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/dma-map-ops.h>
11#include <linux/memblock.h>
12#include <linux/init.h>
13#include <linux/kernel.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/slab.h>
19#include <linux/swap.h>
20#include <linux/export.h>
21
22#include <asm/page.h>
23#include <asm/mmu_context.h>
24#include <asm/pgalloc.h>
25#include <asm/sections.h>
26#include <asm/tlb.h>
27#include <asm/fixmap.h>
28
29/* Use for MMU and noMMU because of PCI generic code */
30int mem_init_done;
31
32#ifndef CONFIG_MMU
33unsigned int __page_offset;
34EXPORT_SYMBOL(__page_offset);
35#endif /* CONFIG_MMU */
36
37char *klimit = _end;
38
39/*
40 * Initialize the bootmem system and give it all the memory we
41 * have available.
42 */
43unsigned long memory_start;
44EXPORT_SYMBOL(memory_start);
45unsigned long memory_size;
46EXPORT_SYMBOL(memory_size);
47unsigned long lowmem_size;
48
49EXPORT_SYMBOL(min_low_pfn);
50EXPORT_SYMBOL(max_low_pfn);
51
52#ifdef CONFIG_HIGHMEM
53pte_t *kmap_pte;
54EXPORT_SYMBOL(kmap_pte);
55
56static void __init highmem_init(void)
57{
58	pr_debug("%x\n", (u32)PKMAP_BASE);
59	map_page(PKMAP_BASE, 0, 0);	/* XXX gross */
60	pkmap_page_table = virt_to_kpte(PKMAP_BASE);
61
62	kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
63}
64
65static void highmem_setup(void)
66{
67	unsigned long pfn;
68
69	for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) {
70		struct page *page = pfn_to_page(pfn);
71
72		/* FIXME not sure about */
73		if (!memblock_is_reserved(pfn << PAGE_SHIFT))
74			free_highmem_page(page);
75	}
76}
77#endif /* CONFIG_HIGHMEM */
78
79/*
80 * paging_init() sets up the page tables - in fact we've already done this.
81 */
82static void __init paging_init(void)
83{
84	unsigned long zones_size[MAX_NR_ZONES];
85#ifdef CONFIG_MMU
86	int idx;
87
88	/* Setup fixmaps */
89	for (idx = 0; idx < __end_of_fixed_addresses; idx++)
90		clear_fixmap(idx);
91#endif
92
93	/* Clean every zones */
94	memset(zones_size, 0, sizeof(zones_size));
95
96#ifdef CONFIG_HIGHMEM
97	highmem_init();
98
99	zones_size[ZONE_DMA] = max_low_pfn;
100	zones_size[ZONE_HIGHMEM] = max_pfn;
101#else
102	zones_size[ZONE_DMA] = max_pfn;
103#endif
104
105	/* We don't have holes in memory map */
106	free_area_init(zones_size);
107}
108
109void __init setup_memory(void)
110{
111#ifndef CONFIG_MMU
112	u32 kernel_align_start, kernel_align_size;
113	phys_addr_t start, end;
114	u64 i;
115
116	/* Find main memory where is the kernel */
117	for_each_mem_range(i, &start, &end) {
118		memory_start = start;
119		lowmem_size = end - start;
120		if ((memory_start <= (u32)_text) &&
121			((u32)_text <= (memory_start + lowmem_size - 1))) {
122			memory_size = lowmem_size;
123			PAGE_OFFSET = memory_start;
124			pr_info("%s: Main mem: 0x%x, size 0x%08x\n",
125				__func__, (u32) memory_start,
126					(u32) memory_size);
127			break;
128		}
129	}
130
131	if (!memory_start || !memory_size) {
132		panic("%s: Missing memory setting 0x%08x, size=0x%08x\n",
133			__func__, (u32) memory_start, (u32) memory_size);
134	}
135
136	/* reservation of region where is the kernel */
137	kernel_align_start = PAGE_DOWN((u32)_text);
138	/* ALIGN can be remove because _end in vmlinux.lds.S is align */
139	kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
140	pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n",
141		__func__, kernel_align_start, kernel_align_start
142			+ kernel_align_size, kernel_align_size);
143	memblock_reserve(kernel_align_start, kernel_align_size);
144#endif
145	/*
146	 * Kernel:
147	 * start: base phys address of kernel - page align
148	 * end: base phys address of kernel - page align
149	 *
150	 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
151	 * max_low_pfn
152	 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
153	 */
154
155	/* memory start is from the kernel end (aligned) to higher addr */
156	min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
157	/* RAM is assumed contiguous */
158	max_mapnr = memory_size >> PAGE_SHIFT;
159	max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT;
160	max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT;
161
162	pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr);
163	pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
164	pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
165	pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn);
166
167	paging_init();
168}
169
170void __init mem_init(void)
171{
172	high_memory = (void *)__va(memory_start + lowmem_size - 1);
173
174	/* this will put all memory onto the freelists */
175	memblock_free_all();
176#ifdef CONFIG_HIGHMEM
177	highmem_setup();
178#endif
179
180	mem_init_print_info(NULL);
181	mem_init_done = 1;
182}
183
184#ifndef CONFIG_MMU
185int page_is_ram(unsigned long pfn)
186{
187	return __range_ok(pfn, 0);
188}
189#else
190int page_is_ram(unsigned long pfn)
191{
192	return pfn < max_low_pfn;
193}
194
195/*
196 * Check for command-line options that affect what MMU_init will do.
