[U-Boot] [PATCH v2] add nand spl boot for qi_lb60 board

[Scott Wood <scottwood@freescale.com>]

On 01/06/2012 04:17 AM, Xiangfu Liu wrote:
> Signed-off-by: Xiangfu Liu <xiangfu@openmobilefree.net>
> ---
>  arch/mips/cpu/xburst/cpu.c           |    4 +
>  arch/mips/cpu/xburst/start_spl.S     |   65 ++++++++++++++++++++
>  drivers/mtd/nand/jz4740_nand.c       |   40 +++++++++++-
>  include/configs/qi_lb60.h            |    3 +
>  nand_spl/board/qi/qi_lb60/Makefile   |  112 ++++++++++++++++++++++++++++++++++
>  nand_spl/board/qi/qi_lb60/nand_spl.c |   37 +++++++++++
>  nand_spl/board/qi/qi_lb60/u-boot.lds |   63 +++++++++++++++++++
>  7 files changed, 321 insertions(+), 3 deletions(-)
>  create mode 100644 arch/mips/cpu/xburst/start_spl.S
>  create mode 100644 nand_spl/board/qi/qi_lb60/Makefile
>  create mode 100644 nand_spl/board/qi/qi_lb60/nand_spl.c
>  create mode 100644 nand_spl/board/qi/qi_lb60/u-boot.lds

We are transitioning from nand_spl/ to spl/.  Please try to work within
the new infrastructure.  You may run into problems with size in spl/,
due to gc-sections not removing strings on components you don't need --
I plan to fix those issues (for NAND), hopefully this merge window, by
requiring all files to be explicitly asked for.  Feel free to fix them
first if you'd like. :-)

> diff --git a/arch/mips/cpu/xburst/cpu.c b/arch/mips/cpu/xburst/cpu.c
> index e976341..afd166c 100644
> --- a/arch/mips/cpu/xburst/cpu.c
> +++ b/arch/mips/cpu/xburst/cpu.c
> @@ -42,6 +42,8 @@
>  		:			\
>  		: "i" (op), "R" (*(unsigned char *)(addr)))
>  
> +#ifndef CONFIG_NAND_SPL
> +
>  void __attribute__((weak)) _machine_restart(void)
>  {
>  	struct jz4740_wdt *wdt = (struct jz4740_wdt *)JZ4740_WDT_BASE;
> @@ -109,6 +111,8 @@ void invalidate_dcache_range(ulong start_addr, ulong stop)
>  		cache_op(Hit_Invalidate_D, addr);
>  }
>  
> +#endif
> +
>  void flush_icache_all(void)
>  {
>  	u32 addr, t = 0;
> diff --git a/arch/mips/cpu/xburst/start_spl.S b/arch/mips/cpu/xburst/start_spl.S
> new file mode 100644
> index 0000000..f137ccd
> --- /dev/null
> +++ b/arch/mips/cpu/xburst/start_spl.S
> @@ -0,0 +1,65 @@
> +/*
> + *  Startup Code for MIPS32 XBURST CPU-core
> + *
> + *  Copyright (c) 2010 Xiangfu Liu <xiangfu@sharism.cc>
> + *
> + * See file CREDITS for list of people who contributed to this
> + * project.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 3 of
> + * the License, or (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
> + * MA 02111-1307 USA
> + */
> +
> +#include <config.h>
> +#include <version.h>
> +#include <asm/regdef.h>
> +#include <asm/mipsregs.h>
> +#include <asm/addrspace.h>
> +#include <asm/cacheops.h>
> +
> +#include <asm/jz4740.h>
> +
> +	.set noreorder
> +
> +	.globl _start
> +	.text
> +_start:
> +	.word JZ4740_NANDBOOT_CFG /* fetched during NAND Boot */
> +reset:
> +	/*
> +	 * STATUS register
> +	 * CU0=UM=EXL=IE=0, BEV=ERL=1, IP2~7=1
> +	 */
> +	li	t0, 0x0040FC04
> +	mtc0	t0, CP0_STATUS
> +	/*
> +	 * CAUSE register
> +	 * IV=1, use the specical interrupt vector (0x200)
> +	 */
> +	li	t1, 0x00800000
> +	mtc0	t1, CP0_CAUSE
> +
> +	bal     1f
> +	 nop
> +	.word   _GLOBAL_OFFSET_TABLE_
> +1:
> +	move    gp, ra
> +	lw      t1, 0(ra)
> +	move	gp, t1
> +
> +	la	sp, 0x80004000
> +	la	t9, nand_spl_boot
> +	j	t9
> +	 nop

Shinya, do the MIPS parts look OK?

