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..e44d441e3f3f
--- /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 */
+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);