xref: /openbmc/linux/arch/arm64/include/asm/memory.h (revision ca55b2fe)
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  * Size of the PCI I/O space. This must remain a power of two so that
37  * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
38  */
39 #define PCI_IO_SIZE		SZ_16M
40 
41 /*
42  * PAGE_OFFSET - the virtual address of the start of the kernel image (top
43  *		 (VA_BITS - 1))
44  * VA_BITS - the maximum number of bits for virtual addresses.
45  * TASK_SIZE - the maximum size of a user space task.
46  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
47  * The module space lives between the addresses given by TASK_SIZE
48  * and PAGE_OFFSET - it must be within 128MB of the kernel text.
49  */
50 #define VA_BITS			(CONFIG_ARM64_VA_BITS)
51 #define PAGE_OFFSET		(UL(0xffffffffffffffff) << (VA_BITS - 1))
52 #define MODULES_END		(PAGE_OFFSET)
53 #define MODULES_VADDR		(MODULES_END - SZ_64M)
54 #define PCI_IO_END		(MODULES_VADDR - SZ_2M)
55 #define PCI_IO_START		(PCI_IO_END - PCI_IO_SIZE)
56 #define FIXADDR_TOP		(PCI_IO_START - SZ_2M)
57 #define TASK_SIZE_64		(UL(1) << VA_BITS)
58 
59 #ifdef CONFIG_COMPAT
60 #define TASK_SIZE_32		UL(0x100000000)
61 #define TASK_SIZE		(test_thread_flag(TIF_32BIT) ? \
62 				TASK_SIZE_32 : TASK_SIZE_64)
63 #define TASK_SIZE_OF(tsk)	(test_tsk_thread_flag(tsk, TIF_32BIT) ? \
64 				TASK_SIZE_32 : TASK_SIZE_64)
65 #else
66 #define TASK_SIZE		TASK_SIZE_64
67 #endif /* CONFIG_COMPAT */
68 
69 #define TASK_UNMAPPED_BASE	(PAGE_ALIGN(TASK_SIZE / 4))
70 
71 #if TASK_SIZE_64 > MODULES_VADDR
72 #error Top of 64-bit user space clashes with start of module space
73 #endif
74 
75 /*
76  * Physical vs virtual RAM address space conversion.  These are
77  * private definitions which should NOT be used outside memory.h
78  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
79  */
80 #define __virt_to_phys(x)	(((phys_addr_t)(x) - PAGE_OFFSET + PHYS_OFFSET))
81 #define __phys_to_virt(x)	((unsigned long)((x) - PHYS_OFFSET + PAGE_OFFSET))
82 
83 /*
84  * Convert a page to/from a physical address
85  */
86 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
87 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
88 
89 /*
90  * Memory types available.
91  */
92 #define MT_DEVICE_nGnRnE	0
93 #define MT_DEVICE_nGnRE		1
94 #define MT_DEVICE_GRE		2
95 #define MT_NORMAL_NC		3
96 #define MT_NORMAL		4
97 
98 /*
99  * Memory types for Stage-2 translation
100  */
101 #define MT_S2_NORMAL		0xf
102 #define MT_S2_DEVICE_nGnRE	0x1
103 
104 #ifndef __ASSEMBLY__
105 
106 extern phys_addr_t		memstart_addr;
107 /* PHYS_OFFSET - the physical address of the start of memory. */
108 #define PHYS_OFFSET		({ memstart_addr; })
109 
110 /*
111  * The maximum physical address that the linear direct mapping
112  * of system RAM can cover. (PAGE_OFFSET can be interpreted as
113  * a 2's complement signed quantity and negated to derive the
114  * maximum size of the linear mapping.)
115  */
116 #define MAX_MEMBLOCK_ADDR	({ memstart_addr - PAGE_OFFSET - 1; })
117 
118 /*
119  * PFNs are used to describe any physical page; this means
120  * PFN 0 == physical address 0.
121  *
122  * This is the PFN of the first RAM page in the kernel
123  * direct-mapped view.  We assume this is the first page
124  * of RAM in the mem_map as well.
125  */
126 #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
127 
128 /*
129  * Note: Drivers should NOT use these.  They are the wrong
130  * translation for translating DMA addresses.  Use the driver
131  * DMA support - see dma-mapping.h.
132  */
133 #define virt_to_phys virt_to_phys
134 static inline phys_addr_t virt_to_phys(const volatile void *x)
135 {
136 	return __virt_to_phys((unsigned long)(x));
137 }
138 
139 #define phys_to_virt phys_to_virt
140 static inline void *phys_to_virt(phys_addr_t x)
141 {
142 	return (void *)(__phys_to_virt(x));
143 }
144 
145 /*
146  * Drivers should NOT use these either.
147  */
148 #define __pa(x)			__virt_to_phys((unsigned long)(x))
149 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
150 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
151 #define virt_to_pfn(x)      __phys_to_pfn(__virt_to_phys(x))
152 
153 /*
154  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
155  *  virt_addr_valid(k)	indicates whether a virtual address is valid
156  */
157 #define ARCH_PFN_OFFSET		((unsigned long)PHYS_PFN_OFFSET)
158 
159 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
160 #define	virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
161 
162 #endif
163 
164 #include <asm-generic/memory_model.h>
165 
166 #endif
167