ENTER_SLEEP
;NOTE.
;1) rGSTATUS3 should have the return address after wake-up from SLEEP mode.

ldr r0,=REFRESH
ldr r1,[r0]  ;r1=rREFRESH
orr r1, r1, #BIT_SELFREFRESH
str r1, [r0]  ;Enable SDRAM self-refresh
;//Enable SDRAM self-refresh

mov r1,#16   ;Wait until self-refresh is issued,which may not be needed.
0
subs r1,r1,#1
bne %B0
;//Wait until self-refresh is issued,which may not be needed

ldr r1,=MISCCR  ;IO register
ldr r0,[r1]
orr r0,r0,#(7<<17)  ;Set SCLK0=1, SCLK1=1, SCKE=1.
str r0,[r1]

ldr r0,=CLKCON  ; Enter sleep mode
str r2,[r0]

b .   ;CPU will die here.
;//进入Sleep Mode，1）设置SDRAM为self-refresh
;//       2）设置MISCCR bit[17] 1:sclk0=sclk 0:sclk0=0
;//         bit[18] 1:sclk1=sclk 0:sclk1=0
;//         bit[19] 1:Self refresh retain enable
;//           0:Self refresh retain disable
;//           When 1, After wake-up from sleep, The self-refresh will be retained.

WAKEUP_SLEEP
;Release SCLKn after wake-up from the SLEEP mode.
ldr r1,=MISCCR
ldr r0,[r1]
bic r0,r0,#(7<<17)  ;SCLK0:0->SCLK, SCLK1:0->SCLK, SCKE:0->=SCKE.
str r0,[r1]
;//设置MISCCR

;Set memory control registers
  ;ldr r0,=SMRDATA
  adrl r0, SMRDATA
ldr r1,=BWSCON ;BWSCON Address ;//总线宽度和等待控制寄存器
add r2, r0, #52 ;End address of SMRDATA
0
ldr r3, [r0], #4 ;数据处理后R0自加4，[R0]->R3，R0+4->R0
str r3, [r1], #4
cmp r2, r0
bne %B0
;//设置所有的memory control register，他的初始地址为BWSCON，初始化
;//数据在以SMRDATA为起始的存储区

mov r1,#256
0
subs r1,r1,#1 ;1) wait until the SelfRefresh is released.
bne %B0
;//1) wait until the SelfRefresh is released.

ldr r1,=GSTATUS3  ;GSTATUS3 has the start address just after SLEEP wake-up
ldr r0,[r1]

mov pc,r0
;//跳出Sleep Mode，进入Sleep状态前的PC

;=================================================================================

;如上所说,这里采用HANDLER宏去建立Hander***和Handle***之间的联系
LTORG       ;声明文字池,因为我们用了ldr伪指令

HandlerFIQ      HANDLER HandleFIQ
HandlerIRQ      HANDLER HandleIRQ
HandlerUndef    HANDLER HandleUndef
HandlerSWI      HANDLER HandleSWI
HandlerDabort   HANDLER HandleDabort
HandlerPabort   HANDLER HandlePabort

;===================================================================================
;呵呵,来了来了.好戏来了,这一段程序就是用来进行第二次查表的过程了.
;如果说第一次查表是由硬件来完成的,那这一次查表就是由软件来实现的了.
;为什么要查两次表??
;没有办法,ARM把所有的中断都归纳成一个IRQ中断异常和一个FIRQ中断异常
;第一次查表主要是查出是什么异常,可我们总要知道是这个中断异常中的什么中断呀!
;没办法了,再查一次表呗!
;===================================================================================