Hi, I'm trying to flash the rom of a bricked Chromebook. I've tried multiple times, removing and reattaching the ch341a. The rom chip is still attached to the motherboard (I've never soldered). Any help would be appreciated! Thanks, Jen
jen@localhost:~> sudo ./flashrom -p ch341a_spi -w coreboot_tiano-candy-mrchromebox_20220704.rom flashrom v1.2-99-gfbb2b25f61 on Linux 5.14.21-150400.24.11-default (x86_64) flashrom is free software, get the source code at https://flashrom.org
Using clock_gettime for delay loops (clk_id: 1, resolution: 1ns). Found Winbond flash chip "W25Q64.W" (8192 kB, SPI) on ch341a_spi. Reading old flash chip contents... done. Erasing and writing flash chip... FAILED at 0x0000ef66! Expected=0xff, Found=0xfb, failed byte count from 0x0000e000-0x0000efff: 0x1 ERASE FAILED! Reading current flash chip contents... done. Looking for another erase function. FAILED at 0x00004de1! Expected=0xff, Found=0xf7, failed byte count from 0x00000000-0x00007fff: 0x3 ERASE FAILED! Reading current flash chip contents... done. Looking for another erase function. FAILED at 0x0000561e! Expected=0xff, Found=0x7f, failed byte count from 0x00000000-0x0000ffff: 0x2 ERASE FAILED! Reading current flash chip contents... done. Looking for another erase function. FAILED at 0x00008b98! Expected=0xff, Found=0xfe, failed byte count from 0x00000000-0x007fffff: 0x1f9 ERASE FAILED! Reading current flash chip contents... done. Looking for another erase function. FAILED at 0x0000aa4b! Expected=0xff, Found=0xfe, failed byte count from 0x00000000-0x007fffff: 0x444 ERASE FAILED! Reading current flash chip contents... done. Looking for another erase function. Looking for another erase function. Looking for another erase function. No usable erase functions left. FAILED! Uh oh. Erase/write failed. Checking if anything has changed. Reading current flash chip contents... done. Apparently at least some data has changed. Your flash chip is in an unknown state.
Hello Jen,
On 31.07.22 21:03, Jen Gilbert wrote:
Hi, I'm trying to flash the rom of a bricked Chromebook. I've tried multiple times, removing and reattaching the ch341a. The rom chip is still attached to the motherboard (I've never soldered). Any help would be appreciated!
it looks like your connection to the SPI chip is just a little flaky. Every time flashrom fails to read 0xff, only a single 1 bit is missing (i.e. 0xfb: bit 2 is missing; 0xf7: bit 3 is missing etc.). Also, if you look at the erased ranges, you'll see that some errors actually vanished:
failed byte count from 0x00000000-0x00007fff: 0x3 failed byte count from 0x00000000-0x0000ffff: 0x2
So it seems reading is unreliable. But erasing works fine, writing should too (but might also suffer from bit flips).
What you can do to enhance signal quality:
* Use shorter cables. <=20cm is recommended, sometimes <=10cm helps. * Add series resistors to the data/control lines (MOSI, MISO, CS, CLK).
Hope that helps, Nico
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Jen Gilbert -
Nico Huber