43 lines
1.3 KiB
C
43 lines
1.3 KiB
C
#include <linux/io.h>
|
|
#include <linux/memblock.h>
|
|
|
|
#include <asm/trampoline.h>
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/pgtable.h>
|
|
|
|
unsigned char *x86_trampoline_base;
|
|
|
|
void __init setup_trampolines(void)
|
|
{
|
|
phys_addr_t mem;
|
|
size_t size = PAGE_ALIGN(x86_trampoline_end - x86_trampoline_start);
|
|
|
|
/* Has to be in very low memory so we can execute real-mode AP code. */
|
|
mem = memblock_find_in_range(0, 1<<20, size, PAGE_SIZE);
|
|
if (mem == MEMBLOCK_ERROR)
|
|
panic("Cannot allocate trampoline\n");
|
|
|
|
x86_trampoline_base = __va(mem);
|
|
memblock_x86_reserve_range(mem, mem + size, "TRAMPOLINE");
|
|
|
|
printk(KERN_DEBUG "Base memory trampoline at [%p] %llx size %zu\n",
|
|
x86_trampoline_base, (unsigned long long)mem, size);
|
|
|
|
memcpy(x86_trampoline_base, x86_trampoline_start, size);
|
|
}
|
|
|
|
/*
|
|
* setup_trampolines() gets called very early, to guarantee the
|
|
* availability of low memory. This is before the proper kernel page
|
|
* tables are set up, so we cannot set page permissions in that
|
|
* function. Thus, we use an arch_initcall instead.
|
|
*/
|
|
static int __init configure_trampolines(void)
|
|
{
|
|
size_t size = PAGE_ALIGN(x86_trampoline_end - x86_trampoline_start);
|
|
|
|
set_memory_x((unsigned long)x86_trampoline_base, size >> PAGE_SHIFT);
|
|
return 0;
|
|
}
|
|
arch_initcall(configure_trampolines);
|