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 27 struct task_struct; 28 struct pt_regs; 29 30 /* CPU-specific state of a task */ 31 struct 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 */ 41 static 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. */ 61 extern void start_thread(struct pt_regs *regs, 62 unsigned long pc, unsigned long sp); 63 64 /* Free all resources held by a thread. */ 65 static inline void release_thread(struct task_struct *dead_task) 66 { 67 } 68 69 extern unsigned long get_wchan(struct task_struct *p); 70 71 72 static inline void wait_for_interrupt(void) 73 { 74 __asm__ __volatile__ ("wfi"); 75 } 76 77 struct device_node; 78 int riscv_of_processor_hartid(struct device_node *node); 79 int riscv_of_parent_hartid(struct device_node *node); 80 81 extern void riscv_fill_hwcap(void); 82 extern 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