On Tue, 2016-02-09 at 18:52 +0530, Aneesh Kumar K.V wrote: > > Hi Scott, > > I missed adding you on CC:, Can you take a look at this and make sure we > are not breaking anything on freescale. I'm having trouble getting it to apply cleanly. Do you have a git tree I can test? -Scott > "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxxxxxxx> writes: > > > Hello, > > > > This is a large series, mostly consisting of code movement. No new > > features > > are done in this series. The changes are done to accomodate the upcoming > > new memory > > model in future powerpc chips. The details of the new MMU model can be > > found at > > > > http://ibm.biz/power-isa3 (Needs registration). I am including a summary > > of the changes below. > > > > ISA 3.0 adds support for the radix tree style of MMU with full > > virtualization and related control mechanisms that manage its > > coexistence with the HPT. Radix-using operating systems will > > manage their own translation tables instead of relying on hcalls. > > > > Radix style MMU model requires us to do a 4 level page table > > with 64K and 4K page size. The table index size different page size > > is listed below > > > > PGD -> 13 bits > > PUD -> 9 (1G hugepage) > > PMD -> 9 (2M huge page) > > PTE -> 5 (for 64k), 9 (for 4k) > > > > We also require the page table to be in big endian format. > > > > The changes proposed in this series enables us to support both > > hash page table and radix tree style MMU using a single kernel > > with limited impact. The idea is to change core page table > > accessors to static inline functions and later hotpatch them > > to switch to hash or radix tree functions. For ex: > > > > static inline int pte_write(pte_t pte) > > { > > if (radix_enabled()) > > return rpte_write(pte); > > return hlpte_write(pte); > > } > > > > On boot we will hotpatch the code so as to avoid conditional operation. > > > > The other two major change propsed in this series is to switch hash > > linux page table to a 4 level table in big endian format. This is > > done so that functions like pte_val(), pud_populate() doesn't need > > hotpatching and thereby helps in limiting runtime impact of the changes. > > > > I didn't included the radix related changes in this series. You can > > find them at https://github.com/kvaneesh/linux/commits/radix-mmu-v1 > > > > Changes from V1: > > * move patches adding helpers to the next series > > > > > Thanks > -aneesh > > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@xxxxxxxxxxxxxxxx > https://lists.ozlabs.org/listinfo/linuxppc-dev -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>