1 files changed, 122 insertions, 7 deletions

diff --git a/arch/sh/kernel/sh_bios.c b/arch/sh/kernel/sh_bios.c
index c852f7805728..47475cca068a 100644
--- a/arch/sh/kernel/sh_bios.c
+++ b/arch/sh/kernel/sh_bios.c
@@ -1,19 +1,30 @@
 /*
- *  linux/arch/sh/kernel/sh_bios.c
  *  C interface for trapping into the standard LinuxSH BIOS.
  *
  *  Copyright (C) 2000 Greg Banks, Mitch Davis
+ *  Copyright (C) 1999, 2000  Niibe Yutaka
+ *  Copyright (C) 2002  M. R. Brown
+ *  Copyright (C) 2004 - 2010  Paul Mundt
  *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
  */
 #include <linux/module.h>
+#include <linux/console.h>
+#include <linux/tty.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/delay.h>
 #include <asm/sh_bios.h>
 
 #define BIOS_CALL_CONSOLE_WRITE         0
 #define BIOS_CALL_ETH_NODE_ADDR         10
 #define BIOS_CALL_SHUTDOWN              11
-#define BIOS_CALL_CHAR_OUT              0x1f    /* TODO: hack */
 #define BIOS_CALL_GDB_DETACH            0xff
 
+void *gdb_vbr_vector = NULL;
+
 static inline long sh_bios_call(long func, long arg0, long arg1, long arg2,
                                     long arg3)
 {
@@ -23,6 +34,9 @@ static inline long sh_bios_call(long func, long arg0, long arg1, long arg2,
         register long r6 __asm__("r6") = arg2;
         register long r7 __asm__("r7") = arg3;
 
+        if (!gdb_vbr_vector)
+                return -ENOSYS;
+
         __asm__ __volatile__("trapa     #0x3f":"=z"(r0)
                              :"0"(r0), "r"(r4), "r"(r5), "r"(r6), "r"(r7)
                              :"memory");
@@ -34,11 +48,6 @@ void sh_bios_console_write(const char *buf, unsigned int len)
         sh_bios_call(BIOS_CALL_CONSOLE_WRITE, (long)buf, (long)len, 0, 0);
 }
 
-void sh_bios_char_out(char ch)
-{
-        sh_bios_call(BIOS_CALL_CHAR_OUT, ch, 0, 0, 0);
-}
-
 void sh_bios_gdb_detach(void)
 {
         sh_bios_call(BIOS_CALL_GDB_DETACH, 0, 0, 0, 0);
@@ -55,3 +64,109 @@ void sh_bios_shutdown(unsigned int how)
 {
         sh_bios_call(BIOS_CALL_SHUTDOWN, how, 0, 0, 0);
 }
+
+/*
+ * Read the old value of the VBR register to initialise the vector
+ * through which debug and BIOS traps are delegated by the Linux trap
+ * handler.
+ */
+void sh_bios_vbr_init(void)
+{
+        unsigned long vbr;
+
+        if (unlikely(gdb_vbr_vector))
+                return;
+
+        __asm__ __volatile__ ("stc vbr, %0" : "=r" (vbr));
+
+        if (vbr) {
+                gdb_vbr_vector = (void *)(vbr + 0x100);
+                printk(KERN_NOTICE "Setting GDB trap vector to %p\n",
+                       gdb_vbr_vector);
+        } else
+                printk(KERN_NOTICE "SH-BIOS not detected\n");
+}
+
+/**
+ * sh_bios_vbr_reload - Re-load the system VBR from the BIOS vector.
+ *
+ * This can be used by save/restore code to reinitialize the system VBR
+ * from the fixed BIOS VBR. A no-op if no BIOS VBR is known.
+ */
+void sh_bios_vbr_reload(void)
+{
+        if (gdb_vbr_vector)
+                __asm__ __volatile__ (
+                        "ldc %0, vbr"
+                        :
+                        : "r" (((unsigned long) gdb_vbr_vector) - 0x100)
+                        : "memory"
+                );
+}
+
+/*
+ *      Print a string through the BIOS
+ */
+static void sh_console_write(struct console *co, const char *s,
+                                 unsigned count)
+{
+        sh_bios_console_write(s, count);
+}
+
+/*
+ *      Setup initial baud/bits/parity. We do two things here:
+ *      - construct a cflag setting for the first rs_open()
+ *      - initialize the serial port
+ *      Return non-zero if we didn't find a serial port.
+ */
+static int __init sh_console_setup(struct console *co, char *options)
+{
+        int     cflag = CREAD | HUPCL | CLOCAL;
+
+        /*
+         *      Now construct a cflag setting.
+         *      TODO: this is a totally bogus cflag, as we have
+         *      no idea what serial settings the BIOS is using, or
+         *      even if its using the serial port at all.
+         */
+        cflag |= B115200 | CS8 | /*no parity*/0;
+
+        co->cflag = cflag;
+
+        return 0;
+}
+
+static struct console bios_console = {
+        .name           = "bios",
+        .write          = sh_console_write,
+        .setup          = sh_console_setup,
+        .flags          = CON_PRINTBUFFER,
+        .index          = -1,
+};
+
+static struct console *early_console;
+
+static int __init setup_early_printk(char *buf)
+{
+        int keep_early = 0;
+
+        if (!buf)
+                return 0;
+
+        if (strstr(buf, "keep"))
+                keep_early = 1;
+
+        if (!strncmp(buf, "bios", 4))
+                early_console = &bios_console;
+
+        if (likely(early_console)) {
+                if (keep_early)
+                        early_console->flags &= ~CON_BOOT;
+                else
+                        early_console->flags |= CON_BOOT;
+                register_console(early_console);
+        }
+
+        return 0;
+}
+early_param("earlyprintk", setup_early_printk);