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-rw-r--r--arch/sh/kernel/early_printk.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/sh/kernel/early_printk.c b/arch/sh/kernel/early_printk.c
new file mode 100644
index 000000000000..1378db375e17
--- /dev/null
+++ b/arch/sh/kernel/early_printk.c
@@ -0,0 +1,137 @@
+/*
+ * arch/sh/kernel/early_printk.c
+ *
+ * Copyright (C) 1999, 2000 Niibe Yutaka
+ * Copyright (C) 2002 M. R. Brown
+ * Copyright (C) 2004 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/console.h>
+#include <linux/tty.h>
+#include <linux/init.h>
+#include <asm/io.h>
+
+#ifdef CONFIG_SH_STANDARD_BIOS
+#include <asm/sh_bios.h>
+
+/*
+ * 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 early_console = {
+ .name = "bios",
+ .write = sh_console_write,
+ .setup = sh_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+};
+#endif
+
+#ifdef CONFIG_EARLY_SCIF_CONSOLE
+#define SCIF_REG 0xffe80000
+
+static void scif_sercon_putc(int c)
+{
+ while (!(ctrl_inw(SCIF_REG + 0x10) & 0x20)) ;
+
+ ctrl_outb(c, SCIF_REG + 12);
+ ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0x9f), SCIF_REG + 0x10);
+
+ if (c == '\n')
+ scif_sercon_putc('\r');
+}
+
+static void scif_sercon_flush(void)
+{
+ ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0xbf), SCIF_REG + 0x10);
+
+ while (!(ctrl_inw(SCIF_REG + 0x10) & 0x40)) ;
+
+ ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0xbf), SCIF_REG + 0x10);
+}
+
+static void scif_sercon_write(struct console *con, const char *s, unsigned count)
+{
+ while (count-- > 0)
+ scif_sercon_putc(*s++);
+
+ scif_sercon_flush();
+}
+
+static int __init scif_sercon_setup(struct console *con, char *options)
+{
+ con->cflag = CREAD | HUPCL | CLOCAL | B115200 | CS8;
+
+ return 0;
+}
+
+static struct console early_console = {
+ .name = "sercon",
+ .write = scif_sercon_write,
+ .setup = scif_sercon_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+};
+
+void scif_sercon_init(int baud)
+{
+ ctrl_outw(0, SCIF_REG + 8);
+ ctrl_outw(0, SCIF_REG);
+
+ /* Set baud rate */
+ ctrl_outb((CONFIG_SH_PCLK_FREQ + 16 * baud) /
+ (32 * baud) - 1, SCIF_REG + 4);
+
+ ctrl_outw(12, SCIF_REG + 24);
+ ctrl_outw(8, SCIF_REG + 24);
+ ctrl_outw(0, SCIF_REG + 32);
+ ctrl_outw(0x60, SCIF_REG + 16);
+ ctrl_outw(0, SCIF_REG + 36);
+ ctrl_outw(0x30, SCIF_REG + 8);
+}
+#endif
+
+void __init enable_early_printk(void)
+{
+#ifdef CONFIG_EARLY_SCIF_CONSOLE
+ scif_sercon_init(115200);
+#endif
+ register_console(&early_console);
+}
+
+void disable_early_printk(void)
+{
+ unregister_console(&early_console);
+}
+