summaryrefslogtreecommitdiffstats
path: root/arch/csky/mm/init.c
blob: 7742f1441a67d326d64867fc7c7ef14cd52ac293 (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
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.

#include <linux/bug.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/pagemap.h>
#include <linux/ptrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/memblock.h>
#include <linux/swap.h>
#include <linux/proc_fs.h>
#include <linux/pfn.h>
#include <linux/initrd.h>

#include <asm/setup.h>
#include <asm/cachectl.h>
#include <asm/dma.h>
#include <asm/pgalloc.h>
#include <asm/mmu_context.h>
#include <asm/sections.h>
#include <asm/tlb.h>
#include <asm/cacheflush.h>

pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;
pte_t kernel_pte_tables[(PTRS_PER_PGD - USER_PTRS_PER_PGD)*PTRS_PER_PTE] __page_aligned_bss;

EXPORT_SYMBOL(invalid_pte_table);
unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
						__page_aligned_bss;
EXPORT_SYMBOL(empty_zero_page);

#ifdef CONFIG_BLK_DEV_INITRD
static void __init setup_initrd(void)
{
	unsigned long size;

	if (initrd_start >= initrd_end) {
		pr_err("initrd not found or empty");
		goto disable;
	}

	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
		pr_err("initrd extends beyond end of memory");
		goto disable;
	}

	size = initrd_end - initrd_start;

	if (memblock_is_region_reserved(__pa(initrd_start), size)) {
		pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use memory region",
		       __pa(initrd_start), size);
		goto disable;
	}

	memblock_reserve(__pa(initrd_start), size);

	pr_info("Initial ramdisk at: 0x%p (%lu bytes)\n",
		(void *)(initrd_start), size);

	initrd_below_start_ok = 1;

	return;

disable:
	initrd_start = initrd_end = 0;

	pr_err(" - disabling initrd\n");
}
#endif

void __init mem_init(void)
{
#ifdef CONFIG_HIGHMEM
	unsigned long tmp;

	max_mapnr = highend_pfn;
#else
	max_mapnr = max_low_pfn;
#endif
	high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);

#ifdef CONFIG_BLK_DEV_INITRD
	setup_initrd();
#endif

	memblock_free_all();

#ifdef CONFIG_HIGHMEM
	for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
		struct page *page = pfn_to_page(tmp);

		/* FIXME not sure about */
		if (!memblock_is_reserved(tmp << PAGE_SHIFT))
			free_highmem_page(page);
	}
#endif
	mem_init_print_info(NULL);
}

extern char __init_begin[], __init_end[];

void free_initmem(void)
{
	unsigned long addr;

	addr = (unsigned long) &__init_begin;

	while (addr < (unsigned long) &__init_end) {
		ClearPageReserved(virt_to_page(addr));
		init_page_count(virt_to_page(addr));
		free_page(addr);
		totalram_pages_inc();
		addr += PAGE_SIZE;
	}

	pr_info("Freeing unused kernel memory: %dk freed\n",
	((unsigned int)&__init_end - (unsigned int)&__init_begin) >> 10);
}

void pgd_init(unsigned long *p)
{
	int i;

	for (i = 0; i < PTRS_PER_PGD; i++)
		p[i] = __pa(invalid_pte_table);

	flush_tlb_all();
	local_icache_inv_all(NULL);
}

void __init mmu_init(unsigned long min_pfn, unsigned long max_pfn)
{
	int i;

	for (i = 0; i < USER_PTRS_PER_PGD; i++)
		swapper_pg_dir[i].pgd = __pa(invalid_pte_table);

	for (i = USER_PTRS_PER_PGD; i < PTRS_PER_PGD; i++)
		swapper_pg_dir[i].pgd =
			__pa(kernel_pte_tables + (PTRS_PER_PTE * (i - USER_PTRS_PER_PGD)));

	for (i = min_pfn; i < max_pfn; i++)
		set_pte(&kernel_pte_tables[i - PFN_DOWN(va_pa_offset)], pfn_pte(i, PAGE_KERNEL));

	flush_tlb_all();
	local_icache_inv_all(NULL);

	/* Setup page mask to 4k */
	write_mmu_pagemask(0);

	setup_pgd(swapper_pg_dir);
}

void __init fixrange_init(unsigned long start, unsigned long end,
			pgd_t *pgd_base)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;
	int i, j, k;
	unsigned long vaddr;

	vaddr = start;
	i = pgd_index(vaddr);
	j = pud_index(vaddr);
	k = pmd_index(vaddr);
	pgd = pgd_base + i;

	for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
		pud = (pud_t *)pgd;
		for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
			pmd = (pmd_t *)pud;
			for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
				if (pmd_none(*pmd)) {
					pte = (pte_t *) memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
					if (!pte)
						panic("%s: Failed to allocate %lu bytes align=%lx\n",
						      __func__, PAGE_SIZE,
						      PAGE_SIZE);

					set_pmd(pmd, __pmd(__pa(pte)));
					BUG_ON(pte != pte_offset_kernel(pmd, 0));
				}
				vaddr += PMD_SIZE;
			}
			k = 0;
		}
		j = 0;
	}
}

void __init fixaddr_init(void)
{
	unsigned long vaddr;

	vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
	fixrange_init(vaddr, vaddr + PMD_SIZE, swapper_pg_dir);
}