linux/arch/sh/include/asm/page.h
Paul Mundt d01447b319 sh: Merge legacy and dynamic PMB modes.
This implements a bit of rework for the PMB code, which permits us to
kill off the legacy PMB mode completely. Rather than trusting the boot
loader to do the right thing, we do a quick verification of the PMB
contents to determine whether to have the kernel setup the initial
mappings or whether it needs to mangle them later on instead.

If we're booting from legacy mappings, the kernel will now take control
of them and make them match the kernel's initial mapping configuration.
This is accomplished by breaking the initialization phase out in to
multiple steps: synchronization, merging, and resizing. With the recent
rework, the synchronization code establishes page links for compound
mappings already, so we build on top of this for promoting mappings and
reclaiming unused slots.

At the same time, the changes introduced for the uncached helpers also
permit us to dynamically resize the uncached mapping without any
particular headaches. The smallest page size is more than sufficient for
mapping all of kernel text, and as we're careful not to jump to any far
off locations in the setup code the mapping can safely be resized
regardless of whether we are executing from it or not.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2010-02-18 18:13:51 +09:00

191 lines
5.6 KiB
C

#ifndef __ASM_SH_PAGE_H
#define __ASM_SH_PAGE_H
/*
* Copyright (C) 1999 Niibe Yutaka
*/
#include <linux/const.h>
/* PAGE_SHIFT determines the page size */
#if defined(CONFIG_PAGE_SIZE_4KB)
# define PAGE_SHIFT 12
#elif defined(CONFIG_PAGE_SIZE_8KB)
# define PAGE_SHIFT 13
#elif defined(CONFIG_PAGE_SIZE_16KB)
# define PAGE_SHIFT 14
#elif defined(CONFIG_PAGE_SIZE_64KB)
# define PAGE_SHIFT 16
#else
# error "Bogus kernel page size?"
#endif
#define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE-1))
#define PTE_MASK PAGE_MASK
#if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
#define HPAGE_SHIFT 16
#elif defined(CONFIG_HUGETLB_PAGE_SIZE_256K)
#define HPAGE_SHIFT 18
#elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
#define HPAGE_SHIFT 20
#elif defined(CONFIG_HUGETLB_PAGE_SIZE_4MB)
#define HPAGE_SHIFT 22
#elif defined(CONFIG_HUGETLB_PAGE_SIZE_64MB)
#define HPAGE_SHIFT 26
#elif defined(CONFIG_HUGETLB_PAGE_SIZE_512MB)
#define HPAGE_SHIFT 29
#endif
#ifdef CONFIG_HUGETLB_PAGE
#define HPAGE_SIZE (1UL << HPAGE_SHIFT)
#define HPAGE_MASK (~(HPAGE_SIZE-1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT-PAGE_SHIFT)
#endif
#ifndef __ASSEMBLY__
#include <asm/uncached.h>
extern unsigned long shm_align_mask;
extern unsigned long max_low_pfn, min_low_pfn;
extern unsigned long memory_start, memory_end;
static inline unsigned long
pages_do_alias(unsigned long addr1, unsigned long addr2)
{
return (addr1 ^ addr2) & shm_align_mask;
}
#define clear_page(page) memset((void *)(page), 0, PAGE_SIZE)
extern void copy_page(void *to, void *from);
struct page;
struct vm_area_struct;
extern void copy_user_highpage(struct page *to, struct page *from,
unsigned long vaddr, struct vm_area_struct *vma);
#define __HAVE_ARCH_COPY_USER_HIGHPAGE
extern void clear_user_highpage(struct page *page, unsigned long vaddr);
#define clear_user_highpage clear_user_highpage
/*
* These are used to make use of C type-checking..
*/
#ifdef CONFIG_X2TLB
typedef struct { unsigned long pte_low, pte_high; } pte_t;
typedef struct { unsigned long long pgprot; } pgprot_t;
typedef struct { unsigned long long pgd; } pgd_t;
