[RFC PATCH v4 0/4] fpga: add initial KUnit tests for the subsystem

[RFC PATCH v4 0/4] fpga: add initial KUnit tests for the subsystem

[Marco Pagani]

This patch set introduces initial KUnit test suites for the FPGA subsystem.

Tests can be run using:
[user@localhost linux]$ ./tools/testing/kunit/kunit.py run --kunitconfig=drivers/fpga/tests

v4:
- Fix build error

v3:
- Calling fpga_bridges_put() between reconfigurations
- Functions for registering fake modules allocate and return context structs

v2:
- Restructured code into multiple suites to test components in isolation
- Reduced code duplication using init and exit methods
- Using a get_bridges() method to build the list of bridges just before programming
- Regions and Bridges are organized topologically
- Changed bitstream/bit to images
- Allocate images dynamically
- Renamed fpga-tests to fpga-test
- Simplified Kconfig
- Add license info to the fpga-test module

Marco Pagani (4):
  fpga: add fake FPGA manager
  fpga: add fake FPGA bridge
  fpga: add fake FPGA region
  fpga: add initial KUnit test suites

 drivers/fpga/Kconfig                  |   2 +
 drivers/fpga/Makefile                 |   3 +
 drivers/fpga/tests/.kunitconfig       |   5 +
 drivers/fpga/tests/Kconfig            |  11 +
 drivers/fpga/tests/Makefile           |   6 +
 drivers/fpga/tests/fake-fpga-bridge.c | 242 +++++++++++++
 drivers/fpga/tests/fake-fpga-bridge.h |  36 ++
 drivers/fpga/tests/fake-fpga-mgr.c    | 386 +++++++++++++++++++++
 drivers/fpga/tests/fake-fpga-mgr.h    |  43 +++
 drivers/fpga/tests/fake-fpga-region.c | 259 ++++++++++++++
 drivers/fpga/tests/fake-fpga-region.h |  40 +++
 drivers/fpga/tests/fpga-test.c        | 479 ++++++++++++++++++++++++++
 12 files changed, 1512 insertions(+)
 create mode 100644 drivers/fpga/tests/.kunitconfig
 create mode 100644 drivers/fpga/tests/Kconfig
 create mode 100644 drivers/fpga/tests/Makefile
 create mode 100644 drivers/fpga/tests/fake-fpga-bridge.c
 create mode 100644 drivers/fpga/tests/fake-fpga-bridge.h
 create mode 100644 drivers/fpga/tests/fake-fpga-mgr.c
 create mode 100644 drivers/fpga/tests/fake-fpga-mgr.h
 create mode 100644 drivers/fpga/tests/fake-fpga-region.c
 create mode 100644 drivers/fpga/tests/fake-fpga-region.h
 create mode 100644 drivers/fpga/tests/fpga-test.c


base-commit: 6a8f57ae2eb07ab39a6f0ccad60c760743051026
-- 
2.39.2

[RFC PATCH v4 1/4] fpga: add fake FPGA manager

[Marco Pagani]

Add fake FPGA manager platform driver with support functions.
The driver checks the programming sequence using KUnit expectations.
This module is part of the KUnit tests for the FPGA subsystem.

Signed-off-by: Marco Pagani <marpagan@redhat.com>
---
 drivers/fpga/tests/fake-fpga-mgr.c | 386 +++++++++++++++++++++++++++++
 drivers/fpga/tests/fake-fpga-mgr.h |  43 ++++
 2 files changed, 429 insertions(+)
 create mode 100644 drivers/fpga/tests/fake-fpga-mgr.c
 create mode 100644 drivers/fpga/tests/fake-fpga-mgr.h

