You probably didn't connect all pins of the flash chip. You have to pull /HOLD and /WP high (connect them to 3V3, preferably through some resistor) to succeed.

Hi Marius,
A few days ago Nico suggested for a similar issue the
        following:
You probably didn't connect all pins of the flash chip. You have to
   pull /HOLD and /WP high (connect them to 3V3, preferably through some
   resistor) to succeed.

Best regards,
Miklos Marton

Hi,

??I recently bought two VMAC V1 Mini PC's with Winbond W25Q64FWSIG EFI chips. Updating the EFI information on teh devices using the normal software route is extremely flakey and I managed to corrupt the EFI on both boards, making them unbootable.

I now have a Chinese CH341a ("Black Edition") usb programmer and a "piggy-back" 1.8v adapter and can connect to the Winbond chip using a test clip.

I installed flashrom from the debian package V0.99 and can do a:

Initially, I thought I had problems getting?the?clip properly seated, but no matter?how much I clean the contacts and re-seat the clip, if I do a:
?#flashrom -p ch341a_spi -V

I get (randomly):
Found Winbond flash chip "unknown Winbond (ex Nexcom) SPI chip" (0 kB, SPI) on ch341a_spi.
Found Generic flash chip "unknown SPI chip (RDID)" (0 kB, SPI) on ch341a_spi.
Found Winbond flash chip "W25Q64.W" (8192 kB, SPI) on ch341a_spi.

Finding the correct chip or not seems to have little or nothing to do with the physical contact to the chip.
If I then try to erase the chip. I get:

? # flashrom -p ch341a_spi -c W25Q64.W -E
flashrom v0.9.9-r1954 on Linux 4.10.1-towo.1-siduction-amd64 (x86_64)
flashrom is free software, get the source code at https://flashrom.org

Calibrating delay loop... OK.
Found Winbond flash chip "W25Q64.W" (8192 kB, SPI) on ch341a_spi.
Erasing and writing flash chip... FAILED at 0x00000000! Expected=0xff, Found=0x00, failed byte count from 0x00000000-0x00000fff: 0x1000
ERASE FAILED!
Reading current flash chip contents... done. Looking for another erase function.
FAILED at 0x00000000! Expected=0xff, Found=0x00, failed byte count from 0x00000000-0x00007fff: 0x53cb
ERASE FAILED!
Reading current flash chip contents... done. Looking for another erase function.
FAILED at 0x00000000! Expected=0xff, Found=0xd6, failed byte count from 0x00000000-0x0000ffff: 0x9264
ERASE FAILED!
Reading current flash chip contents... done. Looking for another erase function.
FAILED at 0x00000000! Expected=0xff, Found=0x00, failed byte count from 0x00000000-0x007fffff: 0x5e1391
ERASE FAILED!
Reading current flash chip contents... done. Looking for another erase function.
FAILED at 0x00000000! Expected=0xff, Found=0x00, failed byte count from 0x00000000-0x007fffff: 0x5ce187
ERASE FAILED!
Looking for another erase function.
No usable erase functions left.
FAILED!
Your flash chip is in an unknown state.
Please report this on IRC at chat.freenode.net (channel #flashrom) or
mail flashrom@flashrom.org, thanks!

Again, the hex codes for the failures seem pretty random and are different each time I try the command.

I attach the log.

??Can anyone say what's going on?

?Best Regards

Marius

End of flashrom Digest, Vol 100, Issue 15
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