xref: /openbmc/linux/arch/sh/mm/init.c (revision 9d56dd3b083a3bec56e9da35ce07baca81030b03)
1 /*
2  * linux/arch/sh/mm/init.c
3  *
4  *  Copyright (C) 1999  Niibe Yutaka
5  *  Copyright (C) 2002 - 2007  Paul Mundt
6  *
7  *  Based on linux/arch/i386/mm/init.c:
8  *   Copyright (C) 1995  Linus Torvalds
9  */
10 #include <linux/mm.h>
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>
17 #include <linux/io.h>
18 #include <linux/dma-mapping.h>
19 #include <asm/mmu_context.h>
20 #include <asm/tlb.h>
21 #include <asm/cacheflush.h>
22 #include <asm/sections.h>
23 #include <asm/cache.h>
24 
25 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
26 pgd_t swapper_pg_dir[PTRS_PER_PGD];
27 
28 #ifdef CONFIG_SUPERH32
29 /*
30  * This is the offset of the uncached section from its cached alias.
31  *
32  * Legacy platforms handle trivial transitions between cached and
33  * uncached segments by making use of the 1:1 mapping relationship in
34  * 512MB lowmem, others via a special uncached mapping.
35  *
36  * Default value only valid in 29 bit mode, in 32bit mode this will be
37  * updated by the early PMB initialization code.
38  */
39 unsigned long cached_to_uncached = P2SEG - P1SEG;
40 unsigned long uncached_size = 0x20000000;
41 #endif
42 
43 #ifdef CONFIG_MMU
44 static pte_t *__get_pte_phys(unsigned long addr)
45 {
46 	pgd_t *pgd;
47 	pud_t *pud;
48 	pmd_t *pmd;
49 	pte_t *pte;
50 
51 	pgd = pgd_offset_k(addr);
52 	if (pgd_none(*pgd)) {
53 		pgd_ERROR(*pgd);
54 		return NULL;
55 	}
56 
57 	pud = pud_alloc(NULL, pgd, addr);
58 	if (unlikely(!pud)) {
59 		pud_ERROR(*pud);
60 		return NULL;
61 	}
62 
63 	pmd = pmd_alloc(NULL, pud, addr);
64 	if (unlikely(!pmd)) {
65 		pmd_ERROR(*pmd);
66 		return NULL;
67 	}
68 
69 	pte = pte_offset_kernel(pmd, addr);
70 	return pte;
71 }
72 
73 static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
74 {
75 	pte_t *pte;
76 
77 	pte = __get_pte_phys(addr);
78 	if (!pte_none(*pte)) {
79 		pte_ERROR(*pte);
80 		return;
81 	}
82 
83 	set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
84 	local_flush_tlb_one(get_asid(), addr);
85 
86 	if (pgprot_val(prot) & _PAGE_WIRED)
87 		tlb_wire_entry(NULL, addr, *pte);
88 }
89 
90 static void clear_pte_phys(unsigned long addr, pgprot_t prot)
91 {
92 	pte_t *pte;
93 
94 	pte = __get_pte_phys(addr);
95 
96 	if (pgprot_val(prot) & _PAGE_WIRED)
97 		tlb_unwire_entry();
98 
99 	set_pte(pte, pfn_pte(0, __pgprot(0)));
100 	local_flush_tlb_one(get_asid(), addr);
101 }
102 
103 void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
104 {
105 	unsigned long address = __fix_to_virt(idx);
106 
107 	if (idx >= __end_of_fixed_addresses) {
108 		BUG();
109 		return;
110 	}
111 
112 	set_pte_phys(address, phys, prot);
113 }
114 
115 void __clear_fixmap(enum fixed_addresses idx, pgprot_t prot)
116 {
117 	unsigned long address = __fix_to_virt(idx);
118 
119 	if (idx >= __end_of_fixed_addresses) {
120 		BUG();
121 		return;
122 	}
123 
124 	clear_pte_phys(address, prot);
125 }
126 
127 void __init page_table_range_init(unsigned long start, unsigned long end,
128 					 pgd_t *pgd_base)
129 {
130 	pgd_t *pgd;
131 	pud_t *pud;
132 	pmd_t *pmd;
133 	pte_t *pte;
134 	int i, j, k;
135 	unsigned long vaddr;
136 
137 	vaddr = start;
138 	i = __pgd_offset(vaddr);
139 	j = __pud_offset(vaddr);
140 	k = __pmd_offset(vaddr);
141 	pgd = pgd_base + i;
142 
143 	for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
144 		pud = (pud_t *)pgd;
145 		for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
