xref: /openbmc/linux/arch/arm64/include/asm/memory.h (revision 036b9e7c)
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  * Size of the PCI I/O space. This must remain a power of two so that
33  * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
34  */
35 #define PCI_IO_SIZE		SZ_16M
36 
37 /*
38  * Log2 of the upper bound of the size of a struct page. Used for sizing
39  * the vmemmap region only, does not affect actual memory footprint.
40  * We don't use sizeof(struct page) directly since taking its size here
41  * requires its definition to be available at this point in the inclusion
42  * chain, and it may not be a power of 2 in the first place.
43  */
44 #define STRUCT_PAGE_MAX_SHIFT	6
45 
46 /*
47  * VMEMMAP_SIZE - allows the whole linear region to be covered by
48  *                a struct page array
49  */
50 #define VMEMMAP_SIZE (UL(1) << (VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT))
51 
52 /*
53  * PAGE_OFFSET - the virtual address of the start of the linear map (top
54  *		 (VA_BITS - 1))
55  * KIMAGE_VADDR - the virtual address of the start of the kernel image
56  * VA_BITS - the maximum number of bits for virtual addresses.
57  * VA_START - the first kernel virtual address.
58  */
59 #define VA_BITS			(CONFIG_ARM64_VA_BITS)
60 #define VA_START		(UL(0xffffffffffffffff) - \
61 	(UL(1) << VA_BITS) + 1)
62 #define PAGE_OFFSET		(UL(0xffffffffffffffff) - \
63 	(UL(1) << (VA_BITS - 1)) + 1)
64 #define KIMAGE_VADDR		(MODULES_END)
65 #define BPF_JIT_REGION_START	(VA_START + KASAN_SHADOW_SIZE)
66 #define BPF_JIT_REGION_SIZE	(SZ_128M)
67 #define BPF_JIT_REGION_END	(BPF_JIT_REGION_START + BPF_JIT_REGION_SIZE)
68 #define MODULES_END		(MODULES_VADDR + MODULES_VSIZE)
69 #define MODULES_VADDR		(BPF_JIT_REGION_END)
70 #define MODULES_VSIZE		(SZ_128M)
71 #define VMEMMAP_START		(PAGE_OFFSET - VMEMMAP_SIZE)
72 #define PCI_IO_END		(VMEMMAP_START - SZ_2M)
73 #define PCI_IO_START		(PCI_IO_END - PCI_IO_SIZE)
74 #define FIXADDR_TOP		(PCI_IO_START - SZ_2M)
75 
76 #define KERNEL_START      _text
77 #define KERNEL_END        _end
78 
79 /*
80  * KASAN requires 1/8th of the kernel virtual address space for the shadow
81  * region. KASAN can bloat the stack significantly, so double the (minimum)
82  * stack size when KASAN is in use.
83  */
84 #ifdef CONFIG_KASAN
85 #define KASAN_SHADOW_SCALE_SHIFT 3
86 #define KASAN_SHADOW_SIZE	(UL(1) << (VA_BITS - KASAN_SHADOW_SCALE_SHIFT))
87 #define KASAN_THREAD_SHIFT	1
88 #else
89 #define KASAN_SHADOW_SIZE	(0)
90 #define KASAN_THREAD_SHIFT	0
91 #endif
92 
93 #define MIN_THREAD_SHIFT	(14 + KASAN_THREAD_SHIFT)
94 
95 /*
96  * VMAP'd stacks are allocated at page granularity, so we must ensure that such
97  * stacks are a multiple of page size.
98  */
99 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
100 #define THREAD_SHIFT		PAGE_SHIFT
101 #else
102 #define THREAD_SHIFT		MIN_THREAD_SHIFT
103 #endif
104 
105 #if THREAD_SHIFT >= PAGE_SHIFT
106 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
107 #endif
108 
109 #define THREAD_SIZE		(UL(1) << THREAD_SHIFT)
110 
111 /*
112  * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
113  * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
114  * assembly.
