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#ifndef CYGONCE_KERNEL_SMP_HXX

#define CYGONCE_KERNEL_SMP_HXX

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

//

//      smp.hxx

//

//      SMP kernel support

//

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

// ####ECOSGPLCOPYRIGHTBEGIN####

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

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

// Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, 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.,

// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 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 v2.

//

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

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

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

// ####ECOSGPLCOPYRIGHTEND####

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

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

//

// Author(s):   nickg

// Contributors:nickg

// Date:        2001-02-10

// Purpose:     Kernel SMP support

// Description: If SMP support is configured into the kernel, then this file

//              translates HAL defined macros into C and C++ classes and methods

//              that can be called from the rest of the kernel. If SMP is not

//              configured in, then the same classes and methods are defined here

//              to operate correctly in a single CPU configuration.

//

// Usage:       #include 

//

//####DESCRIPTIONEND####

//

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

#include 

#include           // assertion macros

#include            // HAL_DISABLE_INTERRUPTS() etc.

#include 

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

#if defined(CYGPKG_KERNEL_SMP_SUPPORT) && (CYGPKG_HAL_SMP_SUPPORT)

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

// SMP support is included

#define CYG_KERNEL_SMP_ENABLED

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

// Get HAL support

#include 

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

// Defined values

// These all just map straight through to the HAL.

#define CYGNUM_KERNEL_CPU_MAX           HAL_SMP_CPU_MAX

#define CYG_KERNEL_CPU_COUNT()          HAL_SMP_CPU_COUNT()

#define CYG_KERNEL_CPU_THIS()           HAL_SMP_CPU_THIS()

#define CYG_KERNEL_CPU_NONE             HAL_SMP_CPU_NONE

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

// CPU control

#define CYG_KERNEL_CPU_START( __cpu ) HAL_SMP_CPU_START( __cpu )

#define CYG_KERNEL_CPU_RESCHEDULE_INTERRUPT( __cpu, __wait ) \

        HAL_SMP_CPU_RESCHEDULE_INTERRUPT( __cpu, __wait )

#define CYG_KERNEL_CPU_TIMESLICE_INTERRUPT( __cpu, __wait ) \

        HAL_SMP_CPU_TIMESLICE_INTERRUPT( __cpu, __wait )

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

// Scheduler lock default implementation.

// This implementation should serve for most targets. However, some

// targets may have hardware or other features that make simple

// spinlocks impossible, or allow us to implement the scheduler lock

// in a more efficient manner. If that is the case then the HAL will

// implement these macros itself.

#ifndef HAL_SMP_SCHEDLOCK_DATA_TYPE

#define HAL_SMP_SCHEDLOCK_DATA_TYPE struct hal_smp_schedlock_data_type

struct hal_smp_schedlock_data_type {

    HAL_SPINLOCK_TYPE           spinlock;

    volatile HAL_SMP_CPU_TYPE   holder;

};

#define HAL_SMP_SCHEDLOCK_INIT( __lock, __data )        \

CYG_MACRO_START                                         \

{                                                       \

    __lock = 1;                                         \

    HAL_SPINLOCK_CLEAR(__data.spinlock);                \

    HAL_SPINLOCK_SPIN(__data.spinlock);                 \

    __data.holder = HAL_SMP_CPU_THIS();                 \

}                                                       \

CYG_MACRO_END

#define HAL_SMP_SCHEDLOCK_INC( __lock, __data )                 \

CYG_MACRO_START                                                 \

{                                                               \

    CYG_INTERRUPT_STATE __state;                                \

    HAL_DISABLE_INTERRUPTS(__state);                            \

    if( __data.holder == HAL_SMP_CPU_THIS() )                   \

        __lock++;                                               \

    else                                                        \

    {                                                           \

        CYG_INSTRUMENT_SMP(LOCK_WAIT,CYG_KERNEL_CPU_THIS(),0);  \

        HAL_SPINLOCK_SPIN(__data.spinlock);                     \

        __data.holder = HAL_SMP_CPU_THIS();                     \

        __lock++;                                               \

        CYG_INSTRUMENT_SMP(LOCK_GOT,CYG_KERNEL_CPU_THIS(),0);   \

    }                                                           \

    HAL_RESTORE_INTERRUPTS(__state);                            \

}                                                               \

CYG_MACRO_END

#define HAL_SMP_SCHEDLOCK_ZERO( __lock, __data )                                                 \

CYG_MACRO_START                                                                                  \

{                                                                                                \

    CYG_INTERRUPT_STATE __state;                                                                 \

    HAL_DISABLE_INTERRUPTS(__state);                                                             \

    CYG_ASSERT( __data.holder == HAL_SMP_CPU_THIS(), "Zeroing schedlock not owned by me!");      \

