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#ifndef CYGONCE_HAL_ARCH_H

#define CYGONCE_HAL_ARCH_H

//=============================================================================

//

//      hal_arch.h

//

//      Architecture specific abstractions

//

//=============================================================================

//####ECOSGPLCOPYRIGHTBEGIN####

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

// This file is part of eCos, the Embedded Configurable Operating System.

// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.

//

// eCos is free software; you can redistribute it and/or modify it under

// the terms of the GNU General Public License as published by the Free

// Software Foundation; either version 2 or (at your option) any later version.

//

// eCos is distributed in the hope that it will be useful, but WITHOUT ANY

// WARRANTY; without even the implied warranty of MERCHANTABILITY or

// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

// for more details.

//

// You should have received a copy of the GNU General Public License along

// with eCos; if not, write to the Free Software Foundation, Inc.,

// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.

//

// As a special exception, if other files instantiate templates or use macros

// or inline functions from this file, or you compile this file and link it

// with other works to produce a work based on this file, this file does not

// by itself cause the resulting work to be covered by the GNU General Public

// License. However the source code for this file must still be made available

// in accordance with section (3) of the GNU General Public License.

//

// This exception does not invalidate any other reasons why a work based on

// this file might be covered by the GNU General Public License.

//

// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.

// at http://sources.redhat.com/ecos/ecos-license/

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

//####ECOSGPLCOPYRIGHTEND####

//=============================================================================

//#####DESCRIPTIONBEGIN####

//

// Author(s):   nickg

// Contributors:  nickg

// Date:        1997-09-08

// Purpose:     Define architecture abstractions

// Usage:       #include <cyg/hal/hal_arch.h>

//              

//####DESCRIPTIONEND####

//

//=============================================================================

#include <pkgconf/hal.h>

#include <cyg/infra/cyg_type.h>

#include <cyg/hal/ppc_regs.h>           // CYGARC_REG_MSR_EE

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

// Processor saved states:

typedef struct

{

#ifdef CYGDBG_HAL_POWERPC_FRAME_WALLS

    cyg_uint32   wall_head;

#endif

    // These are common to all saved states

    cyg_uint32   d[32];                 // Data regs

#ifdef CYGHWR_HAL_POWERPC_FPU

    double       f[32];                 // Floating point registers

#endif   

    cyg_uint32   cr;                    // Condition Reg

    cyg_uint32   xer;                   // XER

    cyg_uint32   lr;                    // Link Reg

    cyg_uint32   ctr;                   // Count Reg

    // These are saved for exceptions and interrupts, but may also

    // be saved in a context switch if thread-aware debugging is enabled.

    cyg_uint32   msr;                   // Machine State Reg

    cyg_uint32   pc;                    // Program Counter

    // This marks the limit of state saved during a context switch and

    // is used to calculate necessary stack allocation for context switches.

    // It would probably be better to have a union instead...

    cyg_uint32   context_size[0];

    // These are only saved for exceptions and interrupts

    cyg_uint32   vector;                // Vector number

#ifdef CYGDBG_HAL_POWERPC_FRAME_WALLS

    cyg_uint32   wall_tail;

#endif

} HAL_SavedRegisters;

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

// Exception handling function.

// This function is defined by the kernel according to this prototype. It is

// invoked from the HAL to deal with any CPU exceptions that the HAL does

// not want to deal with itself. It usually invokes the kernel's exception

// delivery mechanism.

externC void cyg_hal_deliver_exception( CYG_WORD code, CYG_ADDRWORD data );

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

// Bit manipulation macros

#define HAL_LSBIT_INDEX(index, mask)    \

    asm ( "neg    11,%1;"               \

          "and    11,11,%1;"            \

          "cntlzw %0,11;"               \

          "subfic %0,%0,31;"            \

          : "=r" (index)                \

          : "r" (mask)                  \

          : "r11"                       \

        );

#define HAL_MSBIT_INDEX(index, mask)            \

    asm ( "cntlzw %0,%1\n"                      \

          "subfic %0,%0,31;"                    \

          : "=r" (index)                        \

          : "r" (mask)                          \

        );

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

// eABI

#define CYGARC_PPC_STACK_FRAME_SIZE     56      // size of a stack frame

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

// Context Initialization

// Initialize the context of a thread.

