* [PATCH v2 1/2] dt-bindings: remoteproc: document AMD BRAM-based rproc
2026-04-27 16:27 [PATCH v2 0/2] remoteproc: add AMD BRAM-based remote processor driver Ben Levinsky
@ 2026-04-27 16:27 ` Ben Levinsky
2026-04-27 16:27 ` [PATCH v2 2/2] remoteproc: add AMD BRAM-based remote processor driver Ben Levinsky
1 sibling, 0 replies; 3+ messages in thread
From: Ben Levinsky @ 2026-04-27 16:27 UTC (permalink / raw)
To: andersson, mathieu.poirier, robh, krzk+dt, conor+dt,
linux-remoteproc, devicetree, linux-kernel
Cc: michal.simek, tanmay.shah, ben.levinsky
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 <ben.levinsky@amd.com>
---
.../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 <ben.levinsky@amd.com>
+
+description: |
+ Soft-core processor subsystem instantiated in AMD programmable logic and
+ using dual-port BRAM for firmware storage and execution.
+
+ Hardware Architecture:
+
+ Host (PS) Programmable Logic (PL)
+ ========= ======================
+
+ AXI Interface -----------------> AXI BRAM Controller (Host Port)
+ |
+ | Port A
+ v
+ +-----------------+
+ | Dual-Port BRAM |
+ | (shared memory) |
+ +-----------------+
+ ^
+ | Port B
+ |
+ AXI BRAM Controller (Soft-core Port)
+ ^
+ | LMB
+ |
+ Soft-core CPU (MicroBlaze/V)
+
+ GPIO --------------------------> Proc Sys Reset ----> CPU Reset Signal
+
+ Clock -------------------------> Clock Distribution -> CPU Clock
+
+ Memory Architecture:
+
+ The dual-port BRAM allows simultaneous access from both processors:
+ - Port A: Connected to the host AXI BRAM controller for firmware loading
+ - Port B: Connected to the soft-core local memory bus for execution
+
+ The reg property describes the executable BRAM window in the processor-local
+ address space. The parent bus node translates that window to the system
+ physical address space by using standard devicetree address translation
+ through ranges. A clock input and a reset GPIO control the subsystem.
+
+properties:
+ compatible:
+ const: amd,bram-rproc
+
+ reg:
+ maxItems: 1
+ description:
+ Processor-local address and size of the BRAM firmware memory window,
+ as seen by the soft-core processor (typically 0x0 for reset vector).
+ The parent bus ranges property must translate this window to the
+ corresponding system physical address.
+
+ clocks:
+ maxItems: 1
+ description:
+ Clock input for the soft-core processor subsystem.
+
+ firmware-name:
+ maxItems: 1
+ description:
+ Name of the firmware ELF file to load.
+
+ reset-gpios:
+ maxItems: 1
+ description:
+ GPIO specifier controlling the soft-core reset input.
+
+required:
+ - compatible
+ - reg
+ - clocks
+ - reset-gpios
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ remoteproc@0 {
+ compatible = "amd,bram-rproc";
+ reg = <0x0 0x40000>;
+ clocks = <&pl_clk>;
+ firmware-name = "firmware.elf";
+ reset-gpios = <&gpio0 0 GPIO_ACTIVE_LOW>;
+ };
+...
--
2.34.1
^ permalink raw reply related [flat|nested] 3+ messages in thread* [PATCH v2 2/2] remoteproc: add AMD BRAM-based remote processor driver
2026-04-27 16:27 [PATCH v2 0/2] remoteproc: add AMD BRAM-based remote processor driver Ben Levinsky
2026-04-27 16:27 ` [PATCH v2 1/2] dt-bindings: remoteproc: document AMD BRAM-based rproc Ben Levinsky
@ 2026-04-27 16:27 ` Ben Levinsky
1 sibling, 0 replies; 3+ messages in thread
From: Ben Levinsky @ 2026-04-27 16:27 UTC (permalink / raw)
To: andersson, mathieu.poirier, robh, krzk+dt, conor+dt,
linux-remoteproc, devicetree, linux-kernel
Cc: michal.simek, tanmay.shah, ben.levinsky
Add a remoteproc driver for AMD soft-core processor subsystems
instantiated in programmable logic and using dual-port BRAM for
firmware storage and execution.
