hal_arch.h

基于ecos的redboot

#define HAL_BREAKINST_THUMB        0xbebe  // illegal instruction currently
#define HAL_BREAKINST_THUMB_SIZE   2

#ifdef __thumb__

# define HAL_BREAKPOINT(_label_)                         \
asm volatile (" .code 16;"                               \
              " .globl  " #_label_ ";"                   \
              #_label_":"                                \
              " .short " _stringify(HAL_BREAKINST_THUMB) \
    );

# define HAL_BREAKINST           HAL_BREAKINST_THUMB
# define HAL_BREAKINST_SIZE      HAL_BREAKINST_THUMB_SIZE
# define HAL_BREAKINST_TYPE      cyg_uint16
#else // __thumb__

#define HAL_BREAKPOINT(_label_)                   \
asm volatile (" .globl  " #_label_ ";"            \
              #_label_":"                         \
              " .word " _stringify(HAL_BREAKINST_ARM) \
    );

//#define HAL_BREAKINST           {0xFE, 0xDE, 0xFF, 0xE7}
#define HAL_BREAKINST            HAL_BREAKINST_ARM
#define HAL_BREAKINST_SIZE       HAL_BREAKINST_ARM_SIZE
#define HAL_BREAKINST_TYPE       cyg_uint32
#endif // __thumb__


extern cyg_uint32 __arm_breakinst;
extern cyg_uint16 __thumb_breakinst;
#define HAL_BREAKINST_ADDR(x) (((x)==2)? \
                              ((void*)&__thumb_breakinst) : \
                              ((void*)&__arm_breakinst))

//--------------------------------------------------------------------------
// Thread register state manipulation for GDB support.

// GDB expects the registers in this structure:
//   r0..r10, fp, ip, sp, lr, pc  - 4 bytes each
//   f0..f7                       - 12 bytes each (N/A on ARM7)
//   fps                          - 4 bytes       (N/A on ARM7)
//   ps                           - 4 bytes

// Translate a stack pointer as saved by the thread context macros above into
// a pointer to a HAL_SavedRegisters structure.
#define HAL_THREAD_GET_SAVED_REGISTERS( _sp_, _regs_ )  \
        (_regs_) = (HAL_SavedRegisters *)(_sp_)

// Copy a set of registers from a HAL_SavedRegisters structure into a
// GDB ordered array.    
#define HAL_GET_GDB_REGISTERS( _aregval_, _regs_ )              \
    CYG_MACRO_START                                             \
    CYG_ADDRWORD *_regval_ = (CYG_ADDRWORD *)(_aregval_);       \
    int _i_;                                                    \
                                                                \
    for( _i_ = 0; _i_ <= 10; _i_++ )                            \
        _regval_[_i_] = (_regs_)->d[_i_];                       \
                                                                \
    _regval_[11] = (_regs_)->fp;                                \
    _regval_[12] = (_regs_)->ip;                                \
    _regval_[13] = (_regs_)->sp;                                \
    _regval_[14] = (_regs_)->lr;                                \
    _regval_[15] = (_regs_)->pc;                                \
    _regval_[25] = (_regs_)->cpsr;                              \
    for( _i_ = 0; _i_ < 8; _i_++ )                              \
        _regval_[_i_+16] = 0;                                   \
    CYG_MACRO_END

// Copy a GDB ordered array into a HAL_SavedRegisters structure.
#define HAL_SET_GDB_REGISTERS( _regs_ , _aregval_ )             \
    CYG_MACRO_START                                             \
    CYG_ADDRWORD *_regval_ = (CYG_ADDRWORD *)(_aregval_);       \
    int _i_;                                                    \
                                                                \
    for( _i_ = 0; _i_ <= 10; _i_++ )                            \
        (_regs_)->d[_i_] = _regval_[_i_];                       \
                                                                \
    (_regs_)->fp = _regval_[11];                                \
    (_regs_)->ip = _regval_[12];                                \
    (_regs_)->sp = _regval_[13];                                \
    (_regs_)->lr = _regval_[14];                                \
    (_regs_)->pc = _regval_[15];                                \
    (_regs_)->cpsr = _regval_[25];                              \
    CYG_MACRO_END

//--------------------------------------------------------------------------
// HAL setjmp

