/**************************************************************************
MEMSIZE - Determine size of extended memory
**************************************************************************/
unsigned int memsize ( void )
{
struct {
reg16_t ax;
} PACKED in_stack;
struct {
reg16_t ax;
reg16_t bx;
reg16_t cx;
reg16_t dx;
reg16_t flags;
} PACKED out_stack;
int memsize;
RM_FRAGMENT(rm_memsize,
/* Some buggy BIOSes don't clear/set carry on pass/error of
* e801h memory size call or merely pass cx,dx through without
* changing them, so we set carry and zero cx,dx before call.
*/
"stc\n\t"
"xorw %cx,%cx\n\t"
"xorw %dx,%dx\n\t"
"popw %ax\n\t"
"int $0x15\n\t"
"pushfw\n\t"
"pushw %dx\n\t"
"pushw %cx\n\t"
"pushw %bx\n\t"
"pushw %ax\n\t"
);
/* Try INT 15,e801 first */
in_stack.ax.word = 0xe801;
real_call ( rm_memsize, &in_stack, &out_stack );
if ( out_stack.flags.word & CF ) {
/* INT 15,e801 not supported: try INT 15,88 */
in_stack.ax.word = 0x8800;
memsize = real_call ( rm_memsize, &in_stack, &out_stack );
} else {
/* Some BIOSes report extended memory via ax,bx rather
* than cx,dx
*/
if ( (out_stack.cx.word==0) && (out_stack.dx.word==0) ) {
/* Use ax,bx */
memsize = ( out_stack.bx.word<<6 ) + out_stack.ax.word;
} else {
/* Use cx,dx */
memsize = ( out_stack.dx.word<<6 ) + out_stack.cx.word;
}
}
return memsize;
}
/**************************************************************************
BASEMEMSIZE - Get size of the conventional (base) memory
**************************************************************************/
unsigned short basememsize ( void )
{
RM_FRAGMENT(rm_basememsize,
"int $0x12\n\t"
);
return real_call ( rm_basememsize, NULL, NULL );
}
int vesa_set_vbe_mode(unsigned short mode)
{
unsigned int handle_irq = irq_lock();
irq_unmap();
int result = real_call(real_set_vbe_mode_id, mode);
irq_remap();
irq_unlock(handle_irq);
return result;
}
struct vesa_vbe_mode_info* vesa_get_vbe_mode_info(unsigned short mode)
{
unsigned int handle_irq = irq_lock();
irq_unmap();
struct vesa_vbe_mode_info* result = (struct vesa_vbe_mode_info*)real_call(real_get_vbe_mode_info_id, mode);
irq_remap();
irq_unlock(handle_irq);
return result;
}
int meme820 ( struct e820entry *buf, int count )
{
struct {
reg16_t flags;
reg32_t eax;
reg32_t ebx;
struct e820entry entry;
} PACKED stack;
int index = 0;
#ifdef VBOX
RM_FRAGMENT(rm_meme820,
"addw $6, %sp\n\t" /* skip flags, eax */
"popl %ebx\n\t"
"pushw %ss\n\t" /* es:di = ss:sp */
"popw %es\n\t"
"movw %sp, %di\n\t"
"movl $0xe820, %eax\n\t"
"movl $" STRINGIFY(SMAP) ", %edx\n\t"
"movl $" STRINGIFY(E820ENTRY_SIZE) ", %ecx\n\t"
"int $0x15\n\t"
"pushl %ebx\n\t"
"pushl %eax\n\t"
"pushfw\n\t"
);
#else /* !VBOX */
RM_FRAGMENT(rm_meme820,
"addw $6, %sp\n\t" /* skip flags, eax */
"popl %ebx\n\t"
"pushw %ss\n\t" /* es:di = ss:sp */
"popw %es\n\t"
"movw %sp, %di\n\t"
"movl $0xe820, %eax\n\t"
"movl $" RM_STR(SMAP) ", %edx\n\t"
"movl $" RM_STR(E820ENTRY_SIZE) ", %ecx\n\t"
"int $0x15\n\t"
"pushl %ebx\n\t"
"pushl %eax\n\t"
"pushfw\n\t"
);
#endif /* !VBOX */
stack.ebx.dword = 0; /* 'EOF' marker */
while ( ( index < count ) &&
( ( index == 0 ) || ( stack.ebx.dword != 0 ) ) ) {
real_call ( rm_meme820, &stack, &stack );
if ( stack.eax.dword != SMAP ) return 0;
if ( stack.flags.word & CF ) return 0;
buf[index++] = stack.entry;
}
return index;
}
