LXR linux/arch/arc/include/asm/processor.h

   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#ifdef CONFIG_ARC_PLAT_EZNPS
  31struct eznps_dp {
  32        unsigned int eflags;
  33        unsigned int gpa1;
  34};
  35#endif
  36
  37/* Arch specific stuff which needs to be saved per task.
  38 * However these items are not so important so as to earn a place in
  39 * struct thread_info
  40 */
  41struct thread_struct {
  42        unsigned long ksp;      /* kernel mode stack pointer */
  43        unsigned long callee_reg;       /* pointer to callee regs */
  44        unsigned long fault_address;    /* dbls as brkpt holder as well */
  45#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
  46        struct arc_fpu fpu;
  47#endif
  48#ifdef CONFIG_ARC_PLAT_EZNPS
  49        struct eznps_dp dp;
  50#endif
  51};
  52
  53#define INIT_THREAD  {                          \
  54        .ksp = sizeof(init_stack) + (unsigned long) init_stack, \
  55}
  56
  57/* Forward declaration, a strange C thing */
  58struct task_struct;
  59
  60#define task_pt_regs(p) \
  61        ((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1)
  62
  63/* Free all resources held by a thread */
  64#define release_thread(thread) do { } while (0)
  65
  66/*
  67 * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise
  68 * get optimised away by gcc
  69 */
  70#ifndef CONFIG_EZNPS_MTM_EXT
  71
  72#define cpu_relax()             barrier()
  73
  74#else
  75
  76#define cpu_relax()     \
  77        __asm__ __volatile__ (".word %0" : : "i"(CTOP_INST_SCHD_RW) : "memory")
  78
  79#endif
  80
  81#define KSTK_EIP(tsk)   (task_pt_regs(tsk)->ret)
  82#define KSTK_ESP(tsk)   (task_pt_regs(tsk)->sp)
  83
  84/*
  85 * Where about of Task's sp, fp, blink when it was last seen in kernel mode.
  86 * Look in process.c for details of kernel stack layout
  87 */
  88#define TSK_K_ESP(tsk)          (tsk->thread.ksp)
  89
  90#define TSK_K_REG(tsk, off)     (*((unsigned long *)(TSK_K_ESP(tsk) + \
  91                                        sizeof(struct callee_regs) + off)))
  92
  93#define TSK_K_BLINK(tsk)        TSK_K_REG(tsk, 4)
  94#define TSK_K_FP(tsk)           TSK_K_REG(tsk, 0)
  95
  96extern void start_thread(struct pt_regs * regs, unsigned long pc,
  97                         unsigned long usp);
  98
  99extern unsigned int get_wchan(struct task_struct *p);
 100
 101/*
 102 * Default implementation of macro that returns current
 103 * instruction pointer ("program counter").
 104 * Should the PC register be read instead ? This macro does not seem to
 105 * be used in many places so this wont be all that bad.
 106 */
 107#define current_text_addr() ({ __label__ _l; _l: &&_l; })
 108
 109#endif /* !__ASSEMBLY__ */
 110
 111/*
 112 * Default System Memory Map on ARC
 113 *
 114 * ---------------------------- (lower 2G, Translated) -------------------------
 115 * 0x0000_0000          0x5FFF_FFFF     (user vaddr: TASK_SIZE)
 116 * 0x6000_0000          0x6FFF_FFFF     (reserved gutter between U/K)
 117 * 0x7000_0000          0x7FFF_FFFF     (kvaddr: vmalloc/modules/pkmap..)
 118 *
 119 * PAGE_OFFSET ---------------- (Upper 2G, Untranslated) -----------------------
 120 * 0x8000_0000          0xBFFF_FFFF     (kernel direct mapped)
 121 * 0xC000_0000          0xFFFF_FFFF     (peripheral uncached space)
 122 * -----------------------------------------------------------------------------
 123 */
 124
 125#define TASK_SIZE       0x60000000
 126
 127#define VMALLOC_START   (PAGE_OFFSET - (CONFIG_ARC_KVADDR_SIZE << 20))
 128
 129/* 1 PGDIR_SIZE each for fixmap/pkmap, 2 PGDIR_SIZE gutter (see asm/highmem.h) */
 130#define VMALLOC_SIZE    ((CONFIG_ARC_KVADDR_SIZE << 20) - PGDIR_SIZE * 4)
 131
 132#define VMALLOC_END     (VMALLOC_START + VMALLOC_SIZE)
 133
 134#define USER_KERNEL_GUTTER    (VMALLOC_START - TASK_SIZE)
 135
 136#ifdef CONFIG_ARC_PLAT_EZNPS
 137/* NPS architecture defines special window of 129M in user address space for
 138 * special memory areas, when accessing this window the MMU do not use TLB.
 139 * Instead MMU direct the access to:
 140 * 0x57f00000:0x57ffffff -- 1M of closely coupled memory (aka CMEM)
 141 * 0x58000000:0x5fffffff -- 16 huge pages, 8M each, with fixed map (aka FMTs)
 142 *
 143 * CMEM - is the fastest memory we got and its size is 16K.
 144 * FMT  - is used to map either to internal/external memory.
 145 * Internal memory is the second fast memory and its size is 16M
 146 * External memory is the biggest memory (16G) and also the slowest.
 147 *
 148 * STACK_TOP need to be PMD align (21bit) that is why we supply 0x57e00000.
 149 */
 150#define STACK_TOP       0x57e00000
 151#else
 152#define STACK_TOP       TASK_SIZE
 153#endif
 154
 155#define STACK_TOP_MAX   STACK_TOP
 156
 157/* This decides where the kernel will search for a free chunk of vm
 158 * space during mmap's.
 159 */
 160#define TASK_UNMAPPED_BASE      (TASK_SIZE / 3)
 161
 162#endif /* __ASM_ARC_PROCESSOR_H */
 163