socfpga: map uart into virtual address space so that early_printk() works

Early printk code needs UART to be mapped early during
boot. early_printk() is left there during the start-up; it is useful
as our emulators are fairly slow.
Signed-off-by: Pavel Machek <pavel@denx.de>
Acked-by: Dinh Nguyen <dinguyen@altera.com>
[olof: removed redundant newlines]
Signed-off-by: Olof Johansson <olof@lixom.net>

arch/arm/mach-socfpga/socfpga.c

@@ -37,6 +37,13 @@ static struct map_desc scu_io_desc __initdata = {
 	.type		= MT_DEVICE,
 };
 
+static struct map_desc uart_io_desc __initdata = {
+	.virtual	= 0xfec02000,
+	.pfn		= __phys_to_pfn(0xffc02000),
+	.length		= SZ_8K,
+	.type		= MT_DEVICE,
+};
+
 static void __init socfpga_scu_map_io(void)
 {
 	unsigned long base;
@@ -51,6 +58,8 @@ static void __init socfpga_scu_map_io(void)
 static void __init socfpga_map_io(void)
 {
 	socfpga_scu_map_io();
+	iotable_init(&uart_io_desc, 1);
+	early_printk("Early printk initialized\n");
 }
 
 const static struct of_device_id irq_match[] = {