arch/blackfin/include/asm/processor.h

   1 #ifndef __ASM_BFIN_PROCESSOR_H
   2 #define __ASM_BFIN_PROCESSOR_H
   3
   4 /*
   5  * Default implementation of macro that returns current
   6  * instruction pointer ("program counter").
   7  */
   8 #define current_text_addr() ({ __label__ _l; _l: &&_l;})
   9
  10 #include <asm/blackfin.h>
  11 #include <asm/segment.h>
  12 #include <linux/compiler.h>
  13
  14 static inline unsigned long rdusp(void)
  15 {
  16         unsigned long usp;
  17
  18         __asm__ __volatile__("%0 = usp;\n\t":"=da"(usp));
  19         return usp;
  20 }
  21
  22 static inline void wrusp(unsigned long usp)
  23 {
  24         __asm__ __volatile__("usp = %0;\n\t"::"da"(usp));
  25 }
  26
  27 /*
  28  * User space process size: 1st byte beyond user address space.
  29  * Fairly meaningless on nommu.  Parts of user programs can be scattered
  30  * in a lot of places, so just disable this by setting it to 0xFFFFFFFF.
  31  */
  32 #define TASK_SIZE       0xFFFFFFFF
  33
  34 #ifdef __KERNEL__
  35 #define STACK_TOP       TASK_SIZE
  36 #endif
  37
  38 #define TASK_UNMAPPED_BASE      0
  39
  40 struct thread_struct {
  41         unsigned long ksp;      /* kernel stack pointer */
  42         unsigned long usp;      /* user stack pointer */
  43         unsigned short seqstat; /* saved status register */
  44         unsigned long esp0;     /* points to SR of stack frame pt_regs */
  45         unsigned long pc;       /* instruction pointer */
  46         void *        debuggerinfo;
  47 };
  48
  49 #define INIT_THREAD  {                                          \
  50         sizeof(init_stack) + (unsigned long) init_stack, 0,     \
  51         PS_S, 0, 0                                              \
  52 }
  53
  54 /*
  55  * Do necessary setup to start up a newly executed thread.
  56  *
  57  * pass the data segment into user programs if it exists,
  58  * it can't hurt anything as far as I can tell
  59  */
  60 #define start_thread(_regs, _pc, _usp)                                  \
  61 do {                                                                    \
  62         set_fs(USER_DS);                                                \
  63         (_regs)->pc = (_pc);                                            \
  64         if (current->mm)                                                \
  65                 (_regs)->p5 = current->mm->start_data;                  \
  66         task_thread_info(current)->l1_task_info.stack_start             \
  67                 = (void *)current->mm->context.stack_start;             \
  68         task_thread_info(current)->l1_task_info.lowest_sp = (void *)(_usp); \
  69         memcpy(L1_SCRATCH_TASK_INFO, &task_thread_info(current)->l1_task_info, \
  70                 sizeof(*L1_SCRATCH_TASK_INFO));                         \
  71         wrusp(_usp);                                                    \
  72 } while(0)
  73
  74 /* Forward declaration, a strange C thing */
  75 struct task_struct;
  76
  77 /* Free all resources held by a thread. */
  78 static inline void release_thread(struct task_struct *dead_task)
  79 {
  80 }
  81
  82 #define prepare_to_copy(tsk)    do { } while (0)
  83
  84 extern int kernel_thread(int (*fn) (void *), void *arg, unsigned long flags);
  85
  86 /*
  87  * Free current thread data structures etc..
  88  */
  89 static inline void exit_thread(void)
  90 {
  91 }
  92
  93 /*
  94  * Return saved PC of a blocked thread.
  95  */
  96 #define thread_saved_pc(tsk)    (tsk->thread.pc)
  97
  98 unsigned long get_wchan(struct task_struct *p);
  99
 100 #define KSTK_EIP(tsk)                                                   \
 101     ({                                                                  \
 102         unsigned long eip = 0;                                          \
 103         if ((tsk)->thread.esp0 > PAGE_SIZE &&                           \
 104             MAP_NR((tsk)->thread.esp0) < max_mapnr)                     \
 105               eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc;        \
 106         eip; })
 107 #define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
 108
 109 #define cpu_relax()     barrier()
 110
 111 /* Get the Silicon Revision of the chip */
 112 static inline uint32_t __pure bfin_revid(void)
 113 {
 114         /* stored in the upper 4 bits */
 115         uint32_t revid = bfin_read_CHIPID() >> 28;
 116
 117 #ifdef CONFIG_BF52x
 118         /* ANOMALY_05000357
 119          * Incorrect Revision Number in DSPID Register
 120          */
 121         if (revid == 0)
 122                 switch (bfin_read16(_BOOTROM_GET_DXE_ADDRESS_TWI)) {
 123                 case 0x0010:
 124                         revid = 0;
 125                         break;
 126                 case 0x2796:
 127                         revid = 1;
 128                         break;
 129                 default:
 130                         revid = 0xFFFF;
 131                         break;
 132                 }
 133 #endif
 134         return revid;
 135 }
 136
 137 static inline uint32_t __pure bfin_compiled_revid(void)
 138 {
 139 #if defined(CONFIG_BF_REV_0_0)
 140         return 0;
 141 #elif defined(CONFIG_BF_REV_0_1)
 142         return 1;
 143 #elif defined(CONFIG_BF_REV_0_2)
 144         return 2;
 145 #elif defined(CONFIG_BF_REV_0_3)
 146         return 3;
 147 #elif defined(CONFIG_BF_REV_0_4)
 148         return 4;
 149 #elif defined(CONFIG_BF_REV_0_5)
 150         return 5;
 151 #elif defined(CONFIG_BF_REV_ANY)
 152         return 0xffff;
 153 #else
 154         return -1;
 155 #endif
 156 }
 157
 158 #endif