MIPS: lantiq: fix early printk

The code was using a 32bit write operations in the early_printk code. This
resulted in 3 zero bytes also being written to the serial port. This patch
changes the memory access to 8bit.

Signed-off-by: Thomas Langer <thomas.langer@lantiq.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3721/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/mach-lantiq/xway/lantiq_soc.h

@@ -34,6 +34,12 @@
 #define LTQ_ASC1_BASE_ADDR	0x1E100C00
 #define LTQ_ASC_SIZE		0x400
 
+/*
+ * during early_printk no ioremap is possible
+ * lets use KSEG1 instead
+ */
+#define LTQ_EARLY_ASC		KSEG1ADDR(LTQ_ASC1_BASE_ADDR)
+
 /* RCU - reset control unit */
 #define LTQ_RCU_BASE_ADDR	0x1F203000
 #define LTQ_RCU_SIZE		0x1000

arch/mips/lantiq/early_printk.c

@@ -6,17 +6,16 @@
  *  Copyright (C) 2010 John Crispin <blogic@openwrt.org>
  */
 
-#include <linux/init.h>
 #include <linux/cpu.h>
-
-#include <lantiq.h>
 #include <lantiq_soc.h>
 
-/* no ioremap possible at this early stage, lets use KSEG1 instead  */
-#define LTQ_ASC_BASE	KSEG1ADDR(LTQ_ASC1_BASE_ADDR)
 #define ASC_BUF		1024
-#define LTQ_ASC_FSTAT	((u32 *)(LTQ_ASC_BASE + 0x0048))
-#define LTQ_ASC_TBUF	((u32 *)(LTQ_ASC_BASE + 0x0020))
+#define LTQ_ASC_FSTAT	((u32 *)(LTQ_EARLY_ASC + 0x0048))
+#ifdef __BIG_ENDIAN
+#define LTQ_ASC_TBUF	((u32 *)(LTQ_EARLY_ASC + 0x0020 + 3))
+#else
+#define LTQ_ASC_TBUF	((u32 *)(LTQ_EARLY_ASC + 0x0020))
+#endif
 #define TXMASK		0x3F00
 #define TXOFFSET	8
 
@@ -27,7 +26,7 @@ void prom_putchar(char c)
 	local_irq_save(flags);
 	do { } while ((ltq_r32(LTQ_ASC_FSTAT) & TXMASK) >> TXOFFSET);
 	if (c == '\n')
-		ltq_w32('\r', LTQ_ASC_TBUF);
-	ltq_w32(c, LTQ_ASC_TBUF);
+		ltq_w8('\r', LTQ_ASC_TBUF);
+	ltq_w8(c, LTQ_ASC_TBUF);
 	local_irq_restore(flags);
 }