500 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			500 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
;/*****************************************************************************/
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						|
;/* SAM7.S: Startup file for Atmel AT91SAM7 device series                     */
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;/*****************************************************************************/
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;/* <<< Use Configuration Wizard in Context Menu >>>                          */ 
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;/*****************************************************************************/
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;/* This file is part of the uVision/ARM development tools.                   */
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;/* Copyright (c) 2005-2006 Keil Software. All rights reserved.               */
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;/* This software may only be used under the terms of a valid, current,       */
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;/* end user licence from KEIL for a compatible version of KEIL software      */
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;/* development tools. Nothing else gives you the right to use this software. */
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;/*****************************************************************************/
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;/*
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; *  The SAM7.S code is executed after CPU Reset. This file may be 
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; *  translated with the following SET symbols. In uVision these SET 
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; *  symbols are entered under Options - ASM - Define.
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; *
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; *  REMAP: when set the startup code remaps exception vectors from
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; *  on-chip RAM to address 0.
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; *
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; *  RAM_INTVEC: when set the startup code copies exception vectors 
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; *  from on-chip Flash to on-chip RAM.
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; */
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; Standard definitions of Mode bits and Interrupt (I & F) flags in PSRs
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Mode_USR        EQU     0x10
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Mode_FIQ        EQU     0x11
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Mode_IRQ        EQU     0x12
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Mode_SVC        EQU     0x13
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Mode_ABT        EQU     0x17
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Mode_UND        EQU     0x1B
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Mode_SYS        EQU     0x1F
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I_Bit           EQU     0x80            ; when I bit is set, IRQ is disabled
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F_Bit           EQU     0x40            ; when F bit is set, FIQ is disabled
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; Internal Memory Base Addresses
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FLASH_BASE      EQU     0x00100000   
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RAM_BASE        EQU     0x00200000
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;// <h> Stack Configuration (Stack Sizes in Bytes)
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;//   <o0> Undefined Mode      <0x0-0xFFFFFFFF:8>
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;//   <o1> Supervisor Mode     <0x0-0xFFFFFFFF:8>
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;//   <o2> Abort Mode          <0x0-0xFFFFFFFF:8>
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;//   <o3> Fast Interrupt Mode <0x0-0xFFFFFFFF:8>
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;//   <o4> Interrupt Mode      <0x0-0xFFFFFFFF:8>
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;//   <o5> User/System Mode    <0x0-0xFFFFFFFF:8>
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;// </h>
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UND_Stack_Size  EQU     0x00000000
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SVC_Stack_Size  EQU     0x00000100
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ABT_Stack_Size  EQU     0x00000000
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FIQ_Stack_Size  EQU     0x00000000
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IRQ_Stack_Size  EQU     0x00000100
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USR_Stack_Size  EQU     0x00000100
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ISR_Stack_Size  EQU     (UND_Stack_Size + SVC_Stack_Size + ABT_Stack_Size + \
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                         FIQ_Stack_Size + IRQ_Stack_Size)
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                AREA    STACK, NOINIT, READWRITE, ALIGN=3
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Stack_Mem       SPACE   USR_Stack_Size
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__initial_sp    SPACE   ISR_Stack_Size
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Stack_Top
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;// <h> Heap Configuration
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;//   <o>  Heap Size (in Bytes) <0x0-0xFFFFFFFF>
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;// </h>
