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Diffstat (limited to 'arch/riscv/include/asm/processor.h')
-rw-r--r-- | arch/riscv/include/asm/processor.h | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h new file mode 100644 index 000000000..fdcc34b4f --- /dev/null +++ b/arch/riscv/include/asm/processor.h @@ -0,0 +1,99 @@ +/* + * Copyright (C) 2012 Regents of the University of California + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#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__ + +#include <asm/barrier.h> + +struct task_struct; +struct pt_regs; + +/* + * Default implementation of macro that returns current + * instruction pointer ("program counter"). + */ +#define current_text_addr() ({ __label__ _l; _l: &&_l; }) + +/* 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; +extern int riscv_of_processor_hart(struct device_node *node); + +extern void riscv_fill_hwcap(void); + +#endif /* __ASSEMBLY__ */ + +#endif /* _ASM_RISCV_PROCESSOR_H */ |