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
  19 static 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
  27 static inline void wrusp(unsigned long usp)
  28 {
  29         __asm__ __volatile__("usp = %0;\n\t"::"da"(usp));
  30 }
  31
  32 static 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
  53 struct 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
  67 extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
  68                                                unsigned long new_sp);
  69
  70 /* Forward declaration, a strange C thing */
  71 struct task_struct;
  72
  73 /* Free all resources held by a thread. */
  74 static inline void release_thread(struct task_struct *dead_task)
  75 {
  76 }
  77
  78 /*
  79  * Free current thread data structures etc..
  80  */
  81 static inline void exit_thread(void)
  82 {
  83 }
  84
  85 /*
  86  * Return saved PC of a blocked thread.
  87  */
  88 #define thread_saved_pc(tsk)    (tsk->thread.pc)
  89
  90 unsigned long get_wchan(struct task_struct *p);
  91
  92 #define KSTK_EIP(tsk)                                                   \
  93     ({                                                                  \
  94         unsigned long eip = 0;                                          \
  95         if ((tsk)->thread.esp0 > PAGE_SIZE &&                           \
  96             MAP_NR((tsk)->thread.esp0) < max_mapnr)                     \
  97               eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc;        \
  98         eip; })
  99 #define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
 100
 101 #define cpu_relax()     smp_mb()
 102 #define cpu_relax_lowlatency() cpu_relax()
 103
 104 /* Get the Silicon Revision of the chip */
 105 static inline uint32_t __pure bfin_revid(void)
 106 {
 107         /* Always use CHIPID, to work around ANOMALY_05000234 */
 108         uint32_t revid = (bfin_read_CHIPID() & CHIPID_VERSION) >> 28;
 109
 110 #ifdef _BOOTROM_GET_DXE_ADDRESS_TWI
 111         /*
 112          * ANOMALY_05000364
 113          * Incorrect Revision Number in DSPID Register
 114          */
 115         if (ANOMALY_05000364 &&
 116             bfin_read16(_BOOTROM_GET_DXE_ADDRESS_TWI) == 0x2796)
 117                 revid = 1;
 118 #endif
 119
 120         return revid;
 121 }
 122
 123 static inline uint16_t __pure bfin_cpuid(void)
 124 {
 125         return (bfin_read_CHIPID() & CHIPID_FAMILY) >> 12;
 126 }
 127
 128 static inline uint32_t __pure bfin_dspid(void)
 129 {
 130         return bfin_read_DSPID();
 131 }
 132
 133 #define blackfin_core_id() (bfin_dspid() & 0xff)
 134
 135 static inline uint32_t __pure bfin_compiled_revid(void)
 136 {
 137 #if defined(CONFIG_BF_REV_0_0)
 138         return 0;
 139 #elif defined(CONFIG_BF_REV_0_1)
 140         return 1;
 141 #elif defined(CONFIG_BF_REV_0_2)
 142         return 2;
 143 #elif defined(CONFIG_BF_REV_0_3)
 144         return 3;
 145 #elif defined(CONFIG_BF_REV_0_4)
 146         return 4;
 147 #elif defined(CONFIG_BF_REV_0_5)
 148         return 5;
 149 #elif defined(CONFIG_BF_REV_0_6)
 150         return 6;
 151 #elif defined(CONFIG_BF_REV_ANY)
 152         return 0xffff;
 153 #else
 154         return -1;
 155 #endif
 156 }
 157
 158 #endif