// Arguments:

// _sparg_ name of variable containing current sp, will be written with new sp

// _thread_ thread object address, passed as argument to entry point

// _entry_ entry point address.

// _id_ bit pattern used in initializing registers, for debugging.

#define HAL_THREAD_INIT_CONTEXT( _sparg_, _thread_, _entry_, _id_ )           \

    CYG_MACRO_START                                                           \

    register CYG_WORD _sp_ = (((CYG_WORD)_sparg_) &~15)                       \

                                 - CYGARC_PPC_STACK_FRAME_SIZE;               \

    register HAL_SavedRegisters *_regs_;                                      \

    int _i_;                                                                  \

    _regs_ = (HAL_SavedRegisters *)((_sp_) - sizeof(HAL_SavedRegisters));     \

    for( _i_ = 0; _i_ < 32; _i_++ ) (_regs_)->d[_i_] = (_id_)|_i_;            \

    (_regs_)->d[01] = (CYG_WORD)(_sp_);        /* SP = top of stack      */   \

    (_regs_)->d[03] = (CYG_WORD)(_thread_);    /* R3 = arg1 = thread ptr */   \

    (_regs_)->cr = 0;                          /* CR = 0                 */   \

    (_regs_)->xer = 0;                         /* XER = 0                */   \

    (_regs_)->lr = (CYG_WORD)(_entry_);        /* LR = entry point       */   \

    (_regs_)->pc = (CYG_WORD)(_entry_);        /* set PC for thread dbg  */   \

    (_regs_)->ctr = 0;                         /* CTR = 0                */   \

    (_regs_)->msr = CYGARC_REG_MSR_EE;         /* MSR = enable irqs      */   \

    _sparg_ = (CYG_ADDRESS)_regs_;                                            \

    CYG_MACRO_END

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

// Context switch macros.

// The arguments are pointers to locations where the stack pointer

// of the current thread is to be stored, and from where the sp of the

// next thread is to be fetched.

externC void hal_thread_switch_context( CYG_ADDRESS to, CYG_ADDRESS from );

externC void hal_thread_load_context( CYG_ADDRESS to )

    __attribute__ ((noreturn));

#define HAL_THREAD_SWITCH_CONTEXT(_fspptr_,_tspptr_)                    \

        hal_thread_switch_context((CYG_ADDRESS)_tspptr_,(CYG_ADDRESS)_fspptr_);

#define HAL_THREAD_LOAD_CONTEXT(_tspptr_)                               \

        hal_thread_load_context( (CYG_ADDRESS)_tspptr_ );

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

// Execution reorder barrier.

// When optimizing the compiler can reorder code. In multithreaded systems

// where the order of actions is vital, this can sometimes cause problems.

// This macro may be inserted into places where reordering should not happen.

#define HAL_REORDER_BARRIER() asm volatile ( "" : : : "memory" )

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

// Breakpoint support

// HAL_BREAKPOINT() is a code sequence that will cause a breakpoint to happen

// if executed.

// HAL_BREAKINST is the value of the breakpoint instruction and 

// HAL_BREAKINST_SIZE is its size in bytes.

#define HAL_BREAKPOINT(_label_)                 \

asm volatile (" .globl  " #_label_ ";"          \

              #_label_":"                       \

              " trap"                           \

    );

#define HAL_BREAKINST           0x7d821008

#define HAL_BREAKINST_SIZE      4

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

// Thread register state manipulation for GDB support.

// 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_ < 32; _i_++ )                             \

        _regval_[_i_] = (_regs_)->d[_i_];                       \

                                                                \

    _regval_[64] = (_regs_)->pc;                                \

    _regval_[65] = (_regs_)->msr;                               \

    _regval_[66] = (_regs_)->cr;                                \

    _regval_[67] = (_regs_)->lr;                                \

    _regval_[68] = (_regs_)->ctr;                               \

    _regval_[69] = (_regs_)->xer;                               \

    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_ < 32; _i_++ )                             \

