xref: /linux/arch/powerpc/mm/init_64.c (revision 27258e448eb301cf89e351df87aa8cb916653bf2)
1 /*
2  *  PowerPC version
3  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
4  *
5  *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
6  *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
7  *    Copyright (C) 1996 Paul Mackerras
8  *
9  *  Derived from "arch/i386/mm/init.c"
10  *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
11  *
12  *  Dave Engebretsen <engebret@us.ibm.com>
13  *      Rework for PPC64 port.
14  *
15  *  This program is free software; you can redistribute it and/or
16  *  modify it under the terms of the GNU General Public License
17  *  as published by the Free Software Foundation; either version
18  *  2 of the License, or (at your option) any later version.
19  *
20  */
21 
22 #undef DEBUG
23 
24 #include <linux/signal.h>
25 #include <linux/sched.h>
26 #include <linux/kernel.h>
27 #include <linux/errno.h>
28 #include <linux/string.h>
29 #include <linux/types.h>
30 #include <linux/mman.h>
31 #include <linux/mm.h>
32 #include <linux/swap.h>
33 #include <linux/stddef.h>
34 #include <linux/vmalloc.h>
35 #include <linux/init.h>
36 #include <linux/delay.h>
37 #include <linux/bootmem.h>
38 #include <linux/highmem.h>
39 #include <linux/idr.h>
40 #include <linux/nodemask.h>
41 #include <linux/module.h>
42 #include <linux/poison.h>
43 #include <linux/lmb.h>
44 
45 #include <asm/pgalloc.h>
46 #include <asm/page.h>
47 #include <asm/prom.h>
48 #include <asm/rtas.h>
49 #include <asm/io.h>
50 #include <asm/mmu_context.h>
51 #include <asm/pgtable.h>
52 #include <asm/mmu.h>
53 #include <asm/uaccess.h>
54 #include <asm/smp.h>
55 #include <asm/machdep.h>
56 #include <asm/tlb.h>
57 #include <asm/eeh.h>
58 #include <asm/processor.h>
59 #include <asm/mmzone.h>
60 #include <asm/cputable.h>
61 #include <asm/sections.h>
62 #include <asm/system.h>
63 #include <asm/iommu.h>
64 #include <asm/abs_addr.h>
65 #include <asm/vdso.h>
66 
67 #include "mmu_decl.h"
68 
69 #ifdef CONFIG_PPC_STD_MMU_64
70 #if PGTABLE_RANGE > USER_VSID_RANGE
71 #warning Limited user VSID range means pagetable space is wasted
72 #endif
73 
74 #if (TASK_SIZE_USER64 < PGTABLE_RANGE) && (TASK_SIZE_USER64 < USER_VSID_RANGE)
75 #warning TASK_SIZE is smaller than it needs to be.
76 #endif
77 #endif /* CONFIG_PPC_STD_MMU_64 */
78 
79 phys_addr_t memstart_addr = ~0;
80 phys_addr_t kernstart_addr;
81 
82 void free_initmem(void)
83 {
84 	unsigned long addr;
85 
86 	addr = (unsigned long)__init_begin;
87 	for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) {
88 		memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
89 		ClearPageReserved(virt_to_page(addr));
90 		init_page_count(virt_to_page(addr));
91 		free_page(addr);
92 		totalram_pages++;
93 	}
94 	printk ("Freeing unused kernel memory: %luk freed\n",
95 		((unsigned long)__init_end - (unsigned long)__init_begin) >> 10);
96 }
97 
98 #ifdef CONFIG_BLK_DEV_INITRD
99 void free_initrd_mem(unsigned long start, unsigned long end)
100 {
101 	if (start < end)
102 		printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
103 	for (; start < end; start += PAGE_SIZE) {
104 		ClearPageReserved(virt_to_page(start));
105 		init_page_count(virt_to_page(start));
106 		free_page(start);
107 		totalram_pages++;
108 	}
109 }
110 #endif
111 
112 #ifdef CONFIG_PROC_KCORE
113 static struct kcore_list kcore_vmem;
114 
115 static int __init setup_kcore(void)
116 {
117 	int i;
118 
119 	for (i=0; i < lmb.memory.cnt; i++) {
120 		unsigned long base, size;
121 		struct kcore_list *kcore_mem;
122 
123 		base = lmb.memory.region[i].base;
124 		size = lmb.memory.region[i].size;
125 
126 		/* GFP_ATOMIC to avoid might_sleep warnings during boot */
127 		kcore_mem = kmalloc(sizeof(struct kcore_list), GFP_ATOMIC);
128 		if (!kcore_mem)
129 			panic("%s: kmalloc failed\n", __func__);
130 
131 		kclist_add(kcore_mem, __va(base), size);
132 	}
133 
134 	kclist_add(&kcore_vmem, (void *)VMALLOC_START, VMALLOC_END-VMALLOC_START);
135 
136 	return 0;
137 }
138 module_init(setup_kcore);
139 #endif
140 
141 static void pgd_ctor(void *addr)
142 {
143 	memset(addr, 0, PGD_TABLE_SIZE);
144 }
145 
146 static void pmd_ctor(void *addr)
147 {
148 	memset(addr, 0, PMD_TABLE_SIZE);
149 }
150 
151 static const unsigned int pgtable_cache_size[2] = {
152 	PGD_TABLE_SIZE, PMD_TABLE_SIZE
153 };
154 static const char *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
155 #ifdef CONFIG_PPC_64K_PAGES
156 	"pgd_cache", "pmd_cache",
157 #else
158 	"pgd_cache", "pud_pmd_cache",
159 #endif /* CONFIG_PPC_64K_PAGES */
160 };
161 
162 #ifdef CONFIG_HUGETLB_PAGE
163 /* Hugepages need an extra cache per hugepagesize, initialized in
164  * hugetlbpage.c.  We can't put into the tables above, because HPAGE_SHIFT
165  * is not compile time constant. */
166 struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+MMU_PAGE_COUNT];
167 #else
168 struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
169 #endif
170 
171 void pgtable_cache_init(void)
172 {
173 	pgtable_cache[0] = kmem_cache_create(pgtable_cache_name[0], PGD_TABLE_SIZE, PGD_TABLE_SIZE, SLAB_PANIC, pgd_ctor);
174 	pgtable_cache[1] = kmem_cache_create(pgtable_cache_name[1], PMD_TABLE_SIZE, PMD_TABLE_SIZE, SLAB_PANIC, pmd_ctor);
175 }
176 
177 #ifdef CONFIG_SPARSEMEM_VMEMMAP
178 /*
179  * Given an address within the vmemmap, determine the pfn of the page that
180  * represents the start of the section it is within.  Note that we have to
181  * do this by hand as the proffered address may not be correctly aligned.
