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>

1 files changed, 20 insertions, 0 deletions

diff --git a/arch/arm/kernel/debug.S b/arch/arm/kernel/debug.S
index b121b6053cce..5c91addcaebc 100644
--- a/arch/arm/kernel/debug.S
+++ b/arch/arm/kernel/debug.S
@@ -49,6 +49,26 @@
 1002:
                 .endm
 
+#elif defined(CONFIG_CPU_V7)
+
+                .macro  addruart, rx
+                .endm
+
+                .macro  senduart, rd, rx
+                mcr     p14, 0, \rd, c0, c5, 0
+                .endm
+
+                .macro  busyuart, rd, rx
+busy:           mrc     p14, 0, pc, c0, c1, 0
+                bcs     busy
+                .endm
+
+                .macro  waituart, rd, rx
+wait:           mrc     p14, 0, pc, c0, c1, 0
+                bcs     wait
+
+                .endm
+
 #elif defined(CONFIG_CPU_XSCALE)
 
                 .macro  addruart, rx