Vineet Gupta | 3be80aa | 2013-01-18 15:12:17 +0530 | [diff] [blame] | 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 | #ifdef __KERNEL__ |
| 18 | |
| 19 | #ifndef __ASSEMBLY__ |
| 20 | |
| 21 | #include <asm/arcregs.h> /* for STATUS_E1_MASK et all */ |
Vineet Gupta | 16f9afe | 2013-05-27 21:43:41 +0530 | [diff] [blame] | 22 | #include <asm/ptrace.h> |
Vineet Gupta | 3be80aa | 2013-01-18 15:12:17 +0530 | [diff] [blame] | 23 | |
| 24 | /* Arch specific stuff which needs to be saved per task. |
| 25 | * However these items are not so important so as to earn a place in |
| 26 | * struct thread_info |
| 27 | */ |
| 28 | struct thread_struct { |
| 29 | unsigned long ksp; /* kernel mode stack pointer */ |
| 30 | unsigned long callee_reg; /* pointer to callee regs */ |
| 31 | unsigned long fault_address; /* dbls as brkpt holder as well */ |
Vineet Gupta | bf90e1e | 2013-01-18 15:12:18 +0530 | [diff] [blame] | 32 | #ifdef CONFIG_ARC_FPU_SAVE_RESTORE |
| 33 | struct arc_fpu fpu; |
| 34 | #endif |
Vineet Gupta | 3be80aa | 2013-01-18 15:12:17 +0530 | [diff] [blame] | 35 | }; |
| 36 | |
| 37 | #define INIT_THREAD { \ |
| 38 | .ksp = sizeof(init_stack) + (unsigned long) init_stack, \ |
| 39 | } |
| 40 | |
| 41 | /* Forward declaration, a strange C thing */ |
| 42 | struct task_struct; |
| 43 | |
| 44 | /* |
| 45 | * Return saved PC of a blocked thread. |
| 46 | */ |
| 47 | unsigned long thread_saved_pc(struct task_struct *t); |
| 48 | |
| 49 | #define task_pt_regs(p) \ |
Vineet Gupta | 283237a | 2013-05-28 09:34:45 +0530 | [diff] [blame] | 50 | ((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1) |
Vineet Gupta | 3be80aa | 2013-01-18 15:12:17 +0530 | [diff] [blame] | 51 | |
| 52 | /* Free all resources held by a thread. */ |
| 53 | #define release_thread(thread) do { } while (0) |
| 54 | |
| 55 | /* Prepare to copy thread state - unlazy all lazy status */ |
| 56 | #define prepare_to_copy(tsk) do { } while (0) |
| 57 | |
Vineet Gupta | 41195d2 | 2013-01-18 15:12:23 +0530 | [diff] [blame] | 58 | /* |
| 59 | * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise |
| 60 | * get optimised away by gcc |
| 61 | */ |
| 62 | #ifdef CONFIG_SMP |
| 63 | #define cpu_relax() __asm__ __volatile__ ("" : : : "memory") |
| 64 | #else |
Vineet Gupta | 3be80aa | 2013-01-18 15:12:17 +0530 | [diff] [blame] | 65 | #define cpu_relax() do { } while (0) |
Vineet Gupta | 41195d2 | 2013-01-18 15:12:23 +0530 | [diff] [blame] | 66 | #endif |
Vineet Gupta | 3be80aa | 2013-01-18 15:12:17 +0530 | [diff] [blame] | 67 | |
Vineet Gupta | 3be80aa | 2013-01-18 15:12:17 +0530 | [diff] [blame] | 68 | #define copy_segments(tsk, mm) do { } while (0) |
| 69 | #define release_segments(mm) do { } while (0) |
| 70 | |
| 71 | #define KSTK_EIP(tsk) (task_pt_regs(tsk)->ret) |
| 72 | |
| 73 | /* |
| 74 | * Where abouts of Task's sp, fp, blink when it was last seen in kernel mode. |
Vineet Gupta | 16f9afe | 2013-05-27 21:43:41 +0530 | [diff] [blame] | 75 | * Look in process.c for details of kernel stack layout |
Vineet Gupta | 3be80aa | 2013-01-18 15:12:17 +0530 | [diff] [blame] | 76 | */ |
| 77 | #define KSTK_ESP(tsk) (tsk->thread.ksp) |
Vineet Gupta | 16f9afe | 2013-05-27 21:43:41 +0530 | [diff] [blame] | 78 | |
| 79 | #define KSTK_REG(tsk, off) (*((unsigned int *)(KSTK_ESP(tsk) + \ |
