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

   1/*
   2 * Copyright 2004-2009 Analog Devices Inc.
   3 *
   4 * Licensed under the GPL-2 or later.
   5 */
   6
   7#ifndef __ASM_BFIN_PROCESSOR_H
   8#define __ASM_BFIN_PROCESSOR_H
   9
  10/*
  11 * Default implementation of macro that returns current
  12 * instruction pointer ("program counter").
  13 */
  14#define current_text_addr() ({ __label__ _l; _l: &&_l;})
  15
  16#include <asm/ptrace.h>
  17#include <mach/blackfin.h>
  18
  19static inline unsigned long rdusp(void)
  20{
  21        unsigned long usp;
  22
  23        __asm__ __volatile__("%0 = usp;\n\t":"=da"(usp));
  24        return usp;
  25}
  26
  27static inline void wrusp(unsigned long usp)
  28{
  29        __asm__ __volatile__("usp = %0;\n\t"::"da"(usp));
  30}
  31
  32static inline unsigned long __get_SP(void)
  33{
  34        unsigned long sp;
  35
  36        __asm__ __volatile__("%0 = sp;\n\t" : "=da"(sp));
  37        return sp;
  38}
  39
  40/*
  41 * User space process size: 1st byte beyond user address space.
  42 * Fairly meaningless on nommu.  Parts of user programs can be scattered
  43 * in a lot of places, so just disable this by setting it to 0xFFFFFFFF.
  44 */
  45#define TASK_SIZE       0xFFFFFFFF
  46
  47#ifdef __KERNEL__
  48#define STACK_TOP       TASK_SIZE
  49#endif
  50
  51#define TASK_UNMAPPED_BASE      0
  52
  53struct thread_struct {
  54        unsigned long ksp;      /* kernel stack pointer */
  55        unsigned long usp;      /* user stack pointer */
  56        unsigned short seqstat; /* saved status register */
  57        unsigned long esp0;     /* points to SR of stack frame pt_regs */
  58        unsigned long pc;       /* instruction pointer */
  59        void *        debuggerinfo;
  60};
  61
  62#define INIT_THREAD  {                                          \
  63        sizeof(init_stack) + (unsigned long) init_stack, 0,     \
  64        PS_S, 0, 0                                              \
  65}
  66
  67extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
  68                                               unsigned long new_sp);
  69
  70/* Forward declaration, a strange C thing */
  71struct task_struct;
  72
  73/* Free all resources held by a thread. */
  74static inline void release_thread(struct task_struct *dead_task)
  75{
  76}
  77
  78/*
  79 * Return saved PC of a blocked thread.
  80 */
  81#define thread_saved_pc(tsk)    (tsk->thread.pc)
  82
  83unsigned long get_wchan(struct task_struct *p);
  84
  85#define KSTK_EIP(tsk)                                                   \
  86    ({                                                                  \
  87        unsigned long eip = 0;                                          \
  88        if ((tsk)->thread.esp0 > PAGE_SIZE &&                           \
  89            MAP_NR((tsk)->thread.esp0) < max_mapnr)                     \
  90              eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc;        \
  91        eip; })
  92#define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
  93
  94#define cpu_relax()     smp_mb()
  95#define cpu_relax_lowlatency() cpu_relax()
  96
  97/* Get the Silicon Revision of the chip */
  98static inline uint32_t __pure bfin_revid(void)
  99{
 100        /* Always use CHIPID, to work around ANOMALY_05000234 */
 101        uint32_t revid = (bfin_read_CHIPID() & CHIPID_VERSION) >> 28;
 102
 103#ifdef _BOOTROM_GET_DXE_ADDRESS_TWI
 104        /*
 105         * ANOMALY_05000364
 106         * Incorrect Revision Number in DSPID Register
 107         */
 108        if (ANOMALY_05000364 &&
 109            bfin_read16(_BOOTROM_GET_DXE_ADDRESS_TWI) == 0x2796)
 110                revid = 1;
 111#endif
 112
 113        return revid;
 114}
 115
 116static inline uint16_t __pure bfin_cpuid(void)
 117{
 118        return (bfin_read_CHIPID() & CHIPID_FAMILY) >> 12;
 119}
 120
 121static inline uint32_t __pure bfin_dspid(void)
 122{
 123        return bfin_read_DSPID();
 124}
 125
 126#define blackfin_core_id() (bfin_dspid() & 0xff)
 127
 128static inline uint32_t __pure bfin_compiled_revid(void)
 129{
 130#if defined(CONFIG_BF_REV_0_0)
 131        return 0;
 132#elif defined(CONFIG_BF_REV_0_1)
 133        return 1;
 134#elif defined(CONFIG_BF_REV_0_2)
 135        return 2;
 136#elif defined(CONFIG_BF_REV_0_3)
 137        return 3;
 138#elif defined(CONFIG_BF_REV_0_4)
 139        return 4;
 140#elif defined(CONFIG_BF_REV_0_5)
 141        return 5;
 142#elif defined(CONFIG_BF_REV_0_6)
 143        return 6;
 144#elif defined(CONFIG_BF_REV_ANY)
 145        return 0xffff;
 146#else
 147        return -1;
 148#endif
 149}
 150
 151#endif
 152