Использую готовый пример от IAR - getting-started-project.
При компиляции и запуску программы из-под IAR или посредством SAM-BA все нормально работает.
Подскажите как правильно переделать board_cstartup_iar.s чтобы загрузка производилась из NAND Flash?
CODE
MODULE ?cstartup
;; Forward declaration of sections.
SECTION IRQ_STACK:DATA:NOROOT(2)
SECTION CSTACK:DATA:NOROOT(3)
//------------------------------------------------------------------------------
// Headers
//------------------------------------------------------------------------------
#define __ASSEMBLY__
#include "board.h"
//------------------------------------------------------------------------------
// Definitions
//------------------------------------------------------------------------------
#define ARM_MODE_ABT 0x17
#define ARM_MODE_FIQ 0x11
#define ARM_MODE_IRQ 0x12
#define ARM_MODE_SVC 0x13
#define ARM_MODE_SYS 0x1F
#define I_BIT 0x80
#define F_BIT 0x40
//------------------------------------------------------------------------------
// Startup routine
//------------------------------------------------------------------------------
/*
Exception vectors
*/
SECTION .vectors:CODE:NOROOT(2)
PUBLIC resetVector
PUBLIC irqHandler
EXTERN Undefined_Handler
EXTERN SWI_Handler
EXTERN Prefetch_Handler
EXTERN Abort_Handler
EXTERN FIQ_Handler
ARM
__iar_init$$done: ; The interrupt vector is not needed
; until after copy initialization is done
resetVector:
; All default exception handlers (except reset) are
; defined as weak symbol definitions.
; If a handler is defined by the application it will take precedence.
LDR pc, =resetHandler ; Reset
LDR pc, Undefined_Addr ; Undefined instructions
LDR pc, SWI_Addr ; Software interrupt (SWI/SYS)
LDR pc, Prefetch_Addr ; Prefetch abort
LDR pc, Abort_Addr ; Data abort
B . ; RESERVED
LDR pc, =irqHandler ; IRQ
LDR pc, FIQ_Addr ; FIQ
Undefined_Addr: DCD Undefined_Handler
SWI_Addr: DCD SWI_Handler
Prefetch_Addr: DCD Prefetch_Handler
Abort_Addr: DCD Abort_Handler
FIQ_Addr: DCD FIQ_Handler
/*
Handles incoming interrupt requests by branching to the corresponding
handler, as defined in the AIC. Supports interrupt nesting.
*/
irqHandler:
/* Save interrupt context on the stack to allow nesting */
SUB lr, lr, #4
STMFD sp!, {lr}
MRS lr, SPSR
STMFD sp!, {r0, lr}
/* Write in the IVR to support Protect Mode */
LDR lr, =AT91C_BASE_AIC
LDR r0, [r14, #AIC_IVR]
STR lr, [r14, #AIC_IVR]
/* Branch to interrupt handler in Supervisor mode */
MSR CPSR_c, #ARM_MODE_SYS
STMFD sp!, {r1-r3, r4, r12, lr}
/* Check for 8-byte alignment and save lr plus a */
/* word to indicate the stack adjustment used (0 or 4) */
AND r1, sp, #4
SUB sp, sp, r1
STMFD sp!, {r1, lr}
BLX r0
LDMIA sp!, {r1, lr}
ADD sp, sp, r1
LDMIA sp!, {r1-r3, r4, r12, lr}
MSR CPSR_c, #ARM_MODE_IRQ | I_BIT
/* Acknowledge interrupt */
LDR lr, =AT91C_BASE_AIC
STR lr, [r14, #AIC_EOICR]
/* Restore interrupt context and branch back to calling code */
LDMIA sp!, {r0, lr}
MSR SPSR_cxsf, lr
LDMIA sp!, {pc}^
/*
After a reset, execution starts here, the mode is ARM, supervisor
with interrupts disabled.
Initializes the chip and branches to the main() function.