The driver parses the firmware memory window from the remoteproc device
node's reg property, interprets that address and size in the
processor-local address space, and then uses standard devicetree
address translation through the parent bus ranges property to obtain
the corresponding Linux-visible system physical address.
The resulting translated region is registered as the executable
remoteproc carveout and coredump segment.
The processor is controlled through an active-low reset GPIO and a
subsystem clock. The clock is enabled before reset is released, and the
processor is kept in reset until firmware loading completes.
The firmware-name property is optional, allowing the firmware image to
be assigned later. Firmware images without a resource table are also
accepted.
Signed-off-by: Ben Levinsky <ben.levinsky@amd.com>
---
MAINTAINERS | 7 +
drivers/remoteproc/Kconfig | 14 ++
drivers/remoteproc/Makefile | 1 +
drivers/remoteproc/amd_bram_rproc.c | 243 ++++++++++++++++++++++++++++
4 files changed, 265 insertions(+)
create mode 100644 drivers/remoteproc/amd_bram_rproc.c
diff --git a/MAINTAINERS b/MAINTAINERS
index c871acf2179c..172539971950 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1037,6 +1037,13 @@ S: Maintained
F: Documentation/devicetree/bindings/w1/amd,axi-1wire-host.yaml
F: drivers/w1/masters/amd_axi_w1.c
+AMD BRAM REMOTEPROC DRIVER
+M: Ben Levinsky <ben.levinsky@amd.com>
+L: linux-remoteproc@vger.kernel.org
+S: Maintained
+F: Documentation/devicetree/bindings/remoteproc/amd,bram-rproc.yaml
+F: drivers/remoteproc/amd_bram_rproc.c
+
AMD CDX BUS DRIVER
M: Nipun Gupta <nipun.gupta@amd.com>
M: Nikhil Agarwal <nikhil.agarwal@amd.com>
diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
index ee54436fea5a..9a2a887ede8a 100644
--- a/drivers/remoteproc/Kconfig
+++ b/drivers/remoteproc/Kconfig
@@ -23,6 +23,20 @@ config REMOTEPROC_CDEV
It's safe to say N if you don't want to use this interface.
+config AMD_BRAM_REMOTEPROC
+ tristate "AMD BRAM-based remoteproc support"
+ depends on OF && COMMON_CLK && (GPIOLIB || COMPILE_TEST)
+ help
+ Say y or m here to support a BRAM-based remote processor managed
+ through the remoteproc framework.
+
+ This driver matches designs where executable firmware memory is
+ described in the BRAM-local address space and translated to
+ the system physical address space with standard devicetree address
+ translation.
+
+ If unsure, say N.
+
config IMX_REMOTEPROC
tristate "i.MX remoteproc support"
depends on ARCH_MXC
diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
index 1c7598b8475d..5c39664b50c3 100644
--- a/drivers/remoteproc/Makefile
+++ b/drivers/remoteproc/Makefile
@@ -11,6 +11,7 @@ remoteproc-y += remoteproc_sysfs.o
remoteproc-y += remoteproc_virtio.o
remoteproc-y += remoteproc_elf_loader.o
obj-$(CONFIG_REMOTEPROC_CDEV) += remoteproc_cdev.o
+obj-$(CONFIG_AMD_BRAM_REMOTEPROC) += amd_bram_rproc.o
obj-$(CONFIG_IMX_REMOTEPROC) += imx_rproc.o
obj-$(CONFIG_IMX_DSP_REMOTEPROC) += imx_dsp_rproc.o
obj-$(CONFIG_INGENIC_VPU_RPROC) += ingenic_rproc.o
diff --git a/drivers/remoteproc/amd_bram_rproc.c b/drivers/remoteproc/amd_bram_rproc.c
new file mode 100644
index 000000000000..aa346b80e84c
--- /dev/null
+++ b/drivers/remoteproc/amd_bram_rproc.c
@@ -0,0 +1,243 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD BRAM-based Remote Processor driver
+ *
+ * Copyright (C) 2026 Advanced Micro Devices, Inc.
