xref: /openbmc/linux/arch/ia64/mm/contig.c (revision 87c2ce3b)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1998-2003 Hewlett-Packard Co
7  *	David Mosberger-Tang <davidm@hpl.hp.com>
8  *	Stephane Eranian <eranian@hpl.hp.com>
9  * Copyright (C) 2000, Rohit Seth <rohit.seth@intel.com>
10  * Copyright (C) 1999 VA Linux Systems
11  * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
12  * Copyright (C) 2003 Silicon Graphics, Inc. All rights reserved.
13  *
14  * Routines used by ia64 machines with contiguous (or virtually contiguous)
15  * memory.
16  */
17 #include <linux/config.h>
18 #include <linux/bootmem.h>
19 #include <linux/efi.h>
20 #include <linux/mm.h>
21 #include <linux/swap.h>
22 
23 #include <asm/meminit.h>
24 #include <asm/pgalloc.h>
25 #include <asm/pgtable.h>
26 #include <asm/sections.h>
27 #include <asm/mca.h>
28 
29 #ifdef CONFIG_VIRTUAL_MEM_MAP
30 static unsigned long num_dma_physpages;
31 #endif
32 
33 /**
34  * show_mem - display a memory statistics summary
35  *
36  * Just walks the pages in the system and describes where they're allocated.
37  */
38 void
39 show_mem (void)
40 {
41 	int i, total = 0, reserved = 0;
42 	int shared = 0, cached = 0;
43 
44 	printk("Mem-info:\n");
45 	show_free_areas();
46 
47 	printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
48 	i = max_mapnr;
49 	while (i-- > 0) {
50 		if (!pfn_valid(i))
51 			continue;
52 		total++;
53 		if (PageReserved(mem_map+i))
54 			reserved++;
55 		else if (PageSwapCache(mem_map+i))
56 			cached++;
57 		else if (page_count(mem_map + i))
58 			shared += page_count(mem_map + i) - 1;
59 	}
60 	printk("%d pages of RAM\n", total);
61 	printk("%d reserved pages\n", reserved);
62 	printk("%d pages shared\n", shared);
63 	printk("%d pages swap cached\n", cached);
64 	printk("%ld pages in page table cache\n",
65 		pgtable_quicklist_total_size());
66 }
67 
68 /* physical address where the bootmem map is located */
69 unsigned long bootmap_start;
70 
71 /**
72  * find_max_pfn - adjust the maximum page number callback
73  * @start: start of range
74  * @end: end of range
75  * @arg: address of pointer to global max_pfn variable
76  *
77  * Passed as a callback function to efi_memmap_walk() to determine the highest
78  * available page frame number in the system.
79  */
80 int
81 find_max_pfn (unsigned long start, unsigned long end, void *arg)
82 {
83 	unsigned long *max_pfnp = arg, pfn;
84 
85 	pfn = (PAGE_ALIGN(end - 1) - PAGE_OFFSET) >> PAGE_SHIFT;
86 	if (pfn > *max_pfnp)
87 		*max_pfnp = pfn;
88 	return 0;
89 }
90 
91 /**
92  * find_bootmap_location - callback to find a memory area for the bootmap
93  * @start: start of region
94  * @end: end of region
95  * @arg: unused callback data
96  *
97  * Find a place to put the bootmap and return its starting address in
98  * bootmap_start.  This address must be page-aligned.
99  */
100 int
101 find_bootmap_location (unsigned long start, unsigned long end, void *arg)
102 {
103 	unsigned long needed = *(unsigned long *)arg;
104 	unsigned long range_start, range_end, free_start;
105 	int i;
106 
107 #if IGNORE_PFN0
108 	if (start == PAGE_OFFSET) {
109 		start += PAGE_SIZE;
110 		if (start >= end)
111 			return 0;
112 	}
113 #endif
114 
115 	free_start = PAGE_OFFSET;
116 
117 	for (i = 0; i < num_rsvd_regions; i++) {
118 		range_start = max(start, free_start);
119 		range_end   = min(end, rsvd_region[i].start & PAGE_MASK);
120 
121 		free_start = PAGE_ALIGN(rsvd_region[i].end);
122 
123 		if (range_end <= range_start)
124 			continue; /* skip over empty range */
125 
126 		if (range_end - range_start >= needed) {
127 			bootmap_start = __pa(range_start);
128 			return -1;	/* done */
129 		}
130 
131 		/* nothing more available in this segment */
132 		if (range_end == end)
133 			return 0;
134 	}
135 	return 0;
136 }
137 
138 /**
139  * find_memory - setup memory map
140  *
141  * Walk the EFI memory map and find usable memory for the system, taking
142  * into account reserved areas.
143  */
144 void
145 find_memory (void)
146 {
147 	unsigned long bootmap_size;
148 
149 	reserve_memory();
150 
151 	/* first find highest page frame number */
152 	max_pfn = 0;
153 	efi_memmap_walk(find_max_pfn, &max_pfn);
154 
155 	/* how many bytes to cover all the pages */
156 	bootmap_size = bootmem_bootmap_pages(max_pfn) << PAGE_SHIFT;
157 
158 	/* look for a location to hold the bootmap */
159 	bootmap_start = ~0UL;
160 	efi_memmap_walk(find_bootmap_location, &bootmap_size);
161 	if (bootmap_start == ~0UL)
162 		panic("Cannot find %ld bytes for bootmap\n", bootmap_size);
163 
164 	bootmap_size = init_bootmem(bootmap_start >> PAGE_SHIFT, max_pfn);
165 
166 	/* Free all available memory, then mark bootmem-map as being in use. */
167 	efi_memmap_walk(filter_rsvd_memory, free_bootmem);
168 	reserve_bootmem(bootmap_start, bootmap_size);
169 
170 	find_initrd();
171 }
172 
173 #ifdef CONFIG_SMP
174 /**
175  * per_cpu_init - setup per-cpu variables
176  *
177  * Allocate and setup per-cpu data areas.