        (_regs_)->d[_i_] = _regval_[_i_];                       \

                                                                \

    (_regs_)->pc  = _regval_[64];                               \

    (_regs_)->msr = _regval_[65];                               \

    (_regs_)->cr  = _regval_[66];                               \

    (_regs_)->lr  = _regval_[67];                               \

    (_regs_)->ctr = _regval_[68];                               \

    (_regs_)->xer = _regval_[69];                               \

    CYG_MACRO_END

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

// HAL setjmp

typedef struct {

    cyg_uint32 sp;

    cyg_uint32 r2;

    cyg_uint32 r13;

    cyg_uint32 r14;

    cyg_uint32 r15;

    cyg_uint32 r16;

    cyg_uint32 r17;

    cyg_uint32 r18;

    cyg_uint32 r19;

    cyg_uint32 r20;

    cyg_uint32 r21;

    cyg_uint32 r22;

    cyg_uint32 r23;

    cyg_uint32 r24;

    cyg_uint32 r25;

    cyg_uint32 r26;

    cyg_uint32 r27;

    cyg_uint32 r28;

    cyg_uint32 r29;

    cyg_uint32 r30;

    cyg_uint32 r31;

#ifdef CYGHWR_HAL_POWERPC_FPU

    double     f14;

    double     f15;

    double     f16;

    double     f17;

    double     f18;

    double     f19;

    double     f20;

    double     f21;

    double     f22;

    double     f23;

    double     f24;

    double     f25;

    double     f26;

    double     f27;

    double     f28;

    double     f29;

    double     f30;

    double     f31;

#endif

    cyg_uint32 lr;

    cyg_uint32 cr;

} hal_jmp_buf_t;

#define CYGARC_JMP_BUF_SIZE      (sizeof(hal_jmp_buf_t) / sizeof(cyg_uint32))

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_)

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

// 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.

// Stack frame overhead per call. The PPC ABI defines regs 13..31 as callee

// saved. callee saved variables are irrelevant for us as they would contain

// automatic variables, so we only count the caller-saved regs here

// So that makes r0..r12 + cr, xer, lr, ctr:

#define CYGNUM_HAL_STACK_FRAME_SIZE (4 * 17)

// Stack needed for a context switch

#define CYGNUM_HAL_STACK_CONTEXT_SIZE \

    (38*4 /* offsetof(HAL_SavedRegisters, context_size) */)

// Interrupt + call to ISR, interrupt_end() and the DSR

#define CYGNUM_HAL_STACK_INTERRUPT_SIZE \

    ((43*4 /* sizeof(HAL_SavedRegisters) */) + 2 * CYGNUM_HAL_STACK_FRAME_SIZE)

// We have lots of registers so no particular amount is added in for

// typical local variable usage.

// We define a minimum stack size as the minimum any thread could ever

// legitimately get away with. We can throw asserts if users ask for less

// than this. Allow enough for three interrupt sources - clock, serial and

// one other

#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK 

// An interrupt stack which is large enough for all possible interrupt

// conditions (and only used for that purpose) exists.  "User" stacks

// can therefore be much smaller

# define CYGNUM_HAL_STACK_SIZE_MINIMUM \

         (16*CYGNUM_HAL_STACK_FRAME_SIZE + 2*CYGNUM_HAL_STACK_INTERRUPT_SIZE)

#else

// No separate interrupt stack exists.  Make sure all threads contain

// a stack sufficiently large

# define CYGNUM_HAL_STACK_SIZE_MINIMUM                  \

        (((2+3)*CYGNUM_HAL_STACK_INTERRUPT_SIZE) +      \

         (16*CYGNUM_HAL_STACK_FRAME_SIZE))

#endif

// Now make a reasonable choice for a typical thread size. Pluck figures

// from thin air and say 30 call frames with an average of 16 words of

// automatic variables per call frame

#define CYGNUM_HAL_STACK_SIZE_TYPICAL                \

        (CYGNUM_HAL_STACK_SIZE_MINIMUM +             \

         30 * (CYGNUM_HAL_STACK_FRAME_SIZE+(16*4)))

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

// Macros for switching context between two eCos instances (jump from

// code in ROM to code in RAM or vice versa).

// Should be defined like for MIPS, saving/restoring R2 - but is it

// actually used? I've never seen app code use R2. Something to investigate.

#define CYGARC_HAL_SAVE_GP()

#define CYGARC_HAL_RESTORE_GP()

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

#endif // CYGONCE_HAL_ARCH_H

// End of hal_arch.h