[Tinkerphones] RAM/NAND signals from GTA04A5

[H. Nikolaus Schaller]

Hi,
I am still working a little to polish our Letux software
for the GTA04A5 device.

The biggest change to the GTA04A3/A4 is the RAM/NAND chip.
It has 1 GB RAM and 512 MB NAND. Well, OneNAND - which is
quite different :)

I have played around with U-Boot 2016.11 config and now have
a version where something seems to work. At least in U-Boot
(I still need to use the standard-NAND MLO because the OneNAND
SPL does simply hang).

Here is some annotated boot log (so that you can make yourself
used a little about what you can expect from the GTA04A5 devices):

> tذb$U   @D  @
> U-Boot SPL 2016.11-00171-g46574ac-dirty (Jan 02 2017 - 18:38:58)

^^^ freshly compiled...

> Trying to boot from MMC1
> pop_mfr = ff pop_id = ff

^^^ this is a message which tells that U-Boot tries to identify
the NAND in NAND mode, but we have some OneNAND. So it fails.

> Found GTA04A5

^^^ version detection resistors are recognised :)

> reading u-boot.img
> reading u-boot.img
> 
> 
> U-Boot 2016.11-00171-g46574ac-dirty (Jan 02 2017 - 20:00:08 +0100)

^^^ still hot in the pan :)

> 
> OMAP36XX/37XX-GP ES1.2, CPU-OPP2, L3-200MHz, Max CPU Clock 1 Ghz

^^^ we have the 1GHz CPU

> GTA04 + LPDDR/OneNAND

^^^ U-Boot knows that it has OneNAND

> I2C:   ready
> DRAM:  1 GiB

^^^ plenty of RAM :)

> NAND:  Muxed OneNAND 512MB 1.8V 16-bit (0x50)
> OneNAND version = 0x0232
> Chip support all block unlock
> Chip has 4KiB pagesize
> Scanning device for bad blocks

^^^ seems to be ok!

> onenand_bbt_wait: controller error = 0x0400

^^^ no idea what this means

> Bad eraseblock 843 at 0x0d2c0000

^^^ ok, one bad block is not so bad :)

> OneNAND: 512 MiB

^^^ wow - full size found :)

> MMC:   OMAP SD/MMC: 0
> *** Warning - bad CRC, using default environment

^^^ OneNAND has never been written - so this is to be expected

> 
> OMAP die ID: 51ac00029ff80000015a98820701a02d
> Found GTA04A5
> Device Tree: omap3-gta04a5.dtb

^^^ device knows which device tree to load

> gpio175 = 1

^^^ this is from some internal test (it checks if the IrDA receiver is turned off)

> Net:   usb_ether
> Error: usb_ether address not set.
> 
> Hit any key to stop autoboot:  0 
> switch to partitions #0, OK
> mmc0 is current device
> gpio: pin 173 (gpio 173) value is 1
> gpio: pin 7 (gpio 7) value is 0
> SD/MMC found on device 0
> reading uEnv.txt
> ** Unable to read file uEnv.txt **

^^^ I have deleted it from this SD card so that it always falls into U-Boot console

> reading boot.scr
> ** Unable to read file boot.scr **
> ** File not found /boot/uImage **
> Booting from nand ...

^^^ ok, it tries NAND

> 
> OneNAND read: offset 0x280000, size 0x400000
>  4194304 bytes read: OK

^^^ wow - kernel partition loaded to RAM (but it should be 6MB because kernels are >4MB for a while)

> Wrong Image Format for bootm command

^^^ well, the partition is empty because no kernel is installed

> ERROR: can't get kernel image!
> ** File not found /boot/zImage **
> GTA04 # 

I will keep you updated on further progress.

BR,
Nikolaus