xref: /linux/arch/powerpc/mm/init_64.c (revision 858259cf7d1c443c836a2022b78cb281f0a9b95e)
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  *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
9  *
10  *  Derived from "arch/i386/mm/init.c"
11  *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
12  *
13  *  Dave Engebretsen <engebret@us.ibm.com>
14  *      Rework for PPC64 port.
15  *
16  *  This program is free software; you can redistribute it and/or
17  *  modify it under the terms of the GNU General Public License
18  *  as published by the Free Software Foundation; either version
19  *  2 of the License, or (at your option) any later version.
20  *
21  */
22 
23 #include <linux/config.h>
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 
43 #include <asm/pgalloc.h>
44 #include <asm/page.h>
45 #include <asm/prom.h>
46 #include <asm/lmb.h>
47 #include <asm/rtas.h>
48 #include <asm/io.h>
49 #include <asm/mmu_context.h>
50 #include <asm/pgtable.h>
51 #include <asm/mmu.h>
52 #include <asm/uaccess.h>
53 #include <asm/smp.h>
54 #include <asm/machdep.h>
55 #include <asm/tlb.h>
56 #include <asm/eeh.h>
57 #include <asm/processor.h>
58 #include <asm/mmzone.h>
59 #include <asm/cputable.h>
60 #include <asm/ppcdebug.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 #include <asm/imalloc.h>
67 
68 #if PGTABLE_RANGE > USER_VSID_RANGE
69 #warning Limited user VSID range means pagetable space is wasted
70 #endif
71 
72 #if (TASK_SIZE_USER64 < PGTABLE_RANGE) && (TASK_SIZE_USER64 < USER_VSID_RANGE)
73 #warning TASK_SIZE is smaller than it needs to be.
74 #endif
75 
76 unsigned long klimit = (unsigned long)_end;
77 
78 /* max amount of RAM to use */
79 unsigned long __max_memory;
80 
81 /* info on what we think the IO hole is */
82 unsigned long 	io_hole_start;
83 unsigned long	io_hole_size;
84 
85 /*
86  * Do very early mm setup.
87  */
88 void __init mm_init_ppc64(void)
89 {
90 #ifndef CONFIG_PPC_ISERIES
91 	unsigned long i;
92 #endif
93 
94 	ppc64_boot_msg(0x100, "MM Init");
95 
96 	/* This is the story of the IO hole... please, keep seated,
97 	 * unfortunately, we are out of oxygen masks at the moment.
98 	 * So we need some rough way to tell where your big IO hole
99 	 * is. On pmac, it's between 2G and 4G, on POWER3, it's around
100 	 * that area as well, on POWER4 we don't have one, etc...
101 	 * We need that as a "hint" when sizing the TCE table on POWER3
102 	 * So far, the simplest way that seem work well enough for us it
103 	 * to just assume that the first discontinuity in our physical
104 	 * RAM layout is the IO hole. That may not be correct in the future
105 	 * (and isn't on iSeries but then we don't care ;)
106 	 */
107 
108 #ifndef CONFIG_PPC_ISERIES
109 	for (i = 1; i < lmb.memory.cnt; i++) {
110 		unsigned long base, prevbase, prevsize;
111 
112 		prevbase = lmb.memory.region[i-1].base;
113 		prevsize = lmb.memory.region[i-1].size;
114 		base = lmb.memory.region[i].base;
115 		if (base > (prevbase + prevsize)) {
116 			io_hole_start = prevbase + prevsize;
117 			io_hole_size = base  - (prevbase + prevsize);
118 			break;
119 		}
120 	}
121 #endif /* CONFIG_PPC_ISERIES */
122 	if (io_hole_start)
123 		printk("IO Hole assumed to be %lx -> %lx\n",
124 		       io_hole_start, io_hole_start + io_hole_size - 1);
125 
126 	ppc64_boot_msg(0x100, "MM Init Done");
127 }
128 
129 void free_initmem(void)
130 {
131 	unsigned long addr;
132 
133 	addr = (unsigned long)__init_begin;
134 	for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) {
135 		memset((void *)addr, 0xcc, PAGE_SIZE);
136 		ClearPageReserved(virt_to_page(addr));
137 		set_page_count(virt_to_page(addr), 1);
138 		free_page(addr);
139 		totalram_pages++;
140 	}
141 	printk ("Freeing unused kernel memory: %luk freed\n",
142 		((unsigned long)__init_end - (unsigned long)__init_begin) >> 10);
143 }
144 
145 #ifdef CONFIG_BLK_DEV_INITRD
146 void free_initrd_mem(unsigned long start, unsigned long end)
147 {
148 	if (start < end)
149 		printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
150 	for (; start < end; start += PAGE_SIZE) {
151 		ClearPageReserved(virt_to_page(start));
152 		set_page_count(virt_to_page(start), 1);
153 		free_page(start);
154 		totalram_pages++;
155 	}
156 }
157 #endif
158 
159 static struct kcore_list kcore_vmem;
160 
161 static int __init setup_kcore(void)
162 {
163 	int i;
164 
165 	for (i=0; i < lmb.memory.cnt; i++) {
166 		unsigned long base, size;
167 		struct kcore_list *kcore_mem;
168 
169 		base = lmb.memory.region[i].base;
170 		size = lmb.memory.region[i].size;
171 
172 		/* GFP_ATOMIC to avoid might_sleep warnings during boot */
173 		kcore_mem = kmalloc(sizeof(struct kcore_list), GFP_ATOMIC);
174 		if (!kcore_mem)
175 			panic("mem_init: kmalloc failed\n");
176 
177 		kclist_add(kcore_mem, __va(base), size);
178 	}
179 
180 	kclist_add(&kcore_vmem, (void *)VMALLOC_START, VMALLOC_END-VMALLOC_START);
181 
182 	return 0;
183 }
184 module_init(setup_kcore);
185 
186 static void zero_ctor(void *addr, kmem_cache_t *cache, unsigned long flags)
187 {
188 	memset(addr, 0, kmem_cache_size(cache));
189 }
190 
191 #ifdef CONFIG_PPC_64K_PAGES
192 static const int pgtable_cache_size[2] = {
193 	PTE_TABLE_SIZE, PGD_TABLE_SIZE
194 };
195 static const char *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
196 	"pte_pmd_cache", "pgd_cache",
197 };
198 #else
199 static const int pgtable_cache_size[2] = {
200 	PTE_TABLE_SIZE, PMD_TABLE_SIZE
201 };
202 static const char *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
203 	"pgd_pte_cache", "pud_pmd_cache",
204 };
205 #endif /* CONFIG_PPC_64K_PAGES */
206 
207 kmem_cache_t *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
208 
209 void pgtable_cache_init(void)
210 {
211 	int i;
212 
213 	for (i = 0; i < ARRAY_SIZE(pgtable_cache_size); i++) {
214 		int size = pgtable_cache_size[i];
215 		const char *name = pgtable_cache_name[i];
216 
217 		pgtable_cache[i] = kmem_cache_create(name,
218 						     size, size,
219 						     SLAB_HWCACHE_ALIGN |
220 						     SLAB_MUST_HWCACHE_ALIGN,
221 						     zero_ctor,
222 						     NULL);
223 		if (! pgtable_cache[i])
224 			panic("pgtable_cache_init(): could not create %s!\n",
225 			      name);
226 	}
227 }
228