#define CYGARC_JMP_BUF_SIZE 16  // Actually 11, but some room left over

typedef cyg_uint32 hal_jmp_buf[CYGARC_JMP_BUF_SIZE];

externC int hal_setjmp(hal_jmp_buf env);
externC void hal_longjmp(hal_jmp_buf env, int val);


//--------------------------------------------------------------------------
// Idle thread code.
// This macro is called in the idle thread loop, and gives the HAL the
// chance to insert code. Typical idle thread behaviour might be to halt the
// processor.

externC void hal_idle_thread_action(cyg_uint32 loop_count);

#define HAL_IDLE_THREAD_ACTION(_count_) hal_idle_thread_action(_count_)

//---------------------------------------------------------------------------
// Table definition macros.
// The ARM assembler has a slightly different syntax for some of this, so
// we have to define alternatives here.
// Note that the __string() and __xstring() macros used here are defined in
// hal_tables.h.

#ifndef CYG_HAL_TABLE_BEGIN
#define CYG_HAL_TABLE_BEGIN( _label, _name )                                    \
__asm__(".section \"" __string(.ecos.table.##_name##.begin) "\",\"aw\"\n"       \
	".globl " __xstring(CYG_LABEL_DEFN(_label)) "\n"                        \
	".type    " __xstring(CYG_LABEL_DEFN(_label)) ",object\n"               \
	".p2align 2\n"                                                          \
__xstring(CYG_LABEL_DEFN(_label)) ":\n"                                         \
	".previous\n"                                                           \
       )
#endif

#ifndef CYG_HAL_TABLE_END
#define CYG_HAL_TABLE_END( _label, _name )                                      \
__asm__(".section \"" __string(.ecos.table.##_name##.finish) "\",\"aw\"\n"      \
	".globl " __xstring(CYG_LABEL_DEFN(_label)) "\n"                        \
	".type    " __xstring(CYG_LABEL_DEFN(_label)) ",object\n"               \
	".p2align 2\n"                                                          \
__xstring(CYG_LABEL_DEFN(_label)) ":\n"                                         \
	".previous\n"                                                           \
       )
#endif

//---------------------------------------------------------------------------

// Minimal and sensible stack sizes: the intention is that applications
// will use these to provide a stack size in the first instance prior to
// proper analysis.  Idle thread stack should be this big.

//    THESE ARE NOT INTENDED TO BE MICROMETRICALLY ACCURATE FIGURES.
//           THEY ARE HOWEVER ENOUGH TO START PROGRAMMING.
// YOU MUST MAKE YOUR STACKS LARGER IF YOU HAVE LARGE "AUTO" VARIABLES!

// This is not a config option because it should not be adjusted except
// under "enough rope" sort of disclaimers.

// A minimal, optimized stack frame, rounded up - no autos
#define CYGNUM_HAL_STACK_FRAME_SIZE (4 * 20)

// Stack needed for a context switch: this is implicit in the estimate for
// interrupts so not explicitly used below:
#define CYGNUM_HAL_STACK_CONTEXT_SIZE (4 * 20)

// Interrupt + call to ISR, interrupt_end() and the DSR
#define CYGNUM_HAL_STACK_INTERRUPT_SIZE \
    ((4 * 20) + 2 * CYGNUM_HAL_STACK_FRAME_SIZE)

// Space for the maximum number of nested interrupts, plus room to call functions
#define CYGNUM_HAL_MAX_INTERRUPT_NESTING 4

#define CYGNUM_HAL_STACK_SIZE_MINIMUM \
        (CYGNUM_HAL_MAX_INTERRUPT_NESTING * CYGNUM_HAL_STACK_INTERRUPT_SIZE + \
         2 * CYGNUM_HAL_STACK_FRAME_SIZE)

#define CYGNUM_HAL_STACK_SIZE_TYPICAL \
        (CYGNUM_HAL_STACK_SIZE_MINIMUM + \
         16 * CYGNUM_HAL_STACK_FRAME_SIZE)

//--------------------------------------------------------------------------
// Macros for switching context between two eCos instances (jump from
// code in ROM to code in RAM or vice versa).
#define CYGARC_HAL_SAVE_GP()
#define CYGARC_HAL_RESTORE_GP()

#endif // CYGONCE_HAL_ARCH_H
// End of hal_arch.h