1/* 2 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * vineetg: March 2009 9 * -Implemented task_pt_regs( ) 10 * 11 * Amit Bhor, Sameer Dhavale, Ashwin Chaugule: Codito Technologies 2004 12 */ 13 14#ifndef __ASM_ARC_PROCESSOR_H 15#define __ASM_ARC_PROCESSOR_H 16 17#ifndef __ASSEMBLY__ 18 19#include <asm/ptrace.h> 20 21#ifdef CONFIG_ARC_FPU_SAVE_RESTORE 22/* These DPFP regs need to be saved/restored across ctx-sw */ 23struct arc_fpu { 24 struct { 25 unsigned int l, h; 26 } aux_dpfp[2]; 27}; 28#endif 29 30/* Arch specific stuff which needs to be saved per task. 31 * However these items are not so important so as to earn a place in 32 * struct thread_info 33 */ 34struct thread_struct { 35 unsigned long ksp; /* kernel mode stack pointer */ 36 unsigned long callee_reg; /* pointer to callee regs */ 37 unsigned long fault_address; /* dbls as brkpt holder as well */ 38#ifdef CONFIG_ARC_FPU_SAVE_RESTORE 39 struct arc_fpu fpu; 40#endif 41}; 42 43#define INIT_THREAD { \ 44 .ksp = sizeof(init_stack) + (unsigned long) init_stack, \ 45} 46 47/* Forward declaration, a strange C thing */ 48struct task_struct; 49 50#define task_pt_regs(p) \ 51 ((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1) 52 53/* Free all resources held by a thread */ 54#define release_thread(thread) do { } while (0) 55 56/* 57 * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise 58 * get optimised away by gcc 59 */ 60#define cpu_relax() __asm__ __volatile__ ("" : : : "memory") 61 62#define cpu_relax_lowlatency() cpu_relax() 63 64#define copy_segments(tsk, mm) do { } while (0) 65#define release_segments(mm) do { } while (0) 66 67#define KSTK_EIP(tsk) (task_pt_regs(tsk)->ret) 68#define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp) 69 70/* 71 * Where abouts of Task's sp, fp, blink when it was last seen in kernel mode. 72 * Look in process.c for details of kernel stack layout 73 */ 74#define TSK_K_ESP(tsk) (tsk->thread.ksp) 75 76#define TSK_K_REG(tsk, off) (*((unsigned long *)(TSK_K_ESP(tsk) + \ 77 sizeof(struct callee_regs) + off))) 78 79#define TSK_K_BLINK(tsk) TSK_K_REG(tsk, 4) 80#define TSK_K_FP(tsk) TSK_K_REG(tsk, 0) 81 82#define thread_saved_pc(tsk) TSK_K_BLINK(tsk) 83 84extern void start_thread(struct pt_regs * regs, unsigned long pc, 85 unsigned long usp); 86 87extern unsigned int get_wchan(struct task_struct *p); 88 89/* 90 * Default implementation of macro that returns current 91 * instruction pointer ("program counter"). 92 * Should the PC register be read instead ? This macro does not seem to 93 * be used in many places so this wont be all that bad. 94 */ 95#define current_text_addr() ({ __label__ _l; _l: &&_l; }) 96 97#endif /* !__ASSEMBLY__ */ 98 99/* 100 * System Memory Map on ARC 101 * 102 * ---------------------------- (lower 2G, Translated) ------------------------- 103 * 0x0000_0000 0x5FFF_FFFF (user vaddr: TASK_SIZE) 104 * 0x6000_0000 0x6FFF_FFFF (reserved gutter between U/K) 105 * 0x7000_0000 0x7FFF_FFFF (kvaddr: vmalloc/modules/pkmap..) 106 * 107 * PAGE_OFFSET ---------------- (Upper 2G, Untranslated) ----------------------- 108 * 0x8000_0000 0xBFFF_FFFF (kernel direct mapped) 109 * 0xC000_0000 0xFFFF_FFFF (peripheral uncached space) 110 * ----------------------------------------------------------------------------- 111 */ 112#define VMALLOC_START 0x70000000 113 114/* 115 * 1 PGDIR_SIZE each for fixmap/pkmap, 2 PGDIR_SIZE gutter 116 * See asm/highmem.h for details 117 */ 118#define VMALLOC_SIZE (PAGE_OFFSET - VMALLOC_START - PGDIR_SIZE * 4) 119#define VMALLOC_END (VMALLOC_START + VMALLOC_SIZE) 120 121#define USER_KERNEL_GUTTER 0x10000000 122 123#define TASK_SIZE (VMALLOC_START - USER_KERNEL_GUTTER) 124 125#define STACK_TOP TASK_SIZE 126#define STACK_TOP_MAX STACK_TOP 127 128/* This decides where the kernel will search for a free chunk of vm 129 * space during mmap's. 130 */ 131#define TASK_UNMAPPED_BASE (TASK_SIZE / 3) 132 133#endif /* __ASM_ARC_PROCESSOR_H */ 134