init.c

  1/*
  2 * arch/xtensa/mm/init.c
  3 *
  4 * Derived from MIPS, PPC.
  5 *
  6 * This file is subject to the terms and conditions of the GNU General Public
  7 * License.  See the file "COPYING" in the main directory of this archive
  8 * for more details.
  9 *
 10 * Copyright (C) 2001 - 2005 Tensilica Inc.
 11 * Copyright (C) 2014 - 2016 Cadence Design Systems Inc.
 12 *
 13 * Chris Zankel	<chris@zankel.net>
 14 * Joe Taylor	<joe@tensilica.com, joetylr@yahoo.com>
 15 * Marc Gauthier
 16 * Kevin Chea
 17 */
 18
 19#include <linux/kernel.h>
 20#include <linux/errno.h>
 21#include <linux/memblock.h>
 22#include <linux/gfp.h>
 23#include <linux/highmem.h>
 24#include <linux/swap.h>
 25#include <linux/mman.h>
 26#include <linux/nodemask.h>
 27#include <linux/mm.h>
 28#include <linux/of_fdt.h>
 29#include <linux/dma-map-ops.h>
 30
 31#include <asm/bootparam.h>
 32#include <asm/page.h>
 33#include <asm/sections.h>
 34#include <asm/sysmem.h>
 35
 36/*
 37 * Initialize the bootmem system and give it all low memory we have available.
 38 */
 39
 40void __init bootmem_init(void)
 41{
 42	/* Reserve all memory below PHYS_OFFSET, as memory
 43	 * accounting doesn't work for pages below that address.
 44	 *
 45	 * If PHYS_OFFSET is zero reserve page at address 0:
 46	 * successfull allocations should never return NULL.
 47	 */
 48	memblock_reserve(0, PHYS_OFFSET ? PHYS_OFFSET : 1);
 49
 50	early_init_fdt_scan_reserved_mem();
 51
 52	if (!memblock_phys_mem_size())
 53		panic("No memory found!\n");
 54
 55	min_low_pfn = PFN_UP(memblock_start_of_DRAM());
 56	min_low_pfn = max(min_low_pfn, PFN_UP(PHYS_OFFSET));
 57	max_pfn = PFN_DOWN(memblock_end_of_DRAM());
 58	max_low_pfn = min(max_pfn, MAX_LOW_PFN);
 59
 60	early_memtest((phys_addr_t)min_low_pfn << PAGE_SHIFT,
 61		      (phys_addr_t)max_low_pfn << PAGE_SHIFT);
 62
 63	memblock_set_current_limit(PFN_PHYS(max_low_pfn));
 64	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
 65
 66	memblock_dump_all();
 67}
 68
 69static void __init print_vm_layout(void)
 70{
 71	pr_info("virtual kernel memory layout:\n"
 72#ifdef CONFIG_KASAN
 73		"    kasan   : 0x%08lx - 0x%08lx  (%5lu MB)\n"
 74#endif
 75#ifdef CONFIG_MMU
 76		"    vmalloc : 0x%08lx - 0x%08lx  (%5lu MB)\n"
 77#endif
 78#ifdef CONFIG_HIGHMEM
 79		"    pkmap   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
 80		"    fixmap  : 0x%08lx - 0x%08lx  (%5lu kB)\n"
 81#endif
 82		"    lowmem  : 0x%08lx - 0x%08lx  (%5lu MB)\n"
 83		"    .text   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
 84		"    .rodata : 0x%08lx - 0x%08lx  (%5lu kB)\n"
 85		"    .data   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
 86		"    .init   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
 87		"    .bss    : 0x%08lx - 0x%08lx  (%5lu kB)\n",
 88#ifdef CONFIG_KASAN
 89		KASAN_SHADOW_START, KASAN_SHADOW_START + KASAN_SHADOW_SIZE,
 90		KASAN_SHADOW_SIZE >> 20,
 91#endif
 92#ifdef CONFIG_MMU
 93		VMALLOC_START, VMALLOC_END,
 94		(VMALLOC_END - VMALLOC_START) >> 20,
 95#ifdef CONFIG_HIGHMEM
