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/* Etherboot routines for PCBIOS firmware.
*
* Body of routines taken from old pcbios.S
*/
#include <stdint.h>
#include <realmode.h>
#include <bios.h>
#define CF ( 1 << 0 )
/**************************************************************************
CURRTICKS - Get Time
Use direct memory access to BIOS variables, longword 0040:006C (ticks
today) and byte 0040:0070 (midnight crossover flag) instead of calling
timeofday BIOS interrupt.
**************************************************************************/
#if defined(CONFIG_TSC_CURRTICKS)
#undef CONFIG_BIOS_CURRTICKS
#else
#define CONFIG_BIOS_CURRTICKS 1
#endif
#if defined(CONFIG_BIOS_CURRTICKS)
unsigned long currticks ( void ) {
static uint32_t days = 0;
uint32_t ticks;
uint8_t midnight;
/* Re-enable interrupts so that the timer interrupt can occur
*/
__asm__ __volatile__ ( REAL_CODE ( "sti\n\t"
"nop\n\t"
"nop\n\t"
"cli\n\t" ) : : );
get_real ( ticks, BDA_SEG, 0x006c );
get_real ( midnight, BDA_SEG, 0x0070 );
if ( midnight ) {
midnight = 0;
put_real ( midnight, BDA_SEG, 0x0070 );
days += 0x1800b0;
}
return ( days + ticks );
}
#endif /* CONFIG_BIOS_CURRTICKS */
/**************************************************************************
CPU_NAP - Save power by halting the CPU until the next interrupt
**************************************************************************/
void cpu_nap ( void ) {
__asm__ __volatile__ ( REAL_CODE ( "sti\n\t"
"hlt\n\t"
"cli\n\t" ) : : );
}
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