xref: /openbmc/linux/arch/arm64/include/asm/memory.h (revision 48c926cd)
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  * TASK_SIZE - the maximum size of a user space task.
65  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
66  */
67 #define VA_BITS			(CONFIG_ARM64_VA_BITS)
68 #define VA_START		(UL(0xffffffffffffffff) - \
69 	(UL(1) << VA_BITS) + 1)
70 #define PAGE_OFFSET		(UL(0xffffffffffffffff) - \
71 	(UL(1) << (VA_BITS - 1)) + 1)
72 #define KIMAGE_VADDR		(MODULES_END)
73 #define MODULES_END		(MODULES_VADDR + MODULES_VSIZE)
74 #define MODULES_VADDR		(VA_START + KASAN_SHADOW_SIZE)
75 #define MODULES_VSIZE		(SZ_128M)
76 #define VMEMMAP_START		(PAGE_OFFSET - VMEMMAP_SIZE)
77 #define PCI_IO_END		(VMEMMAP_START - SZ_2M)
78 #define PCI_IO_START		(PCI_IO_END - PCI_IO_SIZE)
79 #define FIXADDR_TOP		(PCI_IO_START - SZ_2M)
80 #define TASK_SIZE_64		(UL(1) << VA_BITS)
81 
82 #ifdef CONFIG_COMPAT
83 #define TASK_SIZE_32		UL(0x100000000)
84 #define TASK_SIZE		(test_thread_flag(TIF_32BIT) ? \
85 				TASK_SIZE_32 : TASK_SIZE_64)
86 #define TASK_SIZE_OF(tsk)	(test_tsk_thread_flag(tsk, TIF_32BIT) ? \
87 				TASK_SIZE_32 : TASK_SIZE_64)
88 #else
89 #define TASK_SIZE		TASK_SIZE_64
90 #endif /* CONFIG_COMPAT */
91 
92 #define TASK_UNMAPPED_BASE	(PAGE_ALIGN(TASK_SIZE / 4))
93 
94 #define KERNEL_START      _text
95 #define KERNEL_END        _end
96 
97 /*
98  * The size of the KASAN shadow region. This should be 1/8th of the
99  * size of the entire kernel virtual address space.
100  */
101 #ifdef CONFIG_KASAN
102 #define KASAN_SHADOW_SIZE	(UL(1) << (VA_BITS - 3))
103 #else
104 #define KASAN_SHADOW_SIZE	(0)
105 #endif
106 
107 #define MIN_THREAD_SHIFT	14
108 
109 /*
110  * VMAP'd stacks are allocated at page granularity, so we must ensure that such
111  * stacks are a multiple of page size.
112  */
113 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
114 #define THREAD_SHIFT		PAGE_SHIFT
115 #else
116 #define THREAD_SHIFT		MIN_THREAD_SHIFT
117 #endif
118 
119 #if THREAD_SHIFT >= PAGE_SHIFT
120 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
121 #endif
122 
123 #define THREAD_SIZE		(UL(1) << THREAD_SHIFT)
124 
125 /*
126  * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
127  * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
128  * assembly.
129  */
130 #ifdef CONFIG_VMAP_STACK
131 #define THREAD_ALIGN		(2 * THREAD_SIZE)
132 #else
133 #define THREAD_ALIGN		THREAD_SIZE
134 #endif
135 
136 #define IRQ_STACK_SIZE		THREAD_SIZE
137 
138 #define OVERFLOW_STACK_SIZE	SZ_4K
139 
140 /*
141  * Alignment of kernel segments (e.g. .text, .data).
142  */
143 #if defined(CONFIG_DEBUG_ALIGN_RODATA)
144 /*
145  *  4 KB granule:   1 level 2 entry
146  * 16 KB granule: 128 level 3 entries, with contiguous bit
147  * 64 KB granule:  32 level 3 entries, with contiguous bit
148  */
149 #define SEGMENT_ALIGN			SZ_2M
150 #else
151 /*
152  *  4 KB granule:  16 level 3 entries, with contiguous bit
153  * 16 KB granule:   4 level 3 entries, without contiguous bit
154  * 64 KB granule:   1 level 3 entry
155  */
156 #define SEGMENT_ALIGN			SZ_64K
157 #endif
158 
159 /*
160  * Memory types available.
161  */
162 #define MT_DEVICE_nGnRnE	0
163 #define MT_DEVICE_nGnRE		1
164 #define MT_DEVICE_GRE		2
165 #define MT_NORMAL_NC		3
166 #define MT_NORMAL		4
167 #define MT_NORMAL_WT		5
168 
169 /*
170  * Memory types for Stage-2 translation
171  */
172 #define MT_S2_NORMAL		0xf
173 #define MT_S2_DEVICE_nGnRE	0x1
174 
175 #ifdef CONFIG_ARM64_4K_PAGES
176 #define IOREMAP_MAX_ORDER	(PUD_SHIFT)
177 #else
178 #define IOREMAP_MAX_ORDER	(PMD_SHIFT)
179 #endif
180 
181 #ifdef CONFIG_BLK_DEV_INITRD
182 #define __early_init_dt_declare_initrd(__start, __end)			\
183 	do {								\
184 		initrd_start = (__start);				\
185 		initrd_end = (__end);					\
186 	} while (0)
187 #endif
188 
189 #ifndef __ASSEMBLY__
190 
191 #include <linux/bitops.h>
192 #include <linux/mmdebug.h>
193 
194 extern s64			memstart_addr;
195 /* PHYS_OFFSET - the physical address of the start of memory. */
196 #define PHYS_OFFSET		({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
197 
198 /* the virtual base of the kernel image (minus TEXT_OFFSET) */
199 extern u64			kimage_vaddr;
200 
201 /* the offset between the kernel virtual and physical mappings */
202 extern u64			kimage_voffset;
203 
204 static inline unsigned long kaslr_offset(void)
205 {
206 	return kimage_vaddr - KIMAGE_VADDR;
207 }
208 
209 /*
210  * Allow all memory at the discovery stage. We will clip it later.
