t60_unbrick.md 9.0 KB
title: ThinkPad T60 Recovery guide x-toc-enable: true ...
This section documents how to recover from a bad flash that prevents your ThinkPad T60 from booting.
This section documents how to recover from a bad flash that prevents your ThinkPad X60 from booting.
ROM images for this machine are well-tested in osboot, so bricks are rare. The most common cause of a brick is operator error, when flashing a ROM image. In most cases, the cause will be that there is no bootblock, or an invalid one.
Brick type 1: bucts not reset. {#bucts_brick}
You still have Lenovo BIOS, or you had osboot running and you flashed another ROM; and you had bucts 1 set and the ROM wasn't dd'd.* or if Lenovo BIOS was present and osboot wasn't flashed.
There are 2 64KiB bootblocks possible, in the upper part of the ROM image. By default (bucts set to 0), the top one is used. If bucts is set to 1, the lower one (the one before the top one) is used. This bootblock is the first code that executes, during romstage as per coreboot hardware initialization.
BUC is short for Backup Control and TS is short for Top Swap. This is a special register on Intel platforms. Lenovo BIOS sets PRx registers, preventing software re-flashing, but there is a bug in the protection, allowing everything except the upper 64KiB from being flashed. By default, coreboot only puts a bootblock in the upper region. If you flash such a ROM, while bucts is set to 1, the system won't boot because there's not a valid bootblock; this is common if you're re-flashing when coreboot is already installed, and you didn't set bucts back to 0.
When you install on X60/T60 the first time, you set this bucts bit to 1, then you re-flash a second time and set it back to 0.
In this case, unbricking is easy: reset BUC.TS to 0 by removing that
yellow cmos coin (it's a battery) and putting it back after a minute or
two:\
*Those dd commands should be applied to all newly compiled T60 ROM images (the ROM images in osboot binary archives already have this applied!):
dd if=coreboot.rom of=top64k.bin bs=1 skip=$[$(stat -c %s coreboot.rom) - 0x10000] count=64k
dd if=coreboot.rom bs=1 skip=$[$(stat -c %s coreboot.rom) - 0x20000] count=64k | hexdump
dd if=top64k.bin of=coreboot.rom bs=1 seek=$[$(stat -c %s coreboot.rom) - 0x20000] count=64k conv=notrunc
(doing this makes the ROM suitable for use when flashing a system that still has Lenovo BIOS running, using those instructions: http://www.coreboot.org/Board:lenovo/x60/Installation. (it says x60, but instructions for t60 are identical)
Brick type 2: bad ROM image {#recovery}
In this instance, you might have flashed a ROM without the top bootblock copied to the lower 64KiB section in the ROM, and you flashed the ROM for the first time (from Lenovo BIOS), in which case there is not a valid bootblock.
In this scenario, you compiled a ROM that had an incorrect configuration, or there is an actual bug preventing your system from booting. Or, maybe, you set BUC.TS to 0 and shut down after first flash while Lenovo BIOS was running. In any case, your system is bricked and will not boot at all.
"Unbricking" means flashing a known-good (working) ROM. The problem: you can't boot the system, making this difficult. In this situation, external hardware (see hardware requirements above) is needed which can flash the SPI chip (where osboot resides).
Remove those screws and remove the HDD:\
Lift off the palm rest:\
Lift up the keyboard, pull it back a bit, flip it over like that and
then disconnect it from the board:\
Gently wedge both sides loose:\
Remove that cable from the position:\
Now remove that bezel. Remove wifi, nvram battery and speaker connector
(also remove 56k modem, on the left of wifi):\
Remove those screws:\
Disconnect the power jack:\
Remove nvram battery:\
Disconnect cable (for 56k modem) and disconnect the other cable:\
Disconnect speaker cable:\
Disconnect the other end of the 56k modem cable:\
Make sure you removed it:\
Unscrew those:\
Make sure you removed those:\
Disconnect LCD cable from board:\
Remove those screws then remove the LCD assembly:\
Once again, make sure you removed those:\
Remove the shielding containing the motherboard, then flip it over. Remove these screws, placing them on a steady surface in the same layout as they were in before you removed them. Also, you should mark each screw hole after removing the screw (a permanent marker pen will do), this is so that you have a point of reference when re-assembling the system:
This photo shows the flash chip, near the RAM, with numbers of pins written:
Refer to the external flashing guide:
Externally rewrite 25xx NOR flash via SPI protocol
NOTE: Do not use the 3.3v rail from your SPI programmer. Leave that disconnected. For 3.3v, plug your charger into the mainboard (but do not power on the mainboard) when the clip is connected. Before removing the clip, disconnect the charger. This will provide adequate 3.3v DC at correct current levels. The SPI flash on an X60 shares a common 3.3V rail with many other components on the mainboard, which all draw a lot of current, more than your flasher can provide.
Example command:
sudo ./flashrom -p linux_spi:dev=/dev/spidev0.0,spispeed=4096 -w osboot.rom -V
If flashrom complains about multiple flash chips detected, just pass the -c
option as it suggests, and pick any of the chips it lists. spispeed=4096 or
lower (e.g. spispeed=512) is recommended on this board. The flashing becomes
unstable, on this machine, when you use higher speeds.
Reverse the steps to re-assemble your system, after you've flashed the chip.
It should be Verifying flash... VERIFIED at the end. If flashrom
complains about multiple flash chip definitions detected, then choose
one of them following the instructions in the output.
Put those screws back:\
Put it back into lower chassis:\
Attach LCD and insert screws (also, attach the lcd cable to the board):\
Insert those screws:\
On the CPU (and there is another chip south-east to it, sorry forgot to
take pic) clean off the old thermal paste (with the alcohol) and apply
new (Artic Silver 5 is good, others are good too) you should also clean
the heatsink the same way\
Attach the heatsink and install the screws (also, make sure to install
the AC jack as highlighted):\
Reinstall that upper bezel:\
Do that:\
Re-attach modem, wifi, (wwan?), and all necessary cables. Sorry, forgot to take pics. Look at previous removal steps to see where they go back to.
Attach keyboard and install nvram battery:\
Place keyboard and (sorry, forgot to take pics) reinstall the palmrest
and insert screws on the underside:\
It lives!\
Always stress test ('stress -c 2' and xsensors. below 90C is ok) when
replacing cpu paste/heatsink:\
