[POWERPC] Add non-OF serial console support

Add serial console support for non-OF systems.  There is a generic serial
console layer which calls a serial console driver.  Included is the serial
console driver for the ns16550 class of uarts.  Necessary support routines
are added as well.

Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 74 insertions, 0 deletions

diff --git a/arch/powerpc/boot/ns16550.c b/arch/powerpc/boot/ns16550.c
new file mode 100644
index 00000000000..1ffe72e35cd
--- /dev/null
+++ b/arch/powerpc/boot/ns16550.c
@@ -0,0 +1,74 @@
+/*
+ * 16550 serial console support.
+ *
+ * Original copied from <file:arch/ppc/boot/common/ns16550.c>
+ * (which had no copyright)
+ * Modifications: 2006 (c) MontaVista Software, Inc.
+ *
+ * Modified by: Mark A. Greer <mgreer@mvista.com>
+ */
+#include <stdarg.h>
+#include <stddef.h>
+#include "types.h"
+#include "string.h"
+#include "stdio.h"
+#include "io.h"
+#include "ops.h"
+
+#define UART_DLL	0	/* Out: Divisor Latch Low */
+#define UART_DLM	1	/* Out: Divisor Latch High */
+#define UART_FCR	2	/* Out: FIFO Control Register */
+#define UART_LCR	3	/* Out: Line Control Register */
+#define UART_MCR	4	/* Out: Modem Control Register */
+#define UART_LSR	5	/* In:  Line Status Register */
+#define UART_LSR_THRE	0x20	/* Transmit-hold-register empty */
+#define UART_LSR_DR	0x01	/* Receiver data ready */
+#define UART_MSR	6	/* In:  Modem Status Register */
+#define UART_SCR	7	/* I/O: Scratch Register */
+
+static unsigned char *reg_base;
+static u32 reg_shift;
+
+static int ns16550_open(void)
+{
+	out_8(reg_base + (UART_FCR << reg_shift), 0x06);
+	return 0;
+}
+
+static void ns16550_putc(unsigned char c)
+{
+	while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_THRE) == 0);
+	out_8(reg_base, c);
+}
+
+static unsigned char ns16550_getc(void)
+{
+	while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) == 0);
+	return in_8(reg_base);
+}
+
+static u8 ns16550_tstc(void)
+{
+	return ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) != 0);
+}
+
+int ns16550_console_init(void *devp, struct serial_console_data *scdp)
+{
+	int n;
+
+	n = getprop(devp, "virtual-reg", &reg_base, sizeof(reg_base));
+	if (n != sizeof(reg_base))
+		return -1;
+
+	n = getprop(devp, "reg-shift", &reg_shift, sizeof(reg_shift));
+	if (n != sizeof(reg_shift))
+		reg_shift = 0;
+
+	scdp->open = ns16550_open;
+	scdp->putc = ns16550_putc;
+	scdp->getc = ns16550_getc;
+	scdp->tstc = ns16550_tstc;
+	scdp->close = NULL;
+
+	return 0;
+}