211  */
212 #define MIN_MEMBLOCK_ADDR	0
213 #define MAX_MEMBLOCK_ADDR	U64_MAX
214 
215 /*
216  * PFNs are used to describe any physical page; this means
217  * PFN 0 == physical address 0.
218  *
219  * This is the PFN of the first RAM page in the kernel
220  * direct-mapped view.  We assume this is the first page
221  * of RAM in the mem_map as well.
222  */
223 #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
224 
225 /*
226  * Physical vs virtual RAM address space conversion.  These are
227  * private definitions which should NOT be used outside memory.h
228  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
229  */
230 
231 
232 /*
233  * The linear kernel range starts in the middle of the virtual adddress
234  * space. Testing the top bit for the start of the region is a
235  * sufficient check.
236  */
237 #define __is_lm_address(addr)	(!!((addr) & BIT(VA_BITS - 1)))
238 
239 #define __lm_to_phys(addr)	(((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
240 #define __kimg_to_phys(addr)	((addr) - kimage_voffset)
241 
242 #define __virt_to_phys_nodebug(x) ({					\
243 	phys_addr_t __x = (phys_addr_t)(x);				\
244 	__is_lm_address(__x) ? __lm_to_phys(__x) :			\
245 			       __kimg_to_phys(__x);			\
246 })
247 
248 #define __pa_symbol_nodebug(x)	__kimg_to_phys((phys_addr_t)(x))
249 
250 #ifdef CONFIG_DEBUG_VIRTUAL
251 extern phys_addr_t __virt_to_phys(unsigned long x);
252 extern phys_addr_t __phys_addr_symbol(unsigned long x);
253 #else
254 #define __virt_to_phys(x)	__virt_to_phys_nodebug(x)
255 #define __phys_addr_symbol(x)	__pa_symbol_nodebug(x)
256 #endif
257 
258 #define __phys_to_virt(x)	((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
259 #define __phys_to_kimg(x)	((unsigned long)((x) + kimage_voffset))
260 
261 /*
262  * Convert a page to/from a physical address
263  */
264 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
265 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
266 
267 /*
268  * Note: Drivers should NOT use these.  They are the wrong
269  * translation for translating DMA addresses.  Use the driver
270  * DMA support - see dma-mapping.h.
271  */
272 #define virt_to_phys virt_to_phys
273 static inline phys_addr_t virt_to_phys(const volatile void *x)
274 {
275 	return __virt_to_phys((unsigned long)(x));
276 }
277 
278 #define phys_to_virt phys_to_virt
279 static inline void *phys_to_virt(phys_addr_t x)
280 {
281 	return (void *)(__phys_to_virt(x));
282 }
283 
284 /*
285  * Drivers should NOT use these either.
286  */
287 #define __pa(x)			__virt_to_phys((unsigned long)(x))
288 #define __pa_symbol(x)		__phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
289 #define __pa_nodebug(x)		__virt_to_phys_nodebug((unsigned long)(x))
290 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
291 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
292 #define virt_to_pfn(x)      __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
293 #define sym_to_pfn(x)	    __phys_to_pfn(__pa_symbol(x))
294 
295 /*
296  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
297  *  virt_addr_valid(k)	indicates whether a virtual address is valid
298  */
299 #define ARCH_PFN_OFFSET		((unsigned long)PHYS_PFN_OFFSET)
300 
301 #ifndef CONFIG_SPARSEMEM_VMEMMAP
302 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
303 #define _virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
304 #else
305 #define __virt_to_pgoff(kaddr)	(((u64)(kaddr) & ~PAGE_OFFSET) / PAGE_SIZE * sizeof(struct page))
306 #define __page_to_voff(kaddr)	(((u64)(kaddr) & ~VMEMMAP_START) * PAGE_SIZE / sizeof(struct page))
307 
308 #define page_to_virt(page)	((void *)((__page_to_voff(page)) | PAGE_OFFSET))
309 #define virt_to_page(vaddr)	((struct page *)((__virt_to_pgoff(vaddr)) | VMEMMAP_START))
310 
311 #define _virt_addr_valid(kaddr)	pfn_valid((((u64)(kaddr) & ~PAGE_OFFSET) \
312 					   + PHYS_OFFSET) >> PAGE_SHIFT)
313 #endif
314 #endif
315 
316 #define _virt_addr_is_linear(kaddr)	(((u64)(kaddr)) >= PAGE_OFFSET)
317 #define virt_addr_valid(kaddr)		(_virt_addr_is_linear(kaddr) && \
318 					 _virt_addr_valid(kaddr))
319 
320 #include <asm-generic/memory_model.h>
321 
322 #endif
323