[LEDE-DEV] Compiling ar71xx/generic/wrt400n does not lead to installable firmware

[Yousong Zhou]

Hi, Frank

On 1 August 2016 at 02:34, Frank Horowitz <frank at horow.net> wrote:
> Hi Yousong (et al.),
>
> (The original Subject mentioning “packages” instead of “firmware” was my mistake. The packages actually appear to be building just fine.)
>
> Yes, the lede-ar71xx-generic-uImage-lzma.bin file comes in at size 1368491 which is over the 1310720 size listed in the makefiles.
>
> Here is the relevant partition size table from dmesg on the hardware running CC 15.05.1:
>
> [    1.060000] Creating 9 MTD partitions on "spi0.0":
> [    1.070000] 0x000000000000-0x000000030000 : "uboot"
> [    1.070000] 0x000000030000-0x000000040000 : "env"
> [    1.080000] 0x000000040000-0x000000180000 : "linux"
> [    1.080000] 0x000000180000-0x0000007b0000 : "rootfs"
> [    1.090000] mtd: device 3 (rootfs) set to be root filesystem
> [    1.100000] 1 squashfs-split partitions found on MTD device rootfs
> [    1.100000] 0x0000003a0000-0x0000007b0000 : "rootfs_data"
> [    1.110000] 0x0000007b0000-0x0000007c0000 : "nvram"
> [    1.120000] 0x0000007c0000-0x0000007d0000 : "factory"
> [    1.120000] 0x0000007d0000-0x0000007f0000 : "language"
> [    1.130000] 0x0000007f0000-0x000000800000 : "caldata"
> [    1.130000] 0x000000040000-0x0000007b0000 : “firmware"
>

I am not sure, but does sysupgrade ever work for this device?  I ask
because it looks like the "firmware" part includes a non-relevant
"linux" part.  Also I am curious what the "linux" part for.  It would
be helpful if these info are available in the device wiki page.

> And here is my attempt at a patch mimicking your mods for the HiWiFi HC6361:
>
> ---BEGIN PATCH---
>
> diff --git a/target/linux/ar71xx/image/generic.mk b/target/linux/ar71xx/image/generic.mk
> index cb57dba..489aef3 100644
> --- a/target/linux/ar71xx/image/generic.mk
> +++ b/target/linux/ar71xx/image/generic.mk
> @@ -461,6 +461,26 @@ define Device/hiwifi-hc6361
>  endef
>  TARGET_DEVICES += hiwifi-hc6361
>
> +define Build/uImageWRT400N
> +       mkimage -A $(LINUX_KARCH) \
> +               -O linux -T kernel \
> +               -C $(1) -a $(KERNEL_LOADADDR) -e $(if $(KERNEL_ENTRY),$(KERNEL_ENTRY),$(KERNEL_LOADADDR)) \
> +               -n '$(call toupper,$(LINUX_KARCH)) LEDE Linux-$(LINUX_VERSION)' -d $@ $@.new
> +       @mv $@.new $@
> +endef
> +
> +define Device/linksys-wrt400n
> +  DEVICE_TITLE := Linksys WRT400N
> +  DEVICE_PACKAGES :=
> +  BOARDNAME := Linksys-WRT400N
> +  DEVICE_PROFILE := LINKSYS_WRT400N
> +  IMAGE_SIZE := 7616k
> +  KERNEL := kernel-bin | patch-cmdline | lzma | uImageWRT400N lzma
> +  CONSOLE := ttyS0,115200
> +  MTDPARTS := spi0.0:192k(u-boot)ro,64k(u-boot-env)ro,7616k(firmware),64k(nvram)ro,64k(factory)ro,128k(language)ro,64k(calda
> ta)ro,64k(factory)ro
> +endef
> +TARGET_DEVICES += linksys-wrt400n
> +
>
>  # The pre-filled 64 bytes consist of
>  # - 28 bytes seama_header
> diff --git a/target/linux/ar71xx/image/legacy.mk b/target/linux/ar71xx/image/legacy.mk
> index c2daba9..30501cd 100644
> --- a/target/linux/ar71xx/image/legacy.mk
> +++ b/target/linux/ar71xx/image/legacy.mk
> @@ -322,15 +322,6 @@ define Image/BuildKernel/Initramfs
>         $(call Image/Build/Initramfs)
>  endef
>
> -Image/Build/WRT400N/buildkernel=$(call MkuImageLzma,$(2),$(3))
> -
> -define Image/Build/WRT400N
> -       $(call Sysupgrade/KRuImage,$(1),$(2),1310720,6488064)
> -       if [ -e "$(call sysupname,$(1),$(2))" ]; then \
> -               wrt400n $(KDIR_TMP)/vmlinux-$(2).uImage $(KDIR)/root.$(1) $(call factoryname,$(1),$(2)); \
> -       fi
> -endef
> -
>
>  define Image/Build/CameoAP94/buildkernel
>         $(call MkuImageLzma,$(2),$(3) $(4))
> @@ -1054,8 +1045,6 @@ $(eval $(call SingleProfile,WHRHPG300N,64kraw,WHRHPG300N,whr-hp-g300n,WHR-HP-G30
>  $(eval $(call SingleProfile,WHRHPG300N,64kraw,WHRHPGN,whr-hp-gn,WHR-HP-GN,ttyS0,115200,$$(whrhpg300n_mtdlayout),WHR-HP-GN))
>  $(eval $(call SingleProfile,WHRHPG300N,64kraw,WLAEAG300N,wlae-ag300n,WLAE-AG300N,ttyS0,115200,$$(whrhpg300n_mtdlayout),WLAE-AG300N))
>
> -$(eval $(call SingleProfile,WRT400N,64k,WRT400N,wrt400n,WRT400N,ttyS0,115200))
> -
>  $(eval $(call SingleProfile,WZRHP128K,128kraw,WZRHPG300NH,wzr-hp-g300nh,WZR-HP-G300NH,ttyS0,115200,WZR-HP-G300NH))
>  $(eval $(call SingleProfile,WZRHP64K,64kraw,WZRHPG300NH2,wzr-hp-g300nh2,WZR-HP-G300NH2,ttyS0,115200,WZR-HP-G300NH2))
>  $(eval $(call SingleProfile,WZRHP64K,64kraw,WZRHPAG300H,wzr-hp-ag300h,WZR-HP-AG300H,ttyS0,115200,WZR-HP-AG300H))
>
> —END PATCH---
>
> Now clearly there is still something wrong somewhere, since this did not produce either a *-sysupgrade.bin or *-factory.bin firmware binary.
>
> Could someone who actually knows what they are doing (not me! :-) please have a look at my above patch? In particular, I couldn’t figure out how to specify that
> the kernel needs 0x150000 (actually 0x14E000) of space rather than 0x140000 from the CC version in the dmesg table above. Do I need to specify all of the internal boundaries in the squashfs-split partitions? If so, how?
>
> I’m somewhat leery to flash any binary result to the router, since I don’t have a serial line soldered in to that particular piece of hardware. My brick potential is fairly high here IMHO.
>
> TIA for your help!
>
> Cheers,
>         Frank Horowitz

With mtdsplit, it's the size of "firmware" part that matters.
"firmware" will contain kernel, rootfs, and the space left will be for
rootfs_data.

As for the sysupgrade image did not get generated with the patch, was
it possible that the .config was not updated?

Anyway, I think the patch in its current form won't work (the
BOARDNAME does not match with the one in mach-wrt400n.c) and having
serial access to the device will be handy.

Cheers,
                yousong