115  */
116 #ifdef CONFIG_VMAP_STACK
117 #define THREAD_ALIGN		(2 * THREAD_SIZE)
118 #else
119 #define THREAD_ALIGN		THREAD_SIZE
120 #endif
121 
122 #define IRQ_STACK_SIZE		THREAD_SIZE
123 
124 #define OVERFLOW_STACK_SIZE	SZ_4K
125 
126 /*
127  * Alignment of kernel segments (e.g. .text, .data).
128  */
129 #if defined(CONFIG_DEBUG_ALIGN_RODATA)
130 /*
131  *  4 KB granule:   1 level 2 entry
132  * 16 KB granule: 128 level 3 entries, with contiguous bit
133  * 64 KB granule:  32 level 3 entries, with contiguous bit
134  */
135 #define SEGMENT_ALIGN			SZ_2M
136 #else
137 /*
138  *  4 KB granule:  16 level 3 entries, with contiguous bit
139  * 16 KB granule:   4 level 3 entries, without contiguous bit
140  * 64 KB granule:   1 level 3 entry
141  */
142 #define SEGMENT_ALIGN			SZ_64K
143 #endif
144 
145 /*
146  * Memory types available.
147  */
148 #define MT_DEVICE_nGnRnE	0
149 #define MT_DEVICE_nGnRE		1
150 #define MT_DEVICE_GRE		2
151 #define MT_NORMAL_NC		3
152 #define MT_NORMAL		4
153 #define MT_NORMAL_WT		5
154 
155 /*
156  * Memory types for Stage-2 translation
157  */
158 #define MT_S2_NORMAL		0xf
159 #define MT_S2_DEVICE_nGnRE	0x1
160 
161 /*
162  * Memory types for Stage-2 translation when ID_AA64MMFR2_EL1.FWB is 0001
163  * Stage-2 enforces Normal-WB and Device-nGnRE
164  */
165 #define MT_S2_FWB_NORMAL	6
166 #define MT_S2_FWB_DEVICE_nGnRE	1
167 
168 #ifdef CONFIG_ARM64_4K_PAGES
169 #define IOREMAP_MAX_ORDER	(PUD_SHIFT)
170 #else
171 #define IOREMAP_MAX_ORDER	(PMD_SHIFT)
172 #endif
173 
174 #ifdef CONFIG_BLK_DEV_INITRD
175 #define __early_init_dt_declare_initrd(__start, __end)			\
176 	do {								\
177 		initrd_start = (__start);				\
178 		initrd_end = (__end);					\
179 	} while (0)
180 #endif
181 
182 #ifndef __ASSEMBLY__
183 
184 #include <linux/bitops.h>
185 #include <linux/mmdebug.h>
186 
187 extern s64			memstart_addr;
188 /* PHYS_OFFSET - the physical address of the start of memory. */
189 #define PHYS_OFFSET		({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
190 
191 /* the virtual base of the kernel image (minus TEXT_OFFSET) */
192 extern u64			kimage_vaddr;
193 
194 /* the offset between the kernel virtual and physical mappings */
195 extern u64			kimage_voffset;
196 
197 static inline unsigned long kaslr_offset(void)
198 {
199 	return kimage_vaddr - KIMAGE_VADDR;
200 }
201 
202 /*
203  * Allow all memory at the discovery stage. We will clip it later.
204  */
205 #define MIN_MEMBLOCK_ADDR	0
206 #define MAX_MEMBLOCK_ADDR	U64_MAX
207 
208 /*
209  * PFNs are used to describe any physical page; this means
210  * PFN 0 == physical address 0.
211  *
212  * This is the PFN of the first RAM page in the kernel
213  * direct-mapped view.  We assume this is the first page
214  * of RAM in the mem_map as well.
215  */
216 #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
217 
218 /*
219  * Physical vs virtual RAM address space conversion.  These are
220  * private definitions which should NOT be used outside memory.h
221  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
222  */
223 
224 
225 /*
226  * The linear kernel range starts in the middle of the virtual adddress
227  * space. Testing the top bit for the start of the region is a
228  * sufficient check.
