Modified start_gcc.s for mini2440

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@451 bbd45198-f89e-11dd-88c7-29a3b14d5316

libcpu/arm/s3c24x0/start_gcc.s

@@ -5,64 +5,97 @@
  *
  * The license and distribution terms for this file may be
  * found in the file LICENSE in this distribution or at
- * http://openlab.rt-thread.com/license/LICENSE
+ * http:/*openlab.rt-thread.com/license/LICENSE
  *
  * Change Logs:
  * Date           Author       Notes
  * 2006-03-13     Bernard      first version
- * 2006-10-05     Alsor.Z      for s3c2410 initialize
+ * 2006-10-05     Alsor.Z      for s3c2440 initialize
  * 2008-01-29     Yi.Qiu       for QEMU emulator
  */
 
-/**
- * @addtogroup S3C2410
+#define CONFIG_STACKSIZE 	512
+#define S_FRAME_SIZE 		72
+
+#define S_OLD_R0 			68
+#define S_PSR  				64
+#define S_PC  				60
+#define S_LR  				56
+#define S_SP  				52
+
+#define S_IP  				48
+#define S_FP  				44
+#define S_R10  				40
+#define S_R9  				36
+#define S_R8  				32
+#define S_R7  				28
+#define S_R6  				24
+#define S_R5  				20
+#define S_R4  				16
+#define S_R3  				12
+#define S_R2  				8
+#define S_R1  				4
+#define S_R0 				0
+
+.equ 	USERMODE, 			0x10
+.equ 	FIQMODE,			0x11
+.equ 	IRQMODE,			0x12
+.equ 	SVCMODE,			0x13
+.equ 	ABORTMODE,			0x17
+.equ 	UNDEFMODE,			0x1b
+.equ 	MODEMASK,			0x1f
+.equ 	NOINT,				0xc0
+
+.equ 	RAM_BASE,			0x00000000	/*Start address of RAM		*/
+.equ 	ROM_BASE,			0x30000000	/*Start address of Flash	*/
+
+.equ 	MPLLCON,			0x4c000004	/*Mpll control register		*/
+.equ 	M_MDIV,				0x20
+.equ 	M_PDIV,				0x4
+.equ 	M_SDIV,				0x2
+
+.equ 	INTMSK,				0x4a000008
+.equ 	INTSUBMSK, 			0x4a00001c
+.equ 	WTCON, 				0x53000000
+.equ 	LOCKTIME,			0x4c000000
+.equ 	CLKDIVN,			0x4c000014	/*Clock divider control		*/
+.equ 	GPHCON,				0x56000070	/*Port H control			*/
+.equ 	GPHUP,				0x56000078	/*Pull-up control H			*/
+.equ 	BWSCON,				0x48000000	/*Bus width & wait status	*/
+.equ 	BANKCON0,			0x48000004	/*Boot ROM control			*/
+.equ 	BANKCON1,			0x48000008	/*BANK1 control				*/
+.equ 	BANKCON2,			0x4800000c	/*BANK2 cControl			*/
+.equ 	BANKCON3,			0x48000010	/*BANK3 control				*/
+.equ 	BANKCON4,			0x48000014	/*BANK4 control				*/
+.equ 	BANKCON5,			0x48000018	/*BANK5 control				*/
+.equ 	BANKCON6,			0x4800001c	/*BANK6 control				*/
+.equ 	BANKCON7,			0x48000020	/*BANK7 control				*/
+.equ 	REFRESH,			0x48000024	/*DRAM/SDRAM efresh			*/
+.equ 	BANKSIZE,			0x48000028	/*Flexible Bank Size		*/
+.equ 	MRSRB6,				0x4800002c	/*Mode egister set for SDRAM*/
+.equ 	MRSRB7,				0x48000030	/*Mode egister set for SDRAM*/
+
+/*
+ *************************************************************************
+ *
+ * Jump vector table
+ *
+ *************************************************************************
  */
-/*@{*/
-
-#define CONFIG_STACKSIZE 512
-#define S_FRAME_SIZE 72
-
-#define S_OLD_R0 68
-#define S_PSR  64
-#define S_PC  60
-#define S_LR  56
-#define S_SP  52
-
-#define S_IP  48
-#define S_FP  44
-#define S_R10  40
-#define S_R9  36
-#define S_R8  32
-#define S_R7  28
-#define S_R6  24
-#define S_R5  20
-#define S_R4  16
-#define S_R3  12
-#define S_R2  8
-#define S_R1  4
-#define S_R0  0
-
-	.equ USERMODE, 	0x10
-	.equ FIQMODE,	0x11
-	.equ IRQMODE,	0x12
-	.equ SVCMODE,	0x13
-	.equ ABORTMODE,	0x17
-	.equ UNDEFMODE,	0x1b
-	.equ MODEMASK,	0x1f
-	.equ NOINT,		0xc0
 
