| This directory contains examples of the new-style BIOS bitmaps, and a simple |
| (and ugly) tool to view the configuration file that describes how each |
| screen is displayed. |
| |
| Old-style bitmaps: |
| |
| In the Cr-48 BIOS there are four BIOS screens that may be presented to the |
| user. Each contains a graphic, a URL, and some informative text. The screens |
| are single bitmap images, hardcoded in read-only BIOS (because they have to |
| display even when the R/W BIOS and SSD are both completely erased). They can |
| be replaced at manufacturing time, but creating the screens is difficult. |
| The format is a compressed EFI firmware volume that is generated when the |
| BIOS is compiled. The result is an opaque blob that cannot be viewed or |
| edited with linux-based tools. |
| |
| |
| New-style bitmaps: |
| |
| Future BIOSes will continue to display the same basic screens, but using a |
| different format. Each screen will have separate bitmaps for the basic |
| graphic, the URL, and the informative text, and will be displayed by |
| rendering each component in order. This will allow us to modify and replace |
| any bitmap (most frequently the HWID), using standard command-line tools |
| such as imagemagick. Compositing each screen in this way also means that we |
| can easily provide localized BIOS screens or custom messages. |
| |
| |
| Note: |
| |
| Because the bitmap images and display code is part of the Read-Only BIOS, |
| back-porting the new-style bitmaps to older devices is not possible. |
| |
| |
| Instructions: |
| |
| The bmpblk_utility reads a config file and produces a binary bmpblock. The |
| config file lists the individual bitmaps and describes where to place each |
| one when displaying each screen. The bmpblock is then written into the BIOS |
| image with the gbb_utility. The bitmap_viewer program lets you view the |
| composited screens as described by the config file. |
| |
| * First, get the bitmap_viewer working. This is best used OUTSIDE of the |
| chroot. Test it by changing to the scripts/newbitmaps/images/1280x800 |
| directory and running "../../bitmap_viewer unknown.yaml". You may need to |
| install some additional packages. For example, on Ubuntu you'll probably |
| need to install the "python-yaml" and "python-wxgtk2.8" packages. |
| |
| * Now make changes to the unknown.yaml config file, and use the |
| bitmap_viewer to see how the layout looks. Hit Ctrl-R in the small window |
| to reload the config file without restarting. |
| |
| * The bitmap_viewer can display images in several different formats, but the |
| BIOS is very limited (and may differ between x86 and ARM). For x86, ensure |
| that you're using the proper format by converting any new bitmaps with a |
| command like this: |
| |
| convert IN.bmp -colors 256 -compress none -alpha off OUT.bmp |
| |
| * When you have the screens tweaked to your satisfaction, generate the |
| binary bmpblock to embed into the BIOS. |
| |
| bmpblk_utility -c unknown.yaml bmpblock.bin |
| |
| * Use the gbb_utility to modify the BIOS to contain our new set of bitmaps. |
| |
| NOTE: These commands are run (as root) on the device under test! |
| |
| NOTE: This will only work if the BIOS write-protection is disabled! |
| |
| Copy our new bmpblock over. |
| |
| cd /mnt/stateful_partition |
| scp USER@SOMEHOST:/SOMEPATH/bmpblock.bin . |
| |
| Get a copy of the current BIOS. |
| |
| flashrom -r bios.bin |
| |
| Put our bmpblock in our copy of the BIOS |
| |
| gbb_utility -s -b bmpblock.bin bios.bin |
| |
| Reflash the BIOS with the new content |
| |
| flashrom -w bios.bin |
| |
| * Reboot. You should see your new bitmaps appear whenever the BIOS screens |
| are displayed. If you have more than one localization, you should be able |
| to cycle among them with the arrow keys. |
| |
| * If you want to examine a binary bmpblock that you've pulled from a BIOS |
| image, the bmpblk_utility has options to display or unpack the binary. |
| |
| bmpblk_utility bmpblock.bin |
| |
| bmpblk_utility -y bmpblock.bin |
| |
| bmpblk_utility -x -d /SOME/SCRATCH/DIR bmpblock.bin |