-----Original Message-----
From: linux-arch-owner@vger.kernel.org [mailto:linux-arch-owner@vger.kernel.org] On Behalf Of Paul Mundt
Sent: Thursday, January 06, 2011 3:56 PM
To: Guan Xuetao
Cc: linux-arch@vger.kernel.org; linux-kernel@vger.kernel.org
Subject: Re: [PATCHv1 01/12] unicore32 core architecture: build infrastructure

On Sun, Dec 26, 2010 at 02:41:58AM +0800, Guan Xuetao wrote:

quoted

diff --git a/arch/unicore32/Kconfig b/arch/unicore32/Kconfig
new file mode 100644
index 0000000..da59420
--- /dev/null
+++ b/arch/unicore32/Kconfig

@@ -0,0 +1,258 @@
+config UNICORE32
+	bool
+	default y
+	select HAVE_MEMBLOCK
+	select HAVE_GENERIC_DMA_COHERENT
+	select HAVE_DMA_ATTRS
+	select HAVE_KERNEL_GZIP
+	select HAVE_KERNEL_BZIP2
+	select HAVE_KERNEL_LZO
+	select HAVE_KERNEL_LZMA
+	select GENERIC_FIND_FIRST_BIT
+	select ARCH_WANT_FRAME_POINTERS

You want to select HAVE_GENERIC_HARDIRQS here.

Yes, changed.

quoted

+config GENERIC_HARDIRQS
+	bool
+	default y
+
+config GENERIC_HARDIRQS_NO__DO_IRQ
+	def_bool y
+

Then you can get rid of these, and source kernel/irq/Kconfig.

Removed, and kernel/irq/Kconfig is included in init/Kconfig, just be ok.

quoted

+# arch/unicore32/Makefile
+#
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
+# This file is subject to the terms and conditions of the GNU General Public
+# License.  See the file "COPYING" in the main directory of this archive
+# for more details.
+#
+# Copyright (C) 2002~2010 by Guan Xue-tao
+LOCALVERSION	:= -uc32
+
+CROSS_COMPILE	:= /usr/unicore/gnu-toolchain-unicore/uc4/bin/unicore32-linux-
+

This isn't terribly portable. You can elect to tie in cc-cross-prefix
like other architectures, or just drop it entirely and store it in your
.config (see the top-level Makefile for generic CROSS_COMPILE handling
options).

quoted

+INSTALL_MOD_PATH := $(obj)/usr
+

This and the LOCALVERSION specifications are pretty nasty surprises for
users. This is all handled generically for a reason, so please kill off
of this off.

quoted

+LDFLAGS_vmlinux	:=-p --no-undefined -X
+
+OBJCOPYFLAGS	:=-O binary -R .note -R .note.gnu.build-id -R .comment -S
+GZFLAGS		:=-9
+#KBUILD_CFLAGS	+=-pipe
+# Explicitly specifiy 32-bit UniCore ISA:
+KBUILD_CFLAGS	+=$(call cc-option,-municore,)
+
+# Never generate .eh_frame
+KBUILD_CFLAGS	+= $(call cc-option,-fno-dwarf2-cfi-asm)
+
+ifeq ($(CONFIG_FRAME_POINTER),y)
+KBUILD_CFLAGS	+=-fno-omit-frame-pointer -mno-sched-prolog
+endif
+

-fno-omit-frame-pointer is handled generically, so there is no need for
it here.

quoted

+KBUILD_CPPFLAGS	+= -mlittle-endian
+AS		+= -EL
+LD		+= -EL
+

No. If you need to set AS and LD flags for endianness, then do so
explicitly. See how every other architecture is doing this. You may also
wish to read through Documentation/kbuild/makefiles.txt carefully.

quoted

+comma = ,
+

This is unused?

quoted

+# Need -Uunicore32 for gcc < 3.x
+# delete -mstructure-size-boundary=32, and default being 8
+# delete -funsigned-char, and default being signed-char
+KBUILD_CFLAGS	+=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,)) -msoft-float -Uunicore32
+KBUILD_AFLAGS	+=-msoft-float
+

Is it realistic to even support gcc 2.x versions on a recent kernel?

quoted

+drivers-$(CONFIG_ARCH_PUV3)	+= drivers/staging/puv3/
+
+libs-y				+= arch/unicore32/lib/
+libs-y				+= $(shell $(CC) $(KBUILD_CFLAGS) -print-file-name=libc.a)
+libs-y				+= $(shell $(CC) $(KBUILD_CFLAGS) -print-file-name=libgcc.a)
+

The libgcc thing is not too surprising, but you do have
-print-libgcc-file-name for this. That libc.a thing however needs some
explaining.

