ARM: 5884/1: arm: Fix DCC console for v7
Without this patch arch/arm/compressed/head.S defaults to generic
DCC code that does not work for v7.
For more information on the v7 DCC, see Cortex-A8 TRM
"12.11.1 Debug communications channel".
To use it with post 2.6.33-rc1 or later, you need to have:
CONFIG_DEBUG_LL=y
ONFIG_DEBUG_ICEDCC=y
CONFIG_EARLY_PRINTK=y
Earlier kernels need commit 93fd03a8c6728b58879f8af20ffd55d9c32a778b
backported.
Tested on omap3430.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index d356af7..4fddc50 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -27,6 +27,14 @@
.macro writeb, ch, rb
mcr p14, 0, \ch, c0, c5, 0
.endm
+#elif defined(CONFIG_CPU_V7)
+ .macro loadsp, rb
+ .endm
+ .macro writeb, ch, rb
+wait: mrc p14, 0, pc, c0, c1, 0
+ bcs wait
+ mcr p14, 0, \ch, c0, c5, 0
+ .endm
#elif defined(CONFIG_CPU_XSCALE)
.macro loadsp, rb
.endm