[Arm-netbook] 2.7.4 preproduction sample, 1.7 MD, Questions

[Luke Kenneth Casson Leighton]

(btw thank you paul - and pablo - both)

On Sun, Jul 19, 2020 at 12:18 PM Pablo Rath <pablo at parobalth.org> wrote:
>
> >On Sat, Jul 18, 2020 at 07:19:37PM +0200, Paul Boddie wrote:
> >
> > I saw that there is a section about legacy U-Boot in the page:
> >
> > http://rhombus-tech.net/allwinner/a20/EOMA68-A20_2-7-4_preproduction/
> >
>
> Yes, obviously I had to start with U-Boot first.
> Luke told me that sunxi U-Boot should build fine and that nothing has
> changed so I started there.
>
> For mainline U-Boot I still need a valid config file to do 'make
> eoma68_foo_defconfig'. There is a .dts file here
> (http://rhombus-tech.net/allwinner/a20/boot/sun7i-a20-eoma68-a20.dts)
> but I don't know if it was used for mainline U-Boot and not just for
> Kernel compilation.

it would be both (for mainline in each case).

> I have realised that on Debian gcc versions are kept installed.

yes, i have 35 separate different gcc compiler packages installed and
unfortunately at some point i removed the gnueabihf arm 4.7.2 one.
damn

> I have
> a native armhf installation (initially installed with Jessie) currently
> upgraded to stretch and gcc-4.9 is still installed. Changed between gcc
> versions with 'update-alternatives'. I don't know if this also apllies
> to cross-toolchains because my experience with crossbuilding is limited.

export the right environment variables and it's not necessary to use
"update-alternatives".

export CC=gcc-4.9
export CROSS_COMPILE=arm-linux-gnueabihf- (or something)
export ARCH=arm

or just:

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- CC=gcc-4.9 {insertwhatever}

yes, here you go, the "make blah blah" lines:
http://rhombus-tech.net/allwinner/a20/boot/

just add the extra parameter CC=gcc-4.9 (or gcc-4.7)


> Sid (unstable) still has gcc-4.9 and even gcc-4.7 native armhf packages
> so this could be another solution I have not tested yes as I have no
> armhf sid installation.

arse.  this is the earliest i can find so far.

http://ftp.debian.org/debian/pool/main/g/gcc-6-cross/

that *might* be back far enough to work.


> This is extremly helpful. I am going to try it out. Can you copy that to
> the wiki?

yes please, paul.

> > This should get you the u-boot-sunxi-with-spl.bin file that needs to be
> > deployed.
>
> Good news is that I made it to the sunxi U-Boot prompt on Friday. Booted
> via USB-FEL. So my
> soldered Pins, UART connection, Power Supply, µUSB-OTG on the card work fine.

fantastic!

> Next I have planned to compile a sunxi 3.4 Kernel and debootstrap a
> Debian rootfs.

you should pretty much be able to download and use anything.  use
debootstrap if you like (in cross-arch mode).  this you can do using
qemu-arm to "prepare / finish" things.  actually there's now a
qemu-debootstrap command so it should be dead simple:

http://logan.tw/posts/2017/01/21/introduction-to-qemu-debootstrap/


> Then I want to try mainline U-Boot and a mainline Kernel.

good idea.

l.