> +include $(TOPDIR)/config.mk
> +
> +LDSCRIPT= $(TOPDIR)/nand_spl/board/$(BOARDDIR)/u-boot.lds
> +LDFLAGS	= -Bstatic -T $(LDSCRIPT) -Ttext $(CONFIG_NAND_SPL_TEXT_BASE)
> +AFLAGS	+= -DCONFIG_NAND_SPL
> +CFLAGS	+= -DCONFIG_NAND_SPL -O2

Why -O2 and not the -Os that you should already be inheriting from
config.mk?

> +# The JZ4740 CPU can load two areas of data from NAND flash to internal SRAM,
> +# one is the normal area up to 8KB starting from NAND flash address 0, the
> +# other is the backup area up to 8KB starting from NAND flash address 0x2000.
> +
> +# After reset, the boot program will first read the normal area data from NAND
> +# flash using hardware Reed-Solomon ECC. If no ECC error is detected or ECC
> +# error is correctable, the boot program then branches to internal SRAM at 4
> +# bytes offset. ff it detects an uncorrectable ECC error, it will continue to
> +# read the backup area of data from NAND flash using hardware Reed-Solomon ECC.

Why must the payload come at offset 256K, rather than 16K?

> +
> +# those 'dd' commands is for create such two 8KB for JZ4740 CPU
> +$(nandobj)u-boot-spl-16k.bin: $(nandobj)u-boot-spl.bin
> +	dd bs=1024 count=8 if=/dev/zero of=$(nandobj)junk1
> +	cat $< $(nandobj)junk1 > $(nandobj)junk2
> +	dd bs=1024 count=8 if=$(nandobj)junk2 of=$(nandobj)junk3
> +	cat $(nandobj)junk3 $(nandobj)junk3 > $(nandobj)junk4
> +	dd bs=1024 count=256 if=/dev/zero of=$(nandobj)junk5
> +	cat $(nandobj)junk4 $(nandobj)junk5 > $(nandobj)junk6
> +	dd bs=1024 count=256 if=$(nandobj)junk6 of=$@
> +	rm -f $(nandobj)junk*

This is overcomplicated and difficult to follow.

Try something like this:

# This target is misnamed, but that's the toplevel Makefile's fault
$(nandobj)u-boot-spl-16k.bin: $(nandobj)u-boot-spl.bin
	dd if=$< of=$@ conv=sync bs=8192 count=1
	dd if=$< of=$@ conv=sync,notrunc oflag=append \
		bs=8192 count=1
	dd if=/dev/zero of=$@ conv=sync,notrunc oflag=append \
		bs=245760 count=1

Or consider using --pad-to or the linker script to add the 8K padding
(also add an assert for too-large like
arch/powerpc/cpu/mpc85xx/u-boot-nand_spl.lds does).  If you also get rid
of the need to pad to 256k, this step then becomes "cat $< $< > $@".

> diff --git a/nand_spl/board/qi/qi_lb60/u-boot.lds b/nand_spl/board/qi/qi_lb60/u-boot.lds
> new file mode 100644
> index 0000000..7042388
> --- /dev/null
> +++ b/nand_spl/board/qi/qi_lb60/u-boot.lds
> @@ -0,0 +1,63 @@
> +/*
> + * (C) Copyright 2005
> + * Ingenic Semiconductor, <jlwei@ingenic.cn>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
> + * MA 02111-1307 USA
> + */
> +
> +OUTPUT_FORMAT("elf32-tradlittlemips", "elf32-tradlittlemips", "elf32-tradlittlemips")
> +
> +OUTPUT_ARCH(mips)
> +ENTRY(_start)
> +SECTIONS
> +{
> +	. = 0x00000000;

include/configs/qi_lb60.h says CONFIG_NAND_SPL_TEXT_BASE is 0x80000000,
not zero.

-Scott