On 19/12/2024 08:43, Siddharth Vadapalli wrote: > On Wed, Dec 18, 2024 at 04:08:01PM +0200, Roger Quadros wrote: > > Hello Roger, > >> >> >> On 18/12/2024 14:45, Siddharth Vadapalli wrote: > > [...] > >>> +DFU based boot >>> +-------------- >>> + >>> +To boot the board over DFU, set the switches to DFU mode and connect to the >>> +USB type C DRD port on the board. After power-on the build artifacts needs >>> to be >>> +uploaded one by one with a tool like dfu-util. >>> + >>> +The initial ROM will have a DFU alt named `bootloader` for the initial R5 >>> spl >>> +upload. The next stages as exposed by U-Boot have target alts matching the >>> name >>> +of the artifacts, for these a USB reset has to be done after each upload. >>> + >>> +When using dfu-util the following commands can be used to boot to a U-Boot >>> shell: >>> + >>> +.. prompt:: bash $ >>> + >>> + dfu-util -a bootloader -D tiboot3.bin >>> + dfu-util -R -a tispl -D tispl.bin >>> + dfu-util -R -a u-boot.img -D u-boot.img >> >> Is there a known reason why -R was not used for the first command but >> required in last two? >> What about if -R is not used for all 3 commands? > > According to the "dfu-util" help menu, the "-R" option is defined as: > "Issue USB Reset signalling once we're finished" > > While the "-R" option is not required in the first stage / command, it > is required in the next stages. Without "-R", the user would have to > press "Ctrl+C" to proceed i.e. tispl.bin / u-boot.img are transferred > / downloaded onto the device but not executed until user presses "Ctrl+C". > > As to why "-R" is not required in the first stage, I suppose that ROM > automatically executes tiboot3.bin after it has been transferred. >
Thanks Siddharth for the clarification. -- cheers, -roger
