xref: /openbmc/linux/arch/arm64/include/asm/memory.h (revision 82e6fdd6)
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_SCALE_SHIFT 3
89 #define KASAN_SHADOW_SIZE	(UL(1) << (VA_BITS - KASAN_SHADOW_SCALE_SHIFT))
90 #define KASAN_THREAD_SHIFT	1
91 #else
92 #define KASAN_SHADOW_SIZE	(0)
93 #define KASAN_THREAD_SHIFT	0
94 #endif
95 
96 #define MIN_THREAD_SHIFT	(14 + KASAN_THREAD_SHIFT)
97 
98 /*
99  * VMAP'd stacks are allocated at page granularity, so we must ensure that such
100  * stacks are a multiple of page size.
101  */
102 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
103 #define THREAD_SHIFT		PAGE_SHIFT
104 #else
105 #define THREAD_SHIFT		MIN_THREAD_SHIFT
106 #endif
107 
108 #if THREAD_SHIFT >= PAGE_SHIFT
109 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
110 #endif
111 
112 #define THREAD_SIZE		(UL(1) << THREAD_SHIFT)
113 
114 /*
115  * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
116  * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
117  * assembly.
118  */
119 #ifdef CONFIG_VMAP_STACK
120 #define THREAD_ALIGN		(2 * THREAD_SIZE)
121 #else
122 #define THREAD_ALIGN		THREAD_SIZE
123 #endif
124 
125 #define IRQ_STACK_SIZE		THREAD_SIZE
126 
127 #define OVERFLOW_STACK_SIZE	SZ_4K
128 
129 /*
130  * Alignment of kernel segments (e.g. .text, .data).
131  */
132 #if defined(CONFIG_DEBUG_ALIGN_RODATA)
133 /*
134  *  4 KB granule:   1 level 2 entry
135  * 16 KB granule: 128 level 3 entries, with contiguous bit
136  * 64 KB granule:  32 level 3 entries, with contiguous bit
137  */
138 #define SEGMENT_ALIGN			SZ_2M
139 #else
140 /*
141  *  4 KB granule:  16 level 3 entries, with contiguous bit
142  * 16 KB granule:   4 level 3 entries, without contiguous bit
143  * 64 KB granule:   1 level 3 entry
144  */
145 #define SEGMENT_ALIGN			SZ_64K
146 #endif
147 
148 /*
149  * Memory types available.
150  */
151 #define MT_DEVICE_nGnRnE	0
152 #define MT_DEVICE_nGnRE		1
153 #define MT_DEVICE_GRE		2
154 #define MT_NORMAL_NC		3
155 #define MT_NORMAL		4
156 #define MT_NORMAL_WT		5
157 
158 /*
159  * Memory types for Stage-2 translation
160  */
161 #define MT_S2_NORMAL		0xf
162 #define MT_S2_DEVICE_nGnRE	0x1
163 
164 #ifdef CONFIG_ARM64_4K_PAGES
165 #define IOREMAP_MAX_ORDER	(PUD_SHIFT)
166 #else
167 #define IOREMAP_MAX_ORDER	(PMD_SHIFT)
168 #endif
169 
170 #ifdef CONFIG_BLK_DEV_INITRD
171 #define __early_init_dt_declare_initrd(__start, __end)			\
172 	do {								\
173 		initrd_start = (__start);				\
174 		initrd_end = (__end);					\
175 	} while (0)
176 #endif
177 
178 #ifndef __ASSEMBLY__
179 
180 #include <linux/bitops.h>
181 #include <linux/mmdebug.h>
182 
183 extern s64			memstart_addr;
184 /* PHYS_OFFSET - the physical address of the start of memory. */
185 #define PHYS_OFFSET		({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
186 
187 /* the virtual base of the kernel image (minus TEXT_OFFSET) */
188 extern u64			kimage_vaddr;
189 
190 /* the offset between the kernel virtual and physical mappings */
191 extern u64			kimage_voffset;
192 
193 static inline unsigned long kaslr_offset(void)
194 {
195 	return kimage_vaddr - KIMAGE_VADDR;
196 }
197 
198 /*
199  * Allow all memory at the discovery stage. We will clip it later.
200  */
201 #define MIN_MEMBLOCK_ADDR	0
202 #define MAX_MEMBLOCK_ADDR	U64_MAX
203 
204 /*
205  * PFNs are used to describe any physical page; this means
206  * PFN 0 == physical address 0.
