mailbox: mpfs-mbox: support new syscon based devicetree configuration

The original PolarFire SoC mailbox devicetree bindings described the
control/status and interrupt registers as standalone reg regions of the
mailbox device. This was incorrect, as these registers are shared system
control blocks and should instead be modeled as syscon devices.

Linux has since corrected this by introducing syscon-based bindings for
the MPFS mailbox and updating the mailbox driver to access the control
and interrupt registers via syscon/regmap. U-Boot, however, continued to
expect the legacy binding, causing mailbox access to fail when using
Linux-aligned devicetrees.

Update the U-Boot MPFS mailbox driver to support the new syscon-based
bindings by resolving the control and sysreg syscon nodes and accessing
the registers through regmap. Support for the legacy mailbox binding is
retained for backwards compatibility with existing firmware-provided
devicetrees.

This brings the U-Boot mailbox driver in line with the corrected hardware
description and matches the behavior of the Linux mailbox driver.

Signed-off-by: Jamie Gibbons <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>

0 files changed, 0 insertions, 0 deletions