1 /* 2 * OpenRISC Linux 3 * 4 * Linux architectural port borrowing liberally from similar works of 5 * others. All original copyrights apply as per the original source 6 * declaration. 7 * 8 * OpenRISC implementation: 9 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com> 10 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se> 11 * et al. 12 * 13 * This program is free software; you can redistribute it and/or modify 14 * it under the terms of the GNU General Public License as published by 15 * the Free Software Foundation; either version 2 of the License, or 16 * (at your option) any later version. 17 */ 18 19 #ifndef __ASM_OPENRISC_PROCESSOR_H 20 #define __ASM_OPENRISC_PROCESSOR_H 21 22 #include <asm/spr_defs.h> 23 #include <asm/page.h> 24 #include <asm/ptrace.h> 25 26 #define STACK_TOP TASK_SIZE 27 #define STACK_TOP_MAX STACK_TOP 28 /* Kernel and user SR register setting */ 29 #define KERNEL_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_ICE \ 30 | SPR_SR_DCE | SPR_SR_SM) 31 #define USER_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_ICE \ 32 | SPR_SR_DCE | SPR_SR_IEE | SPR_SR_TEE) 33 /* 34 * Default implementation of macro that returns current 35 * instruction pointer ("program counter"). 36 */ 37 #define current_text_addr() ({ __label__ _l; _l: &&_l; }) 38 39 /* 40 * User space process size. This is hardcoded into a few places, 41 * so don't change it unless you know what you are doing. 42 */ 43 44 #define TASK_SIZE (0x80000000UL) 45 46 /* This decides where the kernel will search for a free chunk of vm 47 * space during mmap's. 48 */ 49 #define TASK_UNMAPPED_BASE (TASK_SIZE / 8 * 3) 50 51 #ifndef __ASSEMBLY__ 52 53 struct task_struct; 54 55 struct thread_struct { 56 }; 57 58 /* 59 * At user->kernel entry, the pt_regs struct is stacked on the top of the 60 * kernel-stack. This macro allows us to find those regs for a task. 61 * Notice that subsequent pt_regs stackings, like recursive interrupts 62 * occurring while we're in the kernel, won't affect this - only the first 63 * user->kernel transition registers are reached by this (i.e. not regs 64 * for running signal handler) 65 */ 66 #define user_regs(thread_info) (((struct pt_regs *)((unsigned long)(thread_info) + THREAD_SIZE - STACK_FRAME_OVERHEAD)) - 1) 67 68 /* 69 * Dito but for the currently running task 70 */ 71 72 #define task_pt_regs(task) user_regs(task_thread_info(task)) 73 74 #define INIT_SP (sizeof(init_stack) + (unsigned long) &init_stack) 75 76 #define INIT_THREAD { } 77 78 79 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc) 80 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp) 81 82 83 void start_thread(struct pt_regs *regs, unsigned long nip, unsigned long sp); 84 void release_thread(struct task_struct *); 85 unsigned long get_wchan(struct task_struct *p); 86 87 /* 88 * Free current thread data structures etc.. 89 */ 90 91 extern inline void exit_thread(void) 92 { 93 /* Nothing needs to be done. */ 94 } 95 96 /* 97 * Return saved PC of a blocked thread. For now, this is the "user" PC 98 */ 99 extern unsigned long thread_saved_pc(struct task_struct *t); 100 101 #define init_stack (init_thread_union.stack) 102 103 #define cpu_relax() barrier() 104 #define cpu_relax_lowlatency() cpu_relax() 105 106 #endif /* __ASSEMBLY__ */ 107 #endif /* __ASM_OPENRISC_PROCESSOR_H */ 108