summaryrefslogtreecommitdiff
path: root/arch/powerpc/include/asm/nohash/32/pgtable.h
blob: 0be464af4cb1ef2eab639b4ce62c346887f953f1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_POWERPC_NOHASH_32_PGTABLE_H
#define _ASM_POWERPC_NOHASH_32_PGTABLE_H

#include <asm-generic/pgtable-nopmd.h>

#ifndef __ASSEMBLY__
#include <linux/sched.h>
#include <linux/threads.h>
#include <asm/mmu.h>			/* For sub-arch specific PPC_PIN_SIZE */

#endif /* __ASSEMBLY__ */

#define PTE_INDEX_SIZE	PTE_SHIFT
#define PMD_INDEX_SIZE	0
#define PUD_INDEX_SIZE	0
#define PGD_INDEX_SIZE	(32 - PGDIR_SHIFT)

#define PMD_CACHE_INDEX	PMD_INDEX_SIZE
#define PUD_CACHE_INDEX	PUD_INDEX_SIZE

#ifndef __ASSEMBLY__
#define PTE_TABLE_SIZE	(sizeof(pte_t) << PTE_INDEX_SIZE)
#define PMD_TABLE_SIZE	0
#define PUD_TABLE_SIZE	0
#define PGD_TABLE_SIZE	(sizeof(pgd_t) << PGD_INDEX_SIZE)

#define PMD_MASKED_BITS (PTE_TABLE_SIZE - 1)
#endif	/* __ASSEMBLY__ */

#define PTRS_PER_PTE	(1 << PTE_INDEX_SIZE)
#define PTRS_PER_PGD	(1 << PGD_INDEX_SIZE)

/*
 * The normal case is that PTEs are 32-bits and we have a 1-page
 * 1024-entry pgdir pointing to 1-page 1024-entry PTE pages.  -- paulus
 *
 * For any >32-bit physical address platform, we can use the following
 * two level page table layout where the pgdir is 8KB and the MS 13 bits
 * are an index to the second level table.  The combined pgdir/pmd first
 * level has 2048 entries and the second level has 512 64-bit PTE entries.
 * -Matt
 */
/* PGDIR_SHIFT determines what a top-level page table entry can map */
#define PGDIR_SHIFT	(PAGE_SHIFT + PTE_INDEX_SIZE)
#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
#define PGDIR_MASK	(~(PGDIR_SIZE-1))

/* Bits to mask out from a PGD to get to the PUD page */
#define PGD_MASKED_BITS		0

#define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)

#define pgd_ERROR(e) \
	pr_err("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))

/*
 * This is the bottom of the PKMAP area with HIGHMEM or an arbitrary
 * value (for now) on others, from where we can start layout kernel
 * virtual space that goes below PKMAP and FIXMAP
 */

#define FIXADDR_SIZE	0
#ifdef CONFIG_KASAN
#include <asm/kasan.h>
#define FIXADDR_TOP	(KASAN_SHADOW_START - PAGE_SIZE)
#else
#define FIXADDR_TOP	((unsigned long)(-PAGE_SIZE))
#endif

/*
 * ioremap_bot starts at that address. Early ioremaps move down from there,
 * until mem_init() at which point this becomes the top of the vmalloc
 * and ioremap space
 */
#ifdef CONFIG_HIGHMEM
#define IOREMAP_TOP	PKMAP_BASE
#else
#define IOREMAP_TOP	FIXADDR_START
#endif

/* PPC32 shares vmalloc area with ioremap */
#define IOREMAP_START	VMALLOC_START
#define IOREMAP_END	VMALLOC_END

/*
 * Just any arbitrary offset to the start of the vmalloc VM area: the
 * current 16MB value just means that there will be a 64MB "hole" after the
 * physical memory until the kernel virtual memory starts.  That means that
 * any out-of-bounds memory accesses will hopefully be caught.
 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
 * area for the same reason. ;)
 *
 * We no longer map larger than phys RAM with the BATs so we don't have
 * to worry about the VMALLOC_OFFSET causing problems.  We do have to worry
 * about clashes between our early calls to ioremap() that start growing down
 * from IOREMAP_TOP being run into the VM area allocations (growing upwards
 * from VMALLOC_START).  For this reason we have ioremap_bot to check when
 * we actually run into our mappings setup in the early boot with the VM
 * system.  This really does become a problem for machines with good amounts
 * of RAM.  -- Cort
 */
#define VMALLOC_OFFSET (0x1000000) /* 16M */
#ifdef PPC_PIN_SIZE
#define VMALLOC_START (((ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
#else
#define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
#endif

