1/* SPDX-License-Identifier: GPL-2.0 */
 2// Copyright (C) 2005-2017 Andes Technology Corporation
 3
 4#ifndef __ASM_NDS32_MEMORY_H
 5#define __ASM_NDS32_MEMORY_H
 6
 7#include <linux/compiler.h>
 8#include <linux/sizes.h>
 9
10#ifndef __ASSEMBLY__
11#include <asm/page.h>
12#endif
13
14#ifndef PHYS_OFFSET
15#define PHYS_OFFSET     (0x0)
16#endif
17
18/*
19 * TASK_SIZE - the maximum size of a user space task.
20 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
21 */
22#define TASK_SIZE		((CONFIG_PAGE_OFFSET) - (SZ_32M))
23#define TASK_UNMAPPED_BASE	ALIGN(TASK_SIZE / 3, SZ_32M)
24#define PAGE_OFFSET		(CONFIG_PAGE_OFFSET)
25
26/*
27 * Physical vs virtual RAM address space conversion.  These are
28 * private definitions which should NOT be used outside memory.h
29 * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
30 */
31#ifndef __virt_to_phys
32#define __virt_to_phys(x)	((x) - PAGE_OFFSET + PHYS_OFFSET)
33#define __phys_to_virt(x)	((x) - PHYS_OFFSET + PAGE_OFFSET)
34#endif
35
36/*
37 * The module space lives between the addresses given by TASK_SIZE
38 * and PAGE_OFFSET - it must be within 32MB of the kernel text.
39 */
40#define MODULES_END	(PAGE_OFFSET)
41#define MODULES_VADDR	(MODULES_END - SZ_32M)
42
43#if TASK_SIZE > MODULES_VADDR
44#error Top of user space clashes with start of module space
45#endif
46
47#ifndef __ASSEMBLY__
48
49/*
50 * PFNs are used to describe any physical page; this means
51 * PFN 0 == physical address 0.
52 *
53 * This is the PFN of the first RAM page in the kernel
54 * direct-mapped view.  We assume this is the first page
55 * of RAM in the mem_map as well.
56 */
57#define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
58
59/*
60 * Drivers should NOT use these either.
61 */
62#define __pa(x)			__virt_to_phys((unsigned long)(x))
63#define __va(x)			((void *)__phys_to_virt((unsigned long)(x)))
64
65/*
66 * Conversion between a struct page and a physical address.
67 *
68 * Note: when converting an unknown physical address to a
69 * struct page, the resulting pointer must be validated
70 * using VALID_PAGE().  It must return an invalid struct page
71 * for any physical address not corresponding to a system
72 * RAM address.
73 *
74 *  pfn_valid(pfn)	indicates whether a PFN number is valid
75 *
76 *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
77 *  virt_addr_valid(k)	indicates whether a virtual address is valid
78 */
79#ifndef CONFIG_DISCONTIGMEM
80
81#define ARCH_PFN_OFFSET		PHYS_PFN_OFFSET
82#define pfn_valid(pfn)		((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
83
84#define virt_to_page(kaddr)	(pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))
85#define virt_addr_valid(kaddr)	((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
86
87#else /* CONFIG_DISCONTIGMEM */
88#error CONFIG_DISCONTIGMEM is not supported yet.
89#endif /* !CONFIG_DISCONTIGMEM */
90
91#define page_to_phys(page)	(page_to_pfn(page) << PAGE_SHIFT)
92
93#endif
94
95#include <asm-generic/memory_model.h>
96
97#endif