All  above is corrected,  please see following  arch/unicore32/Makefile:

diff --git a/arch/unicore32/Makefile b/arch/unicore32/Makefile
new file mode 100644
index 0000000..8718152
--- /dev/null
+++ b/arch/unicore32/Makefile

@@ -0,0 +1,144 @@
+#
+# arch/unicore32/Makefile
+#
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
+# This file is subject to the terms and conditions of the GNU General Public
+# License.  See the file "COPYING" in the main directory of this archive
+# for more details.
+#
+# Copyright (C) 2002~2010 by Guan Xue-tao
+ifneq ($(SUBARCH),$(ARCH))
+	ifeq ($(CROSS_COMPILE),)
+		CROSS_COMPILE := $(call cc-cross-prefix, unicore32-linux-)
+	endif
+endif
+
+LDFLAGS_vmlinux	:=-p --no-undefined -X
+
+OBJCOPYFLAGS	:=-O binary -R .note -R .note.gnu.build-id -R .comment -S
+GZFLAGS		:=-9
+
+# Explicitly specifiy 32-bit UniCore ISA:
+KBUILD_CFLAGS	+=$(call cc-option,-municore32)
+
+# Never generate .eh_frame
+KBUILD_CFLAGS	+=$(call cc-option,-fno-dwarf2-cfi-asm)
+
+KBUILD_CFLAGS	+=-msoft-float
+
+ifeq ($(CONFIG_FRAME_POINTER),y)
+KBUILD_CFLAGS	+=-mno-sched-prolog
+endif
+
+CHECKFLAGS	+= -D__unicore32__
+
+#Default value
+head-y		:= arch/unicore32/kernel/head.o arch/unicore32/kernel/init_task.o
+textofs-y	:= 0x00408000
+
+# The byte offset of the kernel image in RAM from the start of RAM.
+TEXT_OFFSET := $(textofs-y)
+
+export	TEXT_OFFSET GZFLAGS
+
+core-y				+= arch/unicore32/kernel/ arch/unicore32/mm/
+core-$(CONFIG_UNICORE_FPU_F64)	+= arch/unicore32/uc-f64/
+
+drivers-$(CONFIG_ARCH_PUV3)	+= drivers/staging/puv3/
+
+libs-y				+= arch/unicore32/lib/
+# include libc.a in libs-y for string functions, like memcpy and so on.
+libs-y				+= $(shell $(CC) $(KBUILD_CFLAGS) -print-file-name=libc.a)
+libs-y				+= $(shell $(CC) $(KBUILD_CFLAGS) -print-file-name=libgcc.a)
+
+# Default target when executing plain make
+KBUILD_IMAGE := zImage
+
+all:	$(KBUILD_IMAGE)
+
+boot := arch/unicore32/boot
+
+ASM_GENERIC_HEADERS	:= arch/unicore32/include/asm/atomic.h			\
+			   arch/unicore32/include/asm/auxvec.h			\
+			   arch/unicore32/include/asm/bitsperlong.h		\
+			   arch/unicore32/include/asm/bug.h			\
+			   arch/unicore32/include/asm/bugs.h			\
+			   arch/unicore32/include/asm/cputime.h			\
+			   arch/unicore32/include/asm/current.h			\
+			   arch/unicore32/include/asm/device.h			\
+			   arch/unicore32/include/asm/div64.h			\
+			   arch/unicore32/include/asm/emergency-restart.h	\
+			   arch/unicore32/include/asm/errno.h			\
+			   arch/unicore32/include/asm/fb.h			\
+			   arch/unicore32/include/asm/fcntl.h			\
+			   arch/unicore32/include/asm/hardirq.h			\
+			   arch/unicore32/include/asm/hw_irq.h			\
+			   arch/unicore32/include/asm/ioctl.h			\
+			   arch/unicore32/include/asm/ioctls.h			\
+			   arch/unicore32/include/asm/ipcbuf.h			\
+			   arch/unicore32/include/asm/irq_regs.h		\
+			   arch/unicore32/include/asm/kdebug.h			\
+			   arch/unicore32/include/asm/kmap_types.h		\
+			   arch/unicore32/include/asm/local.h			\
+			   arch/unicore32/include/asm/mman.h			\
+			   arch/unicore32/include/asm/module.h			\
+			   arch/unicore32/include/asm/msgbuf.h			\
+			   arch/unicore32/include/asm/param.h			\
+			   arch/unicore32/include/asm/parport.h			\
+			   arch/unicore32/include/asm/percpu.h			\
+			   arch/unicore32/include/asm/poll.h			\
+			   arch/unicore32/include/asm/posix_types.h		\
+			   arch/unicore32/include/asm/resource.h		\
+			   arch/unicore32/include/asm/scatterlist.h		\
+			   arch/unicore32/include/asm/sections.h		\
+			   arch/unicore32/include/asm/sembuf.h			\
+			   arch/unicore32/include/asm/serial.h			\
+			   arch/unicore32/include/asm/shmbuf.h			\
+			   arch/unicore32/include/asm/shmparam.h		\
+			   arch/unicore32/include/asm/siginfo.h			\
+			   arch/unicore32/include/asm/signal.h			\
+			   arch/unicore32/include/asm/socket.h			\
+			   arch/unicore32/include/asm/sockios.h			\
+			   arch/unicore32/include/asm/statfs.h			\
+			   arch/unicore32/include/asm/termbits.h		\
+			   arch/unicore32/include/asm/termios.h			\
+			   arch/unicore32/include/asm/topology.h		\
+			   arch/unicore32/include/asm/types.h			\
+			   arch/unicore32/include/asm/ucontext.h		\
+			   arch/unicore32/include/asm/unaligned.h		\
+			   arch/unicore32/include/asm/user.h			\
+			   arch/unicore32/include/asm/vga.h			\
+			   arch/unicore32/include/asm/xor.h
+
+%.h:
+	$(Q)echo '#include <asm-generic/$(notdir $@)>' > $@
+
+archprepare: $(ASM_GENERIC_HEADERS)
+
+# Convert bzImage to zImage
+bzImage: zImage
+
+zImage Image uImage: vmlinux
+	$(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $(boot)/$@
+
+zinstall install: vmlinux
+	$(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $@
+
+CLEAN_FILES += $(ASM_GENERIC_HEADERS)
+
+# We use MRPROPER_FILES and CLEAN_FILES now
+archclean:
+	$(Q)$(MAKE) $(clean)=$(boot)
+
+define archhelp
+  echo  '* zImage        - Compressed kernel image (arch/$(ARCH)/boot/zImage)'
+  echo  '  Image         - Uncompressed kernel image (arch/$(ARCH)/boot/Image)'
+  echo  '  uImage        - U-Boot wrapped zImage'
+  echo  '  install       - Install uncompressed kernel'
+  echo  '  zinstall      - Install compressed kernel'
+  echo  '                  Install using (your) ~/bin/$(INSTALLKERNEL) or'
+  echo  '                  (distribution) /sbin/$(INSTALLKERNEL) or'
+  echo  '                  install to $$(INSTALL_PATH) and run lilo'
+endef

