summaryrefslogtreecommitdiffstats
path: root/arch/sh/mm/init.c
blob: f1a494283c4ee9341a35d92879f3f3ab24f44188 (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
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
/*
 * linux/arch/sh/mm/init.c
 *
 *  Copyright (C) 1999  Niibe Yutaka
 *  Copyright (C) 2002 - 2007  Paul Mundt
 *
 *  Based on linux/arch/i386/mm/init.c:
 *   Copyright (C) 1995  Linus Torvalds
 */
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/proc_fs.h>
#include <linux/pagemap.h>
#include <linux/percpu.h>
#include <linux/io.h>
#include <asm/mmu_context.h>
#include <asm/tlb.h>
#include <asm/cacheflush.h>
#include <asm/sections.h>
#include <asm/cache.h>

DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
pgd_t swapper_pg_dir[PTRS_PER_PGD];

#ifdef CONFIG_SUPERH32
/*
 * Handle trivial transitions between cached and uncached
 * segments, making use of the 1:1 mapping relationship in
 * 512MB lowmem.
 *
 * This is the offset of the uncached section from its cached alias.
 * Default value only valid in 29 bit mode, in 32bit mode will be
 * overridden in pmb_init.
 */
unsigned long cached_to_uncached = P2SEG - P1SEG;
#endif

#ifdef CONFIG_MMU
static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;

	pgd = pgd_offset_k(addr);
	if (pgd_none(*pgd)) {
		pgd_ERROR(*pgd);
		return;
	}

	pud = pud_alloc(NULL, pgd, addr);
	if (unlikely(!pud)) {
		pud_ERROR(*pud);
		return;
	}

	pmd = pmd_alloc(NULL, pud, addr);
	if (unlikely(!pmd)) {
		pmd_ERROR(*pmd);
		return;
	}

	pte = pte_offset_kernel(pmd, addr);
	if (!pte_none(*pte)) {
		pte_ERROR(*pte);
		return;
	}

	set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
	flush_tlb_one(get_asid(), addr);
}

/*
 * As a performance optimization, other platforms preserve the fixmap mapping
 * across a context switch, we don't presently do this, but this could be done
 * in a similar fashion as to the wired TLB interface that sh64 uses (by way
 * of the memory mapped UTLB configuration) -- this unfortunately forces us to
 * give up a TLB entry for each mapping we want to preserve. While this may be
 * viable for a small number of fixmaps, it's not particularly useful for
 * everything and needs to be carefully evaluated. (ie, we may want this for
 * the vsyscall page).
 *
 * XXX: Perhaps add a _PAGE_WIRED flag or something similar that we can pass
 * in at __set_fixmap() time to determine the appropriate behavior to follow.
 *
 *					 -- PFM.
 */
void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
{
	unsigned long address = __fix_to_virt(idx);

	if (idx >= __end_of_fixed_addresses) {
		BUG();
		return;
	}

	set_pte_phys(address, phys, prot);
}

void __init page_table_range_init(unsigned long start, unsigned long end,
					 pgd_t *pgd_base)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	int pgd_idx;
	unsigned long vaddr;

	vaddr = start & PMD_MASK;
	end = (end + PMD_SIZE - 1) & PMD_MASK;
	pgd_idx = pgd_index(vaddr);
	pgd = pgd_base + pgd_idx;

	for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd++, pgd_idx++) {
		BUG_ON(pgd_none(*pgd));
		pud = pud_offset(pgd, 0);
		BUG_ON(pud_none(*pud));
		pmd = pmd_offset(pud, 0);

		if (!pmd_present(*pmd)) {
			pte_t *pte_table;
			pte_table = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
			memset(pte_table, 0, PAGE_SIZE);
			pmd_populate_kernel(&init_mm, pmd, pte_table);
		}

		vaddr += PMD_SIZE;
	}
}
#endif	/* CONFIG_MMU */

/*
 * paging_init() sets up the page tables
 */
void __init paging_init(void)
{
	unsigned long max_zone_pfns[MAX_NR_ZONES];
	int nid;

	/* We don't need to map the kernel through the TLB, as
	 * it is permanatly mapped using P1. So clear the
	 * entire pgd. */
	memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));

	/* Set an initial value for the MMU.TTB so we don't have to
	 * check for a null value. */
	set_TTB(swapper_pg_dir);

	/* Populate the relevant portions of swapper_pg_dir so that
	 * we can use the fixmap entries without calling kmalloc.
	 * pte's will be filled in by __set_fixmap(). */
	page_table_range_init(FIXADDR_START, FIXADDR_TOP, swapper_pg_dir);

