From mboxrd@z Thu Jan 1 00:00:00 1970 From: david@gibson.dropbear.id.au (David Gibson) Date: Tue, 6 Oct 2015 14:19:43 +1100 Subject: [PATCH 1/2] powerpc/iommu: expose IOMMU page shift In-Reply-To: <20151002171800.GB41011@linux.vnet.ibm.com> References: <20151002171606.GA41011@linux.vnet.ibm.com> <20151002171800.GB41011@linux.vnet.ibm.com> Message-ID: <20151006031943.GC3861@voom.fritz.box> On Fri, Oct 02, 2015@10:18:00AM -0700, Nishanth Aravamudan wrote: > We will leverage this macro in the NVMe driver, which needs to know the > configured IOMMU page shift to properly configure its device's page > size. > > Signed-off-by: Nishanth Aravamudan > > --- > Given this is available, it seems reasonable to expose -- and it doesn't > really make sense to make the driver do a log2 call on the existing > IOMMU_PAGE_SIZE() value. > > diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h > index ca18cff..6fdf857 100644 > --- a/arch/powerpc/include/asm/iommu.h > +++ b/arch/powerpc/include/asm/iommu.h > @@ -36,6 +36,7 @@ > #define IOMMU_PAGE_MASK_4K (~((1 << IOMMU_PAGE_SHIFT_4K) - 1)) > #define IOMMU_PAGE_ALIGN_4K(addr) _ALIGN_UP(addr, IOMMU_PAGE_SIZE_4K) > > +#define IOMMU_PAGE_SHIFT(tblptr) (tblptr)->it_page_shift > #define IOMMU_PAGE_SIZE(tblptr) (ASM_CONST(1) << (tblptr)->it_page_shift) Seems like it would be a touch safer to alter IOMMU_PAGE_SIZE so it uses the new IOMMU_PAGE_SHIFT macro. > #define IOMMU_PAGE_MASK(tblptr) (~((1 << (tblptr)->it_page_shift) - 1)) > #define IOMMU_PAGE_ALIGN(addr, tblptr) _ALIGN_UP(addr, IOMMU_PAGE_SIZE(tblptr)) > -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: not available URL: