[RFC] xenon: udbg support (ugly)

This adds support for a serial kernel output on the Xenon platform.

Signed-off-by: Felix Domke <tmbinc@elitedvb.net>

---
 arch/powerpc/Kconfig.debug            |    6 ++++++
 arch/powerpc/kernel/misc_64.S         |    2 +-
 arch/powerpc/kernel/udbg.c            |    2 ++
 arch/powerpc/platforms/xenon/Makefile |    2 +-
 arch/powerpc/platforms/xenon/udbg.c   |   20 ++++++++++++++++++++
 5 files changed, 30 insertions(+), 2 deletions(-)

Index: linux-2.6.21/arch/powerpc/kernel/misc_64.S
===================================================================
--- linux-2.6.21.orig/arch/powerpc/kernel/misc_64.S	2007-05-01 14:12:29.000000000 +0200
+++ linux-2.6.21/arch/powerpc/kernel/misc_64.S	2007-05-01 14:12:33.000000000 +0200
@@ -247,7 +247,7 @@
 	blr
 
 
-#if defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE)
+#if defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE) || defined(CONFIG_PPC_XENON)
 /*
  * Do an IO access in real mode
  */
Index: linux-2.6.21/arch/powerpc/kernel/udbg.c
===================================================================
--- linux-2.6.21.orig/arch/powerpc/kernel/udbg.c	2007-05-01 14:12:29.000000000 +0200
+++ linux-2.6.21/arch/powerpc/kernel/udbg.c	2007-05-01 14:12:33.000000000 +0200
@@ -51,6 +51,8 @@
 	udbg_init_pas_realmode();
 #elif defined(CONFIG_BOOTX_TEXT)
 	udbg_init_btext();
+#elif defined(CONFIG_PPC_EARLY_DEBUG_XENON)
+	udbg_init_xenon();
 #endif
 }
 
Index: linux-2.6.21/arch/powerpc/Kconfig.debug
===================================================================
--- linux-2.6.21.orig/arch/powerpc/Kconfig.debug	2007-05-01 14:12:29.000000000 +0200
+++ linux-2.6.21/arch/powerpc/Kconfig.debug	2007-05-01 14:12:33.000000000 +0200
@@ -199,6 +199,12 @@
 	help
 	  Select this to enable early debugging for Celleb with Beat.
 
+config PPC_EARLY_DEBUG_XENON
+	bool "Xenon serial port"
+	depends on PPC_XENON
+	help
+	  Select this to enable early debugging via Xenon serial port.
+
 endchoice
 
 endmenu
Index: linux-2.6.21/arch/powerpc/platforms/xenon/udbg.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.21/arch/powerpc/platforms/xenon/udbg.c	2007-05-01 14:12:33.000000000 +0200
@@ -0,0 +1,20 @@
+#include <asm/udbg.h>
+#include <asm/io.h>
+
+extern u8 real_readb(volatile u8 __iomem  *addr);
+extern void real_writeb(u8 data, volatile u8 __iomem *addr);
+
+static void udbg_xenon_real_putc(char c)
+{
+	if (c == '\n')
+		udbg_xenon_real_putc('\r');
+	while (!(real_readb((void*)0x200ea001018ULL)&0x02));
+	real_writeb(c, (void*)0x200ea001014ULL);
+}
+
+int udbg_init_xenon(void)
+{
+	udbg_putc = udbg_xenon_real_putc;
+
+	return 0;
+}
Index: linux-2.6.21/arch/powerpc/platforms/xenon/Makefile
===================================================================
--- linux-2.6.21.orig/arch/powerpc/platforms/xenon/Makefile	2007-05-01 14:12:33.000000000 +0200
+++ linux-2.6.21/arch/powerpc/platforms/xenon/Makefile	2007-05-01 14:12:33.000000000 +0200
@@ -1,4 +1,4 @@
-obj-$(CONFIG_PPC_XENON)		+= setup.o interrupt.o pci.o
+obj-$(CONFIG_PPC_XENON)		+= setup.o interrupt.o pci.o udbg.o
 ifeq ($(CONFIG_SMP),y)
 obj-$(CONFIG_PPC_XENON)		+= smp.o
 endif