powerpc/32: Pass device tree address as u64 to machine_init

u64 is used rather than phys_addr_t to keep things simple, as
this is called from assembly code.

Update callers to pass a 64-bit address in r3/r4.  Other unused
register assignments that were once parameters to machine_init
are dropped.

For FSL BookE, look up the physical address of the device tree from the
effective address passed in r3 by the loader.  This is required for
situations where memory does not start at zero (due to AMP or IOMMU-less
virtualization), and thus the IMA doesn't start at zero, and thus the
device tree effective address does not equal the physical address.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 3 insertions, 4 deletions

diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index ba250d505e07..0654dba2c1f1 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -139,8 +139,7 @@ __start:
         trap
 #endif /* CONFIG_PPC_PMAC */
 
-1:      mr      r31,r3                  /* save parameters */
-        mr      r30,r4
+1:      mr      r31,r3                  /* save device tree ptr */
         li      r24,0                   /* cpu # */
 
 /*
@@ -964,8 +963,8 @@ start_here:
  * Do early platform-specific initialization,
  * and set up the MMU.
  */
-        mr      r3,r31
-        mr      r4,r30
+        li      r3,0
+        mr      r4,r31
         bl      machine_init
         bl      __save_cpu_setup
         bl      MMU_init