diff --git a/drivers/fpga/tests/fake-fpga-mgr.c b/drivers/fpga/tests/fake-fpga-mgr.c
new file mode 100644
index 000000000000..636df637b291
--- /dev/null
+++ b/drivers/fpga/tests/fake-fpga-mgr.c
@@ -0,0 +1,386 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for the fake FPGA manager
+ *
+ * Copyright (C) 2023 Red Hat, Inc.
+ *
+ * Author: Marco Pagani <marpagan@redhat.com>
+ */
+
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <kunit/test.h>
+
+#include "fake-fpga-mgr.h"
+
+#define FAKE_FPGA_MGR_DEV_NAME	"fake_fpga_mgr"
+
+#define FAKE_HEADER_BYTE	0x3f
+#define FAKE_HEADER_SIZE	FPGA_IMG_BLOCK
+
+struct fake_mgr_priv {
+	int rcfg_count;
+	bool op_parse_header;
+	bool op_write_init;
+	bool op_write;
+	bool op_write_sg;
+	bool op_write_complete;
+	struct kunit *test;
+};
+
+struct fake_mgr_data {
+	struct kunit *test;
+};
+
+static void check_header(struct kunit *test, const u8 *buf);
+
+static enum fpga_mgr_states op_state(struct fpga_manager *mgr)
+{
+	struct fake_mgr_priv *priv;
+
+	priv = mgr->priv;
+
+	if (priv->test)
+		kunit_info(priv->test, "Fake FPGA manager: state\n");
+
+	return FPGA_MGR_STATE_UNKNOWN;
+}
+
+static u64 op_status(struct fpga_manager *mgr)
+{
+	struct fake_mgr_priv *priv;
+
+	priv = mgr->priv;
+
+	if (priv->test)
+		kunit_info(priv->test, "Fake FPGA manager: status\n");
+
+	return 0;
+}
+
+static int op_parse_header(struct fpga_manager *mgr, struct fpga_image_info *info,
+			   const char *buf, size_t count)
+{
+	struct fake_mgr_priv *priv;
+
+	priv = mgr->priv;
+
+	if (priv->test) {
+		kunit_info(priv->test, "Fake FPGA manager: parse_header\n");
+
+		KUNIT_EXPECT_EQ(priv->test, mgr->state,
+				FPGA_MGR_STATE_PARSE_HEADER);
+
+		check_header(priv->test, buf);
+	}
+
+	priv->op_parse_header = true;
+
+	return 0;
+}
+
+static int op_write_init(struct fpga_manager *mgr, struct fpga_image_info *info,
+			 const char *buf, size_t count)
+{
+	struct fake_mgr_priv *priv;
+
+	priv = mgr->priv;
+
+	if (priv->test) {
+		kunit_info(priv->test, "Fake FPGA manager: write_init\n");
+
+		KUNIT_EXPECT_EQ(priv->test, mgr->state,
+				FPGA_MGR_STATE_WRITE_INIT);
+	}
+
+	priv->op_write_init = true;
+
+	return 0;
+}
+
+static int op_write(struct fpga_manager *mgr, const char *buf, size_t count)
+{
+	struct fake_mgr_priv *priv;
+
+	priv = mgr->priv;
+
+	if (priv->test) {
+		kunit_info(priv->test, "Fake FPGA manager: write\n");
+
+		KUNIT_EXPECT_EQ(priv->test, mgr->state,
+				FPGA_MGR_STATE_WRITE);
+	}
+
+	priv->op_write = true;
+
+	return 0;
+}
+
+static int op_write_sg(struct fpga_manager *mgr, struct sg_table *sgt)
+{
+	struct fake_mgr_priv *priv;
+
+	priv = mgr->priv;
+
+	if (priv->test) {
+		kunit_info(priv->test, "Fake FPGA manager: write_sg\n");
+
+		KUNIT_EXPECT_EQ(priv->test, mgr->state,
+				FPGA_MGR_STATE_WRITE);
+	}
+
+	priv->op_write_sg = true;
+
+	return 0;
+}
+
+static int op_write_complete(struct fpga_manager *mgr, struct fpga_image_info *info)
+{
+	struct fake_mgr_priv *priv;
+
+	priv = mgr->priv;
+
+	if (priv->test) {
+		kunit_info(priv->test, "Fake FPGA manager: write_complete\n");
+
+		KUNIT_EXPECT_EQ(priv->test, mgr->state,
+				FPGA_MGR_STATE_WRITE_COMPLETE);
+	}
+
+	priv->op_write_complete = true;
+	priv->rcfg_count++;
+
+	return 0;
+}
+
+static void op_fpga_remove(struct fpga_manager *mgr)
+{
+	struct fake_mgr_priv *priv;
+
+	priv = mgr->priv;
+
+	if (priv->test)
