Hi Keith,
On Sun, Jan 26, 2020 at 9:41 PM Keith Hui buurin@gmail.com wrote:
Hi list,
Seeing that my beloved i440BX platform will not support enough memory to run Windows 10, and with 7 EOLed, its days are numbered even though I enjoyed working on a blob-free platform.
I am now setting myself up for porting coreboot to my P8Z77-M board, where a close cousin is already in the tree.
I would use autoport, and then add it as a variant of the P8Z77-M PRO. I have yet another cousin of these mainboards, the P8Z77-M LX2.
First, I need a 8MB SPI flash chip. I picked up a two W25Q64JVSSIM from Digikey and some adapter as well since they don't carry any in DIP form anymore. :( I mounted one and it seems to physically work. It wasn't supported in flashrom yet, so I sent a patch there as well [1], flagged as untested, because an issue I'll get to later, and my reason for this email.
Next, I need a SPI flash programmer. I'm trying to avoid making major purchases. The most handy thing I have is a 5V Arduino Mega 2560 r3, so I loaded frser-duino on it, and HoodLoader2 on its 16u2 for the fast USB. I also picked up a level shifter module [2] because the chips are 3.3V. When I wired up everything on a breadboard with the board's original chip it reads fine and I was actually able to save a backup of its contents. Of course I then wanted to build something that I can just plug the chip in and go, as I will need to use it quite often.
I wired the level shifter and a DIP socket on a XBee shield (because it has a 3.3V regulator and a proto area), but it's not detecting the chip. I then reverted to the breadboard, this time using 3 resistor dividers for level shifting because the level shifter's legs are now soldered on the shield.
I read the (still virgin) chip 3 times, and saw the read bytes periodically goes to 0x00 instead of being all 0xff, as expected from an unprogrammed chip. The connection is not working right.
What else can I try? If I can't get this serprog-on-an-arduino setup working, what is my next best setup I can use?
I've always had issues when using an Arduino. I would only use it if nothing else is available. I have a pair of FT2232H, and they work pretty well as flashrom SPI programmers. They are much faster than an Arduino, which is nice when flashing often. Also, they work at 3.3V, so there's no need for level shifters. The FT2232H can also be used as an EHCI debug dongle for coreboot, which is useful when a serial port isn't available.
[1] https://review.coreboot.org/c/flashrom/+/38578 [2] https://www.velleman.eu/products/view/?id=435578 _______________________________________________ coreboot mailing list -- coreboot@coreboot.org To unsubscribe send an email to coreboot-leave@coreboot.org
Best regards,
Angel Pons