+ *
+ * This driver supports soft-core processors (MicroBlaze, MicroBlaze-V, or
+ * similar) instantiated in AMD programmable logic, using dual-port BRAM
+ * for firmware storage and execution.
+ *
+ * The firmware memory (BRAM) is described in the processor-local address
+ * space and translated to the Linux-visible system physical address with
+ * standard devicetree address translation.
+ *
+ * Reset is controlled via GPIO connected to Processor System Reset IP.
+ */
+
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/gpio/consumer.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/remoteproc.h>
+
+#include "remoteproc_internal.h"
+
+/**
+ * struct amd_bram_rproc - AMD BRAM-based remoteproc private data
+ * @dev: device pointer
+ * @reset: GPIO descriptor for reset control (active-low)
+ * @clk: processor clock
+ */
+struct amd_bram_rproc {
+ struct device *dev;
+ struct gpio_desc *reset;
+ struct clk *clk;
+};
+
+static int amd_bram_rproc_mem_map(struct rproc *rproc,
+ struct rproc_mem_entry *mem)
+{
+ void __iomem *va;
+
+ va = ioremap_wc(mem->dma, mem->len);
+ if (!va)
+ return -ENOMEM;
+
+ mem->va = (__force void *)va;
+ mem->is_iomem = true;
+
+ return 0;
+}
+
+static int amd_bram_rproc_mem_unmap(struct rproc *rproc,
+ struct rproc_mem_entry *mem)
+{
+ iounmap((void __iomem *)mem->va);
+
+ return 0;
+}
+
+static int amd_bram_rproc_prepare(struct rproc *rproc)
+{
+ struct amd_bram_rproc *priv = rproc->priv;
+ struct rproc_mem_entry *mem;
+ struct resource res;
+ u64 da, size;
+ int ret;
+
+ ret = of_property_read_reg(priv->dev->of_node, 0, &da, &size);
+ if (ret) {
+ dev_err(priv->dev, "failed to parse executable memory reg\n");
+ return ret;
+ }
+
+ if (!size || size > U32_MAX) {
+ dev_err(priv->dev, "invalid executable memory size\n");
+ return -EINVAL;
+ }
+
+ if (da > U32_MAX) {
+ dev_err(priv->dev, "invalid executable memory address\n");
+ return -EINVAL;
+ }
+
+ ret = of_address_to_resource(priv->dev->of_node, 0, &res);
+ if (ret) {
+ dev_err(priv->dev, "failed to translate executable memory reg\n");
+ return ret;
+ }
+
+ mem = rproc_mem_entry_init(priv->dev, NULL, (dma_addr_t)res.start,
+ (size_t)size, da,
+ amd_bram_rproc_mem_map,
+ amd_bram_rproc_mem_unmap,
+ dev_name(priv->dev));
+ if (!mem)
+ return -ENOMEM;
+
+ rproc_add_carveout(rproc, mem);
+ rproc_coredump_add_segment(rproc, da, (size_t)size);
+
+ return 0;
+}
+
+static int amd_bram_rproc_start(struct rproc *rproc)
+{
+ struct amd_bram_rproc *priv = rproc->priv;
+ int ret;
+
+ /* Enable clock before releasing reset */
+ ret = clk_prepare_enable(priv->clk);
+ if (ret) {
+ dev_err(priv->dev, "failed to enable clock: %d\n", ret);
+ return ret;
+ }
+
+ /* Deassert reset and let the processor run. */
+ ret = gpiod_set_value_cansleep(priv->reset, 0);
+ if (ret) {
+ dev_err(priv->dev, "failed to deassert reset: %d\n", ret);
+ clk_disable_unprepare(priv->clk);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int amd_bram_rproc_stop(struct rproc *rproc)