+		kunit_info(priv->test, "Fake FPGA manager: remove\n");
+}
+
+static const struct fpga_manager_ops fake_fpga_mgr_ops = {
+	.initial_header_size = FAKE_HEADER_SIZE,
+	.skip_header = false,
+	.state = op_state,
+	.status = op_status,
+	.parse_header = op_parse_header,
+	.write_init = op_write_init,
+	.write = op_write,
+	.write_sg = op_write_sg,
+	.write_complete = op_write_complete,
+	.fpga_remove = op_fpga_remove,
+};
+
+/**
+ * fake_fpga_mgr_register() - register a fake FPGA manager.
+ * @mgr_ctx: fake FPGA manager context data structure.
+ * @test: KUnit test context object.
+ *
+ * Return: pointer to a new fake FPGA manager on success, an ERR_PTR()
+ * encoded error code on failure.
+ */
+struct fake_fpga_mgr *
+fake_fpga_mgr_register(struct kunit *test, struct device *parent)
+{
+	struct fake_fpga_mgr *mgr_ctx;
+	struct fake_mgr_data pdata;
+	int ret;
+
+	mgr_ctx = kzalloc(sizeof(*mgr_ctx), GFP_KERNEL);
+	if (!mgr_ctx) {
+		ret = -ENOMEM;
+		goto err_mem;
+	}
+
+	mgr_ctx->pdev = platform_device_alloc(FAKE_FPGA_MGR_DEV_NAME,
+					      PLATFORM_DEVID_AUTO);
+	if (!mgr_ctx->pdev) {
+		pr_err("Fake FPGA manager device allocation failed\n");
+		ret = -ENOMEM;
+		goto err_mem;
+	}
+
+	pdata.test = test;
+	platform_device_add_data(mgr_ctx->pdev, &pdata, sizeof(pdata));
+
+	mgr_ctx->pdev->dev.parent = parent;
+	ret = platform_device_add(mgr_ctx->pdev);
+	if (ret) {
+		pr_err("Fake FPGA manager device add failed\n");
+		goto err_pdev;
+	}
+
+	mgr_ctx->mgr = platform_get_drvdata(mgr_ctx->pdev);
+
+	if (test)
+		kunit_info(test, "Fake FPGA manager registered\n");
+
+	return mgr_ctx;
+
+err_pdev:
+	platform_device_put(mgr_ctx->pdev);
+	kfree(mgr_ctx);
+err_mem:
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(fake_fpga_mgr_register);
+
+/**
+ * fake_fpga_mgr_unregister() - unregister a fake FPGA manager.
+ * @mgr_ctx: fake FPGA manager context data structure.
+ */
+void fake_fpga_mgr_unregister(struct fake_fpga_mgr *mgr_ctx)
+{
+	struct fake_mgr_priv *priv;
+	struct kunit *test;
+
+	if (!mgr_ctx)
+		return;
+
+	priv = mgr_ctx->mgr->priv;
+	test = priv->test;
+
+	if (mgr_ctx->pdev) {
+		platform_device_unregister(mgr_ctx->pdev);
+		if (test)
+			kunit_info(test, "Fake FPGA manager unregistered\n");
+	}
+
+	kfree(mgr_ctx);
+}
+EXPORT_SYMBOL_GPL(fake_fpga_mgr_unregister);
+
+/**
+ * fake_fpga_mgr_get_rcfg_count() - get the number of reconfigurations.
+ * @mgr_ctx: fake FPGA manager context data structure.
+ *
+ * Return: number of reconfigurations.
+ */
+int fake_fpga_mgr_get_rcfg_count(const struct fake_fpga_mgr *mgr_ctx)
+{
+	struct fake_mgr_priv *priv;
+
+	priv = mgr_ctx->mgr->priv;
+
+	return priv->rcfg_count;
+}
+EXPORT_SYMBOL_GPL(fake_fpga_mgr_get_rcfg_count);
+
+/**
+ * fake_fpga_mgr_fill_header() - fill an image buffer with the test header.
+ * @buf: image buffer.
+ */
+void fake_fpga_mgr_fill_header(u8 *buf)
+{
+	int i;
+
+	for (i = 0; i < FAKE_HEADER_SIZE; i++)
+		buf[i] = FAKE_HEADER_BYTE;
+}
+EXPORT_SYMBOL_GPL(fake_fpga_mgr_fill_header);
+
+static void check_header(struct kunit *test, const u8 *buf)
+{
+	int i;
+
+	for (i = 0; i < FAKE_HEADER_SIZE; i++)
+		KUNIT_EXPECT_EQ(test, buf[i], FAKE_HEADER_BYTE);
+}
+
+static void clear_op_flags(struct fake_mgr_priv *priv)
+{
+	priv->op_parse_header = false;
+	priv->op_write_init = false;
+	priv->op_write = false;
+	priv->op_write_sg = false;
+	priv->op_write_complete = false;
+}
