diff options
| author |   Ilya Yanok <yanok@emcraft.com> | 2008-12-11 04:55:41 +0300 |
|---|---|---|
| committer |   Paul Mackerras <paulus@samba.org> | 2008-12-29 09:53:25 +1100 |
| commit | ca9153a3a2a7556d091dfe080e42b0e67881fff6 (patch) | |
| tree | 35b5ce24f190690cf7a726cbb97980da51704855 /arch/powerpc/mm/pgtable_32.c | |
| parent | powerpc: Force memory size to be a multiple of PAGE_SIZE (diff) | |
| download | linux-dev-ca9153a3a2a7556d091dfe080e42b0e67881fff6.tar.xz linux-dev-ca9153a3a2a7556d091dfe080e42b0e67881fff6.zip | |
powerpc/44x: Support 16K/64K base page sizes on 44x
This adds support for 16k and 64k page sizes on PowerPC 44x processors.
The PGDIR table is much smaller than a page when using 16k or 64k
pages (512 and 32 bytes respectively) so we allocate the PGDIR with
kzalloc() instead of __get_free_pages().
One PTE table covers rather a large memory area when using 16k or 64k
pages (32MB or 512MB respectively), so we can easily put FIXMAP and
PKMAP in the area covered by one PTE table.
Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Vladimir Panfilov <pvr@emcraft.com>
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/mm/pgtable_32.c')
| -rw-r--r-- | arch/powerpc/mm/pgtable_32.c | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c index 8cba46fc9e3b..38ff35f2142a 100644 --- a/arch/powerpc/mm/pgtable_32.c +++ b/arch/powerpc/mm/pgtable_32.c @@ -68,24 +68,29 @@ extern unsigned long p_mapped_by_tlbcam(unsigned long pa); #define p_mapped_by_tlbcam(x) (0UL) #endif /* HAVE_TLBCAM */ -#ifdef CONFIG_PTE_64BIT -/* Some processors use an 8kB pgdir because they have 8-byte Linux PTEs. */ -#define PGDIR_ORDER 1 -#else -#define PGDIR_ORDER 0 -#endif +#define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT) pgd_t *pgd_alloc(struct mm_struct *mm) { pgd_t *ret; - ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, PGDIR_ORDER); + /* pgdir take page or two with 4K pages and a page fraction otherwise */ +#ifndef CONFIG_PPC_4K_PAGES + ret = (pgd_t *)kzalloc(1 << PGDIR_ORDER, GFP_KERNEL); +#else + ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, + PGDIR_ORDER - PAGE_SHIFT); +#endif return ret; } void pgd_free(struct mm_struct *mm, pgd_t *pgd) { - free_pages((unsigned long)pgd, PGDIR_ORDER); +#ifndef CONFIG_PPC_4K_PAGES + kfree((void *)pgd); +#else + free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT); +#endif } __init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) @@ -385,7 +390,7 @@ void kernel_map_pages(struct page *page, int numpages, int enable) #endif /* CONFIG_DEBUG_PAGEALLOC */ static int fixmaps; -unsigned long FIXADDR_TOP = 0xfffff000; +unsigned long FIXADDR_TOP = (-PAGE_SIZE); EXPORT_SYMBOL(FIXADDR_TOP); void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags) |