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authorGrant Likely <grant.likely@secretlab.ca>2010-01-28 14:38:25 -0700
committerGrant Likely <grant.likely@secretlab.ca>2010-01-28 14:38:25 -0700
commit0ada0a73120c28cc432bcdbac061781465c2f48f (patch)
treed17cadd4ea47e25d9e48e7d409a39c84268fbd27 /arch/mips/boot/compressed/uart-16550.c
parent6016a363f6b56b46b24655bcfc0499b715851cf3 (diff)
parent92dcffb916d309aa01778bf8963a6932e4014d07 (diff)
Merge commit 'v2.6.33-rc5' into secretlab/test-devicetree
Diffstat (limited to 'arch/mips/boot/compressed/uart-16550.c')
-rw-r--r--arch/mips/boot/compressed/uart-16550.c43
1 files changed, 43 insertions, 0 deletions
diff --git a/arch/mips/boot/compressed/uart-16550.c b/arch/mips/boot/compressed/uart-16550.c
new file mode 100644
index 00000000000..c9caaf4fbf6
--- /dev/null
+++ b/arch/mips/boot/compressed/uart-16550.c
@@ -0,0 +1,43 @@
+/*
+ * 16550 compatible uart based serial debug support for zboot
+ */
+
+#include <linux/types.h>
+#include <linux/serial_reg.h>
+#include <linux/init.h>
+
+#include <asm/addrspace.h>
+
+#if defined(CONFIG_MACH_LOONGSON) || defined(CONFIG_MIPS_MALTA)
+#define UART_BASE 0x1fd003f8
+#define PORT(offset) (CKSEG1ADDR(UART_BASE) + (offset))
+#endif
+
+#ifdef CONFIG_AR7
+#include <ar7.h>
+#define PORT(offset) (CKSEG1ADDR(AR7_REGS_UART0) + (4 * offset))
+#endif
+
+#ifndef PORT
+#error please define the serial port address for your own machine
+#endif
+
+static inline unsigned int serial_in(int offset)
+{
+ return *((char *)PORT(offset));
+}
+
+static inline void serial_out(int offset, int value)
+{
+ *((char *)PORT(offset)) = value;
+}
+
+void putc(char c)
+{
+ int timeout = 1024;
+
+ while (((serial_in(UART_LSR) & UART_LSR_THRE) == 0) && (timeout-- > 0))
+ ;
+
+ serial_out(UART_TX, c);
+}