1 files changed, 134 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/wsp/h8.c b/arch/powerpc/platforms/wsp/h8.c
new file mode 100644
index 000000000000..d18e6cc19df3
--- /dev/null
+++ b/arch/powerpc/platforms/wsp/h8.c
@@ -0,0 +1,134 @@
+/*
+ * Copyright 2008-2011, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/io.h>
+
+#include "wsp.h"
+
+/*
+ * The UART connection to the H8 is over ttyS1 which is just a 16550.
+ * We assume that FW has it setup right and no one messes with it.
+ */
+
+
+static u8 __iomem *h8;
+
+#define RBR 0		/* Receiver Buffer Register */
+#define THR 0		/* Transmitter Holding Register */
+#define LSR 5		/* Line Status Register */
+#define LSR_DR 0x01	/* LSR value for Data-Ready */
+#define LSR_THRE 0x20	/* LSR value for Transmitter-Holding-Register-Empty */
+static void wsp_h8_putc(int c)
+{
+	u8 lsr;
+
+	do {
+		lsr = readb(h8 + LSR);
+	} while ((lsr & LSR_THRE) != LSR_THRE);
+	writeb(c, h8 + THR);
+}
+
+static int wsp_h8_getc(void)
+{
+	u8 lsr;
+
+	do {
+		lsr = readb(h8 + LSR);
+	} while ((lsr & LSR_DR) != LSR_DR);
+
+	return readb(h8 + RBR);
+}
+
+static void wsp_h8_puts(const char *s, int sz)
+{
+	int i;
+
+	for (i = 0; i < sz; i++) {
+		wsp_h8_putc(s[i]);
+
+		/* no flow control so wait for echo */
+		wsp_h8_getc();
+	}
+	wsp_h8_putc('\r');
+	wsp_h8_putc('\n');
+}
+
+static void wsp_h8_terminal_cmd(const char *cmd, int sz)
+{
+	hard_irq_disable();
+	wsp_h8_puts(cmd, sz);
+	/* should never return, but just in case */
+	for (;;)
+		continue;
+}
+
+
+void wsp_h8_restart(char *cmd)
+{
+	static const char restart[] = "warm-reset";
+
+	(void)cmd;
+	wsp_h8_terminal_cmd(restart, sizeof(restart) - 1);
+}
+
+void wsp_h8_power_off(void)
+{
+	static const char off[] = "power-off";
+
+	wsp_h8_terminal_cmd(off, sizeof(off) - 1);
+}
+
+static void __iomem *wsp_h8_getaddr(void)
+{
+	struct device_node *aliases;
+	struct device_node *uart;
+	struct property *path;
+	void __iomem *va = NULL;
+
+	/*
+	 * there is nothing in the devtree to tell us which is mapped
+	 * to the H8, but se know it is the second serial port.
+	 */
+
+	aliases = of_find_node_by_path("/aliases");
+	if (aliases == NULL)
+		return NULL;
+
+	path = of_find_property(aliases, "serial1", NULL);
+	if (path == NULL)
+		goto out;
+
+	uart = of_find_node_by_path(path->value);
+	if (uart == NULL)
+		goto out;
+
+	va = of_iomap(uart, 0);
+
+	/* remove it so no one messes with it */
+	of_detach_node(uart);
+	of_node_put(uart);
+
+out:
+	of_node_put(aliases);
+
+	return va;
+}
+
+void __init wsp_setup_h8(void)
+{
+	h8 = wsp_h8_getaddr();
+
+	/* Devtree change? lets hard map it anyway */
+	if (h8 == NULL) {
+		pr_warn("UART to H8 could not be found");
+		h8 = ioremap(0xffc0008000ULL, 0x100);
+	}
+}