PW2 diags image needed

[rnbw]

Hello,
I have a PW2 4GB with bootloop problem which ends with "Repair Needed" screen. I've attached serial, exported FAT, copied the latest update file from Amazon and it flashed fine. But the bootloop is still present. I can see the new uboot and kernel on serial console. Maybe the /var/local partition is corrupted?

The bad thing is that diags does not work. It starts to boot but ends with

kinit: init not found!

Looks like I need to reflash diags using fastboot but I'm unable to find any images online.

Could anyone help, please?

[eddie.t.h]

Maybe you could try this: repeat your previous steps but instead of an update file, upload an empty file named DO_FACTORY_RESTORE.

[rnbw]

Thanks, it did something - a language selector came on the screen! However, the touchscreen X axis is mirrored (tapped English on the left side but Russian on the right side was highlighted). After selecting language, the bootloop is back.

I was told that the screen was replaced before it stopped working. I've disconnected the wide flex cable and there's a label saying ED060KD1. That's a PW3 screen. That's why the tree logo is not full-screen. The language selector was, however, full-screen. Could the wrong screen cause the lab126_gui not to start?

[katadelos]

Originally Posted by rnbw

Thanks, it did something - a language selector came on the screen! However, the touchscreen X axis is mirrored (tapped English on the left side but Russian on the right side was highlighted). After selecting language, the bootloop is back.

I was told that the screen was replaced before it stopped working. I've disconnected the wide flex cable and there's a label saying ED060KD1. That's a PW3 screen. That's why the tree logo is not full-screen. The language selector was, however, full-screen. Could the wrong screen cause the lab126_gui not to start?

You can grab a diags image for PW2 here.

You might be SOL though - I've got a pair of Kindles with PW3 motherboards but PW2 screens so, the opposite problem that you have.

I was able to get them to stop bootlooping by installing a PW2 firmware image on them (which solved the scaling issue) and was able to patch out the X axis mirroring from the touch screen driver but touch broke completely on both devices shortly afterwards, even in diags mode with the stock touch driver.

IIRC it was something to do with the I2C bus?

[eddie.t.h]

You must have something pretty messed up in your system. What is your reader serial number? Maybe you have a PW3 after all?

[rnbw]

Thanks for the link with images, I was unable to find them.

It's definitely PW2 - serial number begins with 9017, PCB is marked 30-000539.
Probably the best option is to get a PW2 screen and sell the PW3 one.

[j.p.s]

Originally Posted by rnbw

I was told that the screen was replaced before it stopped working. I've disconnected the wide flex cable and there's a label saying ED060KD1. That's a PW3 screen.

Originally Posted by katadelos

I've got a pair of Kindles with PW3 motherboards but PW2 screens so, the opposite problem that you have.

Originally Posted by rnbw

It's definitely PW2 - serial number begins with 9017, PCB is marked 30-000539.
Probably the best option is to get a PW2 screen and sell the PW3 one.

Maybe you two should trade screens.

[eddie.t.h]

Originally Posted by rnbw

Probably the best option is to get a PW2 screen and sell the PW3 one.

I think a better option though is to look for a PW3 with a broken display.

[rnbw]

Or try to flash the PW2 board to PW3?

I wonder why the touch was still mirrored with PW2 firmware for katadelos. Maybe there's a difference in the touchscreen connector pinout?

[eddie.t.h]

These motherboard, despite their great similarities, are different. From the most important differences PW3 has 512MB ram, voltage switch for Flash memory. Possibly there are also differences on i2c bus. Uboot recognizes the board configuration by serial numbers. I don't know if you will be able to simply swap systems.

[rnbw]

Oh, haven't noticed the difference in RAM size. Smaller RAM is probably a showstopper.

[katadelos]

Originally Posted by rnbw

Or try to flash the PW2 board to PW3?

I wonder why the touch was still mirrored with PW2 firmware for katadelos. Maybe there's a difference in the touchscreen connector pinout?

It's the same pinout (though possibly different voltages?) and driver; the screen stayed mirrored because the driver checks the PCB serial number when it loads and uses this value to define whether mirroring should be applied:

# From drivers/input/touchscreen/cyttsp4_mt_common.c

#define PANEL_FLIP_X   (lab126_board_is(BOARD_ID_MUSCAT_WAN) || \
                        lab126_board_is(BOARD_ID_MUSCAT_WFO) || \
                         lab126_board_is(BOARD_ID_MUSCAT_32G_WFO))
	
#define PANEL_FLIP_Y   (lab126_board_is(BOARD_ID_WHISKY_WAN) || \
                         lab126_board_is(BOARD_ID_WHISKY_WFO) || lab126_board_is(BOARD_ID_WOODY))

Originally Posted by eddie.t.h

These motherboard, despite their great similarities, are different. From the most important differences PW3 has 512MB ram, voltage switch for Flash memory. Possibly there are also differences on i2c bus. Uboot recognizes the board configuration by serial numbers. I don't know if you will be able to simply swap systems.

There's a good change that booting the firmware of a different device is possible - PW2, PW3, KT2 and KV are very similar on the software side of things and use an identical configuration for Linux + U-Boot builds. There's still a good chance that the hardware will get screwed up though.

Originally Posted by rnbw

Oh, haven't noticed the difference in RAM size. Smaller RAM is probably a showstopper.

Nah, shouldn't be - the only time that memory exhaustion is an issue is when attempting to run the new UI on a 256MB device. You can run 5.14.1 on a KT2 or PW2 without problems as long as the old UI is enabled.

[eddie.t.h]

Originally Posted by katadelos

There's a good change that booting the firmware of a different device is possible - PW2, PW3, KT2 and KV are very similar on the software side of things and use an identical configuration for Linux + U-Boot builds. There's still a good chance that the hardware will get screwed up though.

I wonder if by changing serial numbers of reader and pcb to those of PW3 you could easily install the system in the traditional way without recompiling drivers? Have you tried that with your readers?

[rnbw]

I got the correct screen (ED060XD4) and the Kindle now works fine - no more bootloop.

I've also reflashed diags using fastboot and the image katadelos provided - thanks a lot.