[PATCH] ARM: 2745/1: Fix IXP4xx debug macros

Patch from Deepak Saxena

Current IXP4xx debug macros do not work in the small window between
the MMU being enabled and the call to map_io() b/c the standard
peripheral mapping is not properly setup for use with the low-level
debug code. This patch creates a new section-aligned mapping for the
UART specifically for use with the debug macros.

Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-ixp4xx/common.c

@@ -141,7 +141,15 @@ static struct map_desc ixp4xx_io_desc[] __initdata = {
 		.physical	= IXP4XX_PCI_CFG_BASE_PHYS,
 		.length		= IXP4XX_PCI_CFG_REGION_SIZE,
 		.type		= MT_DEVICE
+	},
+#ifdef CONFIG_DEBUG_LL
+	{	/* Debug UART mapping */
+		.virtual	= IXP4XX_DEBUG_UART_BASE_VIRT,
+		.physical	= IXP4XX_DEBUG_UART_BASE_PHYS,
+		.length		= IXP4XX_DEBUG_UART_REGION_SIZE,
+		.type		= MT_DEVICE
 	}
+#endif
 };
 
 void __init ixp4xx_map_io(void)

include/asm-arm/arch-ixp4xx/debug-macro.S

@@ -14,6 +14,7 @@
                 mrc     p15, 0, \rx, c1, c0
                 tst     \rx, #1                 @ MMU enabled?
                 moveq   \rx, #0xc8000000
+		orrne	\rx, \rx, #0x00b00000
                 movne   \rx, #0xff000000
                 add     \rx,\rx,#3              @ Uart regs are at off set of 3 if
 						@ byte writes used - Big Endian.

include/asm-arm/arch-ixp4xx/ixp4xx-regs.h

@@ -69,6 +69,16 @@
 #define IXP4XX_PERIPHERAL_BASE_VIRT	(0xFFBF2000)
 #define IXP4XX_PERIPHERAL_REGION_SIZE	(0x0000C000)
 
+/*
+ * Debug UART
+ *
+ * This is basically a remap of UART1 into a region that is section
+ * aligned so that it * can be used with the low-level debug code.
+ */
+#define	IXP4XX_DEBUG_UART_BASE_PHYS	(0xC8000000)
+#define	IXP4XX_DEBUG_UART_BASE_VIRT	(0xffb00000)
+#define	IXP4XX_DEBUG_UART_REGION_SIZE	(0x00001000)
+
 #define IXP4XX_EXP_CS0_OFFSET	0x00
 #define IXP4XX_EXP_CS1_OFFSET   0x04
 #define IXP4XX_EXP_CS2_OFFSET   0x08