1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4 *
5 * vineetg: March 2009
6 *  -Implemented task_pt_regs( )
7 *
8 * Amit Bhor, Sameer Dhavale, Ashwin Chaugule: Codito Technologies 2004
9 */
10
11#ifndef __ASM_ARC_PROCESSOR_H
12#define __ASM_ARC_PROCESSOR_H
13
14#ifndef __ASSEMBLY__
15
16#include <asm/ptrace.h>
17#include <asm/dsp.h>
18#include <asm/fpu.h>
19
20/* Arch specific stuff which needs to be saved per task.
21 * However these items are not so important so as to earn a place in
22 * struct thread_info
23 */
24struct thread_struct {
25	unsigned long callee_reg;	/* pointer to callee regs */
26	unsigned long fault_address;	/* dbls as brkpt holder as well */
27#ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS
28	struct dsp_callee_regs dsp;
29#endif
30#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
31	struct arc_fpu fpu;
32#endif
33};
34
35#define INIT_THREAD  { }
36
37/* Forward declaration, a strange C thing */
38struct task_struct;
39
40#define task_pt_regs(p) \
41	((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1)
42
43/*
44 * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise
45 * get optimised away by gcc
46 */
47#define cpu_relax()		barrier()
48
49#define KSTK_EIP(tsk)   (task_pt_regs(tsk)->ret)
50#define KSTK_ESP(tsk)   (task_pt_regs(tsk)->sp)
51
52/*
53 * Where about of Task's sp, fp, blink when it was last seen in kernel mode.
54 * Look in process.c for details of kernel stack layout
55 */
56#define TSK_K_ESP(tsk)		(task_thread_info(tsk)->ksp)
57
58#define TSK_K_REG(tsk, off)	(*((unsigned long *)(TSK_K_ESP(tsk) + \
59					sizeof(struct callee_regs) + off)))
60
61#define TSK_K_BLINK(tsk)	TSK_K_REG(tsk, 4)
62#define TSK_K_FP(tsk)		TSK_K_REG(tsk, 0)
63
64extern void start_thread(struct pt_regs * regs, unsigned long pc,
65			 unsigned long usp);
66
67extern unsigned int __get_wchan(struct task_struct *p);
68
69#endif /* !__ASSEMBLY__ */
70
71/*
72 * Default System Memory Map on ARC
73 *
74 * ---------------------------- (lower 2G, Translated) -------------------------
75 * 0x0000_0000		0x5FFF_FFFF	(user vaddr: TASK_SIZE)
76 * 0x6000_0000		0x6FFF_FFFF	(reserved gutter between U/K)
77 * 0x7000_0000		0x7FFF_FFFF	(kvaddr: vmalloc/modules/pkmap..)
78 *
79 * PAGE_OFFSET ---------------- (Upper 2G, Untranslated) -----------------------
80 * 0x8000_0000		0xBFFF_FFFF	(kernel direct mapped)
81 * 0xC000_0000		0xFFFF_FFFF	(peripheral uncached space)
82 * -----------------------------------------------------------------------------
83 */
84
85#define TASK_SIZE	0x60000000
86
87#define VMALLOC_START	(PAGE_OFFSET - (CONFIG_ARC_KVADDR_SIZE << 20))
88
89/* 1 PGDIR_SIZE each for fixmap/pkmap, 2 PGDIR_SIZE gutter (see asm/highmem.h) */
90#define VMALLOC_SIZE	((CONFIG_ARC_KVADDR_SIZE << 20) - PMD_SIZE * 4)
91
92#define VMALLOC_END	(VMALLOC_START + VMALLOC_SIZE)
93
94#define USER_KERNEL_GUTTER    (VMALLOC_START - TASK_SIZE)
95
96#define STACK_TOP       TASK_SIZE
97#define STACK_TOP_MAX   STACK_TOP
98
99/* This decides where the kernel will search for a free chunk of vm
100 * space during mmap's.
101 */
102#define TASK_UNMAPPED_BASE      (TASK_SIZE / 3)
103
104#endif /* __ASM_ARC_PROCESSOR_H */
105