diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-03-30 10:23:53 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-03-30 10:23:53 -0700 |
commit | ebc8eca169be0283d5a7ab54c4411dd59cfb0f27 (patch) | |
tree | 831f6d577da3469e3154bf29409281c640bb67df /arch/powerpc/include/asm/pte-40x.h | |
parent | 25c1a411e8a0a709abe3449866125dc290711ea8 (diff) | |
parent | 9ff9a26b786c35ee8d2a66222924a807ec851a9f (diff) |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (180 commits)
powerpc: clean up ssi.txt, add definition for fsl,ssi-asynchronous
powerpc/85xx: Add support for the "socrates" board (MPC8544).
powerpc: Fix bugs introduced by sysfs changes
powerpc: Sanitize stack pointer in signal handling code
powerpc: Add write barrier before enabling DTL flags
powerpc/83xx: Update ranges in gianfar node to match other dts
powerpc/86xx: Move gianfar mdio nodes under the ethernet nodes
powerpc/85xx: Move gianfar mdio nodes under the ethernet nodes
powerpc/83xx: Move gianfar mdio nodes under the ethernet nodes
powerpc/83xx: Add power management support for MPC837x boards
powerpc/mm: Introduce early_init_mmu() on 64-bit
powerpc/mm: Add option for non-atomic PTE updates to ppc64
powerpc/mm: Fix printk type warning in mmu_context_nohash
powerpc/mm: Rename arch/powerpc/kernel/mmap.c to mmap_64.c
powerpc/mm: Merge various PTE bits and accessors definitions
powerpc/mm: Tweak PTE bit combination definitions
powerpc/cell: Fix iommu exception reporting
powerpc/mm: e300c2/c3/c4 TLB errata workaround
powerpc/mm: Used free register to save a few cycles in SW TLB miss handling
powerpc/mm: Remove unused register usage in SW TLB miss handling
...
Diffstat (limited to 'arch/powerpc/include/asm/pte-40x.h')
-rw-r--r-- | arch/powerpc/include/asm/pte-40x.h | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/pte-40x.h b/arch/powerpc/include/asm/pte-40x.h new file mode 100644 index 00000000000..07630faae02 --- /dev/null +++ b/arch/powerpc/include/asm/pte-40x.h @@ -0,0 +1,64 @@ +#ifndef _ASM_POWERPC_PTE_40x_H +#define _ASM_POWERPC_PTE_40x_H +#ifdef __KERNEL__ + +/* + * At present, all PowerPC 400-class processors share a similar TLB + * architecture. The instruction and data sides share a unified, + * 64-entry, fully-associative TLB which is maintained totally under + * software control. In addition, the instruction side has a + * hardware-managed, 4-entry, fully-associative TLB which serves as a + * first level to the shared TLB. These two TLBs are known as the UTLB + * and ITLB, respectively (see "mmu.h" for definitions). + * + * There are several potential gotchas here. The 40x hardware TLBLO + * field looks like this: + * + * 0 1 2 3 4 ... 18 19 20 21 22 23 24 25 26 27 28 29 30 31 + * RPN..................... 0 0 EX WR ZSEL....... W I M G + * + * Where possible we make the Linux PTE bits match up with this + * + * - bits 20 and 21 must be cleared, because we use 4k pages (40x can + * support down to 1k pages), this is done in the TLBMiss exception + * handler. + * - We use only zones 0 (for kernel pages) and 1 (for user pages) + * of the 16 available. Bit 24-26 of the TLB are cleared in the TLB + * miss handler. Bit 27 is PAGE_USER, thus selecting the correct + * zone. + * - PRESENT *must* be in the bottom two bits because swap cache + * entries use the top 30 bits. Because 40x doesn't support SMP + * anyway, M is irrelevant so we borrow it for PAGE_PRESENT. Bit 30 + * is cleared in the TLB miss handler before the TLB entry is loaded. + * - All other bits of the PTE are loaded into TLBLO without + * modification, leaving us only the bits 20, 21, 24, 25, 26, 30 for + * software PTE bits. We actually use use bits 21, 24, 25, and + * 30 respectively for the software bits: ACCESSED, DIRTY, RW, and + * PRESENT. + */ + +#define _PAGE_GUARDED 0x001 /* G: page is guarded from prefetch */ +#define _PAGE_FILE 0x001 /* when !present: nonlinear file mapping */ +#define _PAGE_PRESENT 0x002 /* software: PTE contains a translation */ +#define _PAGE_NO_CACHE 0x004 /* I: caching is inhibited */ +#define _PAGE_WRITETHRU 0x008 /* W: caching is write-through */ +#define _PAGE_USER 0x010 /* matches one of the zone permission bits */ +#define _PAGE_RW 0x040 /* software: Writes permitted */ +#define _PAGE_DIRTY 0x080 /* software: dirty page */ +#define _PAGE_HWWRITE 0x100 /* hardware: Dirty & RW, set in exception */ +#define _PAGE_HWEXEC 0x200 /* hardware: EX permission */ +#define _PAGE_ACCESSED 0x400 /* software: R: page referenced */ + +#define _PMD_PRESENT 0x400 /* PMD points to page of PTEs */ +#define _PMD_BAD 0x802 +#define _PMD_SIZE 0x0e0 /* size field, != 0 for large-page PMD entry */ +#define _PMD_SIZE_4M 0x0c0 +#define _PMD_SIZE_16M 0x0e0 + +#define PMD_PAGE_SIZE(pmdval) (1024 << (((pmdval) & _PMD_SIZE) >> 4)) + +/* Until my rework is finished, 40x still needs atomic PTE updates */ +#define PTE_ATOMIC_UPDATES 1 + +#endif /* __KERNEL__ */ +#endif /* _ASM_POWERPC_PTE_40x_H */ |