[PATCHv3 2/6] lmb: add LMB_FDT for fdt reserved regions

[Randolph Sapp]

On Thu Apr 16, 2026 at 4:02 PM CDT, Simon Glass wrote:
> Hi Randolph,
>
> On Tue, 14 Apr 2026 at 08:36, <rs at ti.com> wrote:
>>
>> From: Randolph Sapp <rs at ti.com>
>>
>> Add an LMB_FDT bit for fdt reserved regions, so we can reclaim them when
>> parsing a new device tree and properly warn people when a reservation
>> overlaps with an existing allocation.
>>
>> If we don't at least warn the user of these reservation failures,
>> there's a chance that this region could be freed and reallocated for
>> something important later.
>>
>> This useful warning mechanism was broken in:
>> 5a6aa7d5913 ("boot: fdt: Handle already reserved memory in boot_fdt_reserve_region()")
>>
>> Signed-off-by: Randolph Sapp <rs at ti.com>
>> ---
>>  boot/image-fdt.c |  5 ++++-
>>  include/lmb.h    | 14 ++++++++++++++
>>  lib/lmb.c        | 33 +++++++++++++++++++++++++++++----
>>  3 files changed, 47 insertions(+), 5 deletions(-)
>>
>
> With bootstd we maintain a list of images attached to each bootflow,
> including the address when loaded. Could that provide a solution here?
>
> Regards,
> Simon

Hey Simon, you may have to elaborate on that a little more. Are you suggesting
we treat FDT reserved regions as dummy bootstd binary entries? That might work
if it counts as an LMB reservation and we can dynamically update it if the FDT
is reloaded/changed. I haven't looked into that too much yet.