2 * linux/arch/sh/mm/init.c
4 * Copyright (C) 1999 Niibe Yutaka
5 * Copyright (C) 2002 - 2007 Paul Mundt
7 * Based on linux/arch/i386/mm/init.c:
8 * Copyright (C) 1995 Linus Torvalds
11 #include <linux/swap.h>
12 #include <linux/init.h>
13 #include <linux/bootmem.h>
14 #include <linux/proc_fs.h>
15 #include <linux/pagemap.h>
16 #include <linux/percpu.h>
18 #include <asm/mmu_context.h>
20 #include <asm/cacheflush.h>
21 #include <asm/sections.h>
22 #include <asm/cache.h>
24 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
25 pgd_t swapper_pg_dir[PTRS_PER_PGD];
27 #ifdef CONFIG_SUPERH32
29 * Handle trivial transitions between cached and uncached
30 * segments, making use of the 1:1 mapping relationship in
33 * This is the offset of the uncached section from its cached alias.
34 * Default value only valid in 29 bit mode, in 32bit mode will be
35 * overridden in pmb_init.
37 unsigned long cached_to_uncached = P2SEG - P1SEG;
41 static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
48 pgd = pgd_offset_k(addr);
54 pud = pud_alloc(NULL, pgd, addr);
60 pmd = pmd_alloc(NULL, pud, addr);
66 pte = pte_offset_kernel(pmd, addr);
67 if (!pte_none(*pte)) {
72 set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
73 flush_tlb_one(get_asid(), addr);
77 * As a performance optimization, other platforms preserve the fixmap mapping
78 * across a context switch, we don't presently do this, but this could be done
79 * in a similar fashion as to the wired TLB interface that sh64 uses (by way
80 * of the memory mapped UTLB configuration) -- this unfortunately forces us to
81 * give up a TLB entry for each mapping we want to preserve. While this may be
82 * viable for a small number of fixmaps, it's not particularly useful for
83 * everything and needs to be carefully evaluated. (ie, we may want this for
86 * XXX: Perhaps add a _PAGE_WIRED flag or something similar that we can pass
87 * in at __set_fixmap() time to determine the appropriate behavior to follow.
91 void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
93 unsigned long address = __fix_to_virt(idx);
95 if (idx >= __end_of_fixed_addresses) {
100 set_pte_phys(address, phys, prot);
103 void __init page_table_range_init(unsigned long start, unsigned long end,
112 vaddr = start & PMD_MASK;
113 end = (end + PMD_SIZE - 1) & PMD_MASK;
114 pgd_idx = pgd_index(vaddr);
115 pgd = pgd_base + pgd_idx;
117 for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd++, pgd_idx++) {
118 BUG_ON(pgd_none(*pgd));
119 pud = pud_offset(pgd, 0);
120 BUG_ON(pud_none(*pud));
121 pmd = pmd_offset(pud, 0);
123 if (!pmd_present(*pmd)) {
125 pte_table = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
126 memset(pte_table, 0, PAGE_SIZE);
127 pmd_populate_kernel(&init_mm, pmd, pte_table);
133 #endif /* CONFIG_MMU */
136 * paging_init() sets up the page tables
138 void __init paging_init(void)
140 unsigned long max_zone_pfns[MAX_NR_ZONES];
143 /* We don't need to map the kernel through the TLB, as
144 * it is permanatly mapped using P1. So clear the
146 memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
148 /* Set an initial value for the MMU.TTB so we don't have to
149 * check for a null value. */
150 set_TTB(swapper_pg_dir);
152 /* Populate the relevant portions of swapper_pg_dir so that
153 * we can use the fixmap entries without calling kmalloc.