    __lock = 0;                                                                                  \

    __data.holder = HAL_SMP_CPU_NONE;                                                            \

    HAL_SPINLOCK_CLEAR(__data.spinlock);                                                         \

    HAL_RESTORE_INTERRUPTS(__state);                                                             \

}                                                                                                \

CYG_MACRO_END

#define HAL_SMP_SCHEDLOCK_SET( __lock, __data, __new )                                          \

CYG_MACRO_START                                                                                 \

{                                                                                               \

    CYG_ASSERT( __data.holder == HAL_SMP_CPU_THIS(), "Setting schedlock not owned by me!");     \

    __lock = __new;                                                                             \

}                                                                                               \

CYG_MACRO_END

#endif

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

// SpinLock class

// This class supplies a C++ wrapper for the HAL spinlock API.

#ifdef __cplusplus

#ifdef HAL_SPINLOCK_SPIN

class Cyg_SpinLock

{

    HAL_SPINLOCK_TYPE   lock;

public:

    // Constructor, initialize the lock to clear

    Cyg_SpinLock() { lock = HAL_SPINLOCK_INIT_CLEAR; };

    ~Cyg_SpinLock()

    {

//        CYG_ASSERT( !test(), "spinlock still claimed");

    };

    // Spin on the lock.

    void spin()

    {

        HAL_SPINLOCK_SPIN(lock);

    };

    // Clear the lock.

    void clear()

    {

        HAL_SPINLOCK_CLEAR(lock);

    };

    // Try to claim the lock. Return true if successful, false if not.

    cyg_bool trylock()

    {

        cyg_bool testval;

        HAL_SPINLOCK_TRY(lock,testval);

        return testval;

    };

    // Test the current value of the lock

    cyg_bool test()

    {

        cyg_bool testval;

        HAL_SPINLOCK_TEST(lock, testval);

        return testval;

    };

    // The following two member functions are only necessary if the

    // spinlock is to be used in an ISR.

    // Claim the spinlock, but also mask this CPU's interrupts while

    // we have it.

    void spin_intsave(CYG_INTERRUPT_STATE *state)

    {

        CYG_INTERRUPT_STATE s;

        HAL_DISABLE_INTERRUPTS(s);

        *state = s;

        spin();

    };

    // Clear the lock, and restore the interrupt state saved in

    // spin_intsave().

    void clear_intsave(CYG_INTERRUPT_STATE state)

    {

        clear();

        HAL_RESTORE_INTERRUPTS(state);

    };

};

#endif

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

// Scheduler lock class

// This uses the scheduler lock API defined by the HAL, or the defaults

// defined above.

class Cyg_Scheduler_SchedLock

{

    static volatile cyg_ucount32 sched_lock         // lock counter

                    CYGBLD_ATTRIB_ASM_ALIAS( cyg_scheduler_sched_lock )

                    CYGBLD_ANNOTATE_VARIABLE_SCHED

                    ;

    static HAL_SMP_SCHEDLOCK_DATA_TYPE lock_data

                                       CYGBLD_ANNOTATE_VARIABLE_SCHED;

protected:

    Cyg_Scheduler_SchedLock()

    {

        HAL_SMP_SCHEDLOCK_INIT( sched_lock, lock_data );

    };

    // Increment the scheduler lock. If this takes the lock from zero

    // to one then this code must also do whatever is necessary to

    // serialize CPUs through the scheduler.

    static void inc_sched_lock()

    {

        CYG_INSTRUMENT_SMP(LOCK_INC,CYG_KERNEL_CPU_THIS(),0);

        HAL_SMP_SCHEDLOCK_INC( sched_lock, lock_data );

    };

    // Zero the scheduler lock. This will release the CPU serializing

    // lock and allow another CPU in.

    static void zero_sched_lock()

    {

        CYG_INSTRUMENT_SMP(LOCK_ZERO,CYG_KERNEL_CPU_THIS(),0);

        CYG_ASSERT( sched_lock != 0, "Scheduler lock already zero");

        HAL_SMP_SCHEDLOCK_ZERO( sched_lock, lock_data );

    };

    // Set the scheduler lock to a non-zero value. Both the scheduler

    // lock and the new value must be non-zero.

    static void set_sched_lock(cyg_uint32 new_lock)

    {

        CYG_INSTRUMENT_SMP(LOCK_SET,CYG_KERNEL_CPU_THIS(),new_lock);

        CYG_ASSERT( new_lock > 0, "New scheduler lock value == 0");

        CYG_ASSERT( sched_lock > 0, "Scheduler lock == 0");

        HAL_SMP_SCHEDLOCK_SET( sched_lock, lock_data, new_lock );

    };

    static cyg_ucount32 get_sched_lock()

    {

        return sched_lock;

    };

};

#define CYGIMP_KERNEL_SCHED_LOCK_DEFINITIONS                    \

volatile cyg_ucount32 Cyg_Scheduler_SchedLock::sched_lock = 1;  \

HAL_SMP_SCHEDLOCK_DATA_TYPE Cyg_Scheduler_SchedLock::lock_data;

#endif // __cplusplus

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

#else // defined(CYGSEM_KERNEL_SMP_SUPPORT) && (CYGSEM_HAL_SMP_SUPPORT)

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

// SMP support is NOT included.

