or1k: add basic qemu support

Kernel boots, userland not.

target/config/Config.in.kernel

@@ -84,3 +84,4 @@ config ADK_TARGET_KERNEL_MINICONFIG
 	default "qemu-m68k-q800" if ADK_TARGET_QEMU_M68K_Q800
 	default "imgtec-ci20" if ADK_TARGET_SYSTEM_IMGTEC_CI20
 	default "qemu-metag" if ADK_TARGET_SYSTEM_QEMU_METAG
+	default "qemu-or1k" if ADK_TARGET_SYSTEM_QEMU_OR1K

target/linux/config/Config.in.serial

@@ -48,13 +48,16 @@ config ADK_KERNEL_SERIAL_ETRAXFS
 
 config ADK_KERNEL_SERIAL_8250
 	bool "8250 serial driver"
-	select ADK_KERNEL_SERIAL_OF_PLATFORM if ADK_TARGET_SYSTEM_XILINX_KINTEX7
+	select ADK_KERNEL_SERIAL_OF_PLATFORM if ADK_TARGET_SYSTEM_XILINX_KINTEX7 \
+						|| ADK_TARGET_SYSTEM_QEMU_OR1K
 	select ADK_KERNEL_SERIAL_8250_PNP if ADK_TARGET_SYSTEM_PCENGINES_APU
 	select ADK_KERNEL_SERIAL_8250_CONSOLE
 	depends on ADK_TARGET_SYSTEM_XILINX_KINTEX7 \
-		|| ADK_TARGET_SYSTEM_PCENGINES_APU
+		|| ADK_TARGET_SYSTEM_PCENGINES_APU \
+		|| ADK_TARGET_SYSTEM_QEMU_OR1K
 	default y if ADK_TARGET_SYSTEM_XILINX_KINTEX7
 	default y if ADK_TARGET_SYSTEM_PCENGINES_APU
+	default y if ADK_TARGET_SYSTEM_QEMU_OR1K
 	default n
 	help
 	  Serial driver for 8250 UART chip.

target/or1k/Makefile

@@ -7,12 +7,17 @@ include $(ADK_TOPDIR)/mk/image.mk
 
 KERNEL:=$(LINUX_DIR)/vmlinux
 OSTRIP:=-R .reginfo -R .notes -R .note -R .comment -R .mdebug -R .note.gnu.build-id
+QEMU_ARGS:=-nographic
 
 # target helper text
 ifeq ($(ADK_TARGET_FS),initramfs)
 targethelp:
 	@echo 'The kernel file is: $(FW_DIR)/${TARGET_KERNEL}'
 	@echo 'The initramfs image is: ${FW_DIR}/${INITRAMFS}'
+ifeq ($(ADK_TARGET_QEMU),y)
+	@echo "Start qemu with following command line:"
+	@echo 'qemu-system-or32 ${QEMU_ARGS} -kernel $(FW_DIR)/$(TARGET_KERNEL) -initrd ${FW_DIR}/${INITRAMFS}'
+endif
 endif
 ifeq ($(ADK_TARGET_FS),initramfsarchive)
 targethelp:
@@ -22,6 +27,10 @@ endif
 ifeq ($(ADK_TARGET_FS),initramfspiggyback)
 targethelp:
 	@echo 'The kernel+initramfs file is: $(FW_DIR)/${TARGET_KERNEL}'
+ifeq ($(ADK_TARGET_QEMU),y)
+	@echo "Start qemu with following command line:"
+	@echo 'qemu-system-or32 ${QEMU_ARGS} -kernel $(FW_DIR)/$(TARGET_KERNEL)'
+endif
 endif
 
 kernel-strip:

target/or1k/kernel/qemu-or1k

@@ -0,0 +1,2 @@
+CONFIG_OPENRISC=Y
+CONFIG_OPENRISC_BUILTIN_DTB="or1ksim"

target/or1k/patches/4.1.6/ld-or1k.patch

@@ -0,0 +1,12 @@
+diff -Nur linux-4.1.6.orig/arch/openrisc/kernel/vmlinux.lds.S linux-4.1.6/arch/openrisc/kernel/vmlinux.lds.S
+--- linux-4.1.6.orig/arch/openrisc/kernel/vmlinux.lds.S	2015-08-17 05:52:51.000000000 +0200
++++ linux-4.1.6/arch/openrisc/kernel/vmlinux.lds.S	2015-09-01 22:02:13.224692884 +0200
+@@ -30,7 +30,7 @@
+ #include <asm/cache.h>
+ #include <asm-generic/vmlinux.lds.h>
+ 
+-OUTPUT_FORMAT("elf32-or32", "elf32-or32", "elf32-or32")
++OUTPUT_FORMAT("elf32-or1k", "elf32-or1k", "elf32-or1k")
+ jiffies = jiffies_64 + 4;
+ 
+ SECTIONS

target/or1k/systems/qemu-or1k

@@ -0,0 +1,6 @@
+config ADK_TARGET_SYSTEM_QEMU_OR1K
+	bool "Qemu Emulator"
+	select ADK_TARGET_QEMU
+	help
+	  Qemu Emulator for OR1K architecture.
+