1/* SPDX-License-Identifier: GPL-2.0
2 *
3 * This file contains the functions and defines necessary to modify and
4 * use the SuperH page table tree.
5 *
6 * Copyright (C) 1999 Niibe Yutaka
7 * Copyright (C) 2002 - 2007 Paul Mundt
8 */
9#ifndef __ASM_SH_PGTABLE_H
10#define __ASM_SH_PGTABLE_H
11
12#ifdef CONFIG_X2TLB
13#include <asm/pgtable-3level.h>
14#else
15#include <asm/pgtable-2level.h>
16#endif
17#include <asm/page.h>
18#include <asm/mmu.h>
19
20#ifndef __ASSEMBLY__
21#include <asm/addrspace.h>
22#include <asm/fixmap.h>
23
24/*
25 * ZERO_PAGE is a global shared page that is always zero: used
26 * for zero-mapped memory areas etc..
27 */
28extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
29#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
30
31#endif /* !__ASSEMBLY__ */
32
33/*
34 * Effective and physical address definitions, to aid with sign
35 * extension.
36 */
37#define NEFF		32
38#define	NEFF_SIGN	(1LL << (NEFF - 1))
39#define	NEFF_MASK	(-1LL << NEFF)
40
41static inline unsigned long long neff_sign_extend(unsigned long val)
42{
43	unsigned long long extended = val;
44	return (extended & NEFF_SIGN) ? (extended | NEFF_MASK) : extended;
45}
46
47#ifdef CONFIG_29BIT
48#define NPHYS		29
49#else
50#define NPHYS		32
51#endif
52
53#define	NPHYS_SIGN	(1LL << (NPHYS - 1))
54#define	NPHYS_MASK	(-1LL << NPHYS)
55
56#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
57#define PGDIR_MASK	(~(PGDIR_SIZE-1))
58
59/* Entries per level */
60#define PTRS_PER_PTE	(PAGE_SIZE / (1 << PTE_MAGNITUDE))
61
62#define PHYS_ADDR_MASK29		0x1fffffff
63#define PHYS_ADDR_MASK32		0xffffffff
64
65static inline unsigned long phys_addr_mask(void)
66{
67	/* Is the MMU in 29bit mode? */
68	if (__in_29bit_mode())
69		return PHYS_ADDR_MASK29;
70
71	return PHYS_ADDR_MASK32;
72}
73
74#define PTE_PHYS_MASK		(phys_addr_mask() & PAGE_MASK)
75#define PTE_FLAGS_MASK		(~(PTE_PHYS_MASK) << PAGE_SHIFT)
76
77#define VMALLOC_START	(P3SEG)
78#define VMALLOC_END	(FIXADDR_START-2*PAGE_SIZE)
79
80#include <asm/pgtable_32.h>
81
82/*
83 * SH-X and lower (legacy) SuperH parts (SH-3, SH-4, some SH-4A) can't do page
84 * protection for execute, and considers it the same as a read. Also, write
85 * permission implies read permission. This is the closest we can get..
86 *
87 * SH-X2 (SH7785) and later parts take this to the opposite end of the extreme,
88 * not only supporting separate execute, read, and write bits, but having
89 * completely separate permission bits for user and kernel space.
90 */
91	 /*xwr*/
92
93typedef pte_t *pte_addr_t;
94
95#define pte_pfn(x)		((unsigned long)(((x).pte_low >> PAGE_SHIFT)))
96
97struct vm_area_struct;
98struct mm_struct;
99
100extern void __update_cache(struct vm_area_struct *vma,
101			   unsigned long address, pte_t pte);
102extern void __update_tlb(struct vm_area_struct *vma,
103			 unsigned long address, pte_t pte);
104
105static inline void update_mmu_cache_range(struct vm_fault *vmf,
106		struct vm_area_struct *vma, unsigned long address,
107		pte_t *ptep, unsigned int nr)
108{
109	pte_t pte = *ptep;
110	__update_cache(vma, address, pte);
111	__update_tlb(vma, address, pte);
112}
113#define update_mmu_cache(vma, addr, ptep) \
114	update_mmu_cache_range(NULL, vma, addr, ptep, 1)
115
116extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
117extern void paging_init(void);
118extern void page_table_range_init(unsigned long start, unsigned long end,
119				  pgd_t *pgd);
120
121static inline bool __pte_access_permitted(pte_t pte, u64 prot)
122{
123	return (pte_val(pte) & (prot | _PAGE_SPECIAL)) == prot;
124}
125
126#ifdef CONFIG_X2TLB
127static inline bool pte_access_permitted(pte_t pte, bool write)
128{
129	u64 prot = _PAGE_PRESENT;
130
131	prot |= _PAGE_EXT(_PAGE_EXT_KERN_READ | _PAGE_EXT_USER_READ);
132	if (write)
133		prot |= _PAGE_EXT(_PAGE_EXT_KERN_WRITE | _PAGE_EXT_USER_WRITE);
134	return __pte_access_permitted(pte, prot);
135}
136#else
137static inline bool pte_access_permitted(pte_t pte, bool write)
138{
139	u64 prot = _PAGE_PRESENT | _PAGE_USER;
140
141	if (write)
142		prot |= _PAGE_RW;
143	return __pte_access_permitted(pte, prot);
144}
145#endif
146
147#define pte_access_permitted pte_access_permitted
148
149/* arch/sh/mm/mmap.c */
150#define HAVE_ARCH_UNMAPPED_AREA
151#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
152
153#endif /* __ASM_SH_PGTABLE_H */
154