 96		PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE,
 97		(LAST_PKMAP*PAGE_SIZE) >> 10,
 98		FIXADDR_START, FIXADDR_END,
 99		(FIXADDR_END - FIXADDR_START) >> 10,
100#endif
101		PAGE_OFFSET, PAGE_OFFSET +
102		(max_low_pfn - min_low_pfn) * PAGE_SIZE,
103#else
104		min_low_pfn * PAGE_SIZE, max_low_pfn * PAGE_SIZE,
105#endif
106		((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20,
107		(unsigned long)_text, (unsigned long)_etext,
108		(unsigned long)(_etext - _text) >> 10,
109		(unsigned long)__start_rodata, (unsigned long)__end_rodata,
110		(unsigned long)(__end_rodata - __start_rodata) >> 10,
111		(unsigned long)_sdata, (unsigned long)_edata,
112		(unsigned long)(_edata - _sdata) >> 10,
113		(unsigned long)__init_begin, (unsigned long)__init_end,
114		(unsigned long)(__init_end - __init_begin) >> 10,
115		(unsigned long)__bss_start, (unsigned long)__bss_stop,
116		(unsigned long)(__bss_stop - __bss_start) >> 10);
117}
118
119void __init zones_init(void)
120{
121	/* All pages are DMA-able, so we put them all in the DMA zone. */
122	unsigned long max_zone_pfn[MAX_NR_ZONES] = {
123		[ZONE_NORMAL] = max_low_pfn,
124#ifdef CONFIG_HIGHMEM
125		[ZONE_HIGHMEM] = max_pfn,
126#endif
127	};
128	free_area_init(max_zone_pfn);
129	print_vm_layout();
130}
131
132static void __init parse_memmap_one(char *p)
133{
134	char *oldp;
135	unsigned long start_at, mem_size;
136
137	if (!p)
138		return;
139
140	oldp = p;
141	mem_size = memparse(p, &p);
142	if (p == oldp)
143		return;
144
145	switch (*p) {
146	case '@':
147		start_at = memparse(p + 1, &p);
148		memblock_add(start_at, mem_size);
149		break;
150
151	case '$':
152		start_at = memparse(p + 1, &p);
153		memblock_reserve(start_at, mem_size);
154		break;
155
156	case 0:
157		memblock_reserve(mem_size, -mem_size);
158		break;
159
160	default:
161		pr_warn("Unrecognized memmap syntax: %s\n", p);
162		break;
163	}
164}
165
166static int __init parse_memmap_opt(char *str)
167{
168	while (str) {
169		char *k = strchr(str, ',');
170
171		if (k)
172			*k++ = 0;
173
174		parse_memmap_one(str);
175		str = k;
176	}
177
178	return 0;
179}
180early_param("memmap", parse_memmap_opt);
181
182#ifdef CONFIG_MMU
183static const pgprot_t protection_map[16] = {
184	[VM_NONE]					= PAGE_NONE,
185	[VM_READ]					= PAGE_READONLY,
186	[VM_WRITE]					= PAGE_COPY,
187	[VM_WRITE | VM_READ]				= PAGE_COPY,
188	[VM_EXEC]					= PAGE_READONLY_EXEC,
189	[VM_EXEC | VM_READ]				= PAGE_READONLY_EXEC,
190	[VM_EXEC | VM_WRITE]				= PAGE_COPY_EXEC,
191	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_COPY_EXEC,
192	[VM_SHARED]					= PAGE_NONE,
193	[VM_SHARED | VM_READ]				= PAGE_READONLY,
194	[VM_SHARED | VM_WRITE]				= PAGE_SHARED,
195	[VM_SHARED | VM_WRITE | VM_READ]		= PAGE_SHARED,
196	[VM_SHARED | VM_EXEC]				= PAGE_READONLY_EXEC,
197	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_READONLY_EXEC,
198	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_SHARED_EXEC,
199	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_SHARED_EXEC
200};
201DECLARE_VM_GET_PAGE_PROT
202#endif