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 <vdso/processor.h>
12
13 #include <asm/ptrace.h>
14
15 /*
16 * This decides where the kernel will search for a free chunk of vm
17 * space during mmap's.
18 */
19 #define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3)
20
21 #define STACK_TOP TASK_SIZE
22 #ifdef CONFIG_64BIT
23 #define STACK_TOP_MAX TASK_SIZE_64
24 #else
25 #define STACK_TOP_MAX TASK_SIZE
26 #endif
27 #define STACK_ALIGN 16
28
29 #ifndef __ASSEMBLY__
30
31 struct task_struct;
32 struct pt_regs;
33
34 /* CPU-specific state of a task */
35 struct thread_struct {
36 /* Callee-saved registers */
37 unsigned long ra;
38 unsigned long sp; /* Kernel mode stack */
39 unsigned long s[12]; /* s[0]: frame pointer */
40 struct __riscv_d_ext_state fstate;
41 unsigned long bad_cause;
42 };
43
44 /* Whitelist the fstate from the task_struct for hardened usercopy */
arch_thread_struct_whitelist(unsigned long * offset,unsigned long * size)45 static inline void arch_thread_struct_whitelist(unsigned long *offset,
46 unsigned long *size)
47 {
48 *offset = offsetof(struct thread_struct, fstate);
49 *size = sizeof_field(struct thread_struct, fstate);
50 }
51
52 #define INIT_THREAD { \
53 .sp = sizeof(init_stack) + (long)&init_stack, \
54 }
55
56 #define task_pt_regs(tsk) \
57 ((struct pt_regs *)(task_stack_page(tsk) + THREAD_SIZE \
58 - ALIGN(sizeof(struct pt_regs), STACK_ALIGN)))
59
60 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->epc)
61 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp)
62
63
64 /* Do necessary setup to start up a newly executed thread. */
65 extern void start_thread(struct pt_regs *regs,
66 unsigned long pc, unsigned long sp);
67
68 extern unsigned long __get_wchan(struct task_struct *p);
69
70
wait_for_interrupt(void)71 static inline void wait_for_interrupt(void)
72 {
73 __asm__ __volatile__ ("wfi");
74 }
75
76 struct device_node;
77 int riscv_of_processor_hartid(struct device_node *node, unsigned long *hartid);
78 int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid);
79
80 extern void riscv_fill_hwcap(void);
81 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
82
83 #endif /* __ASSEMBLY__ */
84
85 #endif /* _ASM_RISCV_PROCESSOR_H */
86