xref: /openbmc/linux/arch/microblaze/mm/init.c (revision b627b4ed)
1 /*
2  * Copyright (C) 2007-2008 Michal Simek <monstr@monstr.eu>
3  * Copyright (C) 2006 Atmark Techno, Inc.
4  *
5  * This file is subject to the terms and conditions of the GNU General Public
6  * License. See the file "COPYING" in the main directory of this archive
7  * for more details.
8  */
9 
10 #include <linux/bootmem.h>
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/lmb.h>
14 #include <linux/mm.h> /* mem_init */
15 #include <linux/initrd.h>
16 #include <linux/pagemap.h>
17 #include <linux/pfn.h>
18 #include <linux/swap.h>
19 
20 #include <asm/page.h>
21 #include <asm/mmu_context.h>
22 #include <asm/pgalloc.h>
23 #include <asm/sections.h>
24 #include <asm/tlb.h>
25 
26 unsigned int __page_offset;
27 /* EXPORT_SYMBOL(__page_offset); */
28 
29 char *klimit = _end;
30 
31 /*
32  * Initialize the bootmem system and give it all the memory we
33  * have available.
34  */
35 unsigned int memory_start;
36 unsigned int memory_end; /* due to mm/nommu.c */
37 unsigned int memory_size;
38 
39 /*
40  * paging_init() sets up the page tables - in fact we've already done this.
41  */
42 static void __init paging_init(void)
43 {
44 	int i;
45 	unsigned long zones_size[MAX_NR_ZONES];
46 
47 	/*
48 	 * old: we can DMA to/from any address.put all page into ZONE_DMA
49 	 * We use only ZONE_NORMAL
50 	 */
51 	zones_size[ZONE_NORMAL] = max_mapnr;
52 
53 	/* every other zones are empty */
54 	for (i = 1; i < MAX_NR_ZONES; i++)
55 		zones_size[i] = 0;
56 
57 	free_area_init(zones_size);
58 }
59 
60 void __init setup_memory(void)
61 {
62 	int i;
63 	unsigned long map_size;
64 	u32 kernel_align_start, kernel_align_size;
65 
66 	/* Find main memory where is the kernel */
67 	for (i = 0; i < lmb.memory.cnt; i++) {
68 		memory_start = (u32) lmb.memory.region[i].base;
69 		memory_end = (u32) lmb.memory.region[i].base
70 				+ (u32) lmb.memory.region[i].size;
71 		if ((memory_start <= (u32)_text) &&
72 					((u32)_text <= memory_end)) {
73 			memory_size = memory_end - memory_start;
74 			PAGE_OFFSET = memory_start;
75 			printk(KERN_INFO "%s: Main mem: 0x%x-0x%x, "
76 				"size 0x%08x\n", __func__, memory_start,
77 						memory_end, memory_size);
78 			break;
79 		}
80 	}
81 
82 	if (!memory_start || !memory_end) {
83 		panic("%s: Missing memory setting 0x%08x-0x%08x\n",
84 			__func__, memory_start, memory_end);
85 	}
86 
87 	/* reservation of region where is the kernel */
88 	kernel_align_start = PAGE_DOWN((u32)_text);
89 	/* ALIGN can be remove because _end in vmlinux.lds.S is align */
90 	kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
91 	lmb_reserve(kernel_align_start, kernel_align_size);
92 	printk(KERN_INFO "%s: kernel addr=0x%08x-0x%08x size=0x%08x\n",
93 		__func__, kernel_align_start, kernel_align_start
94 			+ kernel_align_size, kernel_align_size);
95 
96 	/*
97 	 * Kernel:
98 	 * start: base phys address of kernel - page align
99 	 * end: base phys address of kernel - page align
100 	 *
101 	 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
102 	 * max_low_pfn
103 	 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
104 	 * num_physpages - number of all pages
105 	 */
106 
107 	/* memory start is from the kernel end (aligned) to higher addr */
108 	min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
109 	/* RAM is assumed contiguous */
110 	num_physpages = max_mapnr = memory_size >> PAGE_SHIFT;
111 	max_pfn = max_low_pfn = memory_end >> PAGE_SHIFT;
112 
113 	printk(KERN_INFO "%s: max_mapnr: %#lx\n", __func__, max_mapnr);
114 	printk(KERN_INFO "%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
115 	printk(KERN_INFO "%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
116 
117 	/*
118 	 * Find an area to use for the bootmem bitmap.
119 	 * We look for the first area which is at least
120 	 * 128kB in length (128kB is enough for a bitmap
121 	 * for 4GB of memory, using 4kB pages), plus 1 page
122 	 * (in case the address isn't page-aligned).
123 	 */
124 	map_size = init_bootmem_node(NODE_DATA(0), PFN_UP(TOPHYS((u32)_end)),
125 					min_low_pfn, max_low_pfn);
126 
127 	lmb_reserve(PFN_UP(TOPHYS((u32)_end)) << PAGE_SHIFT, map_size);
128 
129 	/* free bootmem is whole main memory */
130 	free_bootmem(memory_start, memory_size);
131 
132 	/* reserve allocate blocks */
133 	for (i = 0; i < lmb.reserved.cnt; i++) {
134 		pr_debug("reserved %d - 0x%08x-0x%08x\n", i,
135 			(u32) lmb.reserved.region[i].base,
136 			(u32) lmb_size_bytes(&lmb.reserved, i));
137 		reserve_bootmem(lmb.reserved.region[i].base,
138 			lmb_size_bytes(&lmb.reserved, i) - 1, BOOTMEM_DEFAULT);
139 	}
140 	paging_init();
141 }
142 
143 void free_init_pages(char *what, unsigned long begin, unsigned long end)
144 {
145 	unsigned long addr;
146 
147 	for (addr = begin; addr < end; addr += PAGE_SIZE) {
148 		ClearPageReserved(virt_to_page(addr));
149 		init_page_count(virt_to_page(addr));
150 		memset((void *)addr, 0xcc, PAGE_SIZE);
151 		free_page(addr);
152 		totalram_pages++;
153 	}
154 	printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
155 }
156 
157 #ifdef CONFIG_BLK_DEV_INITRD
158 void free_initrd_mem(unsigned long start, unsigned long end)
159 {
160 	int pages = 0;
161 	for (; start < end; start += PAGE_SIZE) {
162 		ClearPageReserved(virt_to_page(start));
163 		init_page_count(virt_to_page(start));
164 		free_page(start);
165 		totalram_pages++;
166 		pages++;
167 	}
168 	printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n", pages);
169 }
170 #endif
171 
172 void free_initmem(void)
173 {
174 	free_init_pages("unused kernel memory",
175 			(unsigned long)(&__init_begin),
176 			(unsigned long)(&__init_end));
177 }
178 
179 /* FIXME from arch/powerpc/mm/mem.c*/
180 void show_mem(void)
181 {
182 	printk(KERN_NOTICE "%s\n", __func__);
183 }
184 
185 void __init mem_init(void)
186 {
187 	high_memory = (void *)__va(memory_end);
188 	/* this will put all memory onto the freelists */
189 	totalram_pages += free_all_bootmem();
190 
191 	printk(KERN_INFO "Memory: %luk/%luk available\n",
192 	       (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
193 	       num_physpages << (PAGE_SHIFT-10));
194 }
195 
196 /* Check against bounds of physical memory */
197 int ___range_ok(unsigned long addr, unsigned long size)
198 {
199 	return ((addr < memory_start) ||
200 		((addr + size) > memory_end));
201 }
202