cpu_a.asm

ucosii和ucgui移植到LPC1788上

;********************************************************************************************************
;                                               uC/CPU
;                                    CPU CONFIGURATION & PORT LAYER
;
;                          (c) Copyright 2004-2008; Micrium, Inc.; Weston, FL
;
;               All rights reserved.  Protected by international copyright laws.
;
;               uC/CPU is provided in source form for FREE evaluation, for educational
;               use or peaceful research.  If you plan on using uC/CPU in a commercial
;               product you need to contact Micrium to properly license its use in your
;               product.  We provide ALL the source code for your convenience and to
;               help you experience uC/CPU.  The fact that the source code is provided
;               does NOT mean that you can use it without paying a licensing fee.
;
;               Knowledge of the source code may NOT be used to develop a similar product.
;
;               Please help us continue to provide the Embedded community with the finest
;               software available.  Your honesty is greatly appreciated.
;********************************************************************************************************


;********************************************************************************************************
;
;                                            CPU PORT FILE
;
;                                            ARM-Cortex-M3
;                                      RealView Development Suite
;                            RealView Microcontroller Development Kit (MDK)
;                                       ARM Developer Suite (ADS)
;                                            Keil uVision
;
; Filename      : cpu_a.asm
; Version       : V1.19
; Programmer(s) : BAN
;********************************************************************************************************


;********************************************************************************************************
;                                           PUBLIC FUNCTIONS
;********************************************************************************************************

        EXPORT  CPU_IntDis
        EXPORT  CPU_IntEn

        EXPORT  CPU_SR_Save
        EXPORT  CPU_SR_Restore
        
        EXPORT  CPU_CntLeadZeros
        EXPORT  CPU_RevBits

        EXPORT  CPU_WaitForInt
        EXPORT  CPU_WaitForExcept


;********************************************************************************************************
;                                      CODE GENERATION DIRECTIVES
;********************************************************************************************************

        AREA |.text|, CODE, READONLY, ALIGN=2
        THUMB
        REQUIRE8
        PRESERVE8


;$PAGE
;*********************************************************************************************************
;                                    DISABLE and ENABLE INTERRUPTS
;
; Description : Disable/Enable interrupts.
;
; Prototypes  : void  CPU_IntDis(void);
;               void  CPU_IntEn (void);
;*********************************************************************************************************

CPU_IntDis
        CPSID   I
        BX      LR


CPU_IntEn
        CPSIE   I
        BX      LR


;*********************************************************************************************************
;                                      CRITICAL SECTION FUNCTIONS
;
; Description : Disable/Enable interrupts by preserving the state of interrupts.  Generally speaking, the
;               state of the interrupt disable flag is stored in the local variable 'cpu_sr' & interrupts
;               are then disabled ('cpu_sr' is allocated in all functions that need to disable interrupts).
;               The previous interrupt state is restored by copying 'cpu_sr' into the CPU's status register.
;
; Prototypes  : CPU_SR  CPU_SR_Save   (void);
;               void    CPU_SR_Restore(CPU_SR cpu_sr);
;
;
; Note(s)     : (1) These functions are used in general like this:
;
;                   void  Task (void *p_arg)
;                   {
;                                                               /* Allocate storage for CPU status register */
;                   #if (CPU_CFG_CRITICAL_METHOD == CPU_CRITICAL_METHOD_STATUS_LOCAL)
;                       CPU_SR  cpu_sr;
;                   #endif
;
;                            :
;                            :
;                       CPU_CRITICAL_ENTER();                   /* cpu_sr = CPU_SR_Save();                  */
;                            :
;                            :
;                       CPU_CRITICAL_EXIT();                    /* CPU_SR_Restore(cpu_sr);                  */
;                            :
;                            :
;                   }
;*********************************************************************************************************

CPU_SR_Save
        MRS     R0, PRIMASK                     ; Set prio int mask to mask all (except faults)
        CPSID   I
        BX      LR


CPU_SR_Restore                                  ; See Note #2.
        MSR     PRIMASK, R0
        BX      LR


;$PAGE
;********************************************************************************************************
;                                         COUNT LEADING ZEROS
;
; Description : Counts the number of binary zero bits before the first binary one bit in the argument.
;               If the argument is zero, the value 32 is returned.
;
; Prototypes : CPU_INT32U  CPU_CntLeadZeros (CPU_INT32U  val)
;
; Argument(s) : val     variable to count leading zeros
;********************************************************************************************************

CPU_CntLeadZeros
        CLZ     R0, R0                          ; Count leading zeros
        BX      LR


;********************************************************************************************************
;                                             REVERSE BITS
;
; Description : Reverses the bits in the argument.
;
; Prototypes : CPU_INT32U  CPU_RevBits (CPU_INT32U  val)
;
; Argument(s) : val     variable to reverse
;********************************************************************************************************

CPU_RevBits
        RBIT    R0, R0                          ; Reverse bits
        BX      LR


;$PAGE
;********************************************************************************************************
;                                         WAIT FOR INTERRUPT
;
; Description : Enters sleep state, which will be exited when an interrupt is received.
;
; Prototypes  : void  CPU_WaitForInt (void)
;
; Argument(s) : none.
;********************************************************************************************************

CPU_WaitForInt
        WFI                                     ; Wait for interrupt
        BX      LR


;********************************************************************************************************
;                                         WAIT FOR EXCEPTION
;
; Description : Enters sleep state, which will be exited when an exception is received.
;
; Prototypes  : void  CPU_WaitForExcept (void)
;
; Argument(s) : none.
;********************************************************************************************************

CPU_WaitForExcept
        WFE                                     ; Wait for exception
        BX      LR


;$PAGE
;********************************************************************************************************
;                                     CPU ASSEMBLY PORT FILE END
;********************************************************************************************************

        END