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
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* This file contains the routines for initializing the MMU
* on the 8xx series of chips.
* -- christophe
*
* Derived from arch/powerpc/mm/40x_mmu.c:
*/
#include <linux/memblock.h>
#include <linux/hugetlb.h>
#include <mm/mmu_decl.h>
#define IMMR_SIZE (FIX_IMMR_SIZE << PAGE_SHIFT)
static unsigned long block_mapped_ram;
/*
* Return PA for this VA if it is in an area mapped with LTLBs or fixmap.
* Otherwise, returns 0
*/
phys_addr_t v_block_mapped(unsigned long va)
{
unsigned long p = PHYS_IMMR_BASE;
if (va >= VIRT_IMMR_BASE && va < VIRT_IMMR_BASE + IMMR_SIZE)
return p + va - VIRT_IMMR_BASE;
if (va >= PAGE_OFFSET && va < PAGE_OFFSET + block_mapped_ram)
return __pa(va);
return 0;
}
/*
* Return VA for a given PA mapped with LTLBs or fixmap
* Return 0 if not mapped
*/
unsigned long p_block_mapped(phys_addr_t pa)
{
unsigned long p = PHYS_IMMR_BASE;
if (pa >= p && pa < p + IMMR_SIZE)
return VIRT_IMMR_BASE + pa - p;
if (pa < block_mapped_ram)
return (unsigned long)__va(pa);
return 0;
}
static pte_t __init *early_hugepd_alloc_kernel(hugepd_t *pmdp, unsigned long va)
{
if (hpd_val(*pmdp) == 0) {
pte_t *ptep = memblock_alloc(sizeof(pte_basic_t), SZ_4K);
if (!ptep)
return NULL;
hugepd_populate_kernel((hugepd_t *)pmdp, ptep, PAGE_SHIFT_8M);
hugepd_populate_kernel((hugepd_t *)pmdp + 1, ptep, PAGE_SHIFT_8M);
}
return hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT);
}
static int __ref __early_map_kernel_hugepage(unsigned long va, phys_addr_t pa,
pgprot_t prot, int psize, bool new)
{
pmd_t *pmdp = pmd_off_k(va);
pte_t *ptep;
if (WARN_ON(psize != MMU_PAGE_512K && psize != MMU_PAGE_8M))
return -EINVAL;
if (new) {
if (WARN_ON(slab_is_available()))
return -EINVAL;
if (psize == MMU_PAGE_512K)
ptep = early_pte_alloc_kernel(pmdp, va);
else
ptep = early_hugepd_alloc_kernel((hugepd_t *)pmdp, va);
} else {
if (psize == MMU_PAGE_512K)
ptep = pte_offset_kernel(pmdp, va);
else
ptep = hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT);
}
if (WARN_ON(!ptep))
return -ENOMEM;
/* The PTE should never be already present */
if (new && WARN_ON(pte_present(*ptep) && pgprot_val(prot)))
return -EINVAL;
set_huge_pte_at(&init_mm, va, ptep, pte_mkhuge(pfn_pte(pa >> PAGE_SHIFT, prot)));
return 0;
}
/*
* MMU_init_hw does the chip-specific initialization of the MMU hardware.
*/
void __init MMU_init_hw(void)
{
}
static bool immr_is_mapped __initdata;
void __init mmu_mapin_immr(void)
{
if (immr_is_mapped)
return;
immr_is_mapped = true;
__early_map_kernel_hugepage(VIRT_IMMR_BASE, PHYS_IMMR_BASE,
PAGE_KERNEL_NCG, MMU_PAGE_512K, true);
}
static void mmu_mapin_ram_chunk(unsigned long offset, unsigned long top,
pgprot_t prot, bool new)
{
unsigned long v = PAGE_OFFSET + offset;
unsigned long p = offset;
WARN_ON(!IS_ALIGNED(offset, SZ_512K) || !IS_ALIGNED(top, SZ_512K));
for (; p < ALIGN(p, SZ_8M) && p < top; p += SZ_512K, v += SZ_512K)
__early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new);
for (; p < ALIGN_DOWN(top, SZ_8M) && p < top; p += SZ_8M, v += SZ_8M)
__early_map_kernel_hugepage(v, p, prot, MMU_PAGE_8M, new);
for (; p < ALIGN_DOWN(top, SZ_512K) && p < top; p += SZ_512K, v += SZ_512K)
__early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new);
if (!new)
flush_tlb_kernel_range(PAGE_OFFSET + v, PAGE_OFFSET + top);
}
unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top)
{
unsigned long etext8 = ALIGN(__pa(_etext), SZ_8M);
unsigned long sinittext = __pa(_sinittext);
bool strict_boundary = strict_kernel_rwx_enabled() || debug_pagealloc_enabled_or_kfence();
unsigned long boundary = strict_boundary ? sinittext : etext8;
unsigned long einittext8 = ALIGN(__pa(_einittext), SZ_8M);
WARN_ON(top < einittext8);
mmu_mapin_immr();
mmu_mapin_ram_chunk(0, boundary, PAGE_KERNEL_TEXT, true);
if (debug_pagealloc_enabled_or_kfence()) {
top = boundary;
} else {
mmu_mapin_ram_chunk(boundary, einittext8, PAGE_KERNEL_TEXT, true);
mmu_mapin_ram_chunk(einittext8, top, PAGE_KERNEL, true);
}
if (top > SZ_32M)
memblock_set_current_limit(top);
block_mapped_ram = top;
return top;
}
void mmu_mark_initmem_nx(void)
{
unsigned long etext8 = ALIGN(__pa(_etext), SZ_8M);
unsigned long sinittext = __pa(_sinittext);
unsigned long boundary = strict_kernel_rwx_enabled() ? sinittext : etext8;
unsigned long einittext8 = ALIGN(__pa(_einittext), SZ_8M);
if (!debug_pagealloc_enabled_or_kfence())
mmu_mapin_ram_chunk(boundary, einittext8, PAGE_KERNEL, false);
mmu_pin_tlb(block_mapped_ram, false);
}
#ifdef CONFIG_STRICT_KERNEL_RWX
void mmu_mark_rodata_ro(void)
{
unsigned long sinittext = __pa(_sinittext);
mmu_mapin_ram_chunk(0, sinittext, PAGE_KERNEL_ROX, false);
if (IS_ENABLED(CONFIG_PIN_TLB_DATA))
mmu_pin_tlb(block_mapped_ram, true);
}
#endif
void __init setup_initial_memory_limit(phys_addr_t first_memblock_base,
phys_addr_t first_memblock_size)
{
/* We don't currently support the first MEMBLOCK not mapping 0
* physical on those processors
*/
BUG_ON(first_memblock_base != 0);
/* 8xx can only access 32MB at the moment */
memblock_set_current_limit(min_t(u64, first_memblock_size, SZ_32M));
}
int pud_clear_huge(pud_t *pud)
{
return 0;
}
int pmd_clear_huge(pmd_t *pmd)
{
return 0;
}
|
