[PATCH v2 1/7] arm64: Unconditionally call unflatten_device_tree()

[Stephen Boyd <sboyd@kernel.org>]

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.
Override 'initial_boot_params' to NULL when ACPI is in use but the
bootloader has loaded a DTB so that we don't allow both ACPI and DT to
be used during boot. If there isn't a valid initial_boot_params dtb then
unflatten_device_tree() returns early so this is fine.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
---
 arch/arm64/kernel/setup.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 417a8a86b2db..ffb1942724ae 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -351,8 +351,11 @@ void __init __no_sanitize_address setup_arch(char **cmdline_p)
 	/* Parse the ACPI tables for possible boot-time configuration */
 	acpi_boot_table_init();
 
-	if (acpi_disabled)
-		unflatten_device_tree();
+	/* Don't use the FDT from boot if ACPI is in use */
+	if (!acpi_disabled)
+		initial_boot_params = NULL;
+
+	unflatten_device_tree();
 
 	bootmem_init();
 
-- 
https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git/
https://git.kernel.org/pub/scm/linux/kernel/git/sboyd/spmi.git