207  *
208  * This is the PFN of the first RAM page in the kernel
209  * direct-mapped view.  We assume this is the first page
210  * of RAM in the mem_map as well.
211  */
212 #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
213 
214 /*
215  * Physical vs virtual RAM address space conversion.  These are
216  * private definitions which should NOT be used outside memory.h
217  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
218  */
219 
220 
221 /*
222  * The linear kernel range starts in the middle of the virtual adddress
223  * space. Testing the top bit for the start of the region is a
224  * sufficient check.
225  */
226 #define __is_lm_address(addr)	(!!((addr) & BIT(VA_BITS - 1)))
227 
228 #define __lm_to_phys(addr)	(((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
229 #define __kimg_to_phys(addr)	((addr) - kimage_voffset)
230 
231 #define __virt_to_phys_nodebug(x) ({					\
232 	phys_addr_t __x = (phys_addr_t)(x);				\
233 	__is_lm_address(__x) ? __lm_to_phys(__x) :			\
234 			       __kimg_to_phys(__x);			\
235 })
236 
237 #define __pa_symbol_nodebug(x)	__kimg_to_phys((phys_addr_t)(x))
238 
239 #ifdef CONFIG_DEBUG_VIRTUAL
240 extern phys_addr_t __virt_to_phys(unsigned long x);
241 extern phys_addr_t __phys_addr_symbol(unsigned long x);
242 #else
243 #define __virt_to_phys(x)	__virt_to_phys_nodebug(x)
244 #define __phys_addr_symbol(x)	__pa_symbol_nodebug(x)
245 #endif
246 
247 #define __phys_to_virt(x)	((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
248 #define __phys_to_kimg(x)	((unsigned long)((x) + kimage_voffset))
249 
250 /*
251  * Convert a page to/from a physical address
252  */
253 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
254 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
255 
256 /*
257  * Note: Drivers should NOT use these.  They are the wrong
258  * translation for translating DMA addresses.  Use the driver
259  * DMA support - see dma-mapping.h.
260  */
261 #define virt_to_phys virt_to_phys
262 static inline phys_addr_t virt_to_phys(const volatile void *x)
263 {
264 	return __virt_to_phys((unsigned long)(x));
265 }
266 
267 #define phys_to_virt phys_to_virt
268 static inline void *phys_to_virt(phys_addr_t x)
269 {
270 	return (void *)(__phys_to_virt(x));
271 }
272 
273 /*
274  * Drivers should NOT use these either.
275  */
276 #define __pa(x)			__virt_to_phys((unsigned long)(x))
277 #define __pa_symbol(x)		__phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
278 #define __pa_nodebug(x)		__virt_to_phys_nodebug((unsigned long)(x))
279 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
280 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
281 #define virt_to_pfn(x)      __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
282 #define sym_to_pfn(x)	    __phys_to_pfn(__pa_symbol(x))
283 
284 /*
285  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
286  *  virt_addr_valid(k)	indicates whether a virtual address is valid
287  */
288 #define ARCH_PFN_OFFSET		((unsigned long)PHYS_PFN_OFFSET)
289 
290 #ifndef CONFIG_SPARSEMEM_VMEMMAP
291 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
292 #define _virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
293 #else
294 #define __virt_to_pgoff(kaddr)	(((u64)(kaddr) & ~PAGE_OFFSET) / PAGE_SIZE * sizeof(struct page))
295 #define __page_to_voff(kaddr)	(((u64)(kaddr) & ~VMEMMAP_START) * PAGE_SIZE / sizeof(struct page))
296 
297 #define page_to_virt(page)	((void *)((__page_to_voff(page)) | PAGE_OFFSET))
298 #define virt_to_page(vaddr)	((struct page *)((__virt_to_pgoff(vaddr)) | VMEMMAP_START))
299 
300 #define _virt_addr_valid(kaddr)	pfn_valid((((u64)(kaddr) & ~PAGE_OFFSET) \
301 					   + PHYS_OFFSET) >> PAGE_SHIFT)
302 #endif
303 #endif
304 
305 #define _virt_addr_is_linear(kaddr)	(((u64)(kaddr)) >= PAGE_OFFSET)
306 #define virt_addr_valid(kaddr)		(_virt_addr_is_linear(kaddr) && \
307 					 _virt_addr_valid(kaddr))
308 
309 #include <asm-generic/memory_model.h>
310 
311 #endif
312