1/*
2 * arch/xtensa/mm/init.c
3 *
4 * Derived from MIPS, PPC.
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License.  See the file "COPYING" in the main directory of this archive
8 * for more details.
9 *
10 * Copyright (C) 2001 - 2005 Tensilica Inc.
11 *
12 * Chris Zankel	<chris@zankel.net>
13 * Joe Taylor	<joe@tensilica.com, joetylr@yahoo.com>
14 * Marc Gauthier
15 * Kevin Chea
16 */
17
18#include <linux/kernel.h>
19#include <linux/errno.h>
20#include <linux/bootmem.h>
21#include <linux/gfp.h>
22#include <linux/swap.h>
23#include <linux/mman.h>
24#include <linux/nodemask.h>
25#include <linux/mm.h>
26
27#include <asm/bootparam.h>
28#include <asm/page.h>
29
30/* References to section boundaries */
31
32extern char _ftext, _etext, _fdata, _edata, _rodata_end;
33extern char __init_begin, __init_end;
34
35/*
36 * mem_reserve(start, end, must_exist)
37 *
38 * Reserve some memory from the memory pool.
39 *
40 * Parameters:
41 *  start	Start of region,
42 *  end		End of region,
43 *  must_exist	Must exist in memory pool.
44 *
45 * Returns:
46 *  0 (memory area couldn't be mapped)
47 * -1 (success)
48 */
49
50int __init mem_reserve(unsigned long start, unsigned long end, int must_exist)
51{
52	int i;
53
54	if (start == end)
55		return 0;
56
57	start = start & PAGE_MASK;
58	end = PAGE_ALIGN(end);
59
60	for (i = 0; i < sysmem.nr_banks; i++)
61		if (start < sysmem.bank[i].end
62		    && end >= sysmem.bank[i].start)
63			break;
64
65	if (i == sysmem.nr_banks) {
66		if (must_exist)
67			printk (KERN_WARNING "mem_reserve: [0x%0lx, 0x%0lx) "
68				"not in any region!\n", start, end);
69		return 0;
70	}
71
72	if (start > sysmem.bank[i].start) {
73		if (end < sysmem.bank[i].end) {
74			/* split entry */
75			if (sysmem.nr_banks >= SYSMEM_BANKS_MAX)
76				panic("meminfo overflow\n");
77			sysmem.bank[sysmem.nr_banks].start = end;
78			sysmem.bank[sysmem.nr_banks].end = sysmem.bank[i].end;
79			sysmem.nr_banks++;
80		}
81		sysmem.bank[i].end = start;
82	} else {
83		if (end < sysmem.bank[i].end)
84			sysmem.bank[i].start = end;
85		else {
86			/* remove entry */
87			sysmem.nr_banks--;
88			sysmem.bank[i].start = sysmem.bank[sysmem.nr_banks].start;
89			sysmem.bank[i].end   = sysmem.bank[sysmem.nr_banks].end;
90		}
91	}
92	return -1;
93}
94
95
96/*
97 * Initialize the bootmem system and give it all the memory we have available.
98 */
99
100void __init bootmem_init(void)
101{
102	unsigned long pfn;
103	unsigned long bootmap_start, bootmap_size;
104	int i;
105
106	max_low_pfn = max_pfn = 0;
107	min_low_pfn = ~0;
108
109	for (i=0; i < sysmem.nr_banks; i++) {
110		pfn = PAGE_ALIGN(sysmem.bank[i].start) >> PAGE_SHIFT;
111		if (pfn < min_low_pfn)
112			min_low_pfn = pfn;
113		pfn = PAGE_ALIGN(sysmem.bank[i].end - 1) >> PAGE_SHIFT;
114		if (pfn > max_pfn)
115			max_pfn = pfn;
116	}
117
118	if (min_low_pfn > max_pfn)
119		panic("No memory found!\n");
120
121	max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ?
