在2440中進入休眠函數
void OEMPowerOff()
{
static UINT32 saveArea[51];
S3C2440A_INTR_REG *pIntr = (S3C2440A_INTR_REG*)OALPAtoVA(S3C2440A_BASE_REG_PA_INTR, FALSE);
S3C2440A_IOPORT_REG *pIOPort = (S3C2440A_IOPORT_REG*)OALPAtoVA(S3C2440A_BASE_REG_PA_IOPORT, FALSE);
S3C2440A_LCD_REG *pLCD = (S3C2440A_LCD_REG*)OALPAtoVA(S3C2440A_BASE_REG_PA_LCD, FALSE);
RETAILMSG(1, (TEXT(":::E:/WINCE500/PLATFORM/SMDK2440A/Src/Common/Power/off.c/r/n")));
// First do platform specific actions
BSPPowerOff();
// Then save system registers
saveArea[0] = INPORT32(&pIOPort->GPACON);
saveArea[1] = INPORT32(&pIOPort->GPADAT);
saveArea[2] = INPORT32(&pIOPort->GPBCON);
saveArea[3] = INPORT32(&pIOPort->GPBDAT);
saveArea[4] = INPORT32(&pIOPort->GPBUP);
saveArea[5] = INPORT32(&pIOPort->GPCCON);
saveArea[6] = INPORT32(&pIOPort->GPCDAT);
saveArea[7] = INPORT32(&pIOPort->GPCUP);
saveArea[8] = INPORT32(&pIOPort->GPDCON);
saveArea[9] = INPORT32(&pIOPort->GPDDAT);
saveArea[10] = INPORT32(&pIOPort->GPDUP);
saveArea[11] = INPORT32(&pIOPort->GPECON);
saveArea[12] = INPORT32(&pIOPort->GPEDAT);
saveArea[13] = INPORT32(&pIOPort->GPEUP);
saveArea[14] = INPORT32(&pIOPort->GPFCON);
saveArea[15] = INPORT32(&pIOPort->GPFDAT);
saveArea[16] = INPORT32(&pIOPort->GPFUP);
saveArea[17] = INPORT32(&pIOPort->GPGCON);
saveArea[18] = INPORT32(&pIOPort->GPGDAT);
saveArea[19] = INPORT32(&pIOPort->GPGUP);
saveArea[20] = INPORT32(&pIOPort->GPHCON);
saveArea[21] = INPORT32(&pIOPort->GPHDAT);
saveArea[22] = INPORT32(&pIOPort->GPHUP);
saveArea[23] = INPORT32(&pIOPort->MISCCR);
saveArea[24] = INPORT32(&pIOPort->DCLKCON);
saveArea[25] = INPORT32(&pIOPort->EXTINT0);
saveArea[26] = INPORT32(&pIOPort->EXTINT1);
saveArea[27] = INPORT32(&pIOPort->EXTINT2);
saveArea[28] = INPORT32(&pIOPort->EINTFLT0);
saveArea[29] = INPORT32(&pIOPort->EINTFLT1);
saveArea[30] = INPORT32(&pIOPort->EINTFLT2);
saveArea[31] = INPORT32(&pIOPort->EINTFLT3);
saveArea[32] = INPORT32(&pIOPort->EINTMASK);
saveArea[33] = INPORT32(&pIntr->INTMOD);
saveArea[34] = INPORT32(&pIntr->INTMSK);
saveArea[35] = INPORT32(&pIntr->INTSUBMSK);
saveArea[36] = INPORT32(&pLCD->TCONSEL);
saveArea[37] = INPORT32(&pLCD->LCDINTMSK);
saveArea[38] = INPORT32(&pLCD->TPAL);
saveArea[39] = INPORT32(&pLCD->DITHMODE);
saveArea[40] = INPORT32(&pLCD->BLUELUT);
saveArea[41] = INPORT32(&pLCD->GREENLUT);
saveArea[42] = INPORT32(&pLCD->REDLUT);
saveArea[43] = INPORT32(&pLCD->LCDSADDR3);
saveArea[44] = INPORT32(&pLCD->LCDSADDR2);
saveArea[45] = INPORT32(&pLCD->LCDSADDR1);