154 * pte's will be filled in by __set_fixmap(). */
155 page_table_range_init(FIXADDR_START, FIXADDR_TOP, swapper_pg_dir);
157 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
159 for_each_online_node(nid) {
160 pg_data_t *pgdat = NODE_DATA(nid);
161 unsigned long low, start_pfn;
163 start_pfn = pgdat->bdata->node_min_pfn;
164 low = pgdat->bdata->node_low_pfn;
166 if (max_zone_pfns[ZONE_NORMAL] < low)
167 max_zone_pfns[ZONE_NORMAL] = low;
169 printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
170 nid, start_pfn, low);
173 free_area_init_nodes(max_zone_pfns);
175 #ifdef CONFIG_SUPERH32
176 /* Set up the uncached fixmap */
177 set_fixmap_nocache(FIX_UNCACHED, __pa(&__uncached_start));
181 static struct kcore_list kcore_mem, kcore_vmalloc;
182 int after_bootmem = 0;
184 void __init mem_init(void)
186 int codesize, datasize, initsize;
192 for_each_online_node(nid) {
193 pg_data_t *pgdat = NODE_DATA(nid);
194 unsigned long node_pages = 0;
195 void *node_high_memory;
197 num_physpages += pgdat->node_present_pages;
199 if (pgdat->node_spanned_pages)
200 node_pages = free_all_bootmem_node(pgdat);
202 totalram_pages += node_pages;
204 node_high_memory = (void *)__va((pgdat->node_start_pfn +
205 pgdat->node_spanned_pages) <<
207 if (node_high_memory > high_memory)
208 high_memory = node_high_memory;
211 /* clear the zero-page */
212 memset(empty_zero_page, 0, PAGE_SIZE);
213 __flush_wback_region(empty_zero_page, PAGE_SIZE);
217 codesize = (unsigned long) &_etext - (unsigned long) &_text;
218 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
219 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
221 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
222 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
223 VMALLOC_END - VMALLOC_START);
225 printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
226 "%dk data, %dk init)\n",
227 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
228 num_physpages << (PAGE_SHIFT-10),
235 /* Initialize the vDSO */
239 void free_initmem(void)
243 addr = (unsigned long)(&__init_begin);
244 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
245 ClearPageReserved(virt_to_page(addr));
246 init_page_count(virt_to_page(addr));
250 printk("Freeing unused kernel memory: %ldk freed\n",
251 ((unsigned long)&__init_end -
252 (unsigned long)&__init_begin) >> 10);
255 #ifdef CONFIG_BLK_DEV_INITRD
256 void free_initrd_mem(unsigned long start, unsigned long end)
259 for (p = start; p < end; p += PAGE_SIZE) {
260 ClearPageReserved(virt_to_page(p));
261 init_page_count(virt_to_page(p));
265 printk("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
269 #ifdef CONFIG_MEMORY_HOTPLUG
270 int arch_add_memory(int nid, u64 start, u64 size)
273 unsigned long start_pfn = start >> PAGE_SHIFT;
274 unsigned long nr_pages = size >> PAGE_SHIFT;
277 pgdat = NODE_DATA(nid);
279 /* We only have ZONE_NORMAL, so this is easy.. */
280 ret = __add_pages(pgdat->node_zones + ZONE_NORMAL, start_pfn, nr_pages);
282 printk("%s: Failed, __add_pages() == %d\n", __func__, ret);
286 EXPORT_SYMBOL_GPL(arch_add_memory);
289 int memory_add_physaddr_to_nid(u64 addr)
291 /* Node 0 for now.. */
294 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
297 #ifdef CONFIG_MEMORY_HOTREMOVE
298 int remove_memory(u64 start, u64 size)
300 unsigned long start_pfn = start >> PAGE_SHIFT;
301 unsigned long end_pfn = start_pfn + (size >> PAGE_SHIFT);
304 ret = offline_pages(start_pfn, end_pfn, 120 * HZ);
306 printk("%s: Failed, offline_pages() == %d\n", __func__, ret);
310 EXPORT_SYMBOL_GPL(remove_memory);
313 #endif /* CONFIG_MEMORY_HOTPLUG */