 .section .init, "ax"
 .code 32
+
 .globl _start
 _start:
-	b	reset
-	ldr	pc, _vector_undef
-	ldr	pc, _vector_swi
-	ldr	pc, _vector_pabt
-	ldr	pc, _vector_dabt
-	ldr	pc, _vector_resv
-	ldr	pc, _vector_irq
-	ldr	pc, _vector_fiq
+	b		reset
+	ldr		pc, _vector_undef
+	ldr		pc, _vector_swi
+	ldr		pc, _vector_pabt
+	ldr		pc, _vector_dabt
+	ldr		pc, _vector_resv
+	ldr		pc, _vector_irq
+	ldr		pc, _vector_fiq
 
 _vector_undef:	.word vector_undef
 _vector_swi:	.word vector_swi
@@ -72,7 +105,18 @@ _vector_resv:	.word vector_resv
 _vector_irq:	.word vector_irq
 _vector_fiq:	.word vector_fiq
 
-	.balignl 16,0xdeadbeef
+.balignl 	16,0xdeadbeef
+
+/*
+ *************************************************************************
+ *
+ * Startup Code (reset vector)
+ * relocate armboot to ram
+ * setup stack
+ * jump to second stage
+ *
+ *************************************************************************
+ */
 
 _TEXT_BASE:
 	.word	TEXT_BASE
@@ -82,104 +126,95 @@ _TEXT_BASE:
  * which are defined in linker script
  */
 .globl _rtthread_start
-_rtthread_start:.word _start
+_rtthread_start:
+	.word _start
+	
 .globl _rtthread_end
-_rtthread_end:	.word  _end
+_rtthread_end:
+	.word  _end
 
 /*
- * rtthread bss start and end
- * which are defined in linker script
+ * rtthread bss start and end which are defined in linker script
  */
 .globl _bss_start
-_bss_start:	.word __bss_start
+_bss_start:	
+	.word __bss_start
+	
 .globl _bss_end
-_bss_end:	.word __bss_end
+_bss_end:
+	.word __bss_end
 
