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Dobrica Pavlinušić's random unstructured stuff
Chromebook: Revision 22
I have two chromebooks, one is working and one is bricked Samsung ARM Chromebook (working)localhost ~ # cat /proc/cpuinfo processor : 0 model name : ARMv7 Processor rev 4 (v7l) BogoMIPS : 48.00 Features : swp half thumb fastmult vfp edsp thumbee neon vfpv3 tls vfpv4 idiva idivt CPU implementer : 0x41 CPU architecture: 7 CPU variant : 0x0 CPU part : 0xc0f CPU revision : 4 processor : 1 model name : ARMv7 Processor rev 4 (v7l) BogoMIPS : 48.00 Features : swp half thumb fastmult vfp edsp thumbee neon vfpv3 tls vfpv4 idiva idivt CPU implementer : 0x41 CPU architecture: 7 CPU variant : 0x0 CPU part : 0xc0f CPU revision : 4 Hardware : SAMSUNG EXYNOS5 (Flattened Device Tree) Revision : 0000 Serial : 0000000000000000 localhost ~ # flashrom --flash-name flashrom v0.9.4 : 244249c : Dec 09 2016 03:49:59 UTC on Linux 3.8.11 (armv7l) flashrom v0.9.4 : 244249c : Dec 09 2016 03:49:59 UTC on Linux 3.8.11 (armv7l) vendor="Winbond" name="W25Q32DW" https://media.digikey.com/pdf/Data%20Sheets/Winbond%20PDFs/W25Q32DW.pdf localhost ~ # flashrom --get-size 4194304 localhost ~ # flashrom --wp-status WP: status: 0x00b8 WP: status.srp0: 1 WP: status.srp1: 0 WP: write protect is enabled. WP: write protect range: start=0x00000000, len=0x00200000 localhost Downloads # flashrom -r chromebook-spi.rom Block protection could not be disabled! Reading flash... SUCCESS bricked, recovery doesn't helpThis chromebook reports that it wants to do recovery, but inserting (few different) usb sticks generated using http://www.google.com/chromeos/recovery instructions doesn't help https://dl.google.com/dl/edgedl/chromeos/recovery/linux_recovery.sh archhttps://wiki.archlinux.org/index.php/Samsung_Chromebook_(ARM) setenv bootargs root=/dev/mmcblk1p2 rootfstype=jfs rootwait rw mmc dev 1 ext2load mmc 1:1 42000000 vmlinux.uimg bootm 42000000 custom firmware
dpavlin@nuc:/nuc/books/Chromebook$ wget http://commondatastorage.googleapis.com/chromeos-localmirror/distfiles/nv_uboot-snow.kpart.bz2 --2017-01-19 19:05:28-- http://commondatastorage.googleapis.com/chromeos-localmirror/distfiles/nv_uboot-snow.kpart.bz2 Resolving commondatastorage.googleapis.com (commondatastorage.googleapis.com)... 216.58.206.16, 2a00:1450:4001:820::2010 Connecting to commondatastorage.googleapis.com (commondatastorage.googleapis.com)|216.58.206.16|:80... connected. HTTP request sent, awaiting response... 200 OK Length: 281844 (275K) [application/octet-stream] Saving to: ‘nv_uboot-snow.kpart.bz2’ nv_uboot-snow.kpart.bz2 100%[================================================>] 275.24K 1.37MB/s in 0.2s 2017-01-19 19:05:28 (1.37 MB/s) - ‘nv_uboot-snow.kpart.bz2’ saved [281844/281844] This might be upstream bios update, but u-boot doesn't start at beginning, so it's probably some update format and not raw image. flash using raspberry piunplug battery before attempting this! rpi3 can power flash memory # backup root@rpi3:/home/pi/flashrom-0.9.9# ./flashrom -p linux_spi:dev=/dev/spidev0.0 -r chromeboot-bricked.rom flashrom v0.9.9-r1955 on Linux 4.4.27-v7+ (armv7l) flashrom is free software, get the source code at https://flashrom.org Calibrating delay loop... OK. Found GigaDevice flash chip "GD25LQ32" (4096 kB, SPI) on linux_spi. Unsetting lock bit(s) failed. Reading flash... done. file:///nuc/books/Chromebook/GD25LQ32_Rev1.3.pdf I repeated this twice and checked md5sum of both files to verify that I have stable