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Heap_Size       EQU     0x00000000
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                AREA    HEAP, NOINIT, READWRITE, ALIGN=3
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__heap_base
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Heap_Mem        SPACE   Heap_Size
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__heap_limit
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; Reset Controller (RSTC) definitions
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RSTC_BASE       EQU     0xFFFFFD00      ; RSTC Base Address
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RSTC_MR         EQU     0x08            ; RSTC_MR Offset
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;/*
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;// <e> Reset Controller (RSTC)
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;//   <o1.0>     URSTEN: User Reset Enable
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;//              <i> Enables NRST Pin to generate Reset
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;//   <o1.8..11> ERSTL: External Reset Length <0-15>
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;//              <i> External Reset Time in 2^(ERSTL+1) Slow Clock Cycles
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;// </e>
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;*/
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RSTC_SETUP      EQU     1
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RSTC_MR_Val     EQU     0xA5000401
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; Embedded Flash Controller (EFC) definitions
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EFC_BASE        EQU     0xFFFFFF00      ; EFC Base Address
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EFC0_FMR        EQU     0x60            ; EFC0_FMR Offset
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EFC1_FMR        EQU     0x70            ; EFC1_FMR Offset
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;// <e> Embedded Flash Controller 0 (EFC0)
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;//   <o1.16..23> FMCN: Flash Microsecond Cycle Number <0-255>
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;//               <i> Number of Master Clock Cycles in 1us
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;//   <o1.8..9>   FWS: Flash Wait State
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;//               <0=> Read: 1 cycle / Write: 2 cycles
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;//               <1=> Read: 2 cycle / Write: 3 cycles
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;//               <2=> Read: 3 cycle / Write: 4 cycles
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;//               <3=> Read: 4 cycle / Write: 4 cycles
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;// </e>
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EFC0_SETUP      EQU     1
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EFC0_FMR_Val    EQU     0x00320100
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;// <e> Embedded Flash Controller 1 (EFC1)
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;//   <o1.16..23> FMCN: Flash Microsecond Cycle Number <0-255>
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;//               <i> Number of Master Clock Cycles in 1us
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;//   <o1.8..9>   FWS: Flash Wait State
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;//               <0=> Read: 1 cycle / Write: 2 cycles
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;//               <1=> Read: 2 cycle / Write: 3 cycles
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;//               <2=> Read: 3 cycle / Write: 4 cycles
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;//               <3=> Read: 4 cycle / Write: 4 cycles
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;// </e>
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EFC1_SETUP      EQU     0
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EFC1_FMR_Val    EQU     0x00320100
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; Watchdog Timer (WDT) definitions
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WDT_BASE        EQU     0xFFFFFD40      ; WDT Base Address
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WDT_MR          EQU     0x04            ; WDT_MR Offset
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;// <e> Watchdog Timer (WDT)
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;//   <o1.0..11>  WDV: Watchdog Counter Value <0-4095>
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;//   <o1.16..27> WDD: Watchdog Delta Value <0-4095>
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;//   <o1.12>     WDFIEN: Watchdog Fault Interrupt Enable
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;//   <o1.13>     WDRSTEN: Watchdog Reset Enable
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;//   <o1.14>     WDRPROC: Watchdog Reset Processor
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;//   <o1.28>     WDDBGHLT: Watchdog Debug Halt
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;//   <o1.29>     WDIDLEHLT: Watchdog Idle Halt
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;//   <o1.15>     WDDIS: Watchdog Disable
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;// </e>
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WDT_SETUP       EQU     1
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WDT_MR_Val      EQU     0x00008000
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; Power Mangement Controller (PMC) definitions
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PMC_BASE        EQU     0xFFFFFC00      ; PMC Base Address