122		max_pfn : MAX_MEM_PFN >> PAGE_SHIFT;
123
124	/* Find an area to use for the bootmem bitmap. */
125
126	bootmap_size = bootmem_bootmap_pages(max_low_pfn - min_low_pfn);
127	bootmap_size <<= PAGE_SHIFT;
128	bootmap_start = ~0;
129
130	for (i=0; i<sysmem.nr_banks; i++)
131		if (sysmem.bank[i].end - sysmem.bank[i].start >= bootmap_size) {
132			bootmap_start = sysmem.bank[i].start;
133			break;
134		}
135
136	if (bootmap_start == ~0UL)
137		panic("Cannot find %ld bytes for bootmap\n", bootmap_size);
138
139	/* Reserve the bootmem bitmap area */
140
141	mem_reserve(bootmap_start, bootmap_start + bootmap_size, 1);
142	bootmap_size = init_bootmem_node(NODE_DATA(0),
143					 bootmap_start >> PAGE_SHIFT,
144					 min_low_pfn,
145					 max_low_pfn);
146
147	/* Add all remaining memory pieces into the bootmem map */
148
149	for (i=0; i<sysmem.nr_banks; i++)
150		free_bootmem(sysmem.bank[i].start,
151			     sysmem.bank[i].end - sysmem.bank[i].start);
152
153}
154
155
156void __init zones_init(void)
157{
158	unsigned long zones_size[MAX_NR_ZONES];
159	int i;
160
161	/* All pages are DMA-able, so we put them all in the DMA zone. */
162
163	zones_size[ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET;
164	for (i = 1; i < MAX_NR_ZONES; i++)
165		zones_size[i] = 0;
166
167#ifdef CONFIG_HIGHMEM
168	zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;
169#endif
170
171	free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL);
172}
173
174/*
175 * Initialize memory pages.
176 */
177
178void __init mem_init(void)
179{
180	unsigned long codesize, reservedpages, datasize, initsize;
181	unsigned long highmemsize, tmp, ram;
182
183	max_mapnr = num_physpages = max_low_pfn - ARCH_PFN_OFFSET;
184	high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
185	highmemsize = 0;
186
187#ifdef CONFIG_HIGHMEM
188#error HIGHGMEM not implemented in init.c
189#endif
190
191	totalram_pages += free_all_bootmem();
192
193	reservedpages = ram = 0;
194	for (tmp = 0; tmp < max_mapnr; tmp++) {
195		ram++;
196		if (PageReserved(mem_map+tmp))
197			reservedpages++;
198	}
199
200	codesize =  (unsigned long) &_etext - (unsigned long) &_ftext;
201	datasize =  (unsigned long) &_edata - (unsigned long) &_fdata;
202	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
203
204	printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, "
205	       "%ldk data, %ldk init %ldk highmem)\n",
206	       nr_free_pages() << (PAGE_SHIFT-10),
207	       ram << (PAGE_SHIFT-10),
208	       codesize >> 10,
209	       reservedpages << (PAGE_SHIFT-10),
210	       datasize >> 10,
211	       initsize >> 10,
212	       highmemsize >> 10);
213}
214
215void
216free_reserved_mem(void *start, void *end)
217{
218	for (; start < end; start += PAGE_SIZE) {
219		ClearPageReserved(virt_to_page(start));
220		init_page_count(virt_to_page(start));
221		free_page((unsigned long)start);
222		totalram_pages++;
223	}
224}
225
226#ifdef CONFIG_BLK_DEV_INITRD
227extern int initrd_is_mapped;
228
229void free_initrd_mem(unsigned long start, unsigned long end)
230{
231	if (initrd_is_mapped) {
232		free_reserved_mem((void*)start, (void*)end);
233		printk ("Freeing initrd memory: %ldk freed\n",(end-start)>>10);
234	}
235}
236#endif
237
238void free_initmem(void)
239{
240	free_reserved_mem(&__init_begin, &__init_end);
241	printk("Freeing unused kernel memory: %dk freed\n",
242	       (&__init_end - &__init_begin) >> 10);
243}
244