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 static inline unsigned long __get_SP(void)
  28 {
  29         unsigned long sp;
  30
  31         __asm__ __volatile__("%0 = sp;\n\t" : "=da"(sp));
  32         return sp;
  33 }
  34
  35 /*
  36  * User space process size: 1st byte beyond user address space.
  37  * Fairly meaningless on nommu.  Parts of user programs can be scattered
  38  * in a lot of places, so just disable this by setting it to 0xFFFFFFFF.
  39  */
  40 #define TASK_SIZE       0xFFFFFFFF
  41
  42 #ifdef __KERNEL__
  43 #define STACK_TOP       TASK_SIZE
  44 #endif
  45
  46 #define TASK_UNMAPPED_BASE      0
  47
  48 struct thread_struct {
  49         unsigned long ksp;      /* kernel stack pointer */
  50         unsigned long usp;      /* user stack pointer */
  51         unsigned short seqstat; /* saved status register */
  52         unsigned long esp0;     /* points to SR of stack frame pt_regs */
  53         unsigned long pc;       /* instruction pointer */
  54         void *        debuggerinfo;
  55 };
  56
  57 #define INIT_THREAD  {                                          \
  58         sizeof(init_stack) + (unsigned long) init_stack, 0,     \
  59         PS_S, 0, 0                                              \
  60 }
  61
  62 /*
  63  * Do necessary setup to start up a newly executed thread.
  64  *
  65  * pass the data segment into user programs if it exists,
  66  * it can't hurt anything as far as I can tell
  67  */
  68 #ifndef CONFIG_SMP
  69 #define start_thread(_regs, _pc, _usp)                                  \
  70 do {                                                                    \
  71         set_fs(USER_DS);                                                \
  72         (_regs)->pc = (_pc);                                            \
  73         if (current->mm)                                                \
  74                 (_regs)->p5 = current->mm->start_data;                  \
  75         task_thread_info(current)->l1_task_info.stack_start             \
  76                 = (void *)current->mm->context.stack_start;             \
  77         task_thread_info(current)->l1_task_info.lowest_sp = (void *)(_usp); \
  78         memcpy(L1_SCRATCH_TASK_INFO, &task_thread_info(current)->l1_task_info, \
  79                 sizeof(*L1_SCRATCH_TASK_INFO));                         \
  80         wrusp(_usp);                                                    \
  81 } while(0)
  82 #else
  83 #define start_thread(_regs, _pc, _usp)                                  \
  84 do {                                                                    \
  85         set_fs(USER_DS);                                                \
  86         (_regs)->pc = (_pc);                                            \
  87         if (current->mm)                                                \
  88                 (_regs)->p5 = current->mm->start_data;                  \
  89         wrusp(_usp);                                                    \
  90 } while (0)
  91 #endif
  92
  93 /* Forward declaration, a strange C thing */
  94 struct task_struct;
  95
  96 /* Free all resources held by a thread. */
  97 static inline void release_thread(struct task_struct *dead_task)
  98 {
  99 }
 100
 101 #define prepare_to_copy(tsk)    do { } while (0)
 102
 103 extern int kernel_thread(int (*fn) (void *), void *arg, unsigned long flags);
 104
 105 /*
 106  * Free current thread data structures etc..
 107  */
 108 static inline void exit_thread(void)
 109 {
 110 }
 111
 112 /*
 113  * Return saved PC of a blocked thread.
 114  */
 115 #define thread_saved_pc(tsk)    (tsk->thread.pc)
 116
 117 unsigned long get_wchan(struct task_struct *p);
 118
 119 #define KSTK_EIP(tsk)                                                   \
 120     ({                                                                  \
 121         unsigned long eip = 0;                                          \
 122         if ((tsk)->thread.esp0 > PAGE_SIZE &&                           \
 123             MAP_NR((tsk)->thread.esp0) < max_mapnr)                     \
 124               eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc;        \
 125         eip; })
 126 #define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
 127
 128 #define cpu_relax()     smp_mb()
 129
 130
 131 /* Get the Silicon Revision of the chip */
 132 static inline uint32_t __pure bfin_revid(void)
 133 {
 134         /* stored in the upper 4 bits */
 135         uint32_t revid = bfin_read_CHIPID() >> 28;
 136
 137 #ifdef CONFIG_BF52x
 138         /* ANOMALY_05000357
 139          * Incorrect Revision Number in DSPID Register
 140          */
 141         if (revid == 0)
 142                 switch (bfin_read16(_BOOTROM_GET_DXE_ADDRESS_TWI)) {
 143                 case 0x0010:
 144                         revid = 0;
 145                         break;
 146                 case 0x2796:
 147                         revid = 1;
 148                         break;
 149                 default:
 150                         revid = 0xFFFF;
 151                         break;
 152                 }
 153 #endif
 154         return revid;
 155 }
 156
 157 static inline uint16_t __pure bfin_cpuid(void)
 158 {
 159         return (bfin_read_CHIPID() & CHIPID_FAMILY) >> 12;
 160 }
 161
 162 static inline uint32_t __pure bfin_dspid(void)
 163 {
 164         return bfin_read_DSPID();
 165 }
 166
 167 static inline uint32_t __pure bfin_compiled_revid(void)
 168 {
 169 #if defined(CONFIG_BF_REV_0_0)
 170         return 0;
 171 #elif defined(CONFIG_BF_REV_0_1)
 172         return 1;
 173 #elif defined(CONFIG_BF_REV_0_2)
 174         return 2;
 175 #elif defined(CONFIG_BF_REV_0_3)
 176         return 3;
 177 #elif defined(CONFIG_BF_REV_0_4)
 178         return 4;
 179 #elif defined(CONFIG_BF_REV_0_5)
 180         return 5;
 181 #elif defined(CONFIG_BF_REV_0_6)
 182         return 6;
 183 #elif defined(CONFIG_BF_REV_ANY)
 184         return 0xffff;
 185 #else
 186         return -1;
 187 #endif
 188 }
 189
 190 #endif