182  * Subtraction of non-aligned pointers produces undefined results.
183  */
184 static unsigned long __meminit vmemmap_section_start(unsigned long page)
185 {
186 	unsigned long offset = page - ((unsigned long)(vmemmap));
187 
188 	/* Return the pfn of the start of the section. */
189 	return (offset / sizeof(struct page)) & PAGE_SECTION_MASK;
190 }
191 
192 /*
193  * Check if this vmemmap page is already initialised.  If any section
194  * which overlaps this vmemmap page is initialised then this page is
195  * initialised already.
196  */
197 static int __meminit vmemmap_populated(unsigned long start, int page_size)
198 {
199 	unsigned long end = start + page_size;
200 
201 	for (; start < end; start += (PAGES_PER_SECTION * sizeof(struct page)))
202 		if (pfn_valid(vmemmap_section_start(start)))
203 			return 1;
204 
205 	return 0;
206 }
207 
208 /* On hash-based CPUs, the vmemmap is bolted in the hash table.
209  *
210  * On Book3E CPUs, the vmemmap is currently mapped in the top half of
211  * the vmalloc space using normal page tables, though the size of
212  * pages encoded in the PTEs can be different
213  */
214 
215 #ifdef CONFIG_PPC_BOOK3E
216 static void __meminit vmemmap_create_mapping(unsigned long start,
217 					     unsigned long page_size,
218 					     unsigned long phys)
219 {
220 	/* Create a PTE encoding without page size */
221 	unsigned long i, flags = _PAGE_PRESENT | _PAGE_ACCESSED |
222 		_PAGE_KERNEL_RW;
223 
224 	/* PTEs only contain page size encodings up to 32M */
225 	BUG_ON(mmu_psize_defs[mmu_vmemmap_psize].enc > 0xf);
226 
227 	/* Encode the size in the PTE */
228 	flags |= mmu_psize_defs[mmu_vmemmap_psize].enc << 8;
229 
230 	/* For each PTE for that area, map things. Note that we don't
231 	 * increment phys because all PTEs are of the large size and
232 	 * thus must have the low bits clear
233 	 */
234 	for (i = 0; i < page_size; i += PAGE_SIZE)
235 		BUG_ON(map_kernel_page(start + i, phys, flags));
236 }
237 #else /* CONFIG_PPC_BOOK3E */
238 static void __meminit vmemmap_create_mapping(unsigned long start,
239 					     unsigned long page_size,
240 					     unsigned long phys)
241 {
242 	int  mapped = htab_bolt_mapping(start, start + page_size, phys,
243 					PAGE_KERNEL, mmu_vmemmap_psize,
244 					mmu_kernel_ssize);
245 	BUG_ON(mapped < 0);
246 }
247 #endif /* CONFIG_PPC_BOOK3E */
248 
249 int __meminit vmemmap_populate(struct page *start_page,
250 			       unsigned long nr_pages, int node)
251 {
252 	unsigned long start = (unsigned long)start_page;
253 	unsigned long end = (unsigned long)(start_page + nr_pages);
254 	unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
255 
256 	/* Align to the page size of the linear mapping. */
257 	start = _ALIGN_DOWN(start, page_size);
258 
259 	pr_debug("vmemmap_populate page %p, %ld pages, node %d\n",
260 		 start_page, nr_pages, node);
261 	pr_debug(" -> map %lx..%lx\n", start, end);
262 
263 	for (; start < end; start += page_size) {
264 		void *p;
265 
266 		if (vmemmap_populated(start, page_size))
267 			continue;
268 
269 		p = vmemmap_alloc_block(page_size, node);
270 		if (!p)
271 			return -ENOMEM;
272 
273 		pr_debug("      * %016lx..%016lx allocated at %p\n",
274 			 start, start + page_size, p);
275 
276 		vmemmap_create_mapping(start, page_size, __pa(p));
277 	}
278 
279 	return 0;
280 }
281 #endif /* CONFIG_SPARSEMEM_VMEMMAP */
282