linux/include/asm-powerpc/pgtable-64k.h
Paul Mackerras c0f7c6cb5d [POWERPC] Expand RPN field to 34 bits when using 64k pages
The real page number field in our PTEs when configured for 64kB pages
is currently 32 bits, which turns out to be not quite enough for the
resources that the eHCA driver wants to map.  This expands the RPN
field to include 2 adjacent, previously-unused bits.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2007-08-03 14:08:24 +10:00

101 lines
3.9 KiB
C

#ifndef _ASM_POWERPC_PGTABLE_64K_H
#define _ASM_POWERPC_PGTABLE_64K_H
#include <asm-generic/pgtable-nopud.h>
#define PTE_INDEX_SIZE 12
#define PMD_INDEX_SIZE 12
#define PUD_INDEX_SIZE 0
#define PGD_INDEX_SIZE 4
#define PTE_TABLE_SIZE (sizeof(real_pte_t) << PTE_INDEX_SIZE)
#define PMD_TABLE_SIZE (sizeof(pmd_t) << PMD_INDEX_SIZE)
#define PGD_TABLE_SIZE (sizeof(pgd_t) << PGD_INDEX_SIZE)
#define PTRS_PER_PTE (1 << PTE_INDEX_SIZE)
#define PTRS_PER_PMD (1 << PMD_INDEX_SIZE)
#define PTRS_PER_PGD (1 << PGD_INDEX_SIZE)
/* With 4k base page size, hugepage PTEs go at the PMD level */
#define MIN_HUGEPTE_SHIFT PAGE_SHIFT
/* PMD_SHIFT determines what a second-level page table entry can map */
#define PMD_SHIFT (PAGE_SHIFT + PTE_INDEX_SIZE)
#define PMD_SIZE (1UL << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
/* PGDIR_SHIFT determines what a third-level page table entry can map */
#define PGDIR_SHIFT (PMD_SHIFT + PMD_INDEX_SIZE)
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
/* Additional PTE bits (don't change without checking asm in hash_low.S) */
#define _PAGE_HPTE_SUB 0x0ffff000 /* combo only: sub pages HPTE bits */
#define _PAGE_HPTE_SUB0 0x08000000 /* combo only: first sub page */
#define _PAGE_COMBO 0x10000000 /* this is a combo 4k page */
#define _PAGE_4K_PFN 0x20000000 /* PFN is for a single 4k page */
/* Note the full page bits must be in the same location as for normal
* 4k pages as the same asssembly will be used to insert 64K pages
* wether the kernel has CONFIG_PPC_64K_PAGES or not
*/
#define _PAGE_F_SECOND 0x00008000 /* full page: hidx bits */
#define _PAGE_F_GIX 0x00007000 /* full page: hidx bits */
/* PTE flags to conserve for HPTE identification */
#define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | _PAGE_HPTE_SUB |\
_PAGE_COMBO)
/* Shift to put page number into pte.
*
* That gives us a max RPN of 34 bits, which means a max of 50 bits
* of addressable physical space, or 46 bits for the special 4k PFNs.
*/
#define PTE_RPN_SHIFT (30)
#define PTE_RPN_MAX (1UL << (64 - PTE_RPN_SHIFT))
#define PTE_RPN_MASK (~((1UL<<PTE_RPN_SHIFT)-1))
/* _PAGE_CHG_MASK masks of bits that are to be preserved accross
* pgprot changes
*/
#define _PAGE_CHG_MASK (PTE_RPN_MASK | _PAGE_HPTEFLAGS | _PAGE_DIRTY | \
_PAGE_ACCESSED)
/* Bits to mask out from a PMD to get to the PTE page */
#define PMD_MASKED_BITS 0x1ff
/* Bits to mask out from a PGD/PUD to get to the PMD page */
#define PUD_MASKED_BITS 0x1ff
/* Manipulate "rpte" values */
#define __real_pte(e,p) ((real_pte_t) { \
(e), pte_val(*((p) + PTRS_PER_PTE)) })
#define __rpte_to_hidx(r,index) ((pte_val((r).pte) & _PAGE_COMBO) ? \
(((r).hidx >> ((index)<<2)) & 0xf) : ((pte_val((r).pte) >> 12) & 0xf))
#define __rpte_to_pte(r) ((r).pte)
#define __rpte_sub_valid(rpte, index) \
(pte_val(rpte.pte) & (_PAGE_HPTE_SUB0 >> (index)))
/* Trick: we set __end to va + 64k, which happens works for
* a 16M page as well as we want only one iteration
*/
#define pte_iterate_hashed_subpages(rpte, psize, va, index, shift) \
do { \
unsigned long __end = va + PAGE_SIZE; \
unsigned __split = (psize == MMU_PAGE_4K || \
psize == MMU_PAGE_64K_AP); \
shift = mmu_psize_defs[psize].shift; \
for (index = 0; va < __end; index++, va += (1 << shift)) { \
if (!__split || __rpte_sub_valid(rpte, index)) do { \
#define pte_iterate_hashed_end() } while(0); } } while(0)
#define pte_pagesize_index(mm, addr, pte) \
(((pte) & _PAGE_COMBO)? MMU_PAGE_4K: MMU_PAGE_64K)
#define remap_4k_pfn(vma, addr, pfn, prot) \
remap_pfn_range((vma), (addr), (pfn), PAGE_SIZE, \
__pgprot(pgprot_val((prot)) | _PAGE_4K_PFN))
#endif /* _ASM_POWERPC_PGTABLE_64K_H */