1 files changed, 125 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/udbg.c b/arch/powerpc/kernel/udbg.c
new file mode 100644
index 000000000000..0d878e72fc44
--- /dev/null
+++ b/arch/powerpc/kernel/udbg.c
@@ -0,0 +1,125 @@
+/*
+ * polling mode stateless debugging stuff, originally for NS16550 Serial Ports
+ *
+ * c 2001 PPC 64 Team, IBM Corp
+ *
+ *      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 <stdarg.h>
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/console.h>
+#include <asm/processor.h>
+
+void (*udbg_putc)(unsigned char c);
+unsigned char (*udbg_getc)(void);
+int (*udbg_getc_poll)(void);
+
+/* udbg library, used by xmon et al */
+void udbg_puts(const char *s)
+{
+        if (udbg_putc) {
+                char c;
+
+                if (s && *s != '\0') {
+                        while ((c = *s++) != '\0')
+                                udbg_putc(c);
+                }
+        }
+#if 0
+        else {
+                printk("%s", s);
+        }
+#endif
+}
+
+int udbg_write(const char *s, int n)
+{
+        int remain = n;
+        char c;
+
+        if (!udbg_putc)
+                return 0;
+
+        if (s && *s != '\0') {
+                while (((c = *s++) != '\0') && (remain-- > 0)) {
+                        udbg_putc(c);
+                }
+        }
+
+        return n - remain;
+}
+
+int udbg_read(char *buf, int buflen)
+{
+        char c, *p = buf;
+        int i;
+
+        if (!udbg_getc)
+                return 0;
+
+        for (i = 0; i < buflen; ++i) {
+                do {
+                        c = udbg_getc();
+                } while (c == 0x11 || c == 0x13);
+                if (c == 0)
+                        break;
+                *p++ = c;
+        }
+
+        return i;
+}
+
+#define UDBG_BUFSIZE 256
+void udbg_printf(const char *fmt, ...)
+{
+        unsigned char buf[UDBG_BUFSIZE];
+        va_list args;
+
+        va_start(args, fmt);
+        vsnprintf(buf, UDBG_BUFSIZE, fmt, args);
+        udbg_puts(buf);
+        va_end(args);
+}
+
+/*
+ * Early boot console based on udbg
+ */
+static void udbg_console_write(struct console *con, const char *s,
+                unsigned int n)
+{
+        udbg_write(s, n);
+}
+
+static struct console udbg_console = {
+        .name   = "udbg",
+        .write  = udbg_console_write,
+        .flags  = CON_PRINTBUFFER,
+        .index  = -1,
+};
+
+static int early_console_initialized;
+
+void __init disable_early_printk(void)
+{
+        if (!early_console_initialized)
+                return;
+        unregister_console(&udbg_console);
+        early_console_initialized = 0;
+}
+
+/* called by setup_system */
+void register_early_udbg_console(void)
+{
+        early_console_initialized = 1;
+        register_console(&udbg_console);
+}
+
+#if 0   /* if you want to use this as a regular output console */
+console_initcall(register_udbg_console);
+#endif