+
+/**
+ * fake_fpga_mgr_check_write_buf() - check if programming using a buffer succeeded.
+ * @mgr_ctx: fake FPGA manager context data structure.
+ */
+void fake_fpga_mgr_check_write_buf(struct fake_fpga_mgr *mgr_ctx)
+{
+	struct fake_mgr_priv *priv;
+
+	priv = mgr_ctx->mgr->priv;
+
+	if (priv->test) {
+		KUNIT_EXPECT_EQ(priv->test, priv->op_parse_header, true);
+		KUNIT_EXPECT_EQ(priv->test, priv->op_write_init, true);
+		KUNIT_EXPECT_EQ(priv->test, priv->op_write, true);
+		KUNIT_EXPECT_EQ(priv->test, priv->op_write_complete, true);
+	}
+
+	clear_op_flags(priv);
+}
+EXPORT_SYMBOL_GPL(fake_fpga_mgr_check_write_buf);
+
+/**
+ * fake_fpga_mgr_check_write_sgt() - check if programming using a s.g. table succeeded.
+ * @mgr_ctx: fake FPGA manager context data structure.
+ */
+void fake_fpga_mgr_check_write_sgt(struct fake_fpga_mgr *mgr_ctx)
+{
+	struct fake_mgr_priv *priv;
+
+	priv = mgr_ctx->mgr->priv;
+
+	if (priv->test) {
+		KUNIT_EXPECT_EQ(priv->test, priv->op_parse_header, true);
+		KUNIT_EXPECT_EQ(priv->test, priv->op_write_init, true);
+		KUNIT_EXPECT_EQ(priv->test, priv->op_write_sg, true);
+		KUNIT_EXPECT_EQ(priv->test, priv->op_write_complete, true);
+	}
+
+	clear_op_flags(priv);
+}
+EXPORT_SYMBOL_GPL(fake_fpga_mgr_check_write_sgt);
+
+static int fake_fpga_mgr_probe(struct platform_device *pdev)
+{
+	struct device *dev;
+	struct fake_mgr_priv *priv;
+	struct fake_mgr_data *pdata;
+	struct fpga_manager *mgr;
+
+	dev = &pdev->dev;
+	pdata = dev_get_platdata(dev);
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	if (pdata)
+		priv->test = pdata->test;
+
+	mgr = devm_fpga_mgr_register(dev, "Fake FPGA Manager",
+				     &fake_fpga_mgr_ops, priv);
+	if (IS_ERR(mgr))
+		return PTR_ERR(mgr);
+
+	platform_set_drvdata(pdev, mgr);
+
+	return 0;
+}
+
+static struct platform_driver fake_fpga_mgr_drv = {
+	.driver = {
+		.name = FAKE_FPGA_MGR_DEV_NAME
+	},
+	.probe = fake_fpga_mgr_probe,
+};
+
+module_platform_driver(fake_fpga_mgr_drv);
+
+MODULE_AUTHOR("Marco Pagani <marpagan@redhat.com>");
+MODULE_DESCRIPTION("Fake FPGA Manager");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/fpga/tests/fake-fpga-mgr.h b/drivers/fpga/tests/fake-fpga-mgr.h
new file mode 100644
index 000000000000..453672b5df72
--- /dev/null
+++ b/drivers/fpga/tests/fake-fpga-mgr.h
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Header file for the fake FPGA manager
+ *
+ * Copyright (C) 2023 Red Hat, Inc.
+ *
+ * Author: Marco Pagani <marpagan@redhat.com>
+ */
+
+#ifndef __FPGA_FAKE_MGR_H
+#define __FPGA_FAKE_MGR_H
+
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/platform_device.h>
+#include <kunit/test.h>
+
+#define FPGA_IMG_BLOCK	1024
+
+/**
+ * struct fake_fpga_mgr - fake FPGA manager context data structure
+ *
+ * @mgr: FPGA manager.
+ * @pdev: platform device of the FPGA manager.
+ */
+struct fake_fpga_mgr {
+	struct fpga_manager *mgr;
+	struct platform_device *pdev;
+};
+
+struct fake_fpga_mgr *
+fake_fpga_mgr_register(struct kunit *test, struct device *parent);
+
+void fake_fpga_mgr_unregister(struct fake_fpga_mgr *mgr_ctx);
+
+int fake_fpga_mgr_get_rcfg_count(const struct fake_fpga_mgr *mgr_ctx);
+
+void fake_fpga_mgr_fill_header(u8 *buf);
+
+void fake_fpga_mgr_check_write_buf(struct fake_fpga_mgr *mgr_ctx);
+
+void fake_fpga_mgr_check_write_sgt(struct fake_fpga_mgr *mgr_ctx);
+
+#endif /* __FPGA_FAKE_MGR_H */
-- 
2.39.2

