efi/fdt: Set address/size cells to 2 for empty tree

When booting an arm* system on UEFI with an empty device tree (currently
only when hardware description comes from ACPI), we don't currently set
default to 1 cell (32 bits).

Set both of these properties, to 2 cells (64 bits), to resolve issues
with kexec on some platforms.

This change corresponds with linux kernel commit ae8a442dfdc4
("efi/libstub/arm*: Set default address and size cells values for an empty dtb")
and ensures booting through grub does not behave differently from booting
the stub loader directly.

See also https://patchwork.kernel.org/patch/9561201/

Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This commit is contained in:
Leif Lindholm 2018-06-11 17:24:59 +01:00 committed by Daniel Kiper
parent e93fd6b776
commit 347210a5d5

View file

@ -29,6 +29,12 @@
static void *loaded_fdt;
static void *fdt;
#define FDT_ADDR_CELLS_STRING "#address-cells"
#define FDT_SIZE_CELLS_STRING "#size-cells"
#define FDT_ADDR_SIZE_EXTRA ((2 * grub_fdt_prop_entry_size (sizeof(grub_uint32_t))) + \
sizeof (FDT_ADDR_CELLS_STRING) + \
sizeof (FDT_SIZE_CELLS_STRING))
void *
grub_fdt_load (grub_size_t additional_size)
{
@ -46,8 +52,11 @@ grub_fdt_load (grub_size_t additional_size)
else
raw_fdt = grub_efi_get_firmware_fdt();
size =
raw_fdt ? grub_fdt_get_totalsize (raw_fdt) : GRUB_FDT_EMPTY_TREE_SZ;
if (raw_fdt)
size = grub_fdt_get_totalsize (raw_fdt);
else
size = GRUB_FDT_EMPTY_TREE_SZ + FDT_ADDR_SIZE_EXTRA;
size += additional_size;
grub_dprintf ("linux", "allocating %d bytes for fdt\n", size);
@ -63,6 +72,8 @@ grub_fdt_load (grub_size_t additional_size)
else
{
grub_fdt_create_empty_tree (fdt, size);
grub_fdt_set_prop32 (fdt, 0, FDT_ADDR_CELLS_STRING, 2);
grub_fdt_set_prop32 (fdt, 0, FDT_SIZE_CELLS_STRING, 2);
}
return fdt;
}