Hi Heinrich, On Fri, 3 Jan 2025 at 12:55, Heinrich Schuchardt <[email protected]> wrote: > > On 06.12.24 18:30, Adriano Cordova wrote: > > The command bootefi calls efi_init_obj_list to do the efi set up > > before launching an .efi payload, but efi_init_obj_list is called > > only once. There are some initializations which depend on the > > environment and should be done each time a payload gets launched and > > not only once and can now be done in efi_start_obj_list(). A motivation > > for this change is the following order of events: > > > > 1. Launch an EFI application (e.g. bootefi hello) > > 2. Change the ip address > > 3. Launch another application which uses the pxe protocol > > Hello Adriano, > > Thanks for addressing this issue. > > There are a number of events that can lead to updating the IP address: > > * EFI_PXE_BASE_CODE_PROTOCOL.Dhcp() > * EFI_PXE_BASE_CODE_PROTOCOL.SetStationIp() > * EFI_HTTP_PROTOCOL.Configure() > * command set env ethaddr# > * command dhcp > > All of these events require: > > * Updating the relevant ethaddr* variable. > * Updating any other references to the IP address. > > When not only considering EFI applications but also EFI drivers > installed via the bootefi command all of these events can occur during > the runtime of EFI binaries. > > Function efi_init_obj_list() is used for setups that are needed only > once before accessing the UEFI sub-system. It is not able to handle events. > > If we need to update any internal UEFI data structures, we should do > this instantaneously when the event occurs and not when executing a UEFI > related shell command. > > U-Boot already has callbacks invoked when variables are changed. These > are set up with U_BOOT_ENV_CALLBACK(). There is even a command 'env > callbacks' to list these callbacks. > > You could define a new function to handle changes of the IP address and > invoke it via U_BOOT_ENV_CALLBACK(ipaddr, <function name>) or > U_BOOT_ENV_CALLBACK(netmask, <function name>). > > With lwIP we can have multiple network interfaces. Each has a different > variable ipaddr# assigned to it. We will have to extend the concept of > U_BOOT_ENV_CALLBACK() to allow for wildcard matches by adjusting > find_env_callback(). With CONFIG_REGEX=y regular expressions could be > used for this purpose (cf. include/slre.h) but we should better avoid > the code size increase. >
I have been saying for some time that EFI_LOADER should make use of U-Boot's existing tables, rather than creating its own duplicate ones with extra info. This seems to have been understood as 'hang the EFI tables onto existing data structures', e.g. efi_disk_create_part(). But this leads to duplication. Perhaps the EFI_LOADER init should be quite small, and be done each time an app starts, to deal with the 'current' state of U-Boot? Regards, Simon
