[PATCH v7 0/3] Add Efinix FPGA configuration support

[PATCH v7 0/3] Add Efinix FPGA configuration support

[iansdannapel]

From: Ian Dannapel <iansdannapel@gmail.com>

Hi all,

This is v7 of the series adding support for programming Efinix FPGAs
over SPI using the fpga-mgr subsystem.

The series adds DT bindings for the Efinix SPI configuration interface
and a new FPGA manager driver implementing passive SPI configuration.

Testing:
- Verified on a custom board with an Efinix Trion T13 FPGA
- Tested full bitstream configuration over SPI at 25 MHz

Changes since v6:

dt-bindings: fpga: Add Efinix SPI programming bindings
- Require spi-cpha and spi-cpol in the binding to match the driver’s probe-time requirement
- Dropped review tag

fpga-mgr: Add Efinix SPI programming driver
- moved Makefile entry to the end of the FPGA manager section
- moved "keep asserted CS" comment to first appeareance
- removed unnecessary variable struct device *dev = &mgr->dev; in fpga mgr callbacks
- trimmed unused spi_device_id's

Ian Dannapel (3):
  dt-bindings: vendor-prefix: Add prefix for Efinix, Inc.
  dt-bindings: fpga: Add Efinix SPI programming bindings
  fpga-mgr: Add Efinix SPI programming driver

 .../bindings/fpga/efinix,trion-config.yaml    |  98 +++++++
 .../devicetree/bindings/vendor-prefixes.yaml  |   2 +
 drivers/fpga/Kconfig                          |   7 +
 drivers/fpga/Makefile                         |   1 +
 drivers/fpga/efinix-spi.c                     | 260 ++++++++++++++++++
 5 files changed, 368 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/fpga/efinix,trion-config.yaml
 create mode 100644 drivers/fpga/efinix-spi.c

-- 
2.43.0

[PATCH v7 1/3] dt-bindings: vendor-prefix: Add prefix for Efinix, Inc.

[iansdannapel]

From: Ian Dannapel <iansdannapel@gmail.com>

Add entry for Efinix, Inc. (https://www.efinixinc.com/)

Signed-off-by: Ian Dannapel <iansdannapel@gmail.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Alexander Dahl <ada@thorsis.com>
---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index 00bffb9c4469..9e20384ff624 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -485,6 +485,8 @@ patternProperties:
     description: Emtop Embedded Solutions
   "^eeti,.*":
     description: eGalax_eMPIA Technology Inc
+  "^efinix,.*":
+    description: Efinix, Inc.
   "^egnite,.*":
     description: egnite GmbH
   "^einfochips,.*":
-- 
2.43.0

[PATCH v7 2/3] dt-bindings: fpga: Add Efinix SPI programming bindings

[iansdannapel]

From: Ian Dannapel <iansdannapel@gmail.com>

Add device tree bindings documentation for configuring Efinix FPGA
using serial SPI passive programming mode.

Signed-off-by: Ian Dannapel <iansdannapel@gmail.com>
---
 .../bindings/fpga/efinix,trion-config.yaml    | 98 +++++++++++++++++++
 1 file changed, 98 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/fpga/efinix,trion-config.yaml