Re: [RFC PATCH v4 1/4] fpga: add fake FPGA manager

[Xu Yilun]

On 2023-04-17 at 14:23:05 +0200, Marco Pagani wrote:
> Add fake FPGA manager platform driver with support functions.
> The driver checks the programming sequence using KUnit expectations.
> This module is part of the KUnit tests for the FPGA subsystem.
> 
> Signed-off-by: Marco Pagani <marpagan@redhat.com>
> ---
>  drivers/fpga/tests/fake-fpga-mgr.c | 386 +++++++++++++++++++++++++++++
>  drivers/fpga/tests/fake-fpga-mgr.h |  43 ++++
>  2 files changed, 429 insertions(+)
>  create mode 100644 drivers/fpga/tests/fake-fpga-mgr.c
>  create mode 100644 drivers/fpga/tests/fake-fpga-mgr.h
> 
> diff --git a/drivers/fpga/tests/fake-fpga-mgr.c b/drivers/fpga/tests/fake-fpga-mgr.c
> new file mode 100644
> index 000000000000..636df637b291
> --- /dev/null
> +++ b/drivers/fpga/tests/fake-fpga-mgr.c
> @@ -0,0 +1,386 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for the fake FPGA manager
> + *
> + * Copyright (C) 2023 Red Hat, Inc.
> + *
> + * Author: Marco Pagani <marpagan@redhat.com>
> + */
> +
> +#include <linux/types.h>
> +#include <linux/device.h>
> +#include <linux/platform_device.h>
> +#include <linux/fpga/fpga-mgr.h>
> +#include <kunit/test.h>
> +
> +#include "fake-fpga-mgr.h"
> +
> +#define FAKE_FPGA_MGR_DEV_NAME	"fake_fpga_mgr"
> +
> +#define FAKE_HEADER_BYTE	0x3f
> +#define FAKE_HEADER_SIZE	FPGA_IMG_BLOCK
> +
> +struct fake_mgr_priv {
> +	int rcfg_count;
> +	bool op_parse_header;
> +	bool op_write_init;
> +	bool op_write;
> +	bool op_write_sg;
> +	bool op_write_complete;
> +	struct kunit *test;
> +};
> +
> +struct fake_mgr_data {
> +	struct kunit *test;
> +};
> +
> +static void check_header(struct kunit *test, const u8 *buf);
> +
> +static enum fpga_mgr_states op_state(struct fpga_manager *mgr)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	if (priv->test)
> +		kunit_info(priv->test, "Fake FPGA manager: state\n");
> +
> +	return FPGA_MGR_STATE_UNKNOWN;
> +}
> +
> +static u64 op_status(struct fpga_manager *mgr)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	if (priv->test)
> +		kunit_info(priv->test, "Fake FPGA manager: status\n");
> +
> +	return 0;
> +}
> +
> +static int op_parse_header(struct fpga_manager *mgr, struct fpga_image_info *info,
> +			   const char *buf, size_t count)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	if (priv->test) {
> +		kunit_info(priv->test, "Fake FPGA manager: parse_header\n");
> +
> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
> +				FPGA_MGR_STATE_PARSE_HEADER);
> +
> +		check_header(priv->test, buf);
> +	}
> +
> +	priv->op_parse_header = true;
> +
> +	return 0;
> +}
> +
> +static int op_write_init(struct fpga_manager *mgr, struct fpga_image_info *info,
> +			 const char *buf, size_t count)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	if (priv->test) {
> +		kunit_info(priv->test, "Fake FPGA manager: write_init\n");
> +
> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
> +				FPGA_MGR_STATE_WRITE_INIT);
> +	}
> +
> +	priv->op_write_init = true;
> +
> +	return 0;
> +}
> +
> +static int op_write(struct fpga_manager *mgr, const char *buf, size_t count)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	if (priv->test) {
