linux-sg2042/arch/x86/kernel/trampoline.c

34 lines
934 B
C

#include <linux/io.h>
#include <asm/trampoline.h>
#include <asm/e820.h>
/* ready for x86_64 and x86 */
unsigned char *trampoline_base = __va(TRAMPOLINE_BASE);
void __init reserve_trampoline_memory(void)
{
#ifdef CONFIG_X86_32
/*
* But first pinch a few for the stack/trampoline stuff
* FIXME: Don't need the extra page at 4K, but need to fix
* trampoline before removing it. (see the GDT stuff)
*/
reserve_early(PAGE_SIZE, PAGE_SIZE + PAGE_SIZE, "EX TRAMPOLINE");
#endif
/* Has to be in very low memory so we can execute real-mode AP code. */
reserve_early(TRAMPOLINE_BASE, TRAMPOLINE_BASE + TRAMPOLINE_SIZE,
"TRAMPOLINE");
}
/*
* Currently trivial. Write the real->protected mode
* bootstrap into the page concerned. The caller
* has made sure it's suitably aligned.
*/
unsigned long setup_trampoline(void)
{
memcpy(trampoline_base, trampoline_data, TRAMPOLINE_SIZE);
return virt_to_phys(trampoline_base);
}