-/* IRQ stack memory (calculated at run-time) */
+/* IRQ stack memory (calculated at run-time) 						*/
 .globl IRQ_STACK_START
-IRQ_STACK_START:.word _irq_stack_start + 1024
+IRQ_STACK_START:
+	.word _irq_stack_start + 1024
+	
 .globl FIQ_STACK_START
-FIQ_STACK_START:.word _fiq_stack_start + 1024
+FIQ_STACK_START:
+	.word _fiq_stack_start + 1024
+	
 .globl UNDEFINED_STACK_START
-UNDEFINED_STACK_START:.word _undefined_stack_start + CONFIG_STACKSIZE
+UNDEFINED_STACK_START:
+	.word _undefined_stack_start + CONFIG_STACKSIZE
+	
 .globl ABORT_STACK_START
-ABORT_STACK_START:.word _abort_stack_start + CONFIG_STACKSIZE
+ABORT_STACK_START:
+	.word _abort_stack_start + CONFIG_STACKSIZE
+	
 .globl _STACK_START
-_STACK_START:.word _svc_stack_start + 4096
-
-	.equ RAM_BASE,	0x00000000	//Start address of RAM
-	.equ ROM_BASE,	0x30000000	//Start address of Flash
-
-	.equ INTMSK,	0x4a000008
-	.equ WTCON, 	0x53000000
-	.equ INTSUBMSK, 0x4a00001c
-	.equ LOCKTIME,	0x4c000000
-
-	.equ MPLLCON,	0x4c000004
-	.equ M_MDIV,	0x20
-	.equ M_PDIV,	0x4
-	.equ M_SDIV,	0x2
-	.equ CLKDIVN,	0x4c000014	//Clock divider control
-	.equ GPHCON,	0x56000070	//Port H control
-	.equ GPHUP,		0x56000078	//Pull-up control H
-	.equ BWSCON,	0x48000000	//Bus width & wait status
-	.equ BANKCON0,	0x48000004	//Boot ROM control
-	.equ BANKCON1,	0x48000008	//BANK1 control
-	.equ BANKCON2,	0x4800000c	//BANK2 cControl
-	.equ BANKCON3,	0x48000010	//BANK3 control
-	.equ BANKCON4,	0x48000014	//BANK4 control
-	.equ BANKCON5,	0x48000018	//BANK5 control
-	.equ BANKCON6,	0x4800001c	//BANK6 control
-	.equ BANKCON7,	0x48000020	//BANK7 control
-	.equ REFRESH,	0x48000024	//DRAM/SDRAM efresh
-	.equ BANKSIZE,	0x48000028	//Flexible Bank Size
-	.equ MRSRB6,	0x4800002c	//Mode egister set for SDRAM
-	.equ MRSRB7,	0x48000030	//Mode egister set for SDRAM
-
-/* -----------------entry--------------- */
+_STACK_START:
+	.word _svc_stack_start + 4096
+
+/* ----------------------------------entry------------------------------*/
 reset:
-	/* watch dog disable */
-	ldr r0,=WTCON
-	ldr r1,=0x0
-	str r1,[r0]
-
-	/* set the cpu to SVC32 mode */
-	mrs	r0,cpsr
-	bic	r0,r0,#MODEMASK
-	orr	r0,r0,#SVCMODE
-	msr	cpsr,r0
-
-	/* mask all IRQs by clearing all bits in the INTMRs */
-	ldr	r1, =INTMSK
-	ldr	r0, =0xffffffff
-	str	r0, [r1]
-
-	/* set interrupt vector 	*/
-	ldr r0, _load_address
-	mov	r1, #0x0				/* target address    		*/
-	add	r2, r0, #0x20			/* size, 32bytes         	*/
+	
+	/* set the cpu to SVC32 mode 	*/
+	mrs		r0,cpsr
+	bic		r0,r0,#MODEMASK
+	orr		r0,r0,#SVCMODE
+	msr		cpsr,r0
+	
+	/* watch dog disable 			*/
+	ldr 	r0,=WTCON
+	ldr 	r1,=0x0
+	str 	r1,[r0]
+
+	/* mask all IRQs by clearing all bits in the INTMRs 				*/
+	ldr		r1, =INTMSK
+	ldr		r0, =0xffffffff
+	str		r0, [r1]
+	ldr		r1, =INTSUBMSK
+	ldr		r0, =0x7fff				/*all sub interrupt disable			*/
+	str		r0, [r1]
+
+	/* set interrupt vector 		*/
+	ldr 	r0, _load_address
+	mov		r1, #0x0				/* target address    				*/
+	add		r2, r0, #0x20			/* size, 32bytes         			*/
 
 copy_loop:
-	ldmia	r0!, {r3-r10}		/* copy from source address [r0]    */
-	stmia	r1!, {r3-r10}		/* copy to   target address [r1]    */
-	cmp	r0, r2					/* until source end addreee [r2]    */
-	ble	copy_loop
+	ldmia	r0!, {r3-r10}			/* copy from source address [r0]    */
+	stmia	r1!, {r3-r10}			/* copy to   target address [r1]    */
+	cmp		r0, r2					/* until source end addreee [r2]    */
+	ble		copy_loop
 
 	/* setup stack */
-	bl	stack_setup
+	bl		stack_setup
 
 	/* clear .bss */
-	mov   r0,#0                     /* get a zero 				*/
-	ldr   r1,=__bss_start           /* bss start 				*/
-	ldr   r2,=__bss_end           	/* bss end 					*/
+	mov   	r0,#0                   /* get a zero 						*/
+	ldr   	r1,=__bss_start         /* bss start 						*/
+	ldr   	r2,=__bss_end           /* bss end 							*/
+	
 bss_loop:
-	cmp   r1,r2                     /* check if data to clear 	*/
-	strlo r0,[r1],#4                /* clear 4 bytes 			*/
-	blo   bss_loop                  /* loop until done 			*/
+	cmp   	r1,r2                   /* check if data to clear 			*/
+	strlo 	r0,[r1],#4              /* clear 4 bytes 					*/
+	blo   	bss_loop                /* loop until done 					*/
 
-	/* call C++ constructors of global objects */
+	/* call C++ constructors of global objects 							*/
 	ldr 	r0, =__ctors_start__
 	ldr 	r1, =__ctors_end__
+	
 ctor_loop:
 	cmp 	r0, r1
 	beq 	ctor_end
@@ -188,17 +223,21 @@ ctor_loop:
 	mov 	lr, pc
 	bx 		r2
 	ldmfd 	sp!, {r0-r1}
-	b	ctor_loop
+	b		ctor_loop
+	
 ctor_end:
 