> +		kunit_info(priv->test, "Fake FPGA manager: write\n");
> +
> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
> +				FPGA_MGR_STATE_WRITE);
> +	}
> +
> +	priv->op_write = true;
> +
> +	return 0;
> +}
> +
> +static int op_write_sg(struct fpga_manager *mgr, struct sg_table *sgt)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	if (priv->test) {
> +		kunit_info(priv->test, "Fake FPGA manager: write_sg\n");
> +
> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
> +				FPGA_MGR_STATE_WRITE);
> +	}
> +
> +	priv->op_write_sg = true;
> +
> +	return 0;
> +}
> +
> +static int op_write_complete(struct fpga_manager *mgr, struct fpga_image_info *info)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	if (priv->test) {
> +		kunit_info(priv->test, "Fake FPGA manager: write_complete\n");
> +
> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
> +				FPGA_MGR_STATE_WRITE_COMPLETE);
> +	}
> +
> +	priv->op_write_complete = true;
> +	priv->rcfg_count++;
> +
> +	return 0;
> +}
> +
> +static void op_fpga_remove(struct fpga_manager *mgr)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	if (priv->test)
> +		kunit_info(priv->test, "Fake FPGA manager: remove\n");
> +}
> +
> +static const struct fpga_manager_ops fake_fpga_mgr_ops = {
> +	.initial_header_size = FAKE_HEADER_SIZE,
> +	.skip_header = false,
> +	.state = op_state,
> +	.status = op_status,
> +	.parse_header = op_parse_header,
> +	.write_init = op_write_init,
> +	.write = op_write,
> +	.write_sg = op_write_sg,
> +	.write_complete = op_write_complete,
> +	.fpga_remove = op_fpga_remove,
> +};
> +
> +/**
> + * fake_fpga_mgr_register() - register a fake FPGA manager.
> + * @mgr_ctx: fake FPGA manager context data structure.
> + * @test: KUnit test context object.
> + *
> + * Return: pointer to a new fake FPGA manager on success, an ERR_PTR()
> + * encoded error code on failure.
> + */
> +struct fake_fpga_mgr *
> +fake_fpga_mgr_register(struct kunit *test, struct device *parent)
> +{
> +	struct fake_fpga_mgr *mgr_ctx;
> +	struct fake_mgr_data pdata;
> +	int ret;
> +
> +	mgr_ctx = kzalloc(sizeof(*mgr_ctx), GFP_KERNEL);
> +	if (!mgr_ctx) {
> +		ret = -ENOMEM;
> +		goto err_mem;
> +	}
> +
> +	mgr_ctx->pdev = platform_device_alloc(FAKE_FPGA_MGR_DEV_NAME,
> +					      PLATFORM_DEVID_AUTO);
> +	if (!mgr_ctx->pdev) {
> +		pr_err("Fake FPGA manager device allocation failed\n");
> +		ret = -ENOMEM;
> +		goto err_mem;
> +	}
> +
> +	pdata.test = test;
> +	platform_device_add_data(mgr_ctx->pdev, &pdata, sizeof(pdata));
> +
> +	mgr_ctx->pdev->dev.parent = parent;
> +	ret = platform_device_add(mgr_ctx->pdev);
> +	if (ret) {
> +		pr_err("Fake FPGA manager device add failed\n");
> +		goto err_pdev;
> +	}
> +
> +	mgr_ctx->mgr = platform_get_drvdata(mgr_ctx->pdev);
> +
> +	if (test)
> +		kunit_info(test, "Fake FPGA manager registered\n");
> +
> +	return mgr_ctx;
> +
> +err_pdev:
> +	platform_device_put(mgr_ctx->pdev);
> +	kfree(mgr_ctx);
> +err_mem:
> +	return ERR_PTR(ret);
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_register);
> +
> +/**
> + * fake_fpga_mgr_unregister() - unregister a fake FPGA manager.