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PMC_MOR         EQU     0x20            ; PMC_MOR Offset
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PMC_MCFR        EQU     0x24            ; PMC_MCFR Offset
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PMC_PLLR        EQU     0x2C            ; PMC_PLLR Offset
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PMC_MCKR        EQU     0x30            ; PMC_MCKR Offset
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PMC_SR          EQU     0x68            ; PMC_SR Offset
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PMC_MOSCEN      EQU     (1<<0)          ; Main Oscillator Enable
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PMC_OSCBYPASS   EQU     (1<<1)          ; Main Oscillator Bypass
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PMC_OSCOUNT     EQU     (0xFF<<8)       ; Main OScillator Start-up Time
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PMC_DIV         EQU     (0xFF<<0)       ; PLL Divider
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PMC_PLLCOUNT    EQU     (0x3F<<8)       ; PLL Lock Counter
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PMC_OUT         EQU     (0x03<<14)      ; PLL Clock Frequency Range
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PMC_MUL         EQU     (0x7FF<<16)     ; PLL Multiplier
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PMC_USBDIV      EQU     (0x03<<28)      ; USB Clock Divider
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PMC_CSS         EQU     (3<<0)          ; Clock Source Selection
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PMC_PRES        EQU     (7<<2)          ; Prescaler Selection
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PMC_MOSCS       EQU     (1<<0)          ; Main Oscillator Stable
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PMC_LOCK        EQU     (1<<2)          ; PLL Lock Status
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PMC_MCKRDY      EQU     (1<<3)          ; Master Clock Status
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;// <e> Power Mangement Controller (PMC)
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;//   <h> Main Oscillator
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;//     <o1.0>      MOSCEN: Main Oscillator Enable
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;//     <o1.1>      OSCBYPASS: Oscillator Bypass
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;//     <o1.8..15>  OSCCOUNT: Main Oscillator Startup Time <0-255>
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;//   </h>
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;//   <h> Phase Locked Loop (PLL)
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;//     <o2.0..7>   DIV: PLL Divider <0-255>
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;//     <o2.16..26> MUL: PLL Multiplier <0-2047>
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;//                 <i> PLL Output is multiplied by MUL+1
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;//     <o2.14..15> OUT: PLL Clock Frequency Range
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;//                 <0=> 80..160MHz  <1=> Reserved
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;//                 <2=> 150..220MHz <3=> Reserved
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;//     <o2.8..13>  PLLCOUNT: PLL Lock Counter <0-63>
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;//     <o2.28..29> USBDIV: USB Clock Divider
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;//                 <0=> None  <1=> 2  <2=> 4  <3=> Reserved
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;//   </h>
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;//   <o3.0..1>   CSS: Clock Source Selection
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;//               <0=> Slow Clock
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;//               <1=> Main Clock
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;//               <2=> Reserved
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;//               <3=> PLL Clock
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;//   <o3.2..4>   PRES: Prescaler
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;//               <0=> None
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;//               <1=> Clock / 2    <2=> Clock / 4
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;//               <3=> Clock / 8    <4=> Clock / 16
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;//               <5=> Clock / 32   <6=> Clock / 64
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;//               <7=> Reserved
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;// </e>
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PMC_SETUP       EQU     1
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PMC_MOR_Val     EQU     0x00000601
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PMC_PLLR_Val    EQU     0x00191C05
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PMC_MCKR_Val    EQU     0x00000007
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                PRESERVE8
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; Area Definition and Entry Point
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;  Startup Code must be linked first at Address at which it expects to run.
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                AREA    RESET, CODE, READONLY
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                ARM
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; Exception Vectors
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;  Mapped to Address 0.
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;  Absolute addressing mode must be used.
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;  Dummy Handlers are implemented as infinite loops which can be modified.
