os_cpu.h

没有开发板也可以学ARM。ucos-ii与ZLG-GUI的GBA移植

/*
*********************************************************************************************************
*                                               uC/OS-II
*                                         The Real-Time Kernel
*
*                                        Specific code for V2.8x
*
* File     : OS_CPU.H
* By       : 焦进星
* Date     : 2008年月1月26日 
*********************************************************************************************************
*/
#ifndef _OS_CPU_H_
#define _OS_CPU_H_


#define  OS_CRITICAL_METHOD    3

#ifndef OS_CPU_A	/* skip the rest if we're including from the assembler file */

#ifdef  OS_CPU_GLOBALS
#define OS_CPU_EXT
#else
#define OS_CPU_EXT  extern
#endif

/*
**********************************************************************************************************
*                                              DATA TYPES
*                                         (Compiler Specific)
**********************************************************************************************************
*/

typedef unsigned char     BOOLEAN;
typedef unsigned char     INT8U;                 /* Unsigned  8 bit quantity                            */
typedef signed   char     INT8S;                 /* Signed    8 bit quantity                            */
typedef unsigned short    INT16U;                /* Unsigned 16 bit quantity                            */
typedef signed   short    INT16S;                /* Signed   16 bit quantity                            */
typedef unsigned int      INT32U;                /* Unsigned 32 bit quantity                            */
typedef signed   int      INT32S;                /* Signed   32 bit quantity                            */
typedef float             FP32;                  /* Single precision floating point                     */

typedef unsigned int   OS_STK;                   /* Each stack entry is 32-bit wide                      */
typedef unsigned int   OS_CPU_SR;                /* Define size of SREG register (SREG = 32 bits)        */

/* 
*********************************************************************************************************
*                                            
*
* Method #1:  Disable/Enable interrupts using simple instructions.  After critical section, interrupts
*             will be enabled even if they were disabled before entering the critical section.
*
* Method #2:  Disable/Enable interrupts by preserving the state of interrupts. In other words, if
*             interrupts were disabled before entering the critical section, they will be disabled when
*             leaving the critical section.
*
* Method #3:  Disable/Enable interrupts by preserving the state of interrupts.  Generally speaking you
*             would store the state of the interrupt disable flag in the local variable 'cpu_sr' and then
*             disable interrupts.  'cpu_sr' is allocated in all of uC/OS-II's functions that need to 
*             disable interrupts.  You would restore the interrupt disable state by copying back 'cpu_sr'
*             into the CPU's status register.
*********************************************************************************************************
*/

#if      OS_CRITICAL_METHOD == 1
#define  OS_ENTER_CRITICAL() 
#define  OS_EXIT_CRITICAL()   
#endif

#if      OS_CRITICAL_METHOD == 2
#define  OS_ENTER_CRITICAL()  
#define  OS_EXIT_CRITICAL()   
#endif

#if      OS_CRITICAL_METHOD == 3
#define  OS_ENTER_CRITICAL()  (cpu_sr = OS_CPU_SR_Save()) /* Disable interrupts                        */
#define  OS_EXIT_CRITICAL()   (OS_CPU_SR_Restore(cpu_sr)) /* Enable  interrupts                        */
#endif

/*
**********************************************************************************************************
*                                          ARM Miscellaneous
**********************************************************************************************************
*/

#define  OSIntCtxSw()       ;						/* 不做任何操作                                    */

#define  OS_STK_GROWTH      1                       /* Stack grows from HIGH to LOW memory on ARM      */

#define  OS_TASK_SW()       OSCtxSw()

/*
**********************************************************************************************************
*                                          GLOBAL VARIABLES
**********************************************************************************************************
*/	

/*
**********************************************************************************************************
*                                         Function Prototypes
**********************************************************************************************************
*/

#if OS_CRITICAL_METHOD == 3
OS_CPU_SR  OS_CPU_SR_Save(void);
void       OS_CPU_SR_Restore(OS_CPU_SR cpu_sr);
#endif
void       OSStartHighRdy(void);
void       OSCtxSw(void);

#endif
#endif /*_OS_CPU_H_*/