> + * @mgr_ctx: fake FPGA manager context data structure.
> + */
> +void fake_fpga_mgr_unregister(struct fake_fpga_mgr *mgr_ctx)
> +{
> +	struct fake_mgr_priv *priv;
> +	struct kunit *test;
> +
> +	if (!mgr_ctx)
> +		return;
> +
> +	priv = mgr_ctx->mgr->priv;
> +	test = priv->test;
> +
> +	if (mgr_ctx->pdev) {
> +		platform_device_unregister(mgr_ctx->pdev);
> +		if (test)
> +			kunit_info(test, "Fake FPGA manager unregistered\n");
> +	}
> +
> +	kfree(mgr_ctx);
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_unregister);
> +
> +/**
> + * fake_fpga_mgr_get_rcfg_count() - get the number of reconfigurations.
> + * @mgr_ctx: fake FPGA manager context data structure.
> + *
> + * Return: number of reconfigurations.
> + */
> +int fake_fpga_mgr_get_rcfg_count(const struct fake_fpga_mgr *mgr_ctx)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr_ctx->mgr->priv;
> +
> +	return priv->rcfg_count;
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_get_rcfg_count);
> +
> +/**
> + * fake_fpga_mgr_fill_header() - fill an image buffer with the test header.
> + * @buf: image buffer.
> + */
> +void fake_fpga_mgr_fill_header(u8 *buf)
> +{
> +	int i;
> +
> +	for (i = 0; i < FAKE_HEADER_SIZE; i++)
> +		buf[i] = FAKE_HEADER_BYTE;
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_fill_header);
> +
> +static void check_header(struct kunit *test, const u8 *buf)
> +{
> +	int i;
> +
> +	for (i = 0; i < FAKE_HEADER_SIZE; i++)
> +		KUNIT_EXPECT_EQ(test, buf[i], FAKE_HEADER_BYTE);
> +}
> +
> +static void clear_op_flags(struct fake_mgr_priv *priv)
> +{
> +	priv->op_parse_header = false;
> +	priv->op_write_init = false;
> +	priv->op_write = false;
> +	priv->op_write_sg = false;
> +	priv->op_write_complete = false;
> +}
> +
> +/**
> + * fake_fpga_mgr_check_write_buf() - check if programming using a buffer succeeded.
> + * @mgr_ctx: fake FPGA manager context data structure.
> + */
> +void fake_fpga_mgr_check_write_buf(struct fake_fpga_mgr *mgr_ctx)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr_ctx->mgr->priv;
> +
> +	if (priv->test) {
> +		KUNIT_EXPECT_EQ(priv->test, priv->op_parse_header, true);
> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_init, true);
> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write, true);
> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_complete, true);
> +	}
> +
> +	clear_op_flags(priv);
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_check_write_buf);
> +
> +/**
> + * fake_fpga_mgr_check_write_sgt() - check if programming using a s.g. table succeeded.
> + * @mgr_ctx: fake FPGA manager context data structure.
> + */
> +void fake_fpga_mgr_check_write_sgt(struct fake_fpga_mgr *mgr_ctx)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr_ctx->mgr->priv;
> +
> +	if (priv->test) {
> +		KUNIT_EXPECT_EQ(priv->test, priv->op_parse_header, true);
> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_init, true);
> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_sg, true);
> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_complete, true);
> +	}
> +
> +	clear_op_flags(priv);
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_check_write_sgt);

