[PATCH v4 0/2] remoteproc: add AMD BRAM-based remote processor driver

[Ben Levinsky <ben.levinsky@amd.com>]

Add a BRAM-based remoteproc driver and corresponding binding for AMD
soft processors located in programmable logic.

The series models a soft-core processor subsystem that executes firmware
from dual-port BRAM. The BRAM window is described in the processor-local
address space and translated to the Linux-visible system physical address
through the parent bus ranges property.

This series depends on the remoteproc cleanup series available here:

  https://lore.kernel.org/linux-remoteproc/ah2aVdlsLqy9aeHP@p14s/

That series adds the common WC ioremap carveout callbacks and optional
ELF resource-table helper used by patch 2.

v4:
  Patch 1, dt-bindings: remoteproc: document AMD BRAM-based rproc

  - Sorted the SoC-specific compatible enum by name.

  Patch 2, remoteproc: add AMD BRAM-based remote processor driver

  - Dropped the driver-specific MAINTAINERS entry.
  - Trimmed the Kconfig help text.
  - Reused the common WC ioremap/iounmap carveout callbacks.
  - Reused the common optional ELF resource-table helper.
  - Used resource_size(&res) for the translated memory window size.
  - Kept the coredump segment address as the processor-local device
    address. The coredump path resolves segment addresses through
    rproc_da_to_va() against the registered carveout device address, while
    res.start is the Linux-visible system physical address after DT
    translation and may differ from the processor-local BRAM address.

v3:
  This version updates the binding to use SoC-specific compatibles with
  the fallback form discussed on the thread.

  Patch 1, dt-bindings: remoteproc: document AMD BRAM-based rproc

  - Reworked the compatible schema to use SoC-specific compatibles.
  - Added amd,versal2-bram-rproc to the supported compatible list.
  - Used xlnx,zynqmp-bram-rproc as the fallback compatible.
  - Updated the example to match the new compatible scheme.

  Patch 2, remoteproc: add AMD BRAM-based remote processor driver

  - Updated the driver OF match table to bind via the
    xlnx,zynqmp-bram-rproc fallback compatible.

v2:
  This version pivots the series away from a MicroBlaze-specific binding
  and driver shape and instead models a BRAM-based soft-core processor
  subsystem more generally.

  This follows the upstream feedback that amd,microblaze was too tied to
  the processor architecture while also being too generic as a DT
  compatible for the hardware interface being described.

  Patch 1, dt-bindings: remoteproc: document AMD BRAM-based rproc

  - Renamed the binding away from amd,microblaze and reframed it around a
    BRAM-based soft-core processor subsystem.
  - Dropped the redundant trailing "binding" wording from the patch
    subject.
  - Rewrote the binding text to describe the hardware rather than the Linux
    remoteproc framework.
  - Reworked the example to address the original dt_binding_check
    complaints about the root node and simple-pm-bus example shape.
  - Added a clocks property for the soft-core subsystem.

  Patch 2, remoteproc: add AMD BRAM-based remote processor driver

  - Renamed the driver away from the MicroBlaze-specific name to match the
    BRAM-based binding.
  - Added clock handling for the soft-core subsystem and the matching
    COMMON_CLK dependency in Kconfig.
  - Cleaned up the reset comments and removed the success dev_dbg() message
    called out in review.

Ben Levinsky (2):
  dt-bindings: remoteproc: document AMD BRAM-based rproc
  remoteproc: add AMD BRAM-based remote processor driver

 .../bindings/remoteproc/amd,bram-rproc.yaml   | 105 +++++++++
 drivers/remoteproc/Kconfig                    |  11 +
 drivers/remoteproc/Makefile                   |   1 +
 drivers/remoteproc/amd_bram_rproc.c           | 213 ++++++++++++++++++
 4 files changed, 330 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/remoteproc/amd,bram-rproc.yaml
 create mode 100644 drivers/remoteproc/amd_bram_rproc.c

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2.34.1