saveArea[46] = INPORT32(&pLCD->LCDCON5);
saveArea[47] = INPORT32(&pLCD->LCDCON4);
saveArea[48] = INPORT32(&pLCD->LCDCON3);
saveArea[49] = INPORT32(&pLCD->LCDCON2);
saveArea[50] = INPORT32(&pLCD->LCDCON1);
pLCD->LCDCON1 = 0;
pLCD->LCDCON2 = 0;
pLCD->LCDCON3 = 0;
pLCD->LCDCON4 = 0;
pLCD->LCDCON5 = 0;
pLCD->LCDSADDR1 = 0;
pLCD->LCDSADDR2 = 0;
pLCD->LCDSADDR3 = 0;
pLCD->TCONSEL = 0;
pLCD->TPAL = 0;
ConfigStopGPIO();
// Switch off power for KITL device
OALKitlPowerOff(); // made_by_gmh
///////////////////////////GMH
//pIOPort->GPGCON &= 0xfcff;
// pIOPort->GPGCON |= 0x0300;
// pIOPort->GPGDAT &=0xef;
// RETAILMSG(1, (TEXT("::: pwr_en=0@josh915/r/n")));
/////////////////////////////////GMH_END
// Go to power off mode
OALCPUPowerOff();//這個函數就在starup.s中
之後進入oal的starup.s中
LEAF_ENTRY OALCPUPowerOff
; 1. Push SVC state onto our stack
stmdb sp!, {r4-r12}
stmdb sp!, {lr}
; 2. Save MMU & CPU Register to RAM
ldr r3, =SLEEPDATA_BASE_VIRTUAL ; base of Sleep mode storage
ldr r2, =Awake_address ; store Virtual return address
str r2, [r3], #4
mrc p15, 0, r2, c1, c0, 0 ; load r2 with MMU Control
ldr r0, =MMU_CTL_MASK ; mask off the undefined bits
bic r2, r2, r0
str r2, [r3], #4 ; store MMU Control data
mrc p15, 0, r2, c2, c0, 0 ; load r2 with TTB address.
ldr r0, =MMU_TTB_MASK ; mask off the undefined bits
bic r2, r2, r0
str r2, [r3], #4 ; store TTB address
mrc p15, 0, r2, c3, c0, 0 ; load r2 with domain access control.
str r2, [r3], #4 ; store domain access control
str sp, [r3], #4 ; store SVC stack pointer
mrs r2, spsr
str r2, [r3], #4 ; store SVC status register
mov r1, #Mode_FIQ:OR:I_Bit:OR:F_Bit ; Enter FIQ mode, no interrupts
msr cpsr, r1
mrs r2, spsr
stmia r3!, {r2, r8-r12, sp, lr} ; store the FIQ mode registers
mov r1, #Mode_ABT:OR:I_Bit:OR:F_Bit ; Enter ABT mode, no interrupts
msr cpsr, r1
mrs r0, spsr
stmia r3!, {r0, sp, lr} ; store the ABT mode Registers
mov r1, #Mode_IRQ:OR:I_Bit:OR:F_Bit ; Enter IRQ mode, no interrupts
msr cpsr, r1
mrs r0, spsr
stmia r3!, {r0, sp, lr} ; store the IRQ Mode Registers
mov r1, #Mode_UND:OR:I_Bit:OR:F_Bit ; Enter UND mode, no interrupts
msr cpsr, r1
mrs r0, spsr
stmia r3!, {r0, sp, lr} ; store the UND mode Registers
mov r1, #Mode_SYS:OR:I_Bit:OR:F_Bit ; Enter SYS mode, no interrupts
msr cpsr, r1
stmia r3!, {sp, lr} ; store the SYS mode Registers
mov r1, #Mode_SVC:OR:I_Bit:OR:F_Bit ; Back to SVC mode, no interrupts
msr cpsr, r1
; 3. do Checksum on the Sleepdata
