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