*/
SECTION .cstartup:CODE:NOROOT(2)
PUBLIC resetHandler
EXTERN LowLevelInit
EXTERN ?main
REQUIRE resetVector
ARM
resetHandler:
/* Set pc to actual code location (i.e. not in remap zone) */
LDR pc, =label
/* Perform low-level initialization of the chip using LowLevelInit() */
label:
LDR r0, =LowLevelInit
LDR r4, =SFE(CSTACK)
MOV sp, r4
BLX r0
/* Set up the interrupt stack pointer. */
MSR cpsr_c, #ARM_MODE_IRQ | I_BIT | F_BIT ; Change the mode
LDR sp, =SFE(IRQ_STACK)
/* Set up the SYS stack pointer. */
MSR cpsr_c, #ARM_MODE_SYS | F_BIT ; Change the mode
LDR sp, =SFE(CSTACK)
/* Branch to main() */
LDR r0, =?main
BLX r0
/* Loop indefinitely when program is finished */
loop4:
B loop4
END
В разделе resetHandler: присутствет процедура LowLevelInit ()
CODE
void LowLevelInit( void )
{
unsigned char i;
#if !defined(sdram)
/* Initialize main oscillator
****************************/
AT91C_BASE_PMC->PMC_MOR = BOARD_OSCOUNT | AT91C_CKGR_MOSCEN;
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MOSCS));
/* Initialize PLLA at 200MHz (198.656) */
AT91C_BASE_PMC->PMC_PLLAR = BOARD_CKGR_PLLA
| BOARD_PLLACOUNT
| BOARD_MULA
| BOARD_DIVA;
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_LOCKA));
/* Wait for the master clock if it was already initialized */
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY));
/* Switch to fast clock
**********************/
/* Switch to main oscillator + prescaler */
AT91C_BASE_PMC->PMC_MCKR = BOARD_PRESCALER;
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY));
/* Switch to PLL + prescaler */
AT91C_BASE_PMC->PMC_MCKR |= AT91C_PMC_CSS_PLLA_CLK;
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY));
#endif //#if !defined(sdram)
/* Initialize AIC
****************/
AT91C_BASE_AIC->AIC_IDCR = 0xFFFFFFFF;
AT91C_BASE_AIC->AIC_SVR[0] = (unsigned int) defaultFiqHandler;
for (i = 1; i < 31; i++) {
AT91C_BASE_AIC->AIC_SVR[i] = (unsigned int) defaultIrqHandler;
}
AT91C_BASE_AIC->AIC_SPU = (unsigned int) defaultSpuriousHandler;
// Unstack nested interrupts
for (i = 0; i < 8 ; i++) {
AT91C_BASE_AIC->AIC_EOICR = 0;
}
// Enable Debug mode
//AT91C_BASE_AIC->AIC_DCR = AT91C_AIC_DCR_PROT;
/* Watchdog initialization
*************************/
AT91C_BASE_WDTC->WDTC_WDMR = AT91C_WDTC_WDDIS;
/* Remap
*******/
BOARD_RemapRam();
// Disable RTT and PIT interrupts (potential problem when program A
// configures RTT, then program B wants to use PIT only, interrupts
// from the RTT will still occur since they both use AT91C_ID_SYS)
AT91C_BASE_RTTC->RTTC_RTMR &= ~(AT91C_RTTC_ALMIEN | AT91C_RTTC_RTTINCIEN);
AT91C_BASE_PITC->PITC_PIMR &= ~AT91C_PITC_PITIEN;
}
BOARD_RemapRam();
CODE
void BOARD_RemapRam(void)
{
WRITE(AT91C_BASE_MATRIX, MATRIX_MRCR, (AT91C_MATRIX_RCA926I | AT91C_MATRIX_RCA926D));
}
Везде написано о необходимости делать РЕМАП, но как понять не могу.
В 14 разделе описания на процессор говорится, что первые 28 байт должны соответствовать формату загрузчика. по смещению 0х14 указывается размер программы. Сразу возникает вопросы
- как в IAR автоматически при компиляции записать размер программы в bin-файл?
- каков формат этих 28 байт которые должны находиться в начале bin-файла? или необходимо произвести хитрые манипуляции в настройках самого IAR?
Сообщение отредактировал ANTSIR - May 11 2010, 12:11
Освоением ARM - запуск программы из NAND Flash, AT91SAM9RL-EK
May 11 2010, 12:09