diff --git a/Documentation/devicetree/bindings/fpga/efinix,trion-config.yaml b/Documentation/devicetree/bindings/fpga/efinix,trion-config.yaml
new file mode 100644
index 000000000000..7c7444ff9c3a
--- /dev/null
+++ b/Documentation/devicetree/bindings/fpga/efinix,trion-config.yaml
@@ -0,0 +1,98 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/fpga/efinix,trion-config.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Efinix SPI FPGA Manager
+
+maintainers:
+  - Ian Dannapel <iansdannapel@gmail.com>
+
+description: |
+  Efinix FPGAs (Trion, Topaz, and Titanium families) support loading bitstreams
+  through "SPI Passive Mode".
+  Additional pin hogs for bus width configuration should be set
+  elsewhere, if necessary.
+
+  References:
+  - https://www.efinixinc.com/docs/an006-configuring-trion-fpgas-v6.3.pdf
+  - https://www.efinixinc.com/docs/an033-configuring-titanium-fpgas-v2.8.pdf
+  - https://www.efinixinc.com/docs/an061-configuring-topaz-fpgas-v1.1.pdf
+
+allOf:
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - enum:
+              - efinix,titanium-config
+              - efinix,topaz-config
+          - const: efinix,trion-config
+      - const: efinix,trion-config
+
+  spi-cpha: true
+
+  spi-cpol: true
+
+  spi-max-frequency:
+    maximum: 25000000
+
+  reg:
+    maxItems: 1
+
+  reset-gpios:
+    description:
+      reset and re-configuration trigger pin (low active)
+    maxItems: 1
+
+  cdone-gpios:
+    description:
+      optional configuration done status pin (high active)
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - reset-gpios
+  - spi-cpha
+  - spi-cpol
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    spi {
+      #address-cells = <1>;
+      #size-cells = <0>;
+      cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
+      fpga-mgr@0 {
+        compatible = "efinix,trion-config";
+        reg = <0>;
+        spi-max-frequency = <25000000>;
+        spi-cpha;
+        spi-cpol;
+        reset-gpios = <&gpio4 17 GPIO_ACTIVE_LOW>;
+        cdone-gpios = <&gpio0 9 GPIO_ACTIVE_HIGH>;
+      };
+    };
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    spi {
+      #address-cells = <1>;
+      #size-cells = <0>;
+      cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
+      fpga-mgr@0 {
+        compatible = "efinix,titanium-config", "efinix,trion-config";
+        reg = <0>;
+        spi-max-frequency = <25000000>;
+        spi-cpha;
+        spi-cpol;
+        reset-gpios = <&gpio4 17 GPIO_ACTIVE_LOW>;
+        cdone-gpios = <&gpio0 9 GPIO_ACTIVE_HIGH>;
+      };
+    };
+...
-- 
2.43.0

[PATCH v7 3/3] fpga-mgr: Add Efinix SPI programming driver

[iansdannapel]

From: Ian Dannapel <iansdannapel@gmail.com>

Add a new driver for loading binary firmware to configuration
RAM using "SPI passive mode" on Efinix FPGAs.

Efinix passive SPI configuration requires chip select to remain asserted
from reset until the complete bitstream and trailing idle clocks have
been transferred, so the driver keeps CS active with cs_change and locks
the SPI bus for the duration of configuration.

Signed-off-by: Ian Dannapel <iansdannapel@gmail.com>
---
 drivers/fpga/Kconfig      |   7 +
 drivers/fpga/Makefile     |   1 +
 drivers/fpga/efinix-spi.c | 260 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 268 insertions(+)
 create mode 100644 drivers/fpga/efinix-spi.c

diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index 37b35f58f0df..748fc210c135 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -288,6 +288,13 @@ config FPGA_MGR_LATTICE_SYSCONFIG_SPI
 	  FPGA manager driver support for Lattice FPGAs programming over slave
 	  SPI sysCONFIG interface.
 
+config FPGA_MGR_EFINIX_SPI
+	tristate "Efinix FPGA configuration over SPI"
+	depends on SPI
+	help
+	  FPGA manager driver support for Efinix FPGAs configuration over SPI
+	  (passive mode only).
+
 source "drivers/fpga/tests/Kconfig"
 
 endif # FPGA
diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index aeb89bb13517..6f5798b27e0d 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_FPGA_MGR_LATTICE_SYSCONFIG)	+= lattice-sysconfig.o
 obj-$(CONFIG_FPGA_MGR_LATTICE_SYSCONFIG_SPI)	+= lattice-sysconfig-spi.o
 obj-$(CONFIG_ALTERA_PR_IP_CORE)		+= altera-pr-ip-core.o
 obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT)	+= altera-pr-ip-core-plat.o
+obj-$(CONFIG_FPGA_MGR_EFINIX_SPI)	+= efinix-spi.o
 