-	/* start RT-Thread Kernel */
-	ldr	pc, _rtthread_startup
+	/* start RT-Thread Kernel 		*/
+	ldr		pc, _rtthread_startup
 
-_rtthread_startup: .word rtthread_startup
+_rtthread_startup: 
+	.word rtthread_startup
 #if defined (__FLASH_BUILD__)
-_load_address: .word ROM_BASE + _TEXT_BASE
+_load_address: 
+	.word ROM_BASE + _TEXT_BASE
 #else
-_load_address: .word RAM_BASE + _TEXT_BASE
+_load_address: 
+	.word RAM_BASE + _TEXT_BASE
 #endif
 
 /*
@@ -209,63 +248,63 @@ _load_address: .word RAM_BASE + _TEXT_BASE
  *************************************************************************
  */
 
-/* exception handlers */
+/* exception handlers 				*/
 	.align  5
 vector_undef:
-	sub sp, sp, #S_FRAME_SIZE
-	stmia sp, {r0 - r12}   @ Calling r0-r12
-	add	r8, sp, #S_PC
-	stmdb   r8, {sp, lr}^               @ Calling SP, LR
-	str	lr, [r8, #0]                    @ Save calling PC
-	mrs	r6, spsr
-	str	r6, [r8, #4]                    @ Save CPSR
-	str	r0, [r8, #8]                    @ Save OLD_R0
-	mov	r0, sp
-
-	bl	rt_hw_trap_udef
+	sub 	sp, sp, #S_FRAME_SIZE
+	stmia 	sp, {r0 - r12}   		/* Calling r0-r12					*/
+	add		r8, sp, #S_PC
+	stmdb   r8, {sp, lr}^           /* Calling SP, LR					*/
+	str		lr, [r8, #0]            /* Save calling PC					*/
+	mrs		r6, spsr
+	str		r6, [r8, #4]            /* Save CPSR						*/
+	str		r0, [r8, #8]            /* Save OLD_R0						*/
+	mov		r0, sp
+
+	bl		rt_hw_trap_udef
 
 	.align	5
 vector_swi:
-	bl 	rt_hw_trap_swi
+	bl 		rt_hw_trap_swi
 
 	.align	5
 vector_pabt:
-	bl 	rt_hw_trap_pabt
+	bl 		rt_hw_trap_pabt
 
 	.align	5
 vector_dabt:
-	sub sp, sp, #S_FRAME_SIZE
-	stmia sp, {r0 - r12}   @ Calling r0-r12
-	add	r8, sp, #S_PC
-	stmdb   r8, {sp, lr}^               @ Calling SP, LR
-	str	lr, [r8, #0]                    @ Save calling PC
-	mrs	r6, spsr
-	str	r6, [r8, #4]                    @ Save CPSR
-	str	r0, [r8, #8]                    @ Save OLD_R0
-	mov	r0, sp
-
-	bl 	rt_hw_trap_dabt
+	sub 	sp, sp, #S_FRAME_SIZE
+	stmia 	sp, {r0 - r12}   		/* Calling r0-r12					*/
+	add		r8, sp, #S_PC
+	stmdb   r8, {sp, lr}^           /* Calling SP, LR					*/
+	str		lr, [r8, #0]            /* Save calling PC					*/
+	mrs		r6, spsr
+	str		r6, [r8, #4]            /* Save CPSR						*/
+	str		r0, [r8, #8]            /* Save OLD_R0						*/
+	mov		r0, sp
+
+	bl 		rt_hw_trap_dabt
 
 	.align	5
 vector_resv:
-	bl 	rt_hw_trap_resv
+	bl 		rt_hw_trap_resv
 
-.globl rt_interrupt_enter
-.globl rt_interrupt_leave
-.globl rt_thread_switch_interrput_flag
-.globl rt_interrupt_from_thread
-.globl rt_interrupt_to_thread
+.globl 		rt_interrupt_enter
+.globl 		rt_interrupt_leave
+.globl 		rt_thread_switch_interrput_flag
+.globl 		rt_interrupt_from_thread
+.globl 		rt_interrupt_to_thread
 vector_irq:
 	stmfd	sp!, {r0-r12,lr}
-	bl	rt_interrupt_enter
-	bl	rt_hw_trap_irq
-	bl	rt_interrupt_leave
+	bl		rt_interrupt_enter
+	bl		rt_hw_trap_irq
+	bl		rt_interrupt_leave
 
