1 files changed, 109 insertions, 0 deletions
diff --git a/arch/tile/kernel/early_printk.c b/arch/tile/kernel/early_printk.c
new file mode 100644
index 000000000000..2c54fd43a8a0
--- /dev/null
+++ b/arch/tile/kernel/early_printk.c
@@ -0,0 +1,109 @@
+/*
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ *   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, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <asm/setup.h>
+#include <hv/hypervisor.h>
+
+static void early_hv_write(struct console *con, const char *s, unsigned n)
+{
+	hv_console_write((HV_VirtAddr) s, n);
+}
+
+static struct console early_hv_console = {
+	.name =		"earlyhv",
+	.write =	early_hv_write,
+	.flags =	CON_PRINTBUFFER,
+	.index =	-1,
+};
+
+/* Direct interface for emergencies */
+static struct console *early_console = &early_hv_console;
+static int early_console_initialized;
+static int early_console_complete;
+
+static void early_vprintk(const char *fmt, va_list ap)
+{
+	char buf[512];
+	int n = vscnprintf(buf, sizeof(buf), fmt, ap);
+	early_console->write(early_console, buf, n);
+}
+
+void early_printk(const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	early_vprintk(fmt, ap);
+	va_end(ap);
+}
+
+void early_panic(const char *fmt, ...)
+{
+	va_list ap;
+	raw_local_irq_disable_all();
+	va_start(ap, fmt);
+	early_printk("Kernel panic - not syncing: ");
+	early_vprintk(fmt, ap);
+	early_console->write(early_console, "\n", 1);
+	va_end(ap);
+	dump_stack();
+	hv_halt();
+}
+
+static int __initdata keep_early;
+
+static int __init setup_early_printk(char *str)
+{
+	if (early_console_initialized)
+		return 1;
+
+	if (str != NULL && strncmp(str, "keep", 4) == 0)
+		keep_early = 1;
+
+	early_console = &early_hv_console;
+	early_console_initialized = 1;
+	register_console(early_console);
+
+	return 0;
+}
+
+void __init disable_early_printk(void)
+{
+	early_console_complete = 1;
+	if (!early_console_initialized || !early_console)
+		return;
+	if (!keep_early) {
+		early_printk("disabling early console\n");
+		unregister_console(early_console);
+		early_console_initialized = 0;
+	} else {
+		early_printk("keeping early console\n");
+	}
+}
+
+void warn_early_printk(void)
+{
+	if (early_console_complete || early_console_initialized)
+		return;
+	early_printk("\
+Machine shutting down before console output is fully initialized.\n\
+You may wish to reboot and add the option 'earlyprintk' to your\n\
+boot command line to see any diagnostic early console output.\n\
+");
+}
+
+early_param("earlyprintk", setup_early_printk);