#define pte_val(x) \
((x).pte_low | ((unsigned long long)(x).pte_high << 32))
#define __pte(x) \
({ pte_t __pte = {(x), ((unsigned long long)(x)) >> 32}; __pte; })
#elif defined(CONFIG_SUPERH32)
typedef struct { unsigned long pte_low; } pte_t;
typedef struct { unsigned long pgprot; } pgprot_t;
typedef struct { unsigned long pgd; } pgd_t;
#define pte_val(x) ((x).pte_low)
#define __pte(x) ((pte_t) { (x) } )
#else
typedef struct { unsigned long long pte_low; } pte_t;
typedef struct { unsigned long long pgprot; } pgprot_t;
typedef struct { unsigned long pgd; } pgd_t;
#define pte_val(x) ((x).pte_low)
#define __pte(x) ((pte_t) { (x) } )
#endif
#define pgd_val(x) ((x).pgd)
#define pgprot_val(x) ((x).pgprot)
#define __pgd(x) ((pgd_t) { (x) } )
#define __pgprot(x) ((pgprot_t) { (x) } )
typedef struct page *pgtable_t;
#define pte_pgprot(x) __pgprot(pte_val(x) & PTE_FLAGS_MASK)
#endif /* !__ASSEMBLY__ */
/*
* __MEMORY_START and SIZE are the physical addresses and size of RAM.
*/
#define __MEMORY_START CONFIG_MEMORY_START
#define __MEMORY_SIZE CONFIG_MEMORY_SIZE
/*
* PAGE_OFFSET is the virtual address of the start of kernel address
* space.
*/
#define PAGE_OFFSET CONFIG_PAGE_OFFSET
/*
* Virtual to physical RAM address translation.
*
* In 29 bit mode, the physical offset of RAM from address 0 is visible in
* the kernel virtual address space, and thus we don't have to take
* this into account when translating. However in 32 bit mode this offset
* is not visible (it is part of the PMB mapping) and so needs to be
* added or subtracted as required.
*/
#ifdef CONFIG_PMB
#define __pa(x) ((unsigned long)(x)-PAGE_OFFSET+__MEMORY_START)
#define __va(x) ((void *)((unsigned long)(x)+PAGE_OFFSET-__MEMORY_START))
#else
#define __pa(x) ((unsigned long)(x)-PAGE_OFFSET)
#define __va(x) ((void *)((unsigned long)(x)+PAGE_OFFSET))
#endif
#ifdef CONFIG_UNCACHED_MAPPING
#define UNCAC_ADDR(addr) ((addr) - PAGE_OFFSET + uncached_start)
#define CAC_ADDR(addr) ((addr) - uncached_start + PAGE_OFFSET)
#else
#define UNCAC_ADDR(addr) ((addr))
#define CAC_ADDR(addr) ((addr))
#endif
#define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
/*
* PFN = physical frame number (ie PFN 0 == physical address 0)
* PFN_START is the PFN of the first page of RAM. By defining this we
* don't have struct page entries for the portion of address space
* between physical address 0 and the start of RAM.
*/
#define PFN_START (__MEMORY_START >> PAGE_SHIFT)
#define ARCH_PFN_OFFSET (PFN_START)
#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
#ifdef CONFIG_FLATMEM
#define pfn_valid(pfn) ((pfn) >= min_low_pfn && (pfn) < max_low_pfn)
#endif
#define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
#define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | VM_EXEC | \
VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
#include <asm-generic/memory_model.h>
#include <asm-generic/getorder.h>
/* vDSO support */
#ifdef CONFIG_VSYSCALL
#define __HAVE_ARCH_GATE_AREA
#endif
/*
* Some drivers need to perform DMA into kmalloc'ed buffers
* and so we have to increase the kmalloc minalign for this.
*/
#define ARCH_KMALLOC_MINALIGN L1_CACHE_BYTES
#ifdef CONFIG_SUPERH64
/*
* While BYTES_PER_WORD == 4 on the current sh64 ABI, GCC will still
* happily generate {ld/st}.q pairs, requiring us to have 8-byte
* alignment to avoid traps. The kmalloc alignment is gauranteed by
* virtue of L1_CACHE_BYTES, requiring this to only be special cased
* for slab caches.
*/
#define ARCH_SLAB_MINALIGN 8
#endif
#endif /* __ASM_SH_PAGE_H */