LXR linux/arch/riscv/include/asm/processor.h

   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#define STACK_TOP_MAX           STACK_TOP
  23#define STACK_ALIGN             16
  24
  25#ifndef __ASSEMBLY__
  26
  27struct task_struct;
  28struct pt_regs;
  29
  30/* CPU-specific state of a task */
  31struct thread_struct {
  32        /* Callee-saved registers */
  33        unsigned long ra;
  34        unsigned long sp;       /* Kernel mode stack */
  35        unsigned long s[12];    /* s[0]: frame pointer */
  36        struct __riscv_d_ext_state fstate;
  37        unsigned long bad_cause;
  38};
  39
  40/* Whitelist the fstate from the task_struct for hardened usercopy */
  41static inline void arch_thread_struct_whitelist(unsigned long *offset,
  42                                                unsigned long *size)
  43{
  44        *offset = offsetof(struct thread_struct, fstate);
  45        *size = sizeof_field(struct thread_struct, fstate);
  46}
  47
  48#define INIT_THREAD {                                   \
  49        .sp = sizeof(init_stack) + (long)&init_stack,   \
  50}
  51
  52#define task_pt_regs(tsk)                                               \
  53        ((struct pt_regs *)(task_stack_page(tsk) + THREAD_SIZE          \
  54                            - ALIGN(sizeof(struct pt_regs), STACK_ALIGN)))
  55
  56#define KSTK_EIP(tsk)           (task_pt_regs(tsk)->epc)
  57#define KSTK_ESP(tsk)           (task_pt_regs(tsk)->sp)
  58
  59
  60/* Do necessary setup to start up a newly executed thread. */
  61extern void start_thread(struct pt_regs *regs,
  62                        unsigned long pc, unsigned long sp);
  63
  64/* Free all resources held by a thread. */
  65static inline void release_thread(struct task_struct *dead_task)
  66{
  67}
  68
  69extern unsigned long get_wchan(struct task_struct *p);
  70
  71
  72static inline void wait_for_interrupt(void)
  73{
  74        __asm__ __volatile__ ("wfi");
  75}
  76
  77struct device_node;
  78int riscv_of_processor_hartid(struct device_node *node);
  79int riscv_of_parent_hartid(struct device_node *node);
  80
  81extern void riscv_fill_hwcap(void);
  82extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
  83
  84#endif /* __ASSEMBLY__ */
  85
  86#endif /* _ASM_RISCV_PROCESSOR_H */
  87