Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/*
2 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * vineetg: March 2009
9 * -Implemented task_pt_regs( )
10 *
11 * Amit Bhor, Sameer Dhavale, Ashwin Chaugule: Codito Technologies 2004
12 */
13
14#ifndef __ASM_ARC_PROCESSOR_H
15#define __ASM_ARC_PROCESSOR_H
16
17#ifndef __ASSEMBLY__
18
19#include <asm/ptrace.h>
20
21#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
22/* These DPFP regs need to be saved/restored across ctx-sw */
23struct arc_fpu {
24 struct {
25 unsigned int l, h;
26 } aux_dpfp[2];
27};
28#endif
29
30/* Arch specific stuff which needs to be saved per task.
31 * However these items are not so important so as to earn a place in
32 * struct thread_info
33 */
34struct thread_struct {
35 unsigned long ksp; /* kernel mode stack pointer */
36 unsigned long callee_reg; /* pointer to callee regs */
37 unsigned long fault_address; /* dbls as brkpt holder as well */
38#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
39 struct arc_fpu fpu;
40#endif
41};
42
43#define INIT_THREAD { \
44 .ksp = sizeof(init_stack) + (unsigned long) init_stack, \
45}
46
47/* Forward declaration, a strange C thing */
48struct task_struct;
49
50#define task_pt_regs(p) \
51 ((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1)
52
53/* Free all resources held by a thread */
54#define release_thread(thread) do { } while (0)
55
56/*
57 * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise
58 * get optimised away by gcc
59 */
60#ifdef CONFIG_SMP
61#define cpu_relax() __asm__ __volatile__ ("" : : : "memory")
62#else
63#define cpu_relax() do { } while (0)
64#endif
65
66#define cpu_relax_lowlatency() cpu_relax()
67
68#define copy_segments(tsk, mm) do { } while (0)
69#define release_segments(mm) do { } while (0)
70
71#define KSTK_EIP(tsk) (task_pt_regs(tsk)->ret)
72#define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp)
73
74/*
75 * Where abouts of Task's sp, fp, blink when it was last seen in kernel mode.
76 * Look in process.c for details of kernel stack layout
77 */
78#define TSK_K_ESP(tsk) (tsk->thread.ksp)
79
80#define TSK_K_REG(tsk, off) (*((unsigned long *)(TSK_K_ESP(tsk) + \
81 sizeof(struct callee_regs) + off)))
82
83#define TSK_K_BLINK(tsk) TSK_K_REG(tsk, 4)
84#define TSK_K_FP(tsk) TSK_K_REG(tsk, 0)
85
86#define thread_saved_pc(tsk) TSK_K_BLINK(tsk)
87
88extern void start_thread(struct pt_regs * regs, unsigned long pc,
89 unsigned long usp);
90
91extern unsigned int get_wchan(struct task_struct *p);
92
93/*
94 * Default implementation of macro that returns current
95 * instruction pointer ("program counter").
96 * Should the PC register be read instead ? This macro does not seem to
97 * be used in many places so this wont be all that bad.
98 */
99#define current_text_addr() ({ __label__ _l; _l: &&_l; })
100
101#endif /* !__ASSEMBLY__ */
102
103/*
104 * System Memory Map on ARC
105 *
106 * ---------------------------- (lower 2G, Translated) -------------------------
107 * 0x0000_0000 0x5FFF_FFFF (user vaddr: TASK_SIZE)
108 * 0x6000_0000 0x6FFF_FFFF (reserved gutter between U/K)
109 * 0x7000_0000 0x7FFF_FFFF (kvaddr: vmalloc/modules/pkmap..)
110 *
111 * PAGE_OFFSET ---------------- (Upper 2G, Untranslated) -----------------------
112 * 0x8000_0000 0xBFFF_FFFF (kernel direct mapped)
113 * 0xC000_0000 0xFFFF_FFFF (peripheral uncached space)
114 * -----------------------------------------------------------------------------
115 */
116#define VMALLOC_START 0x70000000
117#define VMALLOC_SIZE (PAGE_OFFSET - VMALLOC_START)
118#define VMALLOC_END (VMALLOC_START + VMALLOC_SIZE)
119
120#define USER_KERNEL_GUTTER 0x10000000
121
122#define TASK_SIZE (VMALLOC_START - USER_KERNEL_GUTTER)
123
124#define STACK_TOP TASK_SIZE
125#define STACK_TOP_MAX STACK_TOP
126
127/* This decides where the kernel will search for a free chunk of vm
128 * space during mmap's.
129 */
130#define TASK_UNMAPPED_BASE (TASK_SIZE / 3)
131
132#endif /* __ASM_ARC_PROCESSOR_H */