197 */
198static void mm_cmdline_setup(void)
199{
200	unsigned long maxmem = 0;
201	char *p = cmd_line;
202
203	/* Look for mem= option on command line */
204	p = strstr(cmd_line, "mem=");
205	if (p) {
206		p += 4;
207		maxmem = memparse(p, &p);
208		if (maxmem && memory_size > maxmem) {
209			memory_size = maxmem;
210			memblock.memory.regions[0].size = memory_size;
211		}
212	}
213}
214
215/*
216 * MMU_init_hw does the chip-specific initialization of the MMU hardware.
217 */
218static void __init mmu_init_hw(void)
219{
220	/*
221	 * The Zone Protection Register (ZPR) defines how protection will
222	 * be applied to every page which is a member of a given zone. At
223	 * present, we utilize only two of the zones.
224	 * The zone index bits (of ZSEL) in the PTE are used for software
225	 * indicators, except the LSB.  For user access, zone 1 is used,
226	 * for kernel access, zone 0 is used.  We set all but zone 1
227	 * to zero, allowing only kernel access as indicated in the PTE.
228	 * For zone 1, we set a 01 binary (a value of 10 will not work)
229	 * to allow user access as indicated in the PTE.  This also allows
230	 * kernel access as indicated in the PTE.
231	 */
232	__asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
233			"mts rzpr, r11;"
234			: : : "r11");
235}
236
237/*
238 * MMU_init sets up the basic memory mappings for the kernel,
239 * including both RAM and possibly some I/O regions,
240 * and sets up the page tables and the MMU hardware ready to go.
241 */
242
243/* called from head.S */
244asmlinkage void __init mmu_init(void)
245{
246	unsigned int kstart, ksize;
247
248	if (!memblock.reserved.cnt) {
249		pr_emerg("Error memory count\n");
250		machine_restart(NULL);
251	}
252
253	if ((u32) memblock.memory.regions[0].size < 0x400000) {
254		pr_emerg("Memory must be greater than 4MB\n");
255		machine_restart(NULL);
256	}
257
258	if ((u32) memblock.memory.regions[0].size < kernel_tlb) {
259		pr_emerg("Kernel size is greater than memory node\n");
260		machine_restart(NULL);
261	}
262
263	/* Find main memory where the kernel is */
264	memory_start = (u32) memblock.memory.regions[0].base;
265	lowmem_size = memory_size = (u32) memblock.memory.regions[0].size;
266
267	if (lowmem_size > CONFIG_LOWMEM_SIZE) {
268		lowmem_size = CONFIG_LOWMEM_SIZE;
269#ifndef CONFIG_HIGHMEM
270		memory_size = lowmem_size;
271#endif
272	}
273
274	mm_cmdline_setup(); /* FIXME parse args from command line - not used */
275
276	/*
277	 * Map out the kernel text/data/bss from the available physical
278	 * memory.
279	 */
280	kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
281	/* kernel size */
282	ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
283	memblock_reserve(kstart, ksize);
284
285#if defined(CONFIG_BLK_DEV_INITRD)
286	/* Remove the init RAM disk from the available memory. */
287	if (initrd_start) {
288		unsigned long size;
289		size = initrd_end - initrd_start;
290		memblock_reserve(__virt_to_phys(initrd_start), size);
291	}
292#endif /* CONFIG_BLK_DEV_INITRD */
293
294	/* Initialize the MMU hardware */
295	mmu_init_hw();
296
297	/* Map in all of RAM starting at CONFIG_KERNEL_START */
298	mapin_ram();
299
300	/* Extend vmalloc and ioremap area as big as possible */
301#ifdef CONFIG_HIGHMEM
302	ioremap_base = ioremap_bot = PKMAP_BASE;
303#else
304	ioremap_base = ioremap_bot = FIXADDR_START;
305#endif
306
307	/* Initialize the context management stuff */
308	mmu_context_init();
309
310	/* Shortly after that, the entire linear mapping will be available */
311	/* This will also cause that unflatten device tree will be allocated
312	 * inside 768MB limit */
313	memblock_set_current_limit(memory_start + lowmem_size - 1);
314
315	parse_early_param();
316
317	/* CMA initialization */
318	dma_contiguous_reserve(memory_start + lowmem_size - 1);
319}
320
321/* This is only called until mem_init is done. */
322void __init *early_get_page(void)
323{
324	/*
325	 * Mem start + kernel_tlb -> here is limit
326	 * because of mem mapping from head.S
327	 */
328	return memblock_alloc_try_nid_raw(PAGE_SIZE, PAGE_SIZE,
329				MEMBLOCK_LOW_LIMIT, memory_start + kernel_tlb,
330				NUMA_NO_NODE);
331}
332
333#endif /* CONFIG_MMU */
334
335void * __ref zalloc_maybe_bootmem(size_t size, gfp_t mask)
336{
337	void *p;
338
339	if (mem_init_done) {
340		p = kzalloc(size, mask);
341	} else {
342		p = memblock_alloc(size, SMP_CACHE_BYTES);
343		if (!p)
344			panic("%s: Failed to allocate %zu bytes\n",
345			      __func__, size);
346	}
347
348	return p;
349}
350