about ARM-assemble code

[박범규 연구원]

Hello, master. I'm glad to find this site, and thanks.   I'm on study of kernel, porting linux to arm-core processor. I read source, which is assemble code.  I can't understand, can't find any doc about that.   Please, guide me.   kernel ver 2.2.2 /linux/include/asm-arm/proc-armv/*   ==========in semaphore.h=================== extern inline void down(struct semaphore * sem) {  unsigned int cpsr, temp;    __asm__ __volatile__ ("  @ atomic down operation  mrs %0, cpsr  orr %1, %0, #128  @ disable IRQs  bic %0, %0, #0x80000000 @ clear N  msr cpsr, %1  ldr %1, [%2]  subs %1, %1, #1  orrmi %0, %0, #0x80000000 @ set N  str %1, [%2]  msr cpsr, %0  movmi r0, %2  blmi " SYMBOL_NAME_STR(__down_failed)   : "=&r" (cpsr), "=&r" (temp)   : "r" (sem)   : "r0", "lr", "cc"); } =============================================   help me reading this code,  have good luck, trimendous achievement. good bye. ������ ������� TEL  02-522-8370 FAX  02-522-8370