	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));

	for_each_online_node(nid) {
		pg_data_t *pgdat = NODE_DATA(nid);
		unsigned long low, start_pfn;

		start_pfn = pgdat->bdata->node_min_pfn;
		low = pgdat->bdata->node_low_pfn;

		if (max_zone_pfns[ZONE_NORMAL] < low)
			max_zone_pfns[ZONE_NORMAL] = low;

		printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
		       nid, start_pfn, low);
	}

	free_area_init_nodes(max_zone_pfns);

#ifdef CONFIG_SUPERH32
	/* Set up the uncached fixmap */
	set_fixmap_nocache(FIX_UNCACHED, __pa(&__uncached_start));
#endif
}

static struct kcore_list kcore_mem, kcore_vmalloc;
int after_bootmem = 0;

void __init mem_init(void)
{
	int codesize, datasize, initsize;
	int nid;

	num_physpages = 0;
	high_memory = NULL;

	for_each_online_node(nid) {
		pg_data_t *pgdat = NODE_DATA(nid);
		unsigned long node_pages = 0;
		void *node_high_memory;

		num_physpages += pgdat->node_present_pages;

		if (pgdat->node_spanned_pages)
			node_pages = free_all_bootmem_node(pgdat);

		totalram_pages += node_pages;

		node_high_memory = (void *)__va((pgdat->node_start_pfn +
						 pgdat->node_spanned_pages) <<
						 PAGE_SHIFT);
		if (node_high_memory > high_memory)
			high_memory = node_high_memory;
	}

	/* clear the zero-page */
	memset(empty_zero_page, 0, PAGE_SIZE);
	__flush_wback_region(empty_zero_page, PAGE_SIZE);

	after_bootmem = 1;

	codesize =  (unsigned long) &_etext - (unsigned long) &_text;
	datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;

	kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
	kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
		   VMALLOC_END - VMALLOC_START);

	printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
	       "%dk data, %dk init)\n",
		(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
		num_physpages << (PAGE_SHIFT-10),
		codesize >> 10,
		datasize >> 10,
		initsize >> 10);

	p3_cache_init();

	/* Initialize the vDSO */
	vsyscall_init();
}

void free_initmem(void)
{
	unsigned long addr;

	addr = (unsigned long)(&__init_begin);
	for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
		ClearPageReserved(virt_to_page(addr));
		init_page_count(virt_to_page(addr));
		free_page(addr);
		totalram_pages++;
	}
	printk("Freeing unused kernel memory: %ldk freed\n",
	       ((unsigned long)&__init_end -
	        (unsigned long)&__init_begin) >> 10);
}

#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
	unsigned long p;
	for (p = start; p < end; p += PAGE_SIZE) {
		ClearPageReserved(virt_to_page(p));
		init_page_count(virt_to_page(p));
		free_page(p);
		totalram_pages++;
	}
	printk("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
}
#endif

#ifdef CONFIG_MEMORY_HOTPLUG
int arch_add_memory(int nid, u64 start, u64 size)
{
	pg_data_t *pgdat;
	unsigned long start_pfn = start >> PAGE_SHIFT;
	unsigned long nr_pages = size >> PAGE_SHIFT;
	int ret;

	pgdat = NODE_DATA(nid);

	/* We only have ZONE_NORMAL, so this is easy.. */
	ret = __add_pages(pgdat->node_zones + ZONE_NORMAL, start_pfn, nr_pages);
	if (unlikely(ret))
		printk("%s: Failed, __add_pages() == %d\n", __func__, ret);

	return ret;
}
EXPORT_SYMBOL_GPL(arch_add_memory);

#ifdef CONFIG_NUMA
int memory_add_physaddr_to_nid(u64 addr)
{
	/* Node 0 for now.. */
	return 0;
}
EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
#endif

#ifdef CONFIG_MEMORY_HOTREMOVE
int remove_memory(u64 start, u64 size)
{
	unsigned long start_pfn = start >> PAGE_SHIFT;
	unsigned long end_pfn = start_pfn + (size >> PAGE_SHIFT);
	int ret;

	ret = offline_pages(start_pfn, end_pfn, 120 * HZ);
	if (unlikely(ret))
		printk("%s: Failed, offline_pages() == %d\n", __func__, ret);

	return ret;
}
EXPORT_SYMBOL_GPL(remove_memory);
#endif

#endif /* CONFIG_MEMORY_HOTPLUG */
OpenPOWER on IntegriCloud