xref: /kernel/linux/linux-6.6/arch/ia64/mm/contig.c (revision 62306a36)
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 */
30unsigned long bootmap_start;
31
32#ifdef CONFIG_SMP
33static void *cpu_data;
34/**
35 * per_cpu_init - setup per-cpu variables
36 *
37 * Allocate and setup per-cpu data areas.
38 */
39void *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	}
76skip:
77	return __per_cpu_start + __per_cpu_offset[smp_processor_id()];
78}
79
80static inline __init void
81alloc_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 */
100void __init
101setup_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 */
145void __init
146find_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, MEMBLOCK_NONE);
157
158	find_initrd();
159
160	alloc_per_cpu_data();
161}
162
163static 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
177static 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
193void __init
194paging_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