xref: /openbmc/linux/arch/ia64/mm/contig.c (revision be58f710)
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/efi.h>
18 #include <linux/memblock.h>
19 #include <linux/mm.h>
20 #include <linux/nmi.h>
21 #include <linux/swap.h>
22 #include <linux/sizes.h>
23 
24 #include <asm/efi.h>
25 #include <asm/meminit.h>
26 #include <asm/sections.h>
27 #include <asm/mca.h>
28 
29 /* physical address where the bootmem map is located */
30 unsigned long bootmap_start;
31 
32 #ifdef CONFIG_SMP
33 static void *cpu_data;
34 /**
35  * per_cpu_init - setup per-cpu variables
36  *
37  * Allocate and setup per-cpu data areas.
38  */
39 void *per_cpu_init(void)
40 {
41 	static bool first_time = true;
42 	void *cpu0_data = __cpu0_per_cpu;
43 	unsigned int cpu;
44 
45 	if (!first_time)
46 		goto skip;
47 	first_time = false;
48 
49 	/*
50 	 * get_free_pages() cannot be used before cpu_init() done.
51 	 * BSP allocates PERCPU_PAGE_SIZE bytes for all possible CPUs
52 	 * to avoid that AP calls get_zeroed_page().
53 	 */
54 	for_each_possible_cpu(cpu) {
55 		void *src = cpu == 0 ? cpu0_data : __phys_per_cpu_start;
56 
57 		memcpy(cpu_data, src, __per_cpu_end - __per_cpu_start);
58 		__per_cpu_offset[cpu] = (char *)cpu_data - __per_cpu_start;
59 		per_cpu(local_per_cpu_offset, cpu) = __per_cpu_offset[cpu];
60 
61 		/*
62 		 * percpu area for cpu0 is moved from the __init area
63 		 * which is setup by head.S and used till this point.
64 		 * Update ar.k3.  This move is ensures that percpu
65 		 * area for cpu0 is on the correct node and its
66 		 * virtual address isn't insanely far from other
67 		 * percpu areas which is important for congruent
68 		 * percpu allocator.
69 		 */
70 		if (cpu == 0)
71 			ia64_set_kr(IA64_KR_PER_CPU_DATA, __pa(cpu_data) -
72 				    (unsigned long)__per_cpu_start);
73 
74 		cpu_data += PERCPU_PAGE_SIZE;
75 	}
76 skip:
77 	return __per_cpu_start + __per_cpu_offset[smp_processor_id()];
78 }
79 
80 static inline void
81 alloc_per_cpu_data(void)
82 {
83 	size_t size = PERCPU_PAGE_SIZE * num_possible_cpus();
84 
85 	cpu_data = memblock_alloc_from(size, PERCPU_PAGE_SIZE,
86 				       __pa(MAX_DMA_ADDRESS));
87 	if (!cpu_data)
88 		panic("%s: Failed to allocate %lu bytes align=%lx from=%lx\n",
89 		      __func__, size, PERCPU_PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
90 }
91 
92 /**
93  * setup_per_cpu_areas - setup percpu areas
94  *
95  * Arch code has already allocated and initialized percpu areas.  All
96  * this function has to do is to teach the determined layout to the
97  * dynamic percpu allocator, which happens to be more complex than
98  * creating whole new ones using helpers.
99  */
100 void __init
101 setup_per_cpu_areas(void)
102 {
103 	struct pcpu_alloc_info *ai;
104 	struct pcpu_group_info *gi;
105 	unsigned int cpu;
106 	ssize_t static_size, reserved_size, dyn_size;
107 
108 	ai = pcpu_alloc_alloc_info(1, num_possible_cpus());
109 	if (!ai)
110 		panic("failed to allocate pcpu_alloc_info");
111 	gi = &ai->groups[0];
112 
113 	/* units are assigned consecutively to possible cpus */
114 	for_each_possible_cpu(cpu)
115 		gi->cpu_map[gi->nr_units++] = cpu;
116 
117 	/* set parameters */
118 	static_size = __per_cpu_end - __per_cpu_start;
119 	reserved_size = PERCPU_MODULE_RESERVE;
120 	dyn_size = PERCPU_PAGE_SIZE - static_size - reserved_size;
121 	if (dyn_size < 0)
122 		panic("percpu area overflow static=%zd reserved=%zd\n",
123 		      static_size, reserved_size);
124 
125 	ai->static_size		= static_size;
126 	ai->reserved_size	= reserved_size;
127 	ai->dyn_size		= dyn_size;
128 	ai->unit_size		= PERCPU_PAGE_SIZE;
129 	ai->atom_size		= PAGE_SIZE;
130 	ai->alloc_size		= PERCPU_PAGE_SIZE;
131 
132 	pcpu_setup_first_chunk(ai, __per_cpu_start + __per_cpu_offset[0]);
133 	pcpu_free_alloc_info(ai);
134 }
135 #else
136 #define alloc_per_cpu_data() do { } while (0)
137 #endif /* CONFIG_SMP */
138 
139 /**
140  * find_memory - setup memory map
141  *
142  * Walk the EFI memory map and find usable memory for the system, taking
143  * into account reserved areas.
144  */
145 void __init
146 find_memory (void)
147 {
148 	reserve_memory();
149 
150 	/* first find highest page frame number */
151 	min_low_pfn = ~0UL;
152 	max_low_pfn = 0;
153 	efi_memmap_walk(find_max_min_low_pfn, NULL);
154 	max_pfn = max_low_pfn;
155 
156 	memblock_add_node(0, PFN_PHYS(max_low_pfn), 0);
157 
158 	find_initrd();
159 
160 	alloc_per_cpu_data();
161 }
162 
163 static int __init find_largest_hole(u64 start, u64 end, void *arg)
164 {
165 	u64 *max_gap = arg;
166 
167 	static u64 last_end = PAGE_OFFSET;
168 
169 	/* NOTE: this algorithm assumes efi memmap table is ordered */
170 
171 	if (*max_gap < (start - last_end))
172 		*max_gap = start - last_end;
173 	last_end = end;
174 	return 0;
175 }
176 
177 static void __init verify_gap_absence(void)
178 {
179 	unsigned long max_gap;
180 
181 	/* Forbid FLATMEM if hole is > than 1G */
182 	efi_memmap_walk(find_largest_hole, (u64 *)&max_gap);
183 	if (max_gap >= SZ_1G)
184 		panic("Cannot use FLATMEM with %ldMB hole\n"
185 		      "Please switch over to SPARSEMEM\n",
186 		      (max_gap >> 20));
187 }
188 
189 /*
190  * Set up the page tables.
191  */
192 
193 void __init
194 paging_init (void)
195 {
196 	unsigned long max_dma;
197 	unsigned long max_zone_pfns[MAX_NR_ZONES];
198 
199 	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
200 	max_dma = virt_to_phys((void *) MAX_DMA_ADDRESS) >> PAGE_SHIFT;
201 	max_zone_pfns[ZONE_DMA32] = max_dma;
202 	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
203 
204 	verify_gap_absence();
205 
206 	free_area_init(max_zone_pfns);
207 	zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page));
208 }
209