#ifdef CONFIG_KASAN_VMALLOC
#define VMALLOC_END	ALIGN_DOWN(ioremap_bot, PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
#else
#define VMALLOC_END	ioremap_bot
#endif

/*
 * Bits in a linux-style PTE.  These match the bits in the
 * (hardware-defined) PowerPC PTE as closely as possible.
 */

#if defined(CONFIG_40x)
#include <asm/nohash/32/pte-40x.h>
#elif defined(CONFIG_44x)
#include <asm/nohash/32/pte-44x.h>
#elif defined(CONFIG_PPC_85xx) && defined(CONFIG_PTE_64BIT)
#include <asm/nohash/pte-e500.h>
#elif defined(CONFIG_PPC_85xx)
#include <asm/nohash/32/pte-85xx.h>
#elif defined(CONFIG_PPC_8xx)
#include <asm/nohash/32/pte-8xx.h>
#endif

/*
 * Location of the PFN in the PTE. Most 32-bit platforms use the same
 * as _PAGE_SHIFT here (ie, naturally aligned).
 * Platform who don't just pre-define the value so we don't override it here.
 */
#ifndef PTE_RPN_SHIFT
#define PTE_RPN_SHIFT	(PAGE_SHIFT)
#endif

/*
 * The mask covered by the RPN must be a ULL on 32-bit platforms with
 * 64-bit PTEs.
 */
#ifdef CONFIG_PTE_64BIT
#define PTE_RPN_MASK	(~((1ULL << PTE_RPN_SHIFT) - 1))
#define MAX_POSSIBLE_PHYSMEM_BITS 36
#else
#define PTE_RPN_MASK	(~((1UL << PTE_RPN_SHIFT) - 1))
#define MAX_POSSIBLE_PHYSMEM_BITS 32
#endif

#ifndef __ASSEMBLY__

#define pte_clear(mm, addr, ptep) \
	do { pte_update(mm, addr, ptep, ~0, 0, 0); } while (0)

#define pmd_none(pmd)		(!pmd_val(pmd))
#define	pmd_bad(pmd)		(pmd_val(pmd) & _PMD_BAD)
#define	pmd_present(pmd)	(pmd_val(pmd) & _PMD_PRESENT_MASK)
static inline void pmd_clear(pmd_t *pmdp)
{
	*pmdp = __pmd(0);
}

#ifndef __ptep_set_access_flags
static inline void __ptep_set_access_flags(struct vm_area_struct *vma,
					   pte_t *ptep, pte_t entry,
					   unsigned long address,
					   int psize)
{
	unsigned long set = pte_val(entry) &
			    (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
	int huge = psize > mmu_virtual_psize ? 1 : 0;

	pte_update(vma->vm_mm, address, ptep, 0, set, huge);

	flush_tlb_page(vma, address);
}
#endif

/*
 * Note that on Book E processors, the pmd contains the kernel virtual
 * (lowmem) address of the pte page.  The physical address is less useful
 * because everything runs with translation enabled (even the TLB miss
 * handler).  On everything else the pmd contains the physical address
 * of the pte page.  -- paulus
 */
#ifndef CONFIG_BOOKE
#define pmd_pfn(pmd)		(pmd_val(pmd) >> PAGE_SHIFT)
#else
#define pmd_page_vaddr(pmd)	\
	((const void *)(pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1)))
#define pmd_pfn(pmd)		(__pa(pmd_val(pmd)) >> PAGE_SHIFT)
#endif

#define pmd_page(pmd)		pfn_to_page(pmd_pfn(pmd))

/*
 * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
 * are !pte_none() && !pte_present().
 *
 * Format of swap PTEs (32bit PTEs):
 *
 *                         1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
 *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *   <------------------ offset -------------------> < type -> E 0 0
 *
 * E is the exclusive marker that is not stored in swap entries.
 *
 * For 64bit PTEs, the offset is extended by 32bit.
 */
#define __swp_type(entry)		((entry).val & 0x1f)
#define __swp_offset(entry)		((entry).val >> 5)
#define __swp_entry(type, offset)	((swp_entry_t) { ((type) & 0x1f) | ((offset) << 5) })
#define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) >> 3 })
#define __swp_entry_to_pte(x)		((pte_t) { (x).val << 3 })

/* We borrow LSB 2 to store the exclusive marker in swap PTEs. */
#define _PAGE_SWP_EXCLUSIVE	0x000004

#endif /* !__ASSEMBLY__ */

#endif /* __ASM_POWERPC_NOHASH_32_PGTABLE_H */