Thierry Reding <thierry.red...@gmail.com> writes: > * PGP Signed by an unknown key > > On Fri, Jun 27, 2014 at 03:41:20PM +0800, Joseph Lo wrote: >> Hi Thierry, >> >> On 06/27/2014 04:49 AM, Thierry Reding wrote: >> [snip] >> >+ >> >+#define MC_INTSTATUS 0x000 >> >+#define MC_INT_DECERR_MTS (1 << 16) >> >+#define MC_INT_SECERR_SEC (1 << 13) >> >+#define MC_INT_DECERR_VPR (1 << 12) >> >+#define MC_INT_INVALID_APB_ASID_UPDATE (1 << 11) >> >+#define MC_INT_INVALID_SMMU_PAGE (1 << 10) >> >+#define MC_INT_ARBITRATION_EMEM (1 << 9) >> >+#define MC_INT_SECURITY_VIOLATION (1 << 8) >> >+#define MC_INT_DECERR_EMEM (1 << 6) >> >+#define MC_INTMASK 0x004 >> >+#define MC_ERR_STATUS 0x08 >> >+#define MC_ERR_ADR 0x0c >> >+ >> [snip] >> >+ >> >+#define SMMU_PDE_ATTR (SMMU_PDE_READABLE | SMMU_PDE_WRITABLE | \ >> >+ SMMU_PDE_NONSECURE) >> >+#define SMMU_PTE_ATTR (SMMU_PTE_READABLE | SMMU_PTE_WRITABLE | \ >> >+ SMMU_PTE_NONSECURE) >> >+ >> >+#define SMMU_PDE_VACANT(n) (((n) << 10) | SMMU_PDE_ATTR) >> >+#define SMMU_PTE_VACANT(n) (((n) << 12) | SMMU_PTE_ATTR)
They should be set 0. The above VACANT macros are legacy support for some special case that a device wanted linear SMMU mapping where iova == phy. No need any more. >> There is an ISR to catch the invalid SMMU translation. Do you want to modify >> the identity mapping with read/write attribute of the unused SMMU pages? > > I'm not sure I understand what you mean by "identity mapping". None of > the public documentation seems to describe the exact layout of PDEs or > PTEs, so it's somewhat hard to tell what to set them to when pages are > unmapped. > >> This can make sure we capture the invalid SMMU translation. And helps for >> driver to capture issues when using SMMU. > > That certainly sounds like a useful thing to have. Like I said this is > an RFC and I'm not even sure if it's acceptable in the current form, so > I wanted to get feedback early on to avoid wasting effort on something > that turn out to be a wild-goose chase. > > Thierry > > * Unknown Key > * 0x7F3EB3A1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
