/* SPDX-License-Identifier: GPL-2.0-only */ /* * Copyright (C) 2012 Regents of the University of California */ #ifndef _ASM_RISCV_PROCESSOR_H #define _ASM_RISCV_PROCESSOR_H #include <linux/const.h> #include <asm/ptrace.h> /* * This decides where the kernel will search for a free chunk of vm * space during mmap's. */ #define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3) #define STACK_TOP TASK_SIZE #define STACK_TOP_MAX STACK_TOP #define STACK_ALIGN 16 #ifndef __ASSEMBLY__ struct task_struct; struct pt_regs; /* CPU-specific state of a task */ struct thread_struct { /* Callee-saved registers */ unsigned long ra; unsigned long sp; /* Kernel mode stack */ unsigned long s[12]; /* s[0]: frame pointer */ struct __riscv_d_ext_state fstate; }; #define INIT_THREAD { \ .sp = sizeof(init_stack) + (long)&init_stack, \ } #define task_pt_regs(tsk) \ ((struct pt_regs *)(task_stack_page(tsk) + THREAD_SIZE \ - ALIGN(sizeof(struct pt_regs), STACK_ALIGN))) #define KSTK_EIP(tsk) (task_pt_regs(tsk)->sepc) #define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp) /* Do necessary setup to start up a newly executed thread. */ extern void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp); /* Free all resources held by a thread. */ static inline void release_thread(struct task_struct *dead_task) { } extern unsigned long get_wchan(struct task_struct *p); static inline void cpu_relax(void) { #ifdef __riscv_muldiv int dummy; /* In lieu of a halt instruction, induce a long-latency stall. */ __asm__ __volatile__ ("div %0, %0, zero" : "=r" (dummy)); #endif barrier(); } static inline void wait_for_interrupt(void) { __asm__ __volatile__ ("wfi"); } struct device_node; int riscv_of_processor_hartid(struct device_node *node); extern void riscv_fill_hwcap(void); #endif /* __ASSEMBLY__ */ #endif /* _ASM_RISCV_PROCESSOR_H */