Device tree ARM machine desc has been allocated id 0xffffffff temporarily.
This machine id should be passed in r1 upon kernel booting.
Legacy code requires code stubs to update r1 accordingly when
booting from legacy boot loaders that do not necessarily pass DT
mach id on r1.

This patch adds code in the dtb stub to automatically generate and move
the required DT machine id into r1 before jumping to kernel code.

Signed-off-by: Lorenzo Pieralisi <[email protected]>
---
 arch/arm/boot/dt/dtb.S |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/arch/arm/boot/dt/dtb.S b/arch/arm/boot/dt/dtb.S
index e678db2..7d56289 100644
--- a/arch/arm/boot/dt/dtb.S
+++ b/arch/arm/boot/dt/dtb.S
@@ -35,6 +35,9 @@ setup_dtb:
        cmp     r4, r5
        blo     2b
 
+       /* update r1 with DT id  */
+       mvn     r1, #0x0
+
        b       zimage_start
 
        .ltorg
-- 
1.6.3.3

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