This page provides instructions for using U-Boot Falcon Mode on ADSP-SC59X boards.
It is described in the upstream repo of U-Boot: U-Boot Falcon Mode. In short, it's a way to shorten the boot time by allowing the SPL (Secondary Program Loader) to boot the kernel directly, without loading the full bootloader.
You must use Linux for ADSP-SC5xx Processors 3.0.0 or later on an SC59x board.
When following the Quickstart guides and specifically right after sourcing the setup script, i.e.
$ source setup-environment -m adsp-sc598-som-ezkit
a build folder along with a local build configuration file is created, under
$PROJECT_DIR/build/conf/local.conf. Edit this file with your favourite text editor, and append the following two lines to it:
MACHINE_FEATURES:remove = " spl" MACHINE_FEATURES:append = " falcon"
and proceed to building and flashing the image, as usual and as seen on the Quickstart guides.
When U-Boot with Falcon Mode support has been built and flashed onto the board, the default behaviour will be booting the default mode (SPI boot, if unchanged) straight from the SPL, e.g.:
U-Boot SPL 2020.10 (Apr 12 2023 - 18:48:14 +0000) ADI Boot Mode: 0x1 (QSPI Master) Trying to boot from SPI ## Loading kernel from FIT Image at 96000000 ... Using 'conf-1' configuration Verifying Hash Integrity ... OK Trying 'kernel-1' kernel subimage Verifying Hash Integrity ... sha1+ sha1,rsa2048:dev- OK Loading kernel from 0x960000e0 to 0x9a200000 Uncompressing Kernel Image ## Loading ramdisk from FIT Image at 96000000 ... Using 'conf-1' configuration Verifying Hash Integrity ... OK Trying 'ramdisk-3' ramdisk subimage Verifying Hash Integrity ... sha1+ sha1,rsa2048:dev- OK Loading ramdisk from 0x965a1e50 to 0x9c000000 ## Loading fdt from FIT Image at 96000000 ... Using 'conf-1' configuration Verifying Hash Integrity ... OK Trying 'fdt-2' fdt subimage Verifying Hash Integrity ... sha1+ sha1,rsa2048:dev- OK Loading fdt from 0x9659ac00 to 0x99000000 [ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x412fd050] [ 0.000000] Linux version 5.15.78-yocto-standard (oe-user@oe-host) (aarch64-poky-linux-musl-gcc (GCC) 11.2.0, GNU ld (GNU Binutils) 2.38.20220313) #1 SMP PREEMPT Wed Apr 12 17:53:07 UTC 2023 [ 0.000000] Machine model: ADI 64-bit SC598 SOM EZ Kit [ 0.000000] earlycon: adi_uart0 at MMIO 0x0000000031003000 (options '') [ 0.000000] printk: bootconsole [adi_uart0] enabled [ 0.000000] efi: UEFI not found.
You will then be able to use the full U-Boot:
U-Boot SPL 2020.10 (Apr 12 2023 - 18:48:14 +0000) Pushbutton helding during boot -- entering U-Boot ProperADI Boot Mode: 0x1 (QSPI Master) Trying to boot from BOOTROM U-Boot 2020.10 (Apr 12 2023 - 18:48:14 +0000) CPU: ADSP ADSP-SC598-0.0 (spi slave boot) Model: ADI sc598-som-ezkit DRAM: 224 MiB WDT: Not found! MMC: mmc@310C7000: 0 Loading Environment from SPIFlash... SF: Detected is25lp512 with page size 256 Bytes, erase size 64 KiB, total 64 MiB OK In: serial@0x31003000 Out: serial@0x31003000 Err: serial@0x31003000 Net: eth0: eth0 Hit any key to stop autoboot: 0