pgtable_mm.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef _M68K_PGTABLE_H
  3#define _M68K_PGTABLE_H
  4
  5
  6#if defined(CONFIG_SUN3) || defined(CONFIG_COLDFIRE)
  7#include <asm-generic/pgtable-nopmd.h>
  8#else
  9#include <asm-generic/pgtable-nopud.h>
 10#endif
 11
 12#include <asm/setup.h>
 13
 14#ifndef __ASSEMBLER__
 15#include <asm/processor.h>
 16#include <linux/sched.h>
 17#include <linux/threads.h>
 18
 19/*
 20 * This file contains the functions and defines necessary to modify and use
 21 * the m68k page table tree.
 22 */
 23
 24#include <asm/virtconvert.h>
 25
 26/* Certain architectures need to do special things when pte's
 27 * within a page table are directly modified.  Thus, the following
 28 * hook is made available.
 29 */
 30#define set_pte(pteptr, pteval)					\
 31	do{							\
 32		*(pteptr) = (pteval);				\
 33	} while(0)
 34
 35/* PMD_SHIFT determines the size of the area a second-level page table can map */
 36#if CONFIG_PGTABLE_LEVELS == 3
 37#define PMD_SHIFT	18
 38#endif
 39#define PMD_SIZE	(1UL << PMD_SHIFT)
 40#define PMD_MASK	(~(PMD_SIZE-1))
 41
 42/* PGDIR_SHIFT determines what a third-level page table entry can map */
 43#ifdef CONFIG_SUN3
 44#define PGDIR_SHIFT     17
 45#elif defined(CONFIG_COLDFIRE)
 46#define PGDIR_SHIFT     22
 47#else
 48#define PGDIR_SHIFT	25
 49#endif
 50#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
 51#define PGDIR_MASK	(~(PGDIR_SIZE-1))
 52
 53/*
 54 * entries per page directory level: the m68k is configured as three-level,
 55 * so we do have PMD level physically.
 56 */
 57#ifdef CONFIG_SUN3
 58#define PTRS_PER_PTE   16
 59#define __PAGETABLE_PMD_FOLDED 1
 60#define PTRS_PER_PMD   1
 61#define PTRS_PER_PGD   2048
 62#elif defined(CONFIG_COLDFIRE)
 63#define PTRS_PER_PTE	512
 64#define __PAGETABLE_PMD_FOLDED 1
 65#define PTRS_PER_PMD	1
 66#define PTRS_PER_PGD	1024
 67#else
 68#define PTRS_PER_PTE	64
 69#define PTRS_PER_PMD	128
 70#define PTRS_PER_PGD	128
 71#endif
 72#define USER_PTRS_PER_PGD	(TASK_SIZE/PGDIR_SIZE)
 73
 74/* Virtual address region for use by kernel_map() */
 75#ifdef CONFIG_SUN3
 76#define KMAP_START	0x0dc00000
 77#define KMAP_END	0x0e000000
 78#elif defined(CONFIG_COLDFIRE)
 79#define KMAP_START	0xe0000000
 80#define KMAP_END	0xf0000000
 81#elif defined(CONFIG_VIRT)
 82#define	KMAP_START	0xdf000000
 83#define	KMAP_END	0xff000000
 84#else
 85#define	KMAP_START	0xd0000000
 86#define	KMAP_END	0xf0000000
 87#endif
 88
 89#ifdef CONFIG_SUN3
 90extern unsigned long m68k_vmalloc_end;
 91#define VMALLOC_START 0x0f800000
 92#define VMALLOC_END m68k_vmalloc_end
 93#elif defined(CONFIG_COLDFIRE)
 94#define VMALLOC_START	0xd0000000
 95#define VMALLOC_END	0xe0000000
 96#elif defined(CONFIG_VIRT)
 97#define VMALLOC_OFFSET	PAGE_SIZE
 98#define VMALLOC_START (((unsigned long) high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
 99#define VMALLOC_END     KMAP_START
100#else
101/* Just any arbitrary offset to the start of the vmalloc VM area: the
102 * current 8MB value just means that there will be a 8MB "hole" after the
103 * physical memory until the kernel virtual memory starts.  That means that
104 * any out-of-bounds memory accesses will hopefully be caught.
105 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
106 * area for the same reason. ;)
107 */
108#define VMALLOC_OFFSET	(8*1024*1024)
109#define VMALLOC_START (((unsigned long) high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
110#define VMALLOC_END KMAP_START
111#endif
112
113/* zero page used for uninitialized stuff */
114extern void *empty_zero_page;
115
116/*
117 * ZERO_PAGE is a global shared page that is always zero: used
118 * for zero-mapped memory areas etc..
119 */
120#define ZERO_PAGE(vaddr)	(virt_to_page(empty_zero_page))
121
122extern void kernel_set_cachemode(void *addr, unsigned long size, int cmode);
123
124/*
125 * The m68k doesn't have any external MMU info: the kernel page
126 * tables contain all the necessary information.  The Sun3 does, but
127 * they are updated on demand.
128 */
129static inline void update_mmu_cache_range(struct vm_fault *vmf,
130		struct vm_area_struct *vma, unsigned long address,
131		pte_t *ptep, unsigned int nr)
132{
133}
134
135#define update_mmu_cache(vma, addr, ptep) \
136	update_mmu_cache_range(NULL, vma, addr, ptep, 1)
137
138#endif /* !__ASSEMBLER__ */
139
140/* MMU-specific headers */
141
142#ifdef CONFIG_SUN3
143#include <asm/sun3_pgtable.h>
144#elif defined(CONFIG_COLDFIRE)
145#include <asm/mcf_pgtable.h>
146#else
147#include <asm/motorola_pgtable.h>
148#endif
149
150#ifndef __ASSEMBLER__
151/*
152 * Macro to mark a page protection value as "uncacheable".
153 */
154#ifdef CONFIG_COLDFIRE
155# define pgprot_noncached(prot) (__pgprot(pgprot_val(prot) | CF_PAGE_NOCACHE))
156#else
157#ifdef SUN3_PAGE_NOCACHE
158# define __SUN3_PAGE_NOCACHE	SUN3_PAGE_NOCACHE
159#else
160# define __SUN3_PAGE_NOCACHE	0
161#endif
162#define pgprot_noncached(prot)							\
163	(MMU_IS_SUN3								\
164	 ? (__pgprot(pgprot_val(prot) | __SUN3_PAGE_NOCACHE))			\
165	 : ((MMU_IS_851 || MMU_IS_030)						\
166	    ? (__pgprot(pgprot_val(prot) | _PAGE_NOCACHE030))			\
167	    : (MMU_IS_040 || MMU_IS_060)					\
168	    ? (__pgprot((pgprot_val(prot) & _CACHEMASK040) | _PAGE_NOCACHE_S))	\
169	    : (prot)))
170
171pgprot_t pgprot_dmacoherent(pgprot_t prot);
172#define pgprot_dmacoherent(prot)	pgprot_dmacoherent(prot)
173
174#endif /* CONFIG_COLDFIRE */
175#endif /* !__ASSEMBLER__ */
176
177#endif /* _M68K_PGTABLE_H */