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Vectors         LDR     PC,Reset_Addr         
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                LDR     PC,Undef_Addr
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                LDR     PC,SWI_Addr
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                LDR     PC,PAbt_Addr
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                LDR     PC,DAbt_Addr
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                NOP                            ; Reserved Vector
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                LDR     PC,IRQ_Addr
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                LDR     PC,FIQ_Addr
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Reset_Addr      DCD     Reset_Handler
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Undef_Addr      DCD     Undef_Handler
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SWI_Addr        DCD     SWI_Handler
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PAbt_Addr       DCD     PAbt_Handler
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DAbt_Addr       DCD     DAbt_Handler
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                DCD     0                      ; Reserved Address
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IRQ_Addr        DCD     IRQ_Handler
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FIQ_Addr        DCD     FIQ_Handler
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Undef_Handler   B       Undef_Handler
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SWI_Handler     B       SWI_Handler
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PAbt_Handler    B       PAbt_Handler
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DAbt_Handler    B       DAbt_Handler
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FIQ_Handler     B       FIQ_Handler
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; Reset Handler
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                EXPORT  Reset_Handler
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Reset_Handler   
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; Setup RSTC
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                IF      RSTC_SETUP != 0
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                LDR     R0, =RSTC_BASE
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                LDR     R1, =RSTC_MR_Val
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                STR     R1, [R0, #RSTC_MR]
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                ENDIF
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; Setup EFC0
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                IF      EFC0_SETUP != 0
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                LDR     R0, =EFC_BASE
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                LDR     R1, =EFC0_FMR_Val
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                STR     R1, [R0, #EFC0_FMR]
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                ENDIF
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; Setup EFC1
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                IF      EFC1_SETUP != 0
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                LDR     R0, =EFC_BASE
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                LDR     R1, =EFC1_FMR_Val
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                STR     R1, [R0, #EFC1_FMR]
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                ENDIF
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; Setup WDT
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                IF      WDT_SETUP != 0
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                LDR     R0, =WDT_BASE
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                LDR     R1, =WDT_MR_Val
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                STR     R1, [R0, #WDT_MR]
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                ENDIF
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; Setup PMC
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                IF      PMC_SETUP != 0
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                LDR     R0, =PMC_BASE
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;  Setup Main Oscillator
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                LDR     R1, =PMC_MOR_Val
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                STR     R1, [R0, #PMC_MOR]
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;  Wait until Main Oscillator is stablilized
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                IF      (PMC_MOR_Val:AND:PMC_MOSCEN) != 0
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MOSCS_Loop      LDR     R2, [R0, #PMC_SR]
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                ANDS    R2, R2, #PMC_MOSCS
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                BEQ     MOSCS_Loop
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                ENDIF
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;  Setup the PLL
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                IF      (PMC_PLLR_Val:AND:PMC_MUL) != 0
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                LDR     R1, =PMC_PLLR_Val
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                STR     R1, [R0, #PMC_PLLR]
