Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2012 Regents of the University of California
4 */
5
6#ifndef _ASM_RISCV_PROCESSOR_H
7#define _ASM_RISCV_PROCESSOR_H
8
9#include <linux/const.h>
10
11#include <asm/ptrace.h>
12
13/*
14 * This decides where the kernel will search for a free chunk of vm
15 * space during mmap's.
16 */
17#define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3)
18
19#define STACK_TOP TASK_SIZE
20#define STACK_TOP_MAX STACK_TOP
21#define STACK_ALIGN 16
22
23#ifndef __ASSEMBLY__
24
25struct task_struct;
26struct pt_regs;
27
28/* CPU-specific state of a task */
29struct thread_struct {
30 /* Callee-saved registers */
31 unsigned long ra;
32 unsigned long sp; /* Kernel mode stack */
33 unsigned long s[12]; /* s[0]: frame pointer */
34 struct __riscv_d_ext_state fstate;
35};
36
37#define INIT_THREAD { \
38 .sp = sizeof(init_stack) + (long)&init_stack, \
39}
40
41#define task_pt_regs(tsk) \
42 ((struct pt_regs *)(task_stack_page(tsk) + THREAD_SIZE \
43 - ALIGN(sizeof(struct pt_regs), STACK_ALIGN)))
44
45#define KSTK_EIP(tsk) (task_pt_regs(tsk)->sepc)
46#define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp)
47
48
49/* Do necessary setup to start up a newly executed thread. */
50extern void start_thread(struct pt_regs *regs,
51 unsigned long pc, unsigned long sp);
52
53/* Free all resources held by a thread. */
54static inline void release_thread(struct task_struct *dead_task)
55{
56}
57
58extern unsigned long get_wchan(struct task_struct *p);
59
60
61static inline void cpu_relax(void)
62{
63#ifdef __riscv_muldiv
64 int dummy;
65 /* In lieu of a halt instruction, induce a long-latency stall. */
66 __asm__ __volatile__ ("div %0, %0, zero" : "=r" (dummy));
67#endif
68 barrier();
69}
70
71static inline void wait_for_interrupt(void)
72{
73 __asm__ __volatile__ ("wfi");
74}
75
76struct device_node;
77int riscv_of_processor_hartid(struct device_node *node);
78
79extern void riscv_fill_hwcap(void);
80
81#endif /* __ASSEMBLY__ */
82
83#endif /* _ASM_RISCV_PROCESSOR_H */