Support >3GiB and < 16MiB of RAM in i386-qemu

This commit is contained in:
Vladimir 'phcoder' Serbinenko 2010-06-20 14:17:56 +02:00
parent 0e489b8233
commit 6d5a33c9ac

View file

@ -27,21 +27,37 @@
#define QEMU_CMOS_MEMSIZE_HIGH 0x35
#define QEMU_CMOS_MEMSIZE_LOW 0x34
#define QEMU_CMOS_MEMSIZE2_HIGH 0x31
#define QEMU_CMOS_MEMSIZE2_LOW 0x30
#define min(a,b) ((a) > (b) ? (b) : (a))
extern char _start[];
extern char _end[];
grub_size_t grub_lower_mem, grub_upper_mem;
grub_uint64_t mem_size;
static grub_uint64_t mem_size, above_4g;
void
grub_machine_mmap_init ()
{
mem_size = grub_cmos_read (QEMU_CMOS_MEMSIZE_HIGH) << 24 | grub_cmos_read (QEMU_CMOS_MEMSIZE_LOW) << 16;
mem_size = ((grub_uint64_t) grub_cmos_read (QEMU_CMOS_MEMSIZE_HIGH)) << 24
| ((grub_uint64_t) grub_cmos_read (QEMU_CMOS_MEMSIZE_LOW)) << 16;
if (mem_size > 0)
{
/* Don't ask... */
mem_size += (16 * 1024 * 1024);
}
else
{
mem_size
= ((((grub_uint64_t) grub_cmos_read (QEMU_CMOS_MEMSIZE2_HIGH)) << 18)
| ((grub_uint64_t) (grub_cmos_read (QEMU_CMOS_MEMSIZE2_LOW)) << 10))
+ 1024 * 1024;
}
/* Don't ask... */
mem_size += (16 * 1024 * 1024);
above_4g = (((grub_uint64_t) grub_cmos_read (0x5b)) << 16)
| (((grub_uint64_t) grub_cmos_read (0x5c)) << 24)
| (((grub_uint64_t) grub_cmos_read (0x5d)) << 32);
}
grub_err_t
@ -57,6 +73,12 @@ grub_machine_mmap_iterate (int NESTED_FUNC_ATTR (*hook) (grub_uint64_t, grub_uin
GRUB_MACHINE_MEMORY_RESERVED))
return 1;
/* Everything else is free. */
if (hook (0x100000,
min (mem_size, (grub_uint32_t) -GRUB_BOOT_MACHINE_SIZE) - 0x100000,
GRUB_MACHINE_MEMORY_AVAILABLE))
return 1;
/* Protect boot.img, which contains the gdt. It is mapped at the top of memory
(it is also mapped below 0x100000, but we already reserved that area). */
if (hook ((grub_uint32_t) -GRUB_BOOT_MACHINE_SIZE,
@ -64,10 +86,8 @@ grub_machine_mmap_iterate (int NESTED_FUNC_ATTR (*hook) (grub_uint64_t, grub_uin
GRUB_MACHINE_MEMORY_RESERVED))
return 1;
/* Everything else is free. */
if (hook (0x100000,
min (mem_size, (grub_uint32_t) -GRUB_BOOT_MACHINE_SIZE) - 0x100000,
GRUB_MACHINE_MEMORY_AVAILABLE))
if (above_4g != 0 && hook (0x100000000ULL, above_4g,
GRUB_MACHINE_MEMORY_AVAILABLE))
return 1;
return 0;