1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Memory layout definitions for the Hexagon architecture
4 *
5 * Copyright (c) 2010-2013, The Linux Foundation. All rights reserved.
6 */
7
8#ifndef _ASM_HEXAGON_MEM_LAYOUT_H
9#define _ASM_HEXAGON_MEM_LAYOUT_H
10
11#include <linux/const.h>
12
13/*
14 * Have to do this for ginormous numbers, else they get printed as
15 * negative numbers, which the linker no likey when you try to
16 * assign it to the location counter.
17 */
18
19#define PAGE_OFFSET			_AC(0xc0000000, UL)
20
21/*
22 * Compiling for a platform that needs a crazy physical offset
23 * (like if the memory starts at 1GB and up) means we need
24 * an actual PHYS_OFFSET.  Should be set up in head.S.
25 */
26
27#ifdef CONFIG_HEXAGON_PHYS_OFFSET
28#ifndef __ASSEMBLY__
29extern unsigned long	__phys_offset;
30#endif
31#define PHYS_OFFSET	__phys_offset
32#endif
33
34#ifndef PHYS_OFFSET
35#define PHYS_OFFSET	0
36#endif
37
38#define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
39#define ARCH_PFN_OFFSET	PHYS_PFN_OFFSET
40
41#define TASK_SIZE			(PAGE_OFFSET)
42
43/*  not sure how these are used yet  */
44#define STACK_TOP			TASK_SIZE
45#define STACK_TOP_MAX			TASK_SIZE
46
47#ifndef __ASSEMBLY__
48enum fixed_addresses {
49	FIX_KMAP_BEGIN,
50	FIX_KMAP_END,  /*  check for per-cpuism  */
51	__end_of_fixed_addresses
52};
53
54#define MIN_KERNEL_SEG (PAGE_OFFSET >> PGDIR_SHIFT)   /* L1 shift is 22 bits */
55extern int max_kernel_seg;
56
57/*
58 * Start of vmalloc virtual address space for kernel;
59 * supposed to be based on the amount of physical memory available
60 */
61
62#define VMALLOC_START ((unsigned long) __va(high_memory + VMALLOC_OFFSET))
63
64/* Gap between physical ram and vmalloc space for guard purposes. */
65#define VMALLOC_OFFSET PAGE_SIZE
66
67/*
68 * Create the space between VMALLOC_START and FIXADDR_TOP backwards
69 * from the ... "top".
70 *
71 * Permanent IO mappings will live at 0xfexx_xxxx
72 * Hypervisor occupies the last 16MB page at 0xffxxxxxx
73 */
74
75#define FIXADDR_TOP     0xfe000000
76#define FIXADDR_SIZE    (__end_of_fixed_addresses << PAGE_SHIFT)
77#define FIXADDR_START   (FIXADDR_TOP - FIXADDR_SIZE)
78
79/*
80 * "permanent kernel mappings", defined as long-lasting mappings of
81 * high-memory page frames into the kernel address space.
82 */
83
84#define LAST_PKMAP	PTRS_PER_PTE
85#define LAST_PKMAP_MASK	(LAST_PKMAP - 1)
86#define PKMAP_NR(virt)	((virt - PKMAP_BASE) >> PAGE_SHIFT)
87#define PKMAP_ADDR(nr)	(PKMAP_BASE + ((nr) << PAGE_SHIFT))
88
89/*
90 * To the "left" of the fixed map space is the kmap space
91 *
92 * "Permanent Kernel Mappings"; fancy (or less fancy) PTE table
93 * that looks like it's actually walked.
94 * Need to check the alignment/shift usage; some archs use
95 * PMD_MASK on this value
96 */
97#define PKMAP_BASE (FIXADDR_START-PAGE_SIZE*LAST_PKMAP)
98
99/*
100 * 2 pages of guard gap between where vmalloc area ends
101 * and pkmap_base begins.
102 */
103#define VMALLOC_END (PKMAP_BASE-PAGE_SIZE*2)
104#endif /*  !__ASSEMBLY__  */
105
106
107#endif /* _ASM_HEXAGON_MEM_LAYOUT_H */
108