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#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
  31struct task_struct;
  32struct pt_regs;
  33
  34/* CPU-specific state of a task */
  35struct 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 */
  45static 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. */
  65extern void start_thread(struct pt_regs *regs,
  66                        unsigned long pc, unsigned long sp);
  67
  68/* Free all resources held by a thread. */
  69static inline void release_thread(struct task_struct *dead_task)
  70{
  71}
  72
  73extern unsigned long __get_wchan(struct task_struct *p);
  74
  75
  76static inline void wait_for_interrupt(void)
  77{
  78        __asm__ __volatile__ ("wfi");
  79}
  80
  81struct device_node;
  82int riscv_of_processor_hartid(struct device_node *node);
  83int riscv_of_parent_hartid(struct device_node *node);
  84
  85extern void riscv_fill_hwcap(void);
  86extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
  87
  88#endif /* __ASSEMBLY__ */
  89
  90#endif /* _ASM_RISCV_PROCESSOR_H */
  91