connection with programmer # flash version from another chromebook root@rpi3:/home/pi# time ./flashrom-0.9.9/flashrom -p linux_spi:dev=/dev/spidev0.0 -w chromebook-spi.rom flashrom v0.9.9-r1955 on Linux 4.4.27-v7+ (armv7l) flashrom is free software, get the source code at https://flashrom.org Calibrating delay loop... OK. Found GigaDevice flash chip "GD25LQ32" (4096 kB, SPI) on linux_spi. Unsetting lock bit(s) failed. Reading old flash chip contents... done. Erasing and writing flash chip... FAILED at 0x00002000! Expected=0xff, Found=0x14, failed byte count from 0x00002000-0x00002fff: 0xfbb ERASE FAILED! Reading current flash chip contents... done. Looking for another erase function. FAILED at 0x00000000! Expected=0xff, Found=0xa3, failed byte count from 0x00000000-0x00007fff: 0x7d35 ERASE FAILED! Reading current flash chip contents... done. Looking for another erase function. FAILED at 0x00000000! Expected=0xff, Found=0xa3, failed byte count from 0x00000000-0x0000ffff: 0xfac8 ERASE FAILED! Reading current flash chip contents... done. Looking for another erase function. FAILED at 0x00000000! Expected=0xff, Found=0xa3, failed byte count from 0x00000000-0x003fffff: 0x3dea4f ERASE FAILED! Reading current flash chip contents... done. 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. Good, writing to the flash chip apparently didn't do anything. Please check the connections (especially those to write protection pins) between the programmer and the flash chip. If you think the error is caused by flashrom please report this on IRC at chat.freenode.net (channel #flashrom) or mail flashrom@flashrom.org, thanks! real 14m40.938s user 0m1.600s sys 0m9.000s # hm?! root@rpi3:/home/pi# time ./flashrom-0.9.9/flashrom -p linux_spi:dev=/dev/spidev0.0 -r chromebook-broken.rom.3 flashrom v0.9.9-r1955 on Linux 4.4.27-v7+ (armv7l) flashrom is free software, get the source code at https://flashrom.org Calibrating delay loop... OK. Found GigaDevice flash chip "GD25LQ32" (4096 kB, SPI) on linux_spi. Unsetting lock bit(s) failed. Reading flash... done. real 1m19.653s user 0m1.140s sys 0m0.700s root@rpi3:/home/pi# md5sum chromeboot-bricked.rom chromebook-broken.rom.3 1ef1d2230c27624661a86b57064057cb chromeboot-bricked.rom 1ef1d2230c27624661a86b57064057cb chromebook-broken.rom.3 # It really didn't change! ch341a attemptroot@rpi3:/home/pi# flashrom --programmer ch341a_spi -r ch341a-snow-broken-spi.rom flashrom v0.9.9-r1955 on Linux 4.4.27-v7+ (armv7l) flashrom is free software, get the source code at https://flashrom.org Calibrating delay loop... OK. Found GigaDevice flash chip "GD25LQ32" (4096 kB, SPI) on ch341a_spi. Reading flash... done. root@rpi3:/home/pi# md5sum ch341a-snow-broken-spi.rom 1ef1d2230c27624661a86b57064057cb ch341a-snow-broken-spi.rom root@rpi3:/home/pi# md5sum *.rom 1ef1d2230c27624661a86b57064057cb ch341a-snow-broken-spi.rom 11e616f5dcf18d775f6484b78953ada0 chromebook-spi.rom 1ef1d2230c27624661a86b57064057cb chromeboot-bricked.rom root@rpi3:/home/pi# time flashrom --programmer ch341a_spi -w chromebook-spi.rom flashrom v0.9.9-r1955 on Linux 4.4.27-v7+ (armv7l) flashrom is free software, get the source code at https://flashrom.org Calibrating delay loop... OK. Found GigaDevice flash chip "GD25LQ32" (4096 kB, SPI) on ch341a_spi. Reading old flash chip contents... done. Erasing and writing flash chip... Erase/write done. Verifying flash... VERIFIED. real 5m21.170s user 0m48.300s sys 0m18.330s https://dl.google.com/dl/edgedl/chromeos/recovery/linux_recovery.sh |