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;  Wait until PLL is stabilized
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PLL_Loop        LDR     R2, [R0, #PMC_SR]
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                ANDS    R2, R2, #PMC_LOCK
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                BEQ     PLL_Loop
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                ENDIF
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;  Select Clock
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                IF      (PMC_MCKR_Val:AND:PMC_CSS) == 1     ; Main Clock Selected
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                LDR     R1, =PMC_MCKR_Val
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                AND     R1, #PMC_CSS
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                STR     R1, [R0, #PMC_MCKR]
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WAIT_Rdy1       LDR     R2, [R0, #PMC_SR]
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                ANDS    R2, R2, #PMC_MCKRDY
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                BEQ     WAIT_Rdy1
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                LDR     R1, =PMC_MCKR_Val
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                STR     R1, [R0, #PMC_MCKR]
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WAIT_Rdy2       LDR     R2, [R0, #PMC_SR]
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                ANDS    R2, R2, #PMC_MCKRDY
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                BEQ     WAIT_Rdy2
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                ELIF    (PMC_MCKR_Val:AND:PMC_CSS) == 3     ; PLL  Clock Selected
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                LDR     R1, =PMC_MCKR_Val
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                AND     R1, #PMC_PRES
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                STR     R1, [R0, #PMC_MCKR]
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WAIT_Rdy1       LDR     R2, [R0, #PMC_SR]
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                ANDS    R2, R2, #PMC_MCKRDY
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                BEQ     WAIT_Rdy1
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                LDR     R1, =PMC_MCKR_Val
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                STR     R1, [R0, #PMC_MCKR]
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WAIT_Rdy2       LDR     R2, [R0, #PMC_SR]
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                ANDS    R2, R2, #PMC_MCKRDY
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                BEQ     WAIT_Rdy2
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                ENDIF   ; Select Clock
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                ENDIF   ; PMC_SETUP
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; Copy Exception Vectors to Internal RAM
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                IF      :DEF:RAM_INTVEC
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                ADR     R8, Vectors         ; Source
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                LDR     R9, =RAM_BASE       ; Destination
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                LDMIA   R8!, {R0-R7}        ; Load Vectors 
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                STMIA   R9!, {R0-R7}        ; Store Vectors 
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                LDMIA   R8!, {R0-R7}        ; Load Handler Addresses 
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                STMIA   R9!, {R0-R7}        ; Store Handler Addresses
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                ENDIF
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; Remap on-chip RAM to address 0
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MC_BASE EQU     0xFFFFFF00      ; MC Base Address
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MC_RCR  EQU     0x00            ; MC_RCR Offset
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                IF      :DEF:REMAP
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                LDR     R0, =MC_BASE
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                MOV     R1, #1
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                STR     R1, [R0, #MC_RCR]   ; Remap
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                ENDIF
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; Setup Stack for each mode
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						|
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                LDR     R0, =Stack_Top
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;  Enter Undefined Instruction Mode and set its Stack Pointer
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						|
                MSR     CPSR_c, #Mode_UND:OR:I_Bit:OR:F_Bit
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						|
                MOV     SP, R0
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                SUB     R0, R0, #UND_Stack_Size
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						|
;  Enter Abort Mode and set its Stack Pointer
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                MSR     CPSR_c, #Mode_ABT:OR:I_Bit:OR:F_Bit
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                MOV     SP, R0
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                SUB     R0, R0, #ABT_Stack_Size
