[PATCH] powerpc: Add back support for booting from BootX (#2)
ARCH=powerpc couldn't boot from BootX as it uses a "different" way of
getting in the kernel. This patch adds the necessary trampolines,
creating a flattened device-tree from the tree passed from MacOS, and
initializing the btext engine early for really-early debugging.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index fdd34db..6359e36 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -125,6 +125,19 @@
bl prom_init
trap
+/*
+ * Check for BootX signature when supporting PowerMac and branch to
+ * appropriate trampoline if it's present
+ */
+#ifdef CONFIG_PPC_PMAC
+1: lis r31,0x426f
+ ori r31,r31,0x6f58
+ cmpw 0,r3,r31
+ bne 1f
+ bl bootx_init
+ trap
+#endif /* CONFIG_PPC_PMAC */
+
1: mr r31,r3 /* save parameters */
mr r30,r4
li r24,0 /* cpu # */