U-Boot and legacy SPL power control on modern platforms

[Simon Glass]

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

Regards,
Simon