v4.19.13 snapshot.
diff --git a/arch/mips/boot/compressed/uart-alchemy.c b/arch/mips/boot/compressed/uart-alchemy.c
new file mode 100644
index 0000000..8ec6301
--- /dev/null
+++ b/arch/mips/boot/compressed/uart-alchemy.c
@@ -0,0 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <asm/mach-au1x00/au1000.h>
+
+void putc(char c)
+{
+	alchemy_uart_putchar(AU1000_UART0_PHYS_ADDR, c);
+}