quoted

diff --git a/arch/unicore32/kernel/asm-offsets.c b/arch/unicore32/kernel/asm-offsets.c
new file mode 100644
index 0000000..ffcbe75
--- /dev/null
+++ b/arch/unicore32/kernel/asm-offsets.c
+/*
+ * GCC 3.0, 3.1: general bad code generation.
+ * GCC 3.2.0: incorrect function argument offset calculation.
+ * GCC 3.2.x: miscompiles NEW_AUX_ENT in fs/binfmt_elf.c
+ *	(http://gcc.gnu.org/PR8896) and incorrect structure
+ *		initialisation in fs/jffs2/erase.c
+ */
+#if (__GNUC__ < 4)
+#error Your compiler should upgrade to uc4
+#error	Known good compilers: 4.2.2
+#endif
+

If your compiler situation is this screwed up, then you need to be
erroring out in the Makefile, and you can most certainly kill off that
gcc 2.x cruft.

OK.

quoted

+++ b/arch/unicore32/kernel/vmlinux.lds.S

@@ -0,0 +1,120 @@
+/*
+ * linux/arch/unicore32/kernel/vmlinux.lds.S
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <asm-generic/vmlinux.lds.h>
+#include <asm/thread_info.h>
+#include <asm/memory.h>
+#include <asm/page.h>
+
+OUTPUT_ARCH(unicore32)
+ENTRY(stext)
+
+jiffies = jiffies_64;
+
+SECTIONS
+{
+	. = PAGE_OFFSET + TEXT_OFFSET;
+
+	.init : {			/* Init code and data		*/
+		_stext = .;
+		_sinittext = .;
+			HEAD_TEXT
+			INIT_TEXT
+		_einittext = .;
+
+		INIT_SETUP(16)
+
+		INIT_CALLS
+		CON_INITCALL
+		SECURITY_INITCALL
+		INIT_RAM_FS
+
+		__init_begin = _stext;
+		INIT_DATA
+	}
+

This looks really broken, please take a look at asm-generic/vmlinux.lds.h
and use that as a model. Any reasons you have for needing to deviate from
that should be thoroughly explained.

Ok, I will rewrite this file lator.

Thanks paul.

Guan Xuetao