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 */ 23 struct 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 */ 34 struct 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 */ 48 struct 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 84 extern void start_thread(struct pt_regs * regs, unsigned long pc, 85 unsigned long usp); 86 87 extern 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