xref: /openbmc/linux/arch/arm64/include/asm/memory.h (revision 1b39eacd)
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/bug.h>
28 #include <asm/page-def.h>
29 #include <asm/sizes.h>
30 
31 /*
32  * Allow for constants defined here to be used from assembly code
33  * by prepending the UL suffix only with actual C code compilation.
34  */
35 #define UL(x) _AC(x, UL)
36 
37 /*
38  * Size of the PCI I/O space. This must remain a power of two so that
39  * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
40  */
41 #define PCI_IO_SIZE		SZ_16M
42 
43 /*
44  * Log2 of the upper bound of the size of a struct page. Used for sizing
45  * the vmemmap region only, does not affect actual memory footprint.
46  * We don't use sizeof(struct page) directly since taking its size here
47  * requires its definition to be available at this point in the inclusion
48  * chain, and it may not be a power of 2 in the first place.
49  */
50 #define STRUCT_PAGE_MAX_SHIFT	6
51 
52 /*
53  * VMEMMAP_SIZE - allows the whole linear region to be covered by
54  *                a struct page array
55  */
56 #define VMEMMAP_SIZE (UL(1) << (VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT))
57 
58 /*
59  * PAGE_OFFSET - the virtual address of the start of the linear map (top
60  *		 (VA_BITS - 1))
61  * KIMAGE_VADDR - the virtual address of the start of the kernel image
62  * VA_BITS - the maximum number of bits for virtual addresses.
63  * VA_START - the first kernel virtual address.
64  */
65 #define VA_BITS			(CONFIG_ARM64_VA_BITS)
66 #define VA_START		(UL(0xffffffffffffffff) - \
67 	(UL(1) << VA_BITS) + 1)
68 #define PAGE_OFFSET		(UL(0xffffffffffffffff) - \
69 	(UL(1) << (VA_BITS - 1)) + 1)
70 #define KIMAGE_VADDR		(MODULES_END)
71 #define MODULES_END		(MODULES_VADDR + MODULES_VSIZE)
72 #define MODULES_VADDR		(VA_START + KASAN_SHADOW_SIZE)
73 #define MODULES_VSIZE		(SZ_128M)
74 #define VMEMMAP_START		(PAGE_OFFSET - VMEMMAP_SIZE)
75 #define PCI_IO_END		(VMEMMAP_START - SZ_2M)
76 #define PCI_IO_START		(PCI_IO_END - PCI_IO_SIZE)
77 #define FIXADDR_TOP		(PCI_IO_START - SZ_2M)
78 
79 #define KERNEL_START      _text
80 #define KERNEL_END        _end
81 
82 /*
83  * KASAN requires 1/8th of the kernel virtual address space for the shadow
84  * region. KASAN can bloat the stack significantly, so double the (minimum)
85  * stack size when KASAN is in use.
86  */
87 #ifdef CONFIG_KASAN
88 #define KASAN_SHADOW_SIZE	(UL(1) << (VA_BITS - 3))
89 #define KASAN_THREAD_SHIFT	1
90 #else
91 #define KASAN_SHADOW_SIZE	(0)
92 #define KASAN_THREAD_SHIFT	0
93 #endif
94 
95 #define MIN_THREAD_SHIFT	(14 + KASAN_THREAD_SHIFT)
96 
97 /*
98  * VMAP'd stacks are allocated at page granularity, so we must ensure that such
99  * stacks are a multiple of page size.
100  */
101 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
102 #define THREAD_SHIFT		PAGE_SHIFT
103 #else
104 #define THREAD_SHIFT		MIN_THREAD_SHIFT
105 #endif
106 
107 #if THREAD_SHIFT >= PAGE_SHIFT
108 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
109 #endif
110 
111 #define THREAD_SIZE		(UL(1) << THREAD_SHIFT)
112 
113 /*
114  * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
115  * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
116  * assembly.
117  */
118 #ifdef CONFIG_VMAP_STACK
119 #define THREAD_ALIGN		(2 * THREAD_SIZE)
120 #else
121 #define THREAD_ALIGN		THREAD_SIZE
122 #endif
123 
124 #define IRQ_STACK_SIZE		THREAD_SIZE
125 
126 #define OVERFLOW_STACK_SIZE	SZ_4K
127 
128 /*
129  * Alignment of kernel segments (e.g. .text, .data).
130  */
131 #if defined(CONFIG_DEBUG_ALIGN_RODATA)
132 /*
133  *  4 KB granule:   1 level 2 entry
134  * 16 KB granule: 128 level 3 entries, with contiguous bit
135  * 64 KB granule:  32 level 3 entries, with contiguous bit
136  */
137 #define SEGMENT_ALIGN			SZ_2M
138 #else
139 /*
140  *  4 KB granule:  16 level 3 entries, with contiguous bit
141  * 16 KB granule:   4 level 3 entries, without contiguous bit
142  * 64 KB granule:   1 level 3 entry
143  */
144 #define SEGMENT_ALIGN			SZ_64K
145 #endif
146 
147 /*
148  * Memory types available.
