U-Boot and legacy SPL power control on modern platforms

[Peng Fan]

Hi Simon, Tom

On Wed, Mar 25, 2026 at 11:56:25AM -0600, Simon Glass wrote:
>Hi,
>
>On Wed, 25 Mar 2026 at 10:52, Tom Rini <trini at konsulko.com> wrote:
>>
>> On Wed, Mar 25, 2026 at 07:18:56PM +0800, Peng Fan wrote:
>> > Hi Tom,
>> >
>> > On Fri, Mar 20, 2026 at 03:45:18PM -0600, Tom Rini wrote:
>> > >Hello,
>> > >
>> > >As part of the work I've been doing on clarifying Kconfig dependencies
>> > >I've stumbled on to a number of modern boards[1] that are using the
>> > >SPL_POWER_LEGACY symbol. Can the maintainers please update these to use
>> > >DM_PMIC, DM_REGULATOR (and SPL variants) as needed so that they use the
>> > >modern architecture, or let me know what's missing here? Thanks!
>> >
>> > For i.MX8MQ, I think we may need to leave with SPL_POWER_LEGACY,
>> > the board has 256KB TCM, but u-boot-spl-ddr.bin is almost using all
>> > of them if enabling SPL_DM, other SPL_OF_CONTROL and other DM drivers.
>> >
>> > u-boot-spl.bin itself is 90KB+, but ddr firmware and hdmi.bin are packed
>> > in u-boot-spl-ddr.bin, the image is a bit large.
>>
>> Ugh. Does CONFIG_SPL_OPTIMIZE_INLINING=y win us enough space here to
>> matter? Changing CONFIG_SPL_LOGLEVEL rarely is enough of a win to
>> matter, so I don't think that'll help. Turning off CONFIG_MMC_VERBOSE
>> sometimes helps, but only a little.
>>
>> If we really can't make it all fit, then renaming some options needs to
>> be done once we remove the legacy portion from full U-Boot (of which
>> there's a much smaller number of semi-modern platforms enabling it).
>> Thanks for checking on this.
>
>It is pretty ugly, but there is of-platdata

I will give some try to see if we could save some time, whether using
of-platdata, turn off mmc verbose or else.

Thanks,
Peng

>
>Regards,
>Simon