ldr r3, =SLEEPDATA_BASE_VIRTUAL ; get pointer to SLEEPDATA
ldr r2, =0x0
ldr r0, =(SLEEPDATA_SIZE-1) ; get size of data structure (in words)
30
ldr r1, [r3], #4
and r1, r1, #0x1
mov r1, r1, ROR #31
add r2, r2, r1
subs r0, r0, #1
bne %b30
ldr r0, =vGPIOBASE
;;;add r2, r2, #1 ; test checksum of the Sleep data error
str r2, [r0, #oGSTATUS3] ; Store in Power Manager Scratch pad register
ldr r0, =vGPIOBASE
ldr r1, =0x550a
str r1, [r0, #oGPFCON]
ldr r1, =0x30
str r1, [r0, #oGPFDAT]
; 4. Interrupt Disable
ldr r0, =vINTBASE
mvn r2, #0
str r2, [r0, #oINTMSK]
str r2, [r0, #oSRCPND]
str r2, [r0, #oINTPND]
;; 5. Cache Flush
bl OALClearUTLB
bl OALFlushICache
ldr r0, = (DCACHE_LINES_PER_SET - 1)
ldr r1, = (DCACHE_NUM_SETS - 1)
ldr r2, = DCACHE_SET_INDEX_BIT
ldr r3, = DCACHE_LINE_SIZE
bl OALFlushDCache
; 6. Setting Wakeup External Interrupt(EINT0,1,2) Mode
ldr r0, =vGPIOBASE
ldr r1, =0x550a
str r1, [r0, #oGPFCON]
; ldr r1, =0x55550100
; str r1, [r0, #oGPGCON]
; 7. Go to Power-Off Mode
ldr r0, =vMISCCR ; hit the TLB
ldr r0, [r0]
ldr r0, =vCLKCON
ldr r0, [r0]
ldr r0, =vREFRESH
ldr r1, [r0] ; r1=rREFRESH
orr r1, r1, #(1 << 22)
ldr r2, =vMISCCR
ldr r3, [r2]
orr r3, r3, #(7<<17) ; Make sure that SCLK0:SCLK->0, SCLK1:SCLK->0, SCKE=L during boot-up
bic r3, r3, #(7<<20)
orr r3, r3, #(6<<20)
ldr r4, =vCLKCON
ldr r5, =0x1ffff8 ; Power Off Mode
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Sometimes it is not working in cache mode. So I modify to jump to ROM area.
;
;;; ldr r6, =0x92000000 ; make address to 0x9200 0020
;;; add r6, r6, #0x20 ;
;;; mov pc, r6 ; jump to Power off code in ROM
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
b SelfRefreshAndPowerOff
ALIGN 32 ; for I-Cache Line(32Byte, 8 Word)
SelfRefreshAndPowerOff ; run with Instruction Cache's code
str r1, [r0] ; Enable SDRAM self-refresh
str r3, [r2] ; MISCCR Setting
str r5, [r4] ; Power Off !!
b .
這個彙編代碼實現真正的休眠設置，系統能一步步執行下來，執行到最後，系統電流下降了100多ma，sclk0等時鐘信號也變0了，但是lcd控制信號pwren由3.3降到2.3v左右，lcd沒有被關閉，出現了白屏，也就是系統沒有真正進入休眠中。可能有人會說，直接用io把pwren設置爲0，可是系統已經設置過了，在
BSPPowerOff();函數中：
/* LCD Controller Disable */
CLRPORT32(&pIOPort->GPGDAT, 1 << 4);
已經設置過，即使強制把lcd背光關了，電流也只能再少100多ma，還有200多ma的電流，我猜想內核其實沒有真正休眠下來，假如真的休眠了，lcd也會真正被關閉
對比了很多網上的bsp，基本上也差不多，沒多大區別，，不知道原因出在哪裏
映射地址情況如下
SLEEPDATA_BASE_VIRTUAL EQU 0xA0028000 ; keep in sync w/ config.bib
SLEEPDATA_BASE_PHYSICAL EQU 0x30028000
config.bib：MEMORY
NK 80200000 02200000 RAMIMAGE
; RAM 82400000 05c00000 RAM
RAM 82400000 01c00000 RAM