146 #ifdef __PAGETABLE_PMD_FOLDED
147 			pmd = (pmd_t *)pud;
148 #else
149 			pmd = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE);
150 			pud_populate(&init_mm, pud, pmd);
151 			pmd += k;
152 #endif
153 			for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
154 				if (pmd_none(*pmd)) {
155 					pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
156 					pmd_populate_kernel(&init_mm, pmd, pte);
157 					BUG_ON(pte != pte_offset_kernel(pmd, 0));
158 				}
159 				vaddr += PMD_SIZE;
160 			}
161 			k = 0;
162 		}
163 		j = 0;
164 	}
165 }
166 #endif	/* CONFIG_MMU */
167 
168 /*
169  * paging_init() sets up the page tables
170  */
171 void __init paging_init(void)
172 {
173 	unsigned long max_zone_pfns[MAX_NR_ZONES];
174 	unsigned long vaddr, end;
175 	int nid;
176 
177 	/* We don't need to map the kernel through the TLB, as
178 	 * it is permanatly mapped using P1. So clear the
179 	 * entire pgd. */
180 	memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
181 
182 	/* Set an initial value for the MMU.TTB so we don't have to
183 	 * check for a null value. */
184 	set_TTB(swapper_pg_dir);
185 
186 	/*
187 	 * Populate the relevant portions of swapper_pg_dir so that
188 	 * we can use the fixmap entries without calling kmalloc.
189 	 * pte's will be filled in by __set_fixmap().
190 	 */
191 	vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
192 	end = (FIXADDR_TOP + PMD_SIZE - 1) & PMD_MASK;
193 	page_table_range_init(vaddr, end, swapper_pg_dir);
194 
195 	kmap_coherent_init();
196 
197 	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
198 
199 	for_each_online_node(nid) {
200 		pg_data_t *pgdat = NODE_DATA(nid);
201 		unsigned long low, start_pfn;
202 
203 		start_pfn = pgdat->bdata->node_min_pfn;
204 		low = pgdat->bdata->node_low_pfn;
205 
206 		if (max_zone_pfns[ZONE_NORMAL] < low)
207 			max_zone_pfns[ZONE_NORMAL] = low;
208 
209 		printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
210 		       nid, start_pfn, low);
211 	}
212 
213 	free_area_init_nodes(max_zone_pfns);
214 }
215 
216 /*
217  * Early initialization for any I/O MMUs we might have.
218  */
219 static void __init iommu_init(void)
220 {
221 	no_iommu_init();
222 }
223 
224 unsigned int mem_init_done = 0;
225 
226 void __init mem_init(void)
227 {
228 	int codesize, datasize, initsize;
229 	int nid;
230 
231 	iommu_init();
232 
233 	num_physpages = 0;
234 	high_memory = NULL;
235 
236 	for_each_online_node(nid) {
237 		pg_data_t *pgdat = NODE_DATA(nid);
238 		unsigned long node_pages = 0;
239 		void *node_high_memory;
240 
241 		num_physpages += pgdat->node_present_pages;
242 
243 		if (pgdat->node_spanned_pages)
244 			node_pages = free_all_bootmem_node(pgdat);
245 
246 		totalram_pages += node_pages;
247 
248 		node_high_memory = (void *)__va((pgdat->node_start_pfn +
249 						 pgdat->node_spanned_pages) <<
250 						 PAGE_SHIFT);
251 		if (node_high_memory > high_memory)
252 			high_memory = node_high_memory;
253 	}
254 
255 	/* Set this up early, so we can take care of the zero page */
256 	cpu_cache_init();
257 
258 	/* clear the zero-page */
259 	memset(empty_zero_page, 0, PAGE_SIZE);
260 	__flush_wback_region(empty_zero_page, PAGE_SIZE);
261 
262 	/* Initialize the vDSO */
263 	vsyscall_init();
264 
265 	codesize =  (unsigned long) &_etext - (unsigned long) &_text;
266 	datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
267 	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
268 
269 	printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