229  */
230 #define __is_lm_address(addr)	(!!((addr) & BIT(VA_BITS - 1)))
231 
232 #define __lm_to_phys(addr)	(((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
233 #define __kimg_to_phys(addr)	((addr) - kimage_voffset)
234 
235 #define __virt_to_phys_nodebug(x) ({					\
236 	phys_addr_t __x = (phys_addr_t)(x);				\
237 	__is_lm_address(__x) ? __lm_to_phys(__x) :			\
238 			       __kimg_to_phys(__x);			\
239 })
240 
241 #define __pa_symbol_nodebug(x)	__kimg_to_phys((phys_addr_t)(x))
242 
243 #ifdef CONFIG_DEBUG_VIRTUAL
244 extern phys_addr_t __virt_to_phys(unsigned long x);
245 extern phys_addr_t __phys_addr_symbol(unsigned long x);
246 #else
247 #define __virt_to_phys(x)	__virt_to_phys_nodebug(x)
248 #define __phys_addr_symbol(x)	__pa_symbol_nodebug(x)
249 #endif
250 
251 #define __phys_to_virt(x)	((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
252 #define __phys_to_kimg(x)	((unsigned long)((x) + kimage_voffset))
253 
254 /*
255  * Convert a page to/from a physical address
256  */
257 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
258 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
259 
260 /*
261  * Note: Drivers should NOT use these.  They are the wrong
262  * translation for translating DMA addresses.  Use the driver
263  * DMA support - see dma-mapping.h.
264  */
265 #define virt_to_phys virt_to_phys
266 static inline phys_addr_t virt_to_phys(const volatile void *x)
267 {
268 	return __virt_to_phys((unsigned long)(x));
269 }
270 
271 #define phys_to_virt phys_to_virt
272 static inline void *phys_to_virt(phys_addr_t x)
273 {
274 	return (void *)(__phys_to_virt(x));
275 }
276 
277 /*
278  * Drivers should NOT use these either.
279  */
280 #define __pa(x)			__virt_to_phys((unsigned long)(x))
281 #define __pa_symbol(x)		__phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
282 #define __pa_nodebug(x)		__virt_to_phys_nodebug((unsigned long)(x))
283 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
284 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
285 #define virt_to_pfn(x)      __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
286 #define sym_to_pfn(x)	    __phys_to_pfn(__pa_symbol(x))
287 
288 /*
289  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
290  *  virt_addr_valid(k)	indicates whether a virtual address is valid
291  */
292 #define ARCH_PFN_OFFSET		((unsigned long)PHYS_PFN_OFFSET)
293 
294 #ifndef CONFIG_SPARSEMEM_VMEMMAP
295 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
296 #define _virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
297 #else
298 #define __virt_to_pgoff(kaddr)	(((u64)(kaddr) & ~PAGE_OFFSET) / PAGE_SIZE * sizeof(struct page))
299 #define __page_to_voff(kaddr)	(((u64)(kaddr) & ~VMEMMAP_START) * PAGE_SIZE / sizeof(struct page))
300 
301 #define page_to_virt(page)	((void *)((__page_to_voff(page)) | PAGE_OFFSET))
302 #define virt_to_page(vaddr)	((struct page *)((__virt_to_pgoff(vaddr)) | VMEMMAP_START))
303 
304 #define _virt_addr_valid(kaddr)	pfn_valid((((u64)(kaddr) & ~PAGE_OFFSET) \
305 					   + PHYS_OFFSET) >> PAGE_SHIFT)
306 #endif
307 #endif
308 
309 #define _virt_addr_is_linear(kaddr)	(((u64)(kaddr)) >= PAGE_OFFSET)
310 #define virt_addr_valid(kaddr)		(_virt_addr_is_linear(kaddr) && \
311 					 _virt_addr_valid(kaddr))
312 
313 #include <asm-generic/memory_model.h>
314 
315 #endif
316