 # FPGA Secure Update Drivers
 obj-$(CONFIG_FPGA_M10_BMC_SEC_UPDATE)	+= intel-m10-bmc-sec-update.o
diff --git a/drivers/fpga/efinix-spi.c b/drivers/fpga/efinix-spi.c
new file mode 100644
index 000000000000..ed9a41232a32
--- /dev/null
+++ b/drivers/fpga/efinix-spi.c
@@ -0,0 +1,260 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * FPGA Manager Driver for Efinix
+ *
+ * Copyright (C) 2025 iris-GmbH infrared & intelligent sensors
+ *
+ * Ian Dannapel <iansdannapel@gmail.com>
+ *
+ * Load Efinix FPGA firmware over SPI using the serial configuration interface.
+ *
+ * Note: Only passive mode (host initiates transfer) is currently supported.
+ */
+
+#include <linux/delay.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/spi/spi.h>
+
+/*
+ * 13 dummy bytes generate 104 SPI clock cycles (8 bits each).
+ * Used to meet the requirement for >100 clock cycles idle sequence.
+ */
+#define EFINIX_SPI_IDLE_CYCLES_BYTES 13
+
+/*
+ * tDMIN: Minimum time between deassertion of CRESET_N to first
+ * valid configuration data. (32 µs)
+ */
+#define EFINIX_TDMIN_US_MIN    35
+#define EFINIX_TDMIN_US_MAX    40
+
+/*
+ * tCRESET_N: Minimum CRESET_N low pulse width required to
+ * trigger re-configuration. (320 ns)
+ */
+#define EFINIX_TCRESETN_DELAY_MIN_US  1
+#define EFINIX_TCRESETN_DELAY_MAX_US  2
+
+/*
+ * tUSER: Minimum configuration duration after CDONE goes high
+ * before entering user mode. (25 µs)
+ */
+#define EFINIX_TUSER_US_MIN    30
+#define EFINIX_TUSER_US_MAX    35
+
+struct efinix_spi_conf {
+	struct spi_device *spi;
+	struct gpio_desc *cdone;
+	struct gpio_desc *reset;
+};
+
+static void efinix_spi_reset(struct efinix_spi_conf *conf)
+{
+	gpiod_set_value(conf->reset, 1);
+	usleep_range(EFINIX_TCRESETN_DELAY_MIN_US, EFINIX_TCRESETN_DELAY_MAX_US);
+	gpiod_set_value(conf->reset, 0);
+	usleep_range(EFINIX_TDMIN_US_MIN, EFINIX_TDMIN_US_MAX);
+}
+
+static enum fpga_mgr_states efinix_spi_state(struct fpga_manager *mgr)
+{
+	struct efinix_spi_conf *conf = mgr->priv;
+
+	if (conf->cdone && gpiod_get_value(conf->cdone) == 1)
+		return FPGA_MGR_STATE_OPERATING;
+
+	return FPGA_MGR_STATE_UNKNOWN;
+}
+
+static int efinix_spi_write_init(struct fpga_manager *mgr,
+				 struct fpga_image_info *info,
+				 const char *buf, size_t count)
+{
+	struct efinix_spi_conf *conf = mgr->priv;
+	struct spi_transfer assert_cs = {
+		/* Keep CS asserted across configuration. */
+		.cs_change = 1,
+	};
+	struct spi_message message;
+	int ret;
+
+	if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
+		dev_err(&mgr->dev, "Partial reconfiguration not supported\n");
+		return -EOPNOTSUPP;
+	}
+
+	/*
+	 * Efinix passive SPI configuration requires chip select to stay
+	 * asserted from reset until the bitstream is fully clocked in.
+	 * Lock the SPI bus so no other device can toggle CS between the
+	 * reset pulse and the write/complete transfers.
+	 */
+	spi_bus_lock(conf->spi->controller);
+	spi_message_init_with_transfers(&message, &assert_cs, 1);
+	ret = spi_sync_locked(conf->spi, &message);
+	if (ret) {
+		spi_bus_unlock(conf->spi->controller);
+		return ret;
+	}
+
+	/* Reset with CS asserted */
+	efinix_spi_reset(conf);
+
+	return 0;
+}
+
+static int efinix_spi_write(struct fpga_manager *mgr, const char *buf,
+			    size_t count)
+{
+	struct spi_transfer write_xfer = {
+		.tx_buf = buf,
+		.len = count,
+		.cs_change = 1,
+	};
+	struct efinix_spi_conf *conf = mgr->priv;
+	struct spi_message message;
+	int ret;
+
+	spi_message_init_with_transfers(&message, &write_xfer, 1);
+	ret = spi_sync_locked(conf->spi, &message);
+	if (ret) {
+		dev_err(&mgr->dev, "SPI error in firmware write: %d\n", ret);
+		spi_bus_unlock(conf->spi->controller);
+	}
+
+	return ret;
+}
+
+static int efinix_spi_write_complete(struct fpga_manager *mgr,
+				     struct fpga_image_info *info)
+{
+	unsigned long timeout =
