diff --git a/site/docs/build/index.md b/site/docs/build/index.md index e2c89978f362398cb7033276d965d316ac019add..d2ea655c278b29260cf9e23c536d4f732f86504c 100644 --- a/site/docs/build/index.md +++ b/site/docs/build/index.md @@ -181,121 +181,3 @@ example want to modify a config, e.g.: Or perhaps add a new board! The maintenance manual will teach you how the Libreboot build system (lbmk) works! - -Post-compilation steps -====================== - -So you compiled your Libreboot image? Congratulations! - -Before you flash, please make sure that you *dumped* two copies of the original -firmware just in case (verifying the hashes of each dump, to ensure that they -match), using the `-r` option in flashprog. - -NOTE: Libreboot standardises on [flashprog](https://flashprog.org/wiki/Flashprog) -now, as of 27 January 2024, which is a fork of flashrom. - -There are some additional considerations: - -Regarding binary blobs ----------------------- - -Firstly, you should read the Libreboot *Binary Blob Reduction Policy*: -<https://libreboot.org/news/policy.html> - -A lot of mainboards in Libreboot will boot entirely with free software, -but there are certain newer mainboards supported in Libreboot -that need binary blobs added to them, mostly for minor initialisation tasks. - -They are *automatically* inserted during the build process, but then deleted -during the *release* process; images built directly from lbmk can be flashed -without further modification, but release images need to have these files -re-inserted (e.g. KBC1126 EC firmware on HP EliteBooks). Please read this page -for context: -<https://libreboot.org/docs/install/ivy_has_common.html> - -The scripts under directory `script/vendor/` are the ones that do this. -Specifically, `script/vendor/download`. The benefit of this is that you -do not need to extract anything from the original vendor image (e.g. Lenovo -UEFI image). - -To know if this was performed on your board, you can read the Freedom Status -page which documents which files are used (if any), on which boards: -<https://libreboot.org/freedom-status.html> - -There are specific files that you must know about, so they will be covered -next: - -### Regarding CPU microcode - -Libreboot release archives provide ROMs with or without CPU microcode updates, -but the newest revisions of lbmk (from `lbmk.git`) *only* build ROM images that -contain microcode updates, by default. Libreboot's build system contains a script -that will generate release archives, and this is used to provide Libreboot -releases; this script is what provides the images with microcode removed, -alongside the default ones generated by lbmk during the build. - -Please read: -<https://libreboot.org/freedom-status.html#cpu-microcode> - -The linked page has info, and includes instructions about how to manually remove -them, if you wish to do so. Removal of CPU microcode updates (on Intel/AMD -processors) will result in unpredictable security/stability issues, so beware. - -Further context is provided in the Libreboot *Binary Blob Reduction Policy*: -<https://libreboot.org/news/policy.html> - -We *recommend* that you do not delete these updates, but you have the freedom -to choose. Additionally: we have only tested certain mainboards under this -configuration. To know which ones they are, do this in `lbmk.git`: - - cd config/coreboot/ - git grep microcode_required - -Example entry: - - e6400_4mb/target.cfg:microcode_required="n" - -If it says `="n"`, that means it has been tested. That *does not* mean it will -be stable, it's just that we're reasonably sure it will at least *boot* most -of the time, but you should expect random instability e.g. kernel panics. - -If a given mainboard *excludes* `microcode_required` in `target.cfg`, or if -it says `microcode_required="y"`, then the release ROMs will only contain -microcode updates. Manual removal (as above) is still possible, but it has -not been tested and is not recommended. - -NOTE: ARM-based chromebooks (that Libreboot supports) don't use microcode at -all. This section is only revelant for x86 (Intel/AMD). - -### Regarding Nvidia GPU ROM (Dell Latitude E6400) - -Dell Latitude E6400 comes in two variants: Nvidia graphics, or Intel graphics. -More information is available on the page: -<https://libreboot.org/docs/hardware/e6400.html> - -The intel graphics model can boot with coreboot's native video initialisation, -which is free software. The *Nvidia* model (comes with Nvidia GPU) requires -proprietary code called a *VGA Option ROM* to initialise the video display in -early boot. - -Libreboot automatically fetches this during the build process, inserting it into -the very same ROM image that can be flashed on either model, but the VGA ROM -will only be *executed* if you actually have the Nvidia *GPU* on your board. - -**ALSO: Libreboot 20230625 did not support Nvidia models at all (only Intel). -In releases, only Libreboot 20231021 and newer will support it.** - -Pre-built ROM images from release archives since 20231021 will *not* contain -this file by default, but it will be present if you compiled directly from lbmk. -To remove it, do this: - - ./cbutils/default/cbfstool libreboot.rom remove -n pci10de,06eb.rom - -The cbfstool binary was compiled when your image (target `e6400_4mb`) was -compiled, which can alter the file system within your coreboot image. - -Obviously, removing this VGA ROM will mean that the ROM image will only work -correctly on Intel GPU variants of E6400, but you probably knew that already! - -(If you're using a release archive instead, you can re-insert the VGA ROM by -following [these instructions](../install/ivy_has_common.md))