 	/* if rt_thread_switch_interrput_flag set, jump to _interrupt_thread_switch and don't return */
-	ldr	r0, =rt_thread_switch_interrput_flag
-	ldr	r1, [r0]
-	cmp	r1, #1
-	beq	_interrupt_thread_switch
+	ldr		r0, =rt_thread_switch_interrput_flag
+	ldr		r1, [r0]
+	cmp		r1, #1
+	beq		_interrupt_thread_switch
 
 	ldmfd	sp!, {r0-r12,lr}
 	subs	pc, lr, #4
@@ -273,79 +312,79 @@ vector_irq:
 	.align	5
 vector_fiq:
 	stmfd	sp!,{r0-r7,lr}
-	bl 	rt_hw_trap_fiq
+	bl 		rt_hw_trap_fiq
 	ldmfd	sp!,{r0-r7,lr}
 	subs	pc,lr,#4
 
 _interrupt_thread_switch:
-	mov	r1,  #0				@ clear rt_thread_switch_interrput_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			@ disable interrupt
-	orr	r0,  r3, #NOINT
-	msr	spsr_c, r0
-
-	ldr	r0,  =.+8			@ switch to interrupted task's stack
+	mov		r1,  #0					/* clear rt_thread_switch_interrput_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				/* disable interrupt				*/
+	orr		r0,  r3, #NOINT
+	msr		spsr_c, r0
+
+	ldr		r0,  =.+8				/* switch to interrupted task's stack*/
 	movs	pc,  r0
 
-	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
+	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 psr
-	mrs	r4,  spsr
-	stmfd	sp!, {r4}		@ push old task's spsr
+	stmfd	sp!, {r0-r3}			/* push old task's r3-r0			*/
+	stmfd	sp!, {r5}				/* push old task's psr				*/
+	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		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
+	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!, {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
+	ldmfd	sp!, {r0-r12,lr,pc}		/* pop new task's r0-r12,lr & pc	*/
 
 stack_setup:
-	mrs	r0, cpsr
-	bic	r0, r0, #MODEMASK
-	orr	r1, r0, #UNDEFMODE|NOINT
-	msr	cpsr_cxsf, r1		@ undef mode
-	ldr	sp, UNDEFINED_STACK_START
+	mrs		r0, cpsr
+	bic		r0, r0, #MODEMASK
+	orr		r1, r0, #UNDEFMODE|NOINT
+	msr		cpsr_cxsf, r1			/* undef mode						*/
+	ldr		sp, UNDEFINED_STACK_START
 
-	orr	r1,r0,#ABORTMODE|NOINT
-	msr	cpsr_cxsf,r1		@ abort mode
-	ldr	sp, ABORT_STACK_START
+	orr		r1,r0,#ABORTMODE|NOINT
+	msr		cpsr_cxsf,r1			/* abort mode						*/
+	ldr		sp, ABORT_STACK_START
 
-	orr	r1,r0,#IRQMODE|NOINT
-	msr	cpsr_cxsf,r1		@ IRQ mode
-	ldr	sp, IRQ_STACK_START
+	orr		r1,r0,#IRQMODE|NOINT
+	msr		cpsr_cxsf,r1			/* IRQ mode							*/
+	ldr		sp, IRQ_STACK_START
 
-	orr	r1,r0,#FIQMODE|NOINT
-	msr	cpsr_cxsf,r1		@ FIQ mode
-	ldr	sp, FIQ_STACK_START
+	orr		r1,r0,#FIQMODE|NOINT
+	msr		cpsr_cxsf,r1			/* FIQ mode							*/
+	ldr		sp, FIQ_STACK_START
 
-	bic	r0,r0,#MODEMASK
-	orr	r1,r0,#SVCMODE|NOINT
-	msr	cpsr_cxsf,r1		@ SVC mode
+	bic		r0,r0,#MODEMASK
+	orr		r1,r0,#SVCMODE|NOINT
+	msr		cpsr_cxsf,r1			/* SVC mode							*/
 
-	ldr	sp, _STACK_START
+	ldr		sp, _STACK_START
 
 	/* USER mode is not initialized. */
 
-	mov	pc,lr				@ The LR register may be not valid for the mode changes.
+	mov		pc,lr					/* The LR register may be not valid for the mode changes.*/
 
-/*@}*/
+/*/*}*/