+		jiffies + usecs_to_jiffies(info->config_complete_timeout_us);
+	struct spi_transfer clk_cycles = {
+		.len = EFINIX_SPI_IDLE_CYCLES_BYTES,
+		/* Release CS after the trailing idle clocks are sent. */
+		.cs_change = 0,
+	};
+	struct efinix_spi_conf *conf = mgr->priv;
+	struct spi_message message;
+	int done, ret;
+	bool expired = false;
+	u8 *dummy_buf;
+
+	dummy_buf = kzalloc(EFINIX_SPI_IDLE_CYCLES_BYTES, GFP_KERNEL);
+	if (!dummy_buf) {
+		ret = -ENOMEM;
+		goto unlock_spi;
+	}
+
+	/*
+	 * Keep the bus locked while sending the trailing idle clocks, then
+	 * let this final transfer deassert CS to terminate configuration.
+	 */
+	clk_cycles.tx_buf = dummy_buf;
+	spi_message_init_with_transfers(&message, &clk_cycles, 1);
+	ret = spi_sync_locked(conf->spi, &message);
+	if (ret) {
+		dev_err(&mgr->dev, "SPI error in write complete: %d\n", ret);
+		goto free_buf;
+	}
+
+	if (conf->cdone) {
+		while (!expired) {
+			done = gpiod_get_value(conf->cdone);
+			if (done < 0) {
+				ret = done;
+				goto free_buf;
+			}
+			if (done)
+				break;
+
+			usleep_range(10, 20);
+			expired = time_after(jiffies, timeout);
+		}
+
+		if (expired) {
+			dev_err(&mgr->dev, "Timeout waiting for CDONE\n");
+			ret = -ETIMEDOUT;
+			goto free_buf;
+		}
+	}
+
+	usleep_range(EFINIX_TUSER_US_MIN, EFINIX_TUSER_US_MAX);
+
+free_buf:
+	kfree(dummy_buf);
+unlock_spi:
+	spi_bus_unlock(conf->spi->controller);
+
+	return ret;
+}
+
+static const struct fpga_manager_ops efinix_spi_ops = {
+	.state = efinix_spi_state,
+	.write_init = efinix_spi_write_init,
+	.write = efinix_spi_write,
+	.write_complete = efinix_spi_write_complete,
+};
+
+static int efinix_spi_probe(struct spi_device *spi)
+{
+	struct efinix_spi_conf *conf;
+	struct fpga_manager *mgr;
+
+	if (!(spi->mode & SPI_CPHA) || !(spi->mode & SPI_CPOL))
+		return dev_err_probe(&spi->dev, -EINVAL,
+				     "Unsupported SPI mode, set CPHA and CPOL\n");
+
+	conf = devm_kzalloc(&spi->dev, sizeof(*conf), GFP_KERNEL);
+	if (!conf)
+		return -ENOMEM;
+
+	conf->reset = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(conf->reset))
+		return dev_err_probe(&spi->dev, PTR_ERR(conf->reset),
+				     "Failed to get RESET gpio\n");
+
+	conf->cdone = devm_gpiod_get_optional(&spi->dev, "cdone", GPIOD_IN);
+	if (IS_ERR(conf->cdone))
+		return dev_err_probe(&spi->dev, PTR_ERR(conf->cdone),
+				     "Failed to get CDONE gpio\n");
+
+	conf->spi = spi;
+
+	mgr = devm_fpga_mgr_register(&spi->dev,
+				     "Efinix FPGA Manager",
+				     &efinix_spi_ops, conf);
+
+	return PTR_ERR_OR_ZERO(mgr);
+}
+
+static const struct of_device_id efinix_spi_of_match[] = {
+	{ .compatible = "efinix,trion-config", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, efinix_spi_of_match);
+
+static const struct spi_device_id efinix_ids[] = {
+	{ "trion-config", 0 },
+	{},
+};
+MODULE_DEVICE_TABLE(spi, efinix_ids);
+
+static struct spi_driver efinix_spi_driver = {
+	.driver = {
+		.name = "efinix-spi",
+		.of_match_table = efinix_spi_of_match,
+	},
+	.probe = efinix_spi_probe,
+	.id_table = efinix_ids,
+};
+
+module_spi_driver(efinix_spi_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Ian Dannapel <iansdannapel@gmail.com>");
+MODULE_DESCRIPTION("Efinix FPGA SPI Programming Driver");
-- 
2.43.0

Re: [PATCH v7 2/3] dt-bindings: fpga: Add Efinix SPI programming bindings

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 379 bytes --]

On Thu, Apr 16, 2026 at 04:42:35PM +0200, iansdannapel@gmail.com wrote:
> From: Ian Dannapel <iansdannapel@gmail.com>
> 
> Add device tree bindings documentation for configuring Efinix FPGA
> using serial SPI passive programming mode.
> 
> Signed-off-by: Ian Dannapel <iansdannapel@gmail.com>

Acked-by: Conor Dooley <conor.dooley@microchip.com>
pw-bot: not-applicable

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