On 4/28/26 11:14, Krzysztof Kozlowski wrote:
On 28/04/2026 11:04, Michal Simek wrote:
On 4/28/26 10:47, Krzysztof Kozlowski wrote:
On 28/04/2026 10:33, Michal Simek wrote:
On 4/28/26 08:50, Krzysztof Kozlowski wrote:
On Mon, Apr 27, 2026 at 09:27:02AM -0700, Ben Levinsky wrote:
Describe an AMD BRAM-based soft-core processor subsystem instantiated in
programmable logic and using dual-port BRAM for firmware storage and
execution.
The binding models a soft-core processor subsystem instantiated in AMD
programmable logic and using dual-port BRAM for firmware storage and
execution. The remoteproc device is represented as a child node whose
reg property describes the firmware memory window in the processor-local
address space. The parent bus node provides standard devicetree address
translation through ranges so Linux can access the same BRAM through the
system physical address space.
A clock input feeds the soft-core processor subsystem, and an active-low
reset GPIO holds the processor in reset until firmware loading
completes. The firmware-name property is optional.
Signed-off-by: Ben Levinsky <[email protected]>
---
.../bindings/remoteproc/amd,bram-rproc.yaml | 98 +++++++++++++++++++
1 file changed, 98 insertions(+)
create mode 100644
Documentation/devicetree/bindings/remoteproc/amd,bram-rproc.yaml
diff --git a/Documentation/devicetree/bindings/remoteproc/amd,bram-rproc.yaml
b/Documentation/devicetree/bindings/remoteproc/amd,bram-rproc.yaml
new file mode 100644
index 000000000000..f16657dc0d9f
--- /dev/null
+++ b/Documentation/devicetree/bindings/remoteproc/amd,bram-rproc.yaml
@@ -0,0 +1,98 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/remoteproc/amd,bram-rproc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: AMD BRAM-based Remote Processor
+
+maintainers:
+ - Ben Levinsky <[email protected]>
+
+description: |
+ Soft-core processor subsystem instantiated in AMD programmable logic and
+ using dual-port BRAM for firmware storage and execution.
Isn't the soft-core or FPGA still part of some Xilinx SoC? Or is this
completely different thing from SoC and there is a design WITHOUT SoC
using this remote proc?
In 99% case this is going to be used on Xilinx SOC with programmable logic next
to ARM core.
soft core means - means VHDL/Verilog code synthesized to programmable
logic/fpga. It means exact location in chip varies based on build and
constraints.
hard core - physical HW location - like ARM cores in our chip.
(ARM is providing RTL/code that even ARM cores in fpga emulated platforms are
actually used as soft cores).
Not sure if you want me to talk about that 1% use cases which are also possible
but don't think anybody will design them.
Then I would treat it exactly like every other block of a SoC - you need
a SoC specific compatible. If there is a fallback, SoC specific
compatible should be used in the fallback as well - that's all already
documented in writing-bindings.
But which SOC? We have ZynqMP, Versal, Versal NET, Versal Gen 2. And all of
these will use this configuration.
Do you want to list all of them?
"Then I would treat it exactly like every other block of a SoC"
No issue. Here is snippet.
properties:
compatible:
items:
- enum:
- xlnx,zynqmp-bram-rproc
- xlnx,versal-bram-rproc
- xlnx,versal-net-bram-rproc
- amd,versal2-bram-rproc
- const: amd,bram-rproc
The example should also be updated:
examples:
- |
#include <dt-bindings/gpio/gpio.h>
remoteproc@0 {
compatible = "xlnx,zynqmp-bram-rproc", "amd,bram-rproc";
reg = <0x0 0x40000>;
clocks = <&pl_clk>;
firmware-name = "firmware.elf";
reset-gpios = <&gpio0 0 GPIO_ACTIVE_LOW>;
};
Thanks,
Michal
