MIPS: Enable vmlinuz for JZ4740

This patch adds support for building a compressed kernel for the JZ4740
architecture.

Signed-off-by: Lars-Peter Clausen <[e-mail]>
Signed-off-by: Maarten ter Huurne <[e-mail]>
Cc: Sergei Shtylyov <[e-mail]>
Cc: [e-mail]
Patchwork: https://patchwork.linux-mips.org/patch/3563/
Signed-off-by: Ralf Baechle <[e-mail]>

arch/mips/Kconfig

···
 	select SYS_HAS_CPU_MIPS32_R1
 	select SYS_SUPPORTS_32BIT_KERNEL
 	select SYS_SUPPORTS_LITTLE_ENDIAN
+	select SYS_SUPPORTS_ZBOOT_UART16550
 	select DMA_NONCOHERENT
 	select IRQ_CPU
 	select GENERIC_GPIO

arch/mips/boot/compressed/Makefile

···
 # Calculate the load address of the compressed kernel image
 hostprogs-y := calc_vmlinuz_load_addr
 
+ifeq ($(CONFIG_MACH_JZ4740),y)
+VMLINUZ_LOAD_ADDRESS := 0x80600000
+else
 VMLINUZ_LOAD_ADDRESS = $(shell $(obj)/calc_vmlinuz_load_addr \
 		$(obj)/vmlinux.bin $(VMLINUX_LOAD_ADDRESS))
+endif
 
 vmlinuzobjs-y += $(obj)/piggy.o
 

arch/mips/boot/compressed/uart-16550.c

···
 #define PORT(offset) (CKSEG1ADDR(AR7_REGS_UART0) + (4 * offset))
 #endif
 
+#ifdef CONFIG_MACH_JZ4740
+#define UART0_BASE  0xB0030000
+#define PORT(offset) (UART0_BASE + (4 * offset))
+#endif
+
 #ifndef PORT
 #error please define the serial port address for your own machine
 #endif