diff options
Diffstat (limited to 'util/e6400-flash-unlock/README.md')
| -rw-r--r-- | util/e6400-flash-unlock/README.md | 35 |
1 files changed, 33 insertions, 2 deletions
diff --git a/util/e6400-flash-unlock/README.md b/util/e6400-flash-unlock/README.md index 410a807a..bc9dd9f9 100644 --- a/util/e6400-flash-unlock/README.md +++ b/util/e6400-flash-unlock/README.md @@ -1,13 +1,44 @@ -# Dell Latitude E6400 Internal Flashing +# Dell Laptop Internal Flashing This utility allows you to use flashrom's internal programmer to program the entire BIOS flash chip from software while still running the original Dell -BIOS, which normally restricts software writes to the flash chip. +BIOS, which normally restricts software writes to the flash chip. It seems like +this works on any Dell laptop that has an EC similar to the SMSC MEC5035 on the +E6400, which mainly seem to be the Latitude and Precision lines starting from +around 2008 (E6400 era). ## TL;DR Run `make` to compile the utility, and then run `sudo ./e6400_flash_unlock` and follow the directions it outputs. +## Confirmed supported devices +- Latitude E6400 +- Latitude E6410 +- Latitude E4310 +- Latitude E6430 +- Precision M6800 + +It is likely that any other Latitude/Precision laptops from the same era as +devices specifically mentioned in the above list will work as Dell seems to use +the same ECs in one generation. + +## Detailed device specific behavior +- On GM45 era laptops, the expected behavior is that you will run the utility + for the first time, which will tell the EC to set the descriptor override on + the next boot. Then you will need to shut down the system, after which the + system will automatically boot up. You should then re-run the utility to + disable SMM, after which you can run flashrom. Finally, you should run the + utility a third time to reenable SMM so that shutdown works properly + afterwards. +- On 1st Generation Intel Core systems such as the E6410 and newer, run the + utility and shutdown in the same way as the E6400. However, it seems like the + EC no longer automatically boots the system. In this case you should manually + power it on. It also seems that the firmware does not set the BIOS Lock bit + when the descriptor override is set, making the 2nd run after the reboot + technically unnecessary. There is no harm in rerunning it though, as the + utility can detect when the flash is unlocked and perform the correct steps + as necessary. + ## How it works There are several ways the firmware can protect itself from being overwritten. One way is the Intel Flash Descriptor (IFD) permissions. On Intel systems, the |