Call this function unconditionally so that we can populate an empty DTB on platforms that don't boot with a firmware provided or builtin DTB. There's no harm in calling unflatten_device_tree() unconditionally here. If there isn't a non-NULL 'initial_boot_params' pointer then unflatten_device_tree() returns early. Cc: Rob Herring <robh+dt@xxxxxxxxxx> Cc: Frank Rowand <frowand.list@xxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: <x86@xxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Tested-by: Saurabh Sengar <ssengar@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx> --- arch/x86/kernel/devicetree.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c index afd09924094e..650752d112a6 100644 --- a/arch/x86/kernel/devicetree.c +++ b/arch/x86/kernel/devicetree.c @@ -283,22 +283,24 @@ void __init x86_flattree_get_config(void) u32 size, map_len; void *dt; - if (!initial_dtb) - return; + if (initial_dtb) { + map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128); - map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128); + dt = early_memremap(initial_dtb, map_len); + size = fdt_totalsize(dt); + if (map_len < size) { + early_memunmap(dt, map_len); + dt = early_memremap(initial_dtb, size); + map_len = size; + } - dt = early_memremap(initial_dtb, map_len); - size = fdt_totalsize(dt); - if (map_len < size) { - early_memunmap(dt, map_len); - dt = early_memremap(initial_dtb, size); - map_len = size; + early_init_dt_verify(dt); } - early_init_dt_verify(dt); unflatten_and_copy_device_tree(); - early_memunmap(dt, map_len); + + if (initial_dtb) + early_memunmap(dt, map_len); } #endif -- https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git/ https://git.kernel.org/pub/scm/linux/kernel/git/sboyd/spmi.git