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authorMark A. Greer <mgreer@mvista.com>2006-10-16 13:52:09 -0700
committerPaul Mackerras <paulus@samba.org>2006-10-23 12:49:19 +1000
commit0c176fa80fdfa9b4e0753e37223b056994c818d2 (patch)
treeaa45e2bba6f57ac1e85e81f2482667c0873fefa4 /arch/powerpc/boot/ns16550.c
parent6fb4efc68f5c0e095153510dcfa8b54a42e914ba (diff)
downloadop-kernel-dev-0c176fa80fdfa9b4e0753e37223b056994c818d2.zip
op-kernel-dev-0c176fa80fdfa9b4e0753e37223b056994c818d2.tar.gz
[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>
Diffstat (limited to 'arch/powerpc/boot/ns16550.c')
-rw-r--r--arch/powerpc/boot/ns16550.c74
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 0000000..1ffe72e
--- /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;
+}
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