270 	       "%dk data, %dk init)\n",
271 		nr_free_pages() << (PAGE_SHIFT-10),
272 		num_physpages << (PAGE_SHIFT-10),
273 		codesize >> 10,
274 		datasize >> 10,
275 		initsize >> 10);
276 
277 	printk(KERN_INFO "virtual kernel memory layout:\n"
278 		"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
279 #ifdef CONFIG_HIGHMEM
280 		"    pkmap   : 0x%08lx - 0x%08lx   (%4ld kB)\n"
281 #endif
282 		"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
283 		"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB) (cached)\n"
284 		"            : 0x%08lx - 0x%08lx   (%4ld MB) (uncached)\n"
285 		"      .init : 0x%08lx - 0x%08lx   (%4ld kB)\n"
286 		"      .data : 0x%08lx - 0x%08lx   (%4ld kB)\n"
287 		"      .text : 0x%08lx - 0x%08lx   (%4ld kB)\n",
288 		FIXADDR_START, FIXADDR_TOP,
289 		(FIXADDR_TOP - FIXADDR_START) >> 10,
290 
291 #ifdef CONFIG_HIGHMEM
292 		PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
293 		(LAST_PKMAP*PAGE_SIZE) >> 10,
294 #endif
295 
296 		(unsigned long)VMALLOC_START, VMALLOC_END,
297 		(VMALLOC_END - VMALLOC_START) >> 20,
298 
299 		(unsigned long)memory_start, (unsigned long)high_memory,
300 		((unsigned long)high_memory - (unsigned long)memory_start) >> 20,
301 
302 		(unsigned long)memory_start + cached_to_uncached,
303 		(unsigned long)memory_start + cached_to_uncached + uncached_size,
304 		uncached_size >> 20,
305 
306 		(unsigned long)&__init_begin, (unsigned long)&__init_end,
307 		((unsigned long)&__init_end -
308 		 (unsigned long)&__init_begin) >> 10,
309 
310 		(unsigned long)&_etext, (unsigned long)&_edata,
311 		((unsigned long)&_edata - (unsigned long)&_etext) >> 10,
312 
313 		(unsigned long)&_text, (unsigned long)&_etext,
314 		((unsigned long)&_etext - (unsigned long)&_text) >> 10);
315 
316 	mem_init_done = 1;
317 }
318 
319 void free_initmem(void)
320 {
321 	unsigned long addr;
322 
323 	addr = (unsigned long)(&__init_begin);
324 	for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
325 		ClearPageReserved(virt_to_page(addr));
326 		init_page_count(virt_to_page(addr));
327 		free_page(addr);
328 		totalram_pages++;
329 	}
330 	printk("Freeing unused kernel memory: %ldk freed\n",
331 	       ((unsigned long)&__init_end -
332 	        (unsigned long)&__init_begin) >> 10);
333 }
334 
335 #ifdef CONFIG_BLK_DEV_INITRD
336 void free_initrd_mem(unsigned long start, unsigned long end)
337 {
338 	unsigned long p;
339 	for (p = start; p < end; p += PAGE_SIZE) {
340 		ClearPageReserved(virt_to_page(p));
341 		init_page_count(virt_to_page(p));
342 		free_page(p);
343 		totalram_pages++;
344 	}
345 	printk("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
346 }
347 #endif
348 
349 #ifdef CONFIG_MEMORY_HOTPLUG
350 int arch_add_memory(int nid, u64 start, u64 size)
351 {
352 	pg_data_t *pgdat;
353 	unsigned long start_pfn = start >> PAGE_SHIFT;
354 	unsigned long nr_pages = size >> PAGE_SHIFT;
355 	int ret;
356 
357 	pgdat = NODE_DATA(nid);
358 
359 	/* We only have ZONE_NORMAL, so this is easy.. */
360 	ret = __add_pages(nid, pgdat->node_zones + ZONE_NORMAL,
361 				start_pfn, nr_pages);
362 	if (unlikely(ret))
363 		printk("%s: Failed, __add_pages() == %d\n", __func__, ret);
364 
365 	return ret;
366 }
367 EXPORT_SYMBOL_GPL(arch_add_memory);
368 
369 #ifdef CONFIG_NUMA
370 int memory_add_physaddr_to_nid(u64 addr)
371 {
372 	/* Node 0 for now.. */
373 	return 0;
374 }
375 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
376 #endif
377 
378 #endif /* CONFIG_MEMORY_HOTPLUG */
379