178  */
179 void *
180 per_cpu_init (void)
181 {
182 	void *cpu_data;
183 	int cpu;
184 
185 	/*
186 	 * get_free_pages() cannot be used before cpu_init() done.  BSP
187 	 * allocates "NR_CPUS" pages for all CPUs to avoid that AP calls
188 	 * get_zeroed_page().
189 	 */
190 	if (smp_processor_id() == 0) {
191 		cpu_data = __alloc_bootmem(PERCPU_PAGE_SIZE * NR_CPUS,
192 					   PERCPU_PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
193 		for (cpu = 0; cpu < NR_CPUS; cpu++) {
194 			memcpy(cpu_data, __phys_per_cpu_start, __per_cpu_end - __per_cpu_start);
195 			__per_cpu_offset[cpu] = (char *) cpu_data - __per_cpu_start;
196 			cpu_data += PERCPU_PAGE_SIZE;
197 			per_cpu(local_per_cpu_offset, cpu) = __per_cpu_offset[cpu];
198 		}
199 	}
200 	return __per_cpu_start + __per_cpu_offset[smp_processor_id()];
201 }
202 #endif /* CONFIG_SMP */
203 
204 static int
205 count_pages (u64 start, u64 end, void *arg)
206 {
207 	unsigned long *count = arg;
208 
209 	*count += (end - start) >> PAGE_SHIFT;
210 	return 0;
211 }
212 
213 #ifdef CONFIG_VIRTUAL_MEM_MAP
214 static int
215 count_dma_pages (u64 start, u64 end, void *arg)
216 {
217 	unsigned long *count = arg;
218 
219 	if (start < MAX_DMA_ADDRESS)
220 		*count += (min(end, MAX_DMA_ADDRESS) - start) >> PAGE_SHIFT;
221 	return 0;
222 }
223 #endif
224 
225 /*
226  * Set up the page tables.
227  */
228 
229 void
230 paging_init (void)
231 {
232 	unsigned long max_dma;
233 	unsigned long zones_size[MAX_NR_ZONES];
234 #ifdef CONFIG_VIRTUAL_MEM_MAP
235 	unsigned long zholes_size[MAX_NR_ZONES];
236 	unsigned long max_gap;
237 #endif
238 
239 	/* initialize mem_map[] */
240 
241 	memset(zones_size, 0, sizeof(zones_size));
242 
243 	num_physpages = 0;
244 	efi_memmap_walk(count_pages, &num_physpages);
245 
246 	max_dma = virt_to_phys((void *) MAX_DMA_ADDRESS) >> PAGE_SHIFT;
247 
248 #ifdef CONFIG_VIRTUAL_MEM_MAP
249 	memset(zholes_size, 0, sizeof(zholes_size));
250 
251 	num_dma_physpages = 0;
252 	efi_memmap_walk(count_dma_pages, &num_dma_physpages);
253 
254 	if (max_low_pfn < max_dma) {
255 		zones_size[ZONE_DMA] = max_low_pfn;
256 		zholes_size[ZONE_DMA] = max_low_pfn - num_dma_physpages;
257 	} else {
258 		zones_size[ZONE_DMA] = max_dma;
259 		zholes_size[ZONE_DMA] = max_dma - num_dma_physpages;
260 		if (num_physpages > num_dma_physpages) {
261 			zones_size[ZONE_NORMAL] = max_low_pfn - max_dma;
262 			zholes_size[ZONE_NORMAL] =
263 				((max_low_pfn - max_dma) -
264 				 (num_physpages - num_dma_physpages));
265 		}
266 	}
267 
268 	max_gap = 0;
269 	efi_memmap_walk(find_largest_hole, (u64 *)&max_gap);
270 	if (max_gap < LARGE_GAP) {
271 		vmem_map = (struct page *) 0;
272 		free_area_init_node(0, NODE_DATA(0), zones_size, 0,
273 				    zholes_size);
274 	} else {
275 		unsigned long map_size;
276 
277 		/* allocate virtual_mem_map */
278 
279 		map_size = PAGE_ALIGN(max_low_pfn * sizeof(struct page));
280 		vmalloc_end -= map_size;
281 		vmem_map = (struct page *) vmalloc_end;
282 		efi_memmap_walk(create_mem_map_page_table, NULL);
283 
284 		NODE_DATA(0)->node_mem_map = vmem_map;
285 		free_area_init_node(0, NODE_DATA(0), zones_size,
286 				    0, zholes_size);
287 
288 		printk("Virtual mem_map starts at 0x%p\n", mem_map);
289 	}
290 #else /* !CONFIG_VIRTUAL_MEM_MAP */
291 	if (max_low_pfn < max_dma)
292 		zones_size[ZONE_DMA] = max_low_pfn;
293 	else {
294 		zones_size[ZONE_DMA] = max_dma;
295 		zones_size[ZONE_NORMAL] = max_low_pfn - max_dma;
296 	}
297 	free_area_init(zones_size);
298 #endif /* !CONFIG_VIRTUAL_MEM_MAP */
299 	zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page));
300 }
301