Re: [PATCH v3 0/7] arm64: dts: ti: k3-am62a7-sk: Split r5f memory region

Vignesh Raghavendra
2026-04-09T09:46:52Z

Hi Markus

On 08/04/26 20:33, Rob Herring wrote:
> On Wed, Mar 18, 2026 at 10:14 AM Markus Schneider-Pargmann (TI)
> <msp@baylibre.com> wrote:
>>
>> Hi,
>>
>> Split the firmware memory region in more specific parts so it is better
>> described where which information is stored. Specifically the LPM metadata
>> region is important as bootloader software like U-Boot has to know where
>> that data is to be able to read that data and resume from RAM.
>>
>> IO+DDR is a deep sleep state in which a few pins are set to be sensitive
>> for wakeup while the DDR is kept in self refresh. Everything else is
>> powered off.
>>
>> The changes in this series were suggested as part of the IO+DDR u-boot series:
>> https://lore.kernel.org/r/814c211f-a9eb-4311-bb84-165b1a69755f@ti.com
>>
>> There are currently no real users of the memory-region that is split in
>> this series. The size of the memory-region in total stays the same.
>> The new layout is derived from the software running on the r5f
>> processor:
>> https://github.com/TexasInstruments/mcupsdk-core-k3/blob/k3_main/examples/drivers/ipc/ipc_rpmsg_echo_linux/am62ax-sk/r5fss0-0_freertos/ti-arm-clang/linker.cmd#L172
>> https://github.com/TexasInstruments/mcupsdk-core-k3/blob/k3_main/source/drivers/device_manager/sciclient.h#L459
>>
>> Additionally the two important devicetree nodes for resuming from IO+DDR
>> have the bootph-pre-ram flag added as this data needs to be read before
>> the RAM is in use.
>>
>> Best
>> Markus
>>
>> Signed-off-by: Markus Schneider-Pargmann (TI) <msp@baylibre.com>
>> ---
>> Changes in v3:
>> - Squash the enforcement of the memory-region-names requirement in the
>> patch adding the memory-region-names, as suggested.
>> - Link to v2: https://lore.kernel.org/r/20260312-topic-am62a-ioddr-dt-v6-19-v2-0-37cb7ceec658@baylibre.com
>>
>> Changes in v2:
>> - Make memory-region-names required if memory-region is present
>> - Fixup memory-region and memory-region-names conditions. Require either
>> 2 or 6 regions for memory-region and memory-region-names
>> - Reword and restructure the binding documentation for memory-region and
>> memory-region-names
>> - Add memory-region-names to all uses of memory-region
>> - Link to v1: https://lore.kernel.org/r/20260303-topic-am62a-ioddr-dt-v6-19-v1-0-12fe72bb40d2@baylibre.com
>>
>> ---
>> Markus Schneider-Pargmann (TI) (7):
>> dt-bindings: remoteproc: k3-r5f: Split up memory regions
>> dt-bindings: remoteproc: k3-r5f: Add memory-region-names
>> arm64: dts: ti: k3: Use memory-region-names for r5f
>> arm64: dts: ti: k3-am62a7-sk: Split r5f memory region
>> arm64: dts: ti: k3-am62p5-sk: Split r5f memory region
>> arm64: dts: ti: k3-am62a7-sk: Add r5f nodes to pre-ram bootphase
>> arm64: dts: ti: k3-am62p5-sk: Add r5f nodes to pre-ram bootphase
>
> TI folks, Please make sure these dts patches are picked up for 7.1.
> There's now a crap load of warnings in next with the binding change:
>
> 58 (ti,am62-r5fss): r5f@78000000: 'memory-region-names' is a
> required property

[...]

> If they aren't applied, making 'memory-region-names' required needs
> to be dropped from the binding.
>

This breaks DT backward compatibility. Why is memory-region-names now a
required item and cannot be assumed as "dma" and "firmware" as default?
Is that intentional (should have at least had a Fixes tag then if the
original definition was wrong)?

--
Regards
Vignesh