LXR linux/arch/c6x/include/asm/processor.h

   1/*
   2 *  Port on Texas Instruments TMS320C6x architecture
   3 *
   4 *  Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
   5 *  Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
   6 *
   7 *  Updated for 2.6.34: Mark Salter <msalter@redhat.com>
   8 *
   9 *  This program is free software; you can redistribute it and/or modify
  10 *  it under the terms of the GNU General Public License version 2 as
  11 *  published by the Free Software Foundation.
  12 */
  13#ifndef _ASM_C6X_PROCESSOR_H
  14#define _ASM_C6X_PROCESSOR_H
  15
  16#include <asm/ptrace.h>
  17#include <asm/page.h>
  18#include <asm/current.h>
  19
  20/*
  21 * Default implementation of macro that returns current
  22 * instruction pointer ("program counter").
  23 */
  24#define current_text_addr()                     \
  25({                                              \
  26        void *__pc;                             \
  27        asm("mvc .S2 pce1,%0\n" : "=b"(__pc));  \
  28        __pc;                                   \
  29})
  30
  31/*
  32 * User space process size. This is mostly meaningless for NOMMU
  33 * but some C6X processors may have RAM addresses up to 0xFFFFFFFF.
  34 * Since calls like mmap() can return an address or an error, we
  35 * have to allow room for error returns when code does something
  36 * like:
  37 *
  38 *       addr = do_mmap(...)
  39 *       if ((unsigned long)addr >= TASK_SIZE)
  40 *            ... its an error code, not an address ...
  41 *
  42 * Here, we allow for 4096 error codes which means we really can't
  43 * use the last 4K page on systems with RAM extending all the way
  44 * to the end of the 32-bit address space.
  45 */
  46#define TASK_SIZE       0xFFFFF000
  47
  48/*
  49 * This decides where the kernel will search for a free chunk of vm
  50 * space during mmap's. We won't be using it
  51 */
  52#define TASK_UNMAPPED_BASE      0
  53
  54struct thread_struct {
  55        unsigned long long b15_14;
  56        unsigned long long a15_14;
  57        unsigned long long b13_12;
  58        unsigned long long a13_12;
  59        unsigned long long b11_10;
  60        unsigned long long a11_10;
  61        unsigned long long ricl_icl;
  62        unsigned long  usp;             /* user stack pointer */
  63        unsigned long  pc;              /* kernel pc */
  64        unsigned long  wchan;
  65};
  66
  67#define INIT_THREAD                                     \
  68{                                                       \
  69        .usp = 0,                                       \
  70        .wchan = 0,                                     \
  71}
  72
  73#define INIT_MMAP { \
  74        &init_mm, 0, 0, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, \
  75        NULL, NULL }
  76
  77#define task_pt_regs(task) \
  78        ((struct pt_regs *)(THREAD_START_SP + task_stack_page(task)) - 1)
  79
  80#define alloc_kernel_stack()    __get_free_page(GFP_KERNEL)
  81#define free_kernel_stack(page) free_page((page))
  82
  83
  84/* Forward declaration, a strange C thing */
  85struct task_struct;
  86
  87extern void start_thread(struct pt_regs *regs, unsigned int pc,
  88                         unsigned long usp);
  89
  90/* Free all resources held by a thread. */
  91static inline void release_thread(struct task_struct *dead_task)
  92{
  93}
  94
  95#define copy_segments(tsk, mm)          do { } while (0)
  96#define release_segments(mm)            do { } while (0)
  97
  98/*
  99 * saved PC of a blocked thread.
 100 */
 101#define thread_saved_pc(tsk) (task_pt_regs(tsk)->pc)
 102
 103/*
 104 * saved kernel SP and DP of a blocked thread.
 105 */
 106#ifdef _BIG_ENDIAN
 107#define thread_saved_ksp(tsk) \
 108        (*(unsigned long *)&(tsk)->thread.b15_14)
 109#define thread_saved_dp(tsk) \
 110        (*(((unsigned long *)&(tsk)->thread.b15_14) + 1))
 111#else
 112#define thread_saved_ksp(tsk) \
 113        (*(((unsigned long *)&(tsk)->thread.b15_14) + 1))
 114#define thread_saved_dp(tsk) \
 115        (*(unsigned long *)&(tsk)->thread.b15_14)
 116#endif
 117
 118extern unsigned long get_wchan(struct task_struct *p);
 119
 120#define KSTK_EIP(task)  (task_pt_regs(task)->pc)
 121#define KSTK_ESP(task)  (task_pt_regs(task)->sp)
 122
 123#define cpu_relax()             do { } while (0)
 124
 125extern const struct seq_operations cpuinfo_op;
 126
 127/* Reset the board */
 128#define HARD_RESET_NOW()
 129
 130extern unsigned int c6x_core_freq;
 131
 132
 133extern void (*c6x_restart)(void);
 134extern void (*c6x_halt)(void);
 135
 136#endif /* ASM_C6X_PROCESSOR_H */
 137