#undef CYG_KERNEL_SMP_ENABLED

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

// Defined values

// Supply a set of values that describe a single CPU system.

#ifndef HAL_SMP_CPU_TYPE

#define HAL_SMP_CPU_TYPE                cyg_uint32

#endif

#define CYGNUM_KERNEL_CPU_MAX           1

#define CYG_KERNEL_CPU_COUNT()          1

#define CYG_KERNEL_CPU_THIS()           0

#define CYG_KERNEL_CPU_NONE             -1

#define CYG_KERNEL_CPU_LOWPRI()         CYG_KERNEL_CPU_THIS()

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

// SpinLock class

// This single CPU version simply goes through the motions of setting

// and clearing the lock variable for debugging purposes.

#ifdef __cplusplus

class Cyg_SpinLock

{

    volatile cyg_uint32 lock;

public:

    // Constructor, initialize the lock to clear

    Cyg_SpinLock() { lock = 0; };

    ~Cyg_SpinLock()

    {

        CYG_ASSERT( lock == 0, "spinlock still claimed");

    };

    // Spin on the lock. In this case we just set it to 1 and proceed.

    void spin()

    {

        CYG_ASSERT( lock == 0, "spinlock already claimed!");

        lock = 1;

    };

    // Clear the lock. Again, just set the value.

    void clear()

    {

        CYG_ASSERT( lock != 0, "spinlock already cleared!");

        lock = 0;

    };

    // Try to claim the lock. Return true if successful, false if not.

    cyg_bool trylock()

    {

        if( lock ) return false;

        else { lock = 1; return true; }

    };

    // Test the current value of the lock

    cyg_bool test() { return lock; };

    // The following two member functions are only necessary if the

    // spinlock is to be used in an ISR.

    // Claim the spinlock, but also mask this CPU's interrupts while

    // we have it.

    void spin_intsave(CYG_INTERRUPT_STATE *state)

    {

        CYG_INTERRUPT_STATE s;

        HAL_DISABLE_INTERRUPTS(s);

        *state = s;

        spin();

    };

    // Clear the lock, and restore the interrupt state saved in

    // spin_intsave().

    void clear_intsave(CYG_INTERRUPT_STATE state)

    {

        clear();

        HAL_RESTORE_INTERRUPTS(state);

    };

};

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

// Scheduler lock class

class Cyg_Scheduler_SchedLock

{

    static volatile cyg_ucount32 sched_lock         // lock counter

                    CYGBLD_ATTRIB_ASM_ALIAS( cyg_scheduler_sched_lock )

                    CYGBLD_ANNOTATE_VARIABLE_SCHED

                    ;

    // For non-SMP versions, the code here does the basic and obvious things.

protected:

    Cyg_Scheduler_SchedLock()

    {

        sched_lock = 1;

    };

    // Increment the scheduler lock, possibly taking it from zero to

    // one.

    static void inc_sched_lock()

    {

        sched_lock++;

    };

    static void zero_sched_lock()

    {

        CYG_ASSERT( sched_lock != 0, "Scheduler lock already zero");

        sched_lock = 0;

    };

    // Set the scheduler lock to a non-zero value. Both the scheduler

    // lock and the new value must be non-zero.

    static void set_sched_lock(cyg_uint32 new_lock)

    {

        CYG_ASSERT( new_lock > 0, "New scheduler lock value == 0");

        CYG_ASSERT( sched_lock > 0, "Scheduler lock == 0");

        sched_lock = new_lock;

    };

    static cyg_ucount32 get_sched_lock()

    {

        return sched_lock;

    };

};

#define CYGIMP_KERNEL_SCHED_LOCK_DEFINITIONS                    \

volatile cyg_ucount32 Cyg_Scheduler_SchedLock::sched_lock = 1;

#endif // __cplusplus

#endif // defined(CYGSEM_KERNEL_SMP_SUPPORT) && (CYGSEM_HAL_SMP_SUPPORT)

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

#endif // ifndef CYGONCE_KERNEL_SMP_HXX

// EOF smp.hxx