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;  Enter FIQ Mode and set its Stack Pointer
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                MSR     CPSR_c, #Mode_FIQ:OR:I_Bit:OR:F_Bit
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                MOV     SP, R0
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                SUB     R0, R0, #FIQ_Stack_Size
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;  Enter IRQ Mode and set its Stack Pointer
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						|
                MSR     CPSR_c, #Mode_IRQ:OR:I_Bit:OR:F_Bit
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						|
                MOV     SP, R0
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						|
                SUB     R0, R0, #IRQ_Stack_Size
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						|
 | 
						|
;  Enter Supervisor Mode and set its Stack Pointer
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						|
                MSR     CPSR_c, #Mode_SVC:OR:I_Bit:OR:F_Bit
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						|
                MOV     SP, R0
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						|
                SUB     R0, R0, #SVC_Stack_Size
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						|
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						|
;  Enter User Mode and set its Stack Pointer
 | 
						|
                ; MSR     CPSR_c, #Mode_USR
 | 
						|
                IF      :DEF:__MICROLIB
 | 
						|
 | 
						|
                EXPORT __initial_sp
 | 
						|
 | 
						|
                ELSE
 | 
						|
 | 
						|
                ; No usr mode stack here.
 | 
						|
                ;MOV     SP, R0
 | 
						|
                ;SUB     SL, SP, #USR_Stack_Size
 | 
						|
 | 
						|
                ENDIF
 | 
						|
 | 
						|
 | 
						|
; Enter the C code
 | 
						|
 | 
						|
                IMPORT  __main
 | 
						|
                LDR     R0, =__main
 | 
						|
                BX      R0
 | 
						|
 | 
						|
				IMPORT rt_interrupt_enter
 | 
						|
				IMPORT rt_interrupt_leave
 | 
						|
				IMPORT rt_thread_switch_interrupt_flag
 | 
						|
				IMPORT rt_interrupt_from_thread
 | 
						|
				IMPORT rt_interrupt_to_thread
 | 
						|
				IMPORT rt_hw_trap_irq
 | 
						|
 | 
						|
IRQ_Handler		PROC
 | 
						|
				EXPORT IRQ_Handler
 | 
						|
				STMFD	sp!, {r0-r12,lr}
 | 
						|
				BL	rt_interrupt_enter
 | 
						|
				BL	rt_hw_trap_irq
 | 
						|
				BL	rt_interrupt_leave
 | 
						|
 | 
						|
				; if rt_thread_switch_interrupt_flag set, jump to
 | 
						|
				; rt_hw_context_switch_interrupt_do and don't return
 | 
						|
				LDR	r0, =rt_thread_switch_interrupt_flag
 | 
						|
				LDR	r1, [r0]
 | 
						|
				CMP	r1, #1
 | 
						|
				BEQ	rt_hw_context_switch_interrupt_do
 | 
						|
 | 
						|
				LDMFD	sp!, {r0-r12,lr}
 | 
						|
				SUBS	pc, lr, #4
 | 
						|
				ENDP
 | 
						|
 | 
						|
; /*
 | 
						|
; * void rt_hw_context_switch_interrupt_do(rt_base_t flag)
 | 
						|
; */
 | 
						|
rt_hw_context_switch_interrupt_do	PROC
 | 
						|
				EXPORT rt_hw_context_switch_interrupt_do
 | 
						|
				MOV		r1,  #0			; clear flag
 | 
						|
				STR		r1,  [r0]
 | 
						|
 | 
						|
				LDMFD	sp!, {r0-r12,lr}; reload saved registers
 | 
						|
				STMFD	sp!, {r0-r3}	; save r0-r3
 | 
						|
				MOV		r1,  sp
 | 
						|
				ADD		sp,  sp, #16	; restore sp
 | 
						|
				SUB		r2,  lr, #4		; save old task's pc to r2
 | 
						|
 | 
						|
				MRS		r3,  spsr		; get cpsr of interrupt thread
 | 
						|
 | 
						|
				; switch to SVC mode and no interrupt
 | 
						|
                MSR     cpsr_c, #I_Bit|F_Bit|Mode_SVC
 | 
						|
 | 
						|
				STMFD	sp!, {r2}		; push old task's pc
 | 
						|
				STMFD	sp!, {r4-r12,lr}; push old task's lr,r12-r4
 | 
						|
				MOV		r4,  r1			; Special optimised code below
 | 
						|
				MOV		r5,  r3
 | 
						|
				LDMFD	r4!, {r0-r3}
 | 
						|
				STMFD	sp!, {r0-r3}	; push old task's r3-r0
 | 
						|
				STMFD	sp!, {r5}		; push old task's cpsr
 | 
						|
				MRS		r4,  spsr
 | 
						|
				STMFD	sp!, {r4}		; push old task's spsr
 | 
						|
 | 
						|
				LDR		r4,  =rt_interrupt_from_thread
 | 
						|
				LDR		r5,  [r4]
 | 
						|
				STR		sp,  [r5]		; store sp in preempted tasks's TCB
 | 
						|
 | 
						|
				LDR		r6,  =rt_interrupt_to_thread
 | 
						|
				LDR		r6,  [r6]
 | 
						|
				LDR		sp,  [r6]		; get new task's stack pointer
 | 
						|
			
 | 
						|
				LDMFD	sp!, {r4}		; pop new task's spsr
 | 
						|
				MSR		spsr_cxsf, r4
 | 
						|
				LDMFD	sp!, {r4}		; pop new task's psr
 | 
						|
				MSR		cpsr_cxsf, r4
 | 
						|
 | 
						|
				LDMFD	sp!, {r0-r12,lr,pc}	; pop new task's r0-r12,lr & pc
 | 
						|
				ENDP
 | 
						|
 | 
						|
                IF      :DEF:__MICROLIB
 | 
						|
 | 
						|
                EXPORT  __heap_base
 | 
						|
                EXPORT  __heap_limit
 | 
						|
 | 
						|
                ELSE
 | 
						|
; User Initial Stack & Heap
 | 
						|
                AREA    |.text|, CODE, READONLY
 | 
						|
 | 
						|
                IMPORT  __use_two_region_memory
 | 
						|
                EXPORT  __user_initial_stackheap
 | 
						|
__user_initial_stackheap
 | 
						|
 | 
						|
                LDR     R0, =  Heap_Mem
 | 
						|
                LDR     R1, = (Stack_Mem + IRQ_Stack_Size)
 | 
						|
                LDR     R2, = (Heap_Mem +      Heap_Size)
 | 
						|
                LDR     R3, = Stack_Mem
 | 
						|
                BX      LR
 | 
						|
                ENDIF
 | 
						|
 | 
						|
                END
 |