+{
+ struct amd_bram_rproc *priv = rproc->priv;
+ int ret;
+
+ /* Assert reset before disabling the processor clock. */
+ ret = gpiod_set_value_cansleep(priv->reset, 1);
+ if (ret) {
+ dev_err(priv->dev, "failed to assert reset: %d\n", ret);
+ return ret;
+ }
+
+ /* Disable clock after asserting reset */
+ clk_disable_unprepare(priv->clk);
+
+ return 0;
+}
+
+static int amd_bram_rproc_parse_fw(struct rproc *rproc,
+ const struct firmware *fw)
+{
+ int ret;
+
+ ret = rproc_elf_load_rsc_table(rproc, fw);
+ if (ret == -EINVAL) {
+ dev_dbg(&rproc->dev, "no resource table found\n");
+ return 0;
+ }
+
+ return ret;
+}
+
+static const struct rproc_ops amd_bram_rproc_ops = {
+ .prepare = amd_bram_rproc_prepare,
+ .start = amd_bram_rproc_start,
+ .stop = amd_bram_rproc_stop,
+ .load = rproc_elf_load_segments,
+ .sanity_check = rproc_elf_sanity_check,
+ .get_boot_addr = rproc_elf_get_boot_addr,
+ .parse_fw = amd_bram_rproc_parse_fw,
+};
+
+static int amd_bram_rproc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct amd_bram_rproc *priv;
+ const char *fw_name = NULL;
+ struct rproc *rproc;
+ int ret;
+
+ ret = rproc_of_parse_firmware(dev, 0, &fw_name);
+ if (ret < 0 && ret != -EINVAL)
+ return dev_err_probe(dev, ret,
+ "failed to parse firmware-name property\n");
+
+ rproc = devm_rproc_alloc(dev, dev_name(dev), &amd_bram_rproc_ops,
+ fw_name, sizeof(*priv));
+ if (!rproc)
+ return -ENOMEM;
+
+ priv = rproc->priv;
+ priv->dev = dev;
+
+ /* Get the processor clock */
+ priv->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(priv->clk))
+ return dev_err_probe(dev, PTR_ERR(priv->clk),
+ "failed to get clock\n");
+
+ /*
+ * Keep the processor in reset until remoteproc has finished loading
+ * firmware into the executable memory window described by reg and
+ * translated through the parent bus ranges property.
+ */
+ priv->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(priv->reset))
+ return dev_err_probe(dev, PTR_ERR(priv->reset),
+ "failed to get reset gpio\n");
+
+ rproc->auto_boot = false;
+
+ ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to set DMA mask\n");
+
+ platform_set_drvdata(pdev, rproc);
+
+ ret = devm_rproc_add(dev, rproc);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to register rproc\n");
+
+ return 0;
+}
+
+static const struct of_device_id amd_bram_rproc_of_match[] = {
+ { .compatible = "amd,bram-rproc" },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, amd_bram_rproc_of_match);
+
+static struct platform_driver amd_bram_rproc_driver = {
+ .probe = amd_bram_rproc_probe,
+ .driver = {
+ .name = "amd-bram-rproc",
+ .of_match_table = amd_bram_rproc_of_match,
+ },
+};
+module_platform_driver(amd_bram_rproc_driver);
+
+MODULE_DESCRIPTION("AMD BRAM-based Remote Processor driver");
+MODULE_AUTHOR("Ben Levinsky <ben.levinsky@amd.com>");
+MODULE_LICENSE("GPL");
--
2.34.1
^ permalink raw reply related [flat|nested] 3+ messages in thread