1/*
2 * Based on arch/arm/include/asm/memory.h
3 *
4 * Copyright (C) 2000-2002 Russell King
5 * Copyright (C) 2012 ARM Ltd.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18 *
19 * Note: this file should not be included by non-asm/.h files
20 */
21#ifndef __ASM_MEMORY_H
22#define __ASM_MEMORY_H
23
24#include <linux/compiler.h>
25#include <linux/const.h>
26#include <linux/types.h>
27#include <asm/sizes.h>
28
29/*
30 * Allow for constants defined here to be used from assembly code
31 * by prepending the UL suffix only with actual C code compilation.
32 */
33#define UL(x) _AC(x, UL)
34
35/*
36 * PAGE_OFFSET - the virtual address of the start of the kernel image (top
37 *		 (VA_BITS - 1))
38 * VA_BITS - the maximum number of bits for virtual addresses.
39 * TASK_SIZE - the maximum size of a user space task.
40 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
41 * The module space lives between the addresses given by TASK_SIZE
42 * and PAGE_OFFSET - it must be within 128MB of the kernel text.
43 */
44#define VA_BITS			(CONFIG_ARM64_VA_BITS)
45#define PAGE_OFFSET		(UL(0xffffffffffffffff) << (VA_BITS - 1))
46#define MODULES_END		(PAGE_OFFSET)
47#define MODULES_VADDR		(MODULES_END - SZ_64M)
48#define FIXADDR_TOP		(MODULES_VADDR - SZ_2M - PAGE_SIZE)
49#define TASK_SIZE_64		(UL(1) << VA_BITS)
50
51#ifdef CONFIG_COMPAT
52#define TASK_SIZE_32		UL(0x100000000)
53#define TASK_SIZE		(test_thread_flag(TIF_32BIT) ? \
54				TASK_SIZE_32 : TASK_SIZE_64)
55#define TASK_SIZE_OF(tsk)	(test_tsk_thread_flag(tsk, TIF_32BIT) ? \
56				TASK_SIZE_32 : TASK_SIZE_64)
57#else
58#define TASK_SIZE		TASK_SIZE_64
59#endif /* CONFIG_COMPAT */
60
61#define TASK_UNMAPPED_BASE	(PAGE_ALIGN(TASK_SIZE / 4))
62
63#if TASK_SIZE_64 > MODULES_VADDR
64#error Top of 64-bit user space clashes with start of module space
65#endif
66
67/*
68 * Physical vs virtual RAM address space conversion.  These are
69 * private definitions which should NOT be used outside memory.h
70 * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
71 */
72#define __virt_to_phys(x)	(((phys_addr_t)(x) - PAGE_OFFSET + PHYS_OFFSET))
73#define __phys_to_virt(x)	((unsigned long)((x) - PHYS_OFFSET + PAGE_OFFSET))
74
75/*
76 * Convert a physical address to a Page Frame Number and back
77 */
78#define	__phys_to_pfn(paddr)	((unsigned long)((paddr) >> PAGE_SHIFT))
79#define	__pfn_to_phys(pfn)	((phys_addr_t)(pfn) << PAGE_SHIFT)
80
81/*
82 * Convert a page to/from a physical address
83 */
84#define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
85#define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
86
87/*
88 * Memory types available.
89 */
90#define MT_DEVICE_nGnRnE	0
91#define MT_DEVICE_nGnRE		1
92#define MT_DEVICE_GRE		2
93#define MT_NORMAL_NC		3
94#define MT_NORMAL		4
95
96/*
97 * Memory types for Stage-2 translation
98 */
99#define MT_S2_NORMAL		0xf
100#define MT_S2_DEVICE_nGnRE	0x1
101
102#ifndef __ASSEMBLY__
103
104extern phys_addr_t		memstart_addr;
105/* PHYS_OFFSET - the physical address of the start of memory. */
106#define PHYS_OFFSET		({ memstart_addr; })
107
108/*
109 * PFNs are used to describe any physical page; this means
110 * PFN 0 == physical address 0.
111 *
112 * This is the PFN of the first RAM page in the kernel
113 * direct-mapped view.  We assume this is the first page
114 * of RAM in the mem_map as well.
115 */
116#define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
117
118/*
119 * Note: Drivers should NOT use these.  They are the wrong
120 * translation for translating DMA addresses.  Use the driver
121 * DMA support - see dma-mapping.h.
122 */
123static inline phys_addr_t virt_to_phys(const volatile void *x)
124{
125	return __virt_to_phys((unsigned long)(x));
126}
127
128static inline void *phys_to_virt(phys_addr_t x)
129{
130	return (void *)(__phys_to_virt(x));
131}
132
133/*
134 * Drivers should NOT use these either.
135 */
136#define __pa(x)			__virt_to_phys((unsigned long)(x))
137#define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
138#define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
139#define virt_to_pfn(x)      __phys_to_pfn(__virt_to_phys(x))
140
141/*
142 *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
143 *  virt_addr_valid(k)	indicates whether a virtual address is valid
144 */
145#define ARCH_PFN_OFFSET		((unsigned long)PHYS_PFN_OFFSET)
146
147#define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
148#define	virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
149
150#endif
151
152#include <asm-generic/memory_model.h>
153
154#endif
155