[MIPS] Add early console for Cobalt.

    
Signed-off-by: Peter Horton <pdh@colonel-panic.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

6 files changed, 60 insertions, 8 deletions

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 3a0f89d2c8dc..9d1e78f9c060 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -790,6 +790,7 @@ source "arch/mips/tx4927/Kconfig"
 source "arch/mips/tx4938/Kconfig"
 source "arch/mips/vr41xx/Kconfig"
 source "arch/mips/philips/pnx8550/common/Kconfig"
+source "arch/mips/cobalt/Kconfig"
 
 endmenu
 
diff --git a/arch/mips/cobalt/Kconfig b/arch/mips/cobalt/Kconfig
new file mode 100644
index 000000000000..7c42b088d16c
--- /dev/null
+++ b/arch/mips/cobalt/Kconfig
@@ -0,0 +1,7 @@
+config EARLY_PRINTK
+        bool "Early console support"
+        depends on MIPS_COBALT
+        help
+          Provide early console support by direct access to the
+          on board UART. The UART must have been previously
+          initialised by the boot loader.
diff --git a/arch/mips/cobalt/Makefile b/arch/mips/cobalt/Makefile
index 3b6b7579d1de..720e757b2b64 100644
--- a/arch/mips/cobalt/Makefile
+++ b/arch/mips/cobalt/Makefile
@@ -4,4 +4,6 @@
 
 obj-y    := irq.o int-handler.o reset.o setup.o
 
+obj-$(CONFIG_EARLY_PRINTK)      += console.o
+
 EXTRA_AFLAGS := $(CFLAGS)
diff --git a/arch/mips/cobalt/console.c b/arch/mips/cobalt/console.c
new file mode 100644
index 000000000000..45c2d27c7564
--- /dev/null
+++ b/arch/mips/cobalt/console.c
@@ -0,0 +1,43 @@
+/*
+ * (C) P. Horton 2006
+ */
+
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/console.h>
+#include <linux/serial_reg.h>
+#include <asm/addrspace.h>
+#include <asm/mach-cobalt/cobalt.h>
+
+static void putchar(int c)
+{
+        if(c == '\n')
+                putchar('\r');
+
+        while(!(COBALT_UART[UART_LSR] & UART_LSR_THRE))
+                ;
+
+        COBALT_UART[UART_TX] = c;
+}
+
+static void cons_write(struct console *c, const char *s, unsigned n)
+{
+        while(n-- && *s)
+                putchar(*s++);
+}
+
+static struct console cons_info =
+{
+        .name   = "uart",
+        .write  = cons_write,
+        .flags  = CON_PRINTBUFFER | CON_BOOT,
+        .index  = -1,
+};
+
+void __init cobalt_early_console(void)
+{
+        register_console(&cons_info);
+
+        printk("Cobalt: early console registered\n");
+}
diff --git a/arch/mips/cobalt/setup.c b/arch/mips/cobalt/setup.c
index b9713a723053..4f9ea1210023 100644
--- a/arch/mips/cobalt/setup.c
+++ b/arch/mips/cobalt/setup.c
@@ -31,6 +31,7 @@
 extern void cobalt_machine_restart(char *command);
 extern void cobalt_machine_halt(void);
 extern void cobalt_machine_power_off(void);
+extern void cobalt_early_console(void);
 
 int cobalt_board_id;
 
@@ -109,14 +110,6 @@ void __init plat_setup(void)
         /* I/O port resource must include UART and LCD/buttons */
         ioport_resource.end = 0x0fffffff;
 
-        /*
-         * This is a prom style console. We just poke at the
-         *  UART to make it talk.
-         * Only use this console if you really screw up and can't
-         *  get to the stage of setting up a real serial console.
-         */
-        /*ns16550_setup_console();*/
-
         /* request I/O space for devices used on all i[345]86 PCs */
         for (i = 0; i < COBALT_IO_RESOURCES; i++)
                 request_resource(&ioport_resource, cobalt_io_resources + i);
@@ -136,6 +129,10 @@ void __init plat_setup(void)
 #ifdef CONFIG_SERIAL_8250
         if (cobalt_board_id > COBALT_BRD_ID_RAQ1) {
 
+#ifdef CONFIG_EARLY_PRINTK
+                cobalt_early_console();
+#endif
+
                 uart.line       = 0;
                 uart.type       = PORT_UNKNOWN;
                 uart.uartclk    = 18432000;
diff --git a/include/asm-mips/mach-cobalt/cobalt.h b/include/asm-mips/mach-cobalt/cobalt.h
index 78e1df2095fb..b3c5ecbec03c 100644
--- a/include/asm-mips/mach-cobalt/cobalt.h
+++ b/include/asm-mips/mach-cobalt/cobalt.h
@@ -113,4 +113,6 @@ do {									\
 # define COBALT_KEY_SELECT      (1 << 7)
 # define COBALT_KEY_MASK        0xfe
 
+#define COBALT_UART             ((volatile unsigned char *) CKSEG1ADDR(0x1c800000))
+
 #endif /* __ASM_COBALT_H */