| 80 | sizeof(struct callee_regs) + off))) |
| 81 | |
| 82 | #define KSTK_BLINK(tsk) KSTK_REG(tsk, 4) |
| 83 | #define KSTK_FP(tsk) KSTK_REG(tsk, 0) |
Vineet Gupta | 3be80aa | 2013-01-18 15:12:17 +0530 | [diff] [blame] | 84 | |
| 85 | /* |
| 86 | * Do necessary setup to start up a newly executed thread. |
| 87 | * |
| 88 | * E1,E2 so that Interrupts are enabled in user mode |
| 89 | * L set, so Loop inhibited to begin with |
| 90 | * lp_start and lp_end seeded with bogus non-zero values so to easily catch |
| 91 | * the ARC700 sr to lp_start hardware bug |
| 92 | */ |
| 93 | #define start_thread(_regs, _pc, _usp) \ |
| 94 | do { \ |
| 95 | set_fs(USER_DS); /* reads from user space */ \ |
| 96 | (_regs)->ret = (_pc); \ |
| 97 | /* Interrupts enabled in User Mode */ \ |
| 98 | (_regs)->status32 = STATUS_U_MASK | STATUS_L_MASK \ |
| 99 | | STATUS_E1_MASK | STATUS_E2_MASK; \ |
| 100 | (_regs)->sp = (_usp); \ |
| 101 | /* bogus seed values for debugging */ \ |
| 102 | (_regs)->lp_start = 0x10; \ |
| 103 | (_regs)->lp_end = 0x80; \ |
| 104 | } while (0) |
| 105 | |
| 106 | extern unsigned int get_wchan(struct task_struct *p); |
| 107 | |
| 108 | /* |
| 109 | * Default implementation of macro that returns current |
| 110 | * instruction pointer ("program counter"). |
| 111 | * Should the PC register be read instead ? This macro does not seem to |
| 112 | * be used in many places so this wont be all that bad. |
| 113 | */ |
| 114 | #define current_text_addr() ({ __label__ _l; _l: &&_l; }) |
| 115 | |
| 116 | #endif /* !__ASSEMBLY__ */ |
| 117 | |
| 118 | /* Kernels Virtual memory area. |
| 119 | * Unlike other architectures(MIPS, sh, cris ) ARC 700 does not have a |
| 120 | * "kernel translated" region (like KSEG2 in MIPS). So we use a upper part |
| 121 | * of the translated bottom 2GB for kernel virtual memory and protect |
| 122 | * these pages from user accesses by disabling Ru, Eu and Wu. |
| 123 | */ |
| 124 | #define VMALLOC_SIZE (0x10000000) /* 256M */ |
| 125 | #define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE) |
| 126 | #define VMALLOC_END (PAGE_OFFSET) |
| 127 | |
| 128 | /* Most of the architectures seem to be keeping some kind of padding between |
| 129 | * userspace TASK_SIZE and PAGE_OFFSET. i.e TASK_SIZE != PAGE_OFFSET. |
| 130 | */ |
| 131 | #define USER_KERNEL_GUTTER 0x10000000 |
| 132 | |
| 133 | /* User address space: |
| 134 | * On ARC700, CPU allows the entire lower half of 32 bit address space to be |
| 135 | * translated. Thus potentially 2G (0:0x7FFF_FFFF) could be User vaddr space. |
| 136 | * However we steal 256M for kernel addr (0x7000_0000:0x7FFF_FFFF) and another |
| 137 | * 256M (0x6000_0000:0x6FFF_FFFF) is gutter between user/kernel spaces |
| 138 | * Thus total User vaddr space is (0:0x5FFF_FFFF) |
| 139 | */ |
| 140 | #define TASK_SIZE (PAGE_OFFSET - VMALLOC_SIZE - USER_KERNEL_GUTTER) |
| 141 | |
| 142 | #define STACK_TOP TASK_SIZE |
| 143 | #define STACK_TOP_MAX STACK_TOP |
| 144 | |
| 145 | /* This decides where the kernel will search for a free chunk of vm |
| 146 | * space during mmap's. |
| 147 | */ |
| 148 | #define TASK_UNMAPPED_BASE (TASK_SIZE / 3) |
| 149 | |
| 150 | #endif /* __KERNEL__ */ |
| 151 | |
| 152 | #endif /* __ASM_ARC_PROCESSOR_H */ |