUM_PTE - 1)) << SMMU_PTE_SHIFT;
> > +}
>
> We know that IOVA is fixed to u32 for this controller. Can we avoid all
> these dma_addr_t castings? It should make code cleaner a tad, IMO.

Tegra210 actually supports 34-bit IOVA...