Re: [PATCH v4 1/7] dt-bindings: remoteproc: k3-r5f: Add Jacinto LPM memory region

["Rob Herring (Arm)" <robh@kernel.org>]

On Mon, 21 Sep 2026 16:53:19 +0200, Richard Genoud (TI) wrote:
> Declare a carveout memory region to store LPM metadata on Jacinto
> devices.
> 
> For Jacinto devices, this memory region is needed for saving ATF context
> and the certificate information of ATF and OPTEE and DM image. This LPM
> metadata area is firewalled to be accessed only by TIFS.
> 
> U-Boot R5 SPL/TIFS will use this area to save and restore:
> - ATF context
> - ATF certificate information
> - OPTEE certificate information
> - DM image (which has been copied in memory at boot time by U-Boot
> R5-SPL)
> 
> At resume, U-Boot R5 SPL is executed and detects that the board is
> resuming (with a flag set in the PMIC), then it:
> - brings out of retention the DDR
> - retrieves the LPM memory region from DTS
> - authenticates certificates from LPM memory region and applies firewalls
> - asks TIFS to restore TFA and its own minimal context
> - starts TFA on remote proc
> - loads back DM image from memory and jumps to DM
> 
> https://software-dl.ti.com/tisci/esd/latest/2_tisci_msgs/pm/lpm.html#lpm-msg-lpm-save-addr
> 
> NB: This memory region is not part of DM memory (which is not retained
> at suspend)
> 
> Signed-off-by: Richard Genoud (TI) <richard.genoud@bootlin.com>
> ---
>  .../bindings/remoteproc/ti,k3-r5f-rproc.yaml   | 18 +++++++++++++++---
>  1 file changed, 15 insertions(+), 3 deletions(-)
> 

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>