149  */
150 #define MT_DEVICE_nGnRnE	0
151 #define MT_DEVICE_nGnRE		1
152 #define MT_DEVICE_GRE		2
153 #define MT_NORMAL_NC		3
154 #define MT_NORMAL		4
155 #define MT_NORMAL_WT		5
156 
157 /*
158  * Memory types for Stage-2 translation
159  */
160 #define MT_S2_NORMAL		0xf
161 #define MT_S2_DEVICE_nGnRE	0x1
162 
163 #ifdef CONFIG_ARM64_4K_PAGES
164 #define IOREMAP_MAX_ORDER	(PUD_SHIFT)
165 #else
166 #define IOREMAP_MAX_ORDER	(PMD_SHIFT)
167 #endif
168 
169 #ifdef CONFIG_BLK_DEV_INITRD
170 #define __early_init_dt_declare_initrd(__start, __end)			\
171 	do {								\
172 		initrd_start = (__start);				\
173 		initrd_end = (__end);					\
174 	} while (0)
175 #endif
176 
177 #ifndef __ASSEMBLY__
178 
179 #include <linux/bitops.h>
180 #include <linux/mmdebug.h>
181 
182 extern s64			memstart_addr;
183 /* PHYS_OFFSET - the physical address of the start of memory. */
184 #define PHYS_OFFSET		({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
185 
186 /* the virtual base of the kernel image (minus TEXT_OFFSET) */
187 extern u64			kimage_vaddr;
188 
189 /* the offset between the kernel virtual and physical mappings */
190 extern u64			kimage_voffset;
191 
192 static inline unsigned long kaslr_offset(void)
193 {
194 	return kimage_vaddr - KIMAGE_VADDR;
195 }
196 
197 /*
198  * Allow all memory at the discovery stage. We will clip it later.
199  */
200 #define MIN_MEMBLOCK_ADDR	0
201 #define MAX_MEMBLOCK_ADDR	U64_MAX
202 
203 /*
204  * PFNs are used to describe any physical page; this means
205  * PFN 0 == physical address 0.
206  *
207  * This is the PFN of the first RAM page in the kernel
208  * direct-mapped view.  We assume this is the first page
209  * of RAM in the mem_map as well.
210  */
211 #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
212 
213 /*
214  * Physical vs virtual RAM address space conversion.  These are
215  * private definitions which should NOT be used outside memory.h
216  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
217  */
218 
219 
220 /*
221  * The linear kernel range starts in the middle of the virtual adddress
222  * space. Testing the top bit for the start of the region is a
223  * sufficient check.
224  */
225 #define __is_lm_address(addr)	(!!((addr) & BIT(VA_BITS - 1)))
226 
227 #define __lm_to_phys(addr)	(((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
228 #define __kimg_to_phys(addr)	((addr) - kimage_voffset)
229 
230 #define __virt_to_phys_nodebug(x) ({					\
231 	phys_addr_t __x = (phys_addr_t)(x);				\
232 	__is_lm_address(__x) ? __lm_to_phys(__x) :			\
233 			       __kimg_to_phys(__x);			\
234 })
235 
236 #define __pa_symbol_nodebug(x)	__kimg_to_phys((phys_addr_t)(x))
237 
238 #ifdef CONFIG_DEBUG_VIRTUAL
239 extern phys_addr_t __virt_to_phys(unsigned long x);
240 extern phys_addr_t __phys_addr_symbol(unsigned long x);
241 #else
242 #define __virt_to_phys(x)	__virt_to_phys_nodebug(x)
243 #define __phys_addr_symbol(x)	__pa_symbol_nodebug(x)
244 #endif
245 
246 #define __phys_to_virt(x)	((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
247 #define __phys_to_kimg(x)	((unsigned long)((x) + kimage_voffset))
248 
249 /*
250  * Convert a page to/from a physical address
251  */
252 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
253 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
254 
255 /*
256  * Note: Drivers should NOT use these.  They are the wrong
257  * translation for translating DMA addresses.  Use the driver
258  * DMA support - see dma-mapping.h.
259  */
260 #define virt_to_phys virt_to_phys
261 static inline phys_addr_t virt_to_phys(const volatile void *x)
262 {
263 	return __virt_to_phys((unsigned long)(x));
264 }
265 
266 #define phys_to_virt phys_to_virt
267 static inline void *phys_to_virt(phys_addr_t x)
268 {
269 	return (void *)(__phys_to_virt(x));
270 }
271 
272 /*
273  * Drivers should NOT use these either.
274  */
275 #define __pa(x)			__virt_to_phys((unsigned long)(x))
276 #define __pa_symbol(x)		__phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
277 #define __pa_nodebug(x)		__virt_to_phys_nodebug((unsigned long)(x))
278 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
279 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
280 #define virt_to_pfn(x)      __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
281 #define sym_to_pfn(x)	    __phys_to_pfn(__pa_symbol(x))
282 
283 /*
284  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
285  *  virt_addr_valid(k)	indicates whether a virtual address is valid
286  */
287 #define ARCH_PFN_OFFSET		((unsigned long)PHYS_PFN_OFFSET)
288 
289 #ifndef CONFIG_SPARSEMEM_VMEMMAP
290 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
291 #define _virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
292 #else
293 #define __virt_to_pgoff(kaddr)	(((u64)(kaddr) & ~PAGE_OFFSET) / PAGE_SIZE * sizeof(struct page))
294 #define __page_to_voff(kaddr)	(((u64)(kaddr) & ~VMEMMAP_START) * PAGE_SIZE / sizeof(struct page))
295 
296 #define page_to_virt(page)	((void *)((__page_to_voff(page)) | PAGE_OFFSET))
297 #define virt_to_page(vaddr)	((struct page *)((__virt_to_pgoff(vaddr)) | VMEMMAP_START))
298 
299 #define _virt_addr_valid(kaddr)	pfn_valid((((u64)(kaddr) & ~PAGE_OFFSET) \
300 					   + PHYS_OFFSET) >> PAGE_SHIFT)
301 #endif
302 #endif
303 
304 #define _virt_addr_is_linear(kaddr)	(((u64)(kaddr)) >= PAGE_OFFSET)
305 #define virt_addr_valid(kaddr)		(_virt_addr_is_linear(kaddr) && \
306 					 _virt_addr_valid(kaddr))
307 
308 #include <asm-generic/memory_model.h>
309 
310 #endif
311