I'm wondering, if we could move all these exported functions out of
fake_fpga driver module. And make this driver module serves FPGA
mgr framework only, just like other fpga drivers do.

I assume the main requirement is to check the statistics produced
by the fake fpga driver. Directly accessing mgr->priv outside the
driver could be unwanted.  To solve this, could we create a shared
buffer for the statistics and pass to fake drivers by platform data.

I hope move all the tester's actions in fpga-test.c, so that people
could easily see from code what a user need to do to enable fpga
reprogramming and what are expected in one file. The fake drivers could
be kept as simple, they only move the process forward and produce
statistics.

Thanks,
Yilun

> +
> +static int fake_fpga_mgr_probe(struct platform_device *pdev)
> +{
> +	struct device *dev;
> +	struct fake_mgr_priv *priv;
> +	struct fake_mgr_data *pdata;
> +	struct fpga_manager *mgr;
> +
> +	dev = &pdev->dev;
> +	pdata = dev_get_platdata(dev);
> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	if (pdata)
> +		priv->test = pdata->test;
> +
> +	mgr = devm_fpga_mgr_register(dev, "Fake FPGA Manager",
> +				     &fake_fpga_mgr_ops, priv);
> +	if (IS_ERR(mgr))
> +		return PTR_ERR(mgr);
> +
> +	platform_set_drvdata(pdev, mgr);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver fake_fpga_mgr_drv = {
> +	.driver = {
> +		.name = FAKE_FPGA_MGR_DEV_NAME
> +	},
> +	.probe = fake_fpga_mgr_probe,
> +};
> +
> +module_platform_driver(fake_fpga_mgr_drv);
> +
> +MODULE_AUTHOR("Marco Pagani <marpagan@redhat.com>");
> +MODULE_DESCRIPTION("Fake FPGA Manager");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/fpga/tests/fake-fpga-mgr.h b/drivers/fpga/tests/fake-fpga-mgr.h
> new file mode 100644
> index 000000000000..453672b5df72
> --- /dev/null
> +++ b/drivers/fpga/tests/fake-fpga-mgr.h
> @@ -0,0 +1,43 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Header file for the fake FPGA manager
> + *
> + * Copyright (C) 2023 Red Hat, Inc.
> + *
> + * Author: Marco Pagani <marpagan@redhat.com>
> + */
> +
> +#ifndef __FPGA_FAKE_MGR_H
> +#define __FPGA_FAKE_MGR_H
> +
> +#include <linux/fpga/fpga-mgr.h>
> +#include <linux/platform_device.h>
> +#include <kunit/test.h>
> +
> +#define FPGA_IMG_BLOCK	1024
> +
> +/**
> + * struct fake_fpga_mgr - fake FPGA manager context data structure
> + *
> + * @mgr: FPGA manager.
> + * @pdev: platform device of the FPGA manager.
> + */
> +struct fake_fpga_mgr {
> +	struct fpga_manager *mgr;
> +	struct platform_device *pdev;
> +};
> +
> +struct fake_fpga_mgr *
> +fake_fpga_mgr_register(struct kunit *test, struct device *parent);
> +
> +void fake_fpga_mgr_unregister(struct fake_fpga_mgr *mgr_ctx);
> +
> +int fake_fpga_mgr_get_rcfg_count(const struct fake_fpga_mgr *mgr_ctx);
> +
> +void fake_fpga_mgr_fill_header(u8 *buf);
> +
> +void fake_fpga_mgr_check_write_buf(struct fake_fpga_mgr *mgr_ctx);
> +
> +void fake_fpga_mgr_check_write_sgt(struct fake_fpga_mgr *mgr_ctx);
> +
> +#endif /* __FPGA_FAKE_MGR_H */
> -- 
> 2.39.2
> 

Re: [RFC PATCH v4 1/4] fpga: add fake FPGA manager

[Marco Pagani]

On 2023-04-20 20:31, Xu Yilun wrote:
> On 2023-04-17 at 14:23:05 +0200, Marco Pagani wrote:
>> Add fake FPGA manager platform driver with support functions.
>> The driver checks the programming sequence using KUnit expectations.
>> This module is part of the KUnit tests for the FPGA subsystem.
>>
>> Signed-off-by: Marco Pagani <marpagan@redhat.com>
>> ---
>>  drivers/fpga/tests/fake-fpga-mgr.c | 386 +++++++++++++++++++++++++++++
>>  drivers/fpga/tests/fake-fpga-mgr.h |  43 ++++
>>  2 files changed, 429 insertions(+)
>>  create mode 100644 drivers/fpga/tests/fake-fpga-mgr.c
>>  create mode 100644 drivers/fpga/tests/fake-fpga-mgr.h
>>
>> diff --git a/drivers/fpga/tests/fake-fpga-mgr.c b/drivers/fpga/tests/fake-fpga-mgr.c
>> new file mode 100644
>> index 000000000000..636df637b291
>> --- /dev/null
>> +++ b/drivers/fpga/tests/fake-fpga-mgr.c
>> @@ -0,0 +1,386 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Driver for the fake FPGA manager
>> + *
>> + * Copyright (C) 2023 Red Hat, Inc.
>> + *
>> + * Author: Marco Pagani <marpagan@redhat.com>
>> + */
>> +
>> +#include <linux/types.h>
>> +#include <linux/device.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/fpga/fpga-mgr.h>
>> +#include <kunit/test.h>
>> +
>> +#include "fake-fpga-mgr.h"
>> +
>> +#define FAKE_FPGA_MGR_DEV_NAME	"fake_fpga_mgr"
>> +
>> +#define FAKE_HEADER_BYTE	0x3f
>> +#define FAKE_HEADER_SIZE	FPGA_IMG_BLOCK
>> +
>> +struct fake_mgr_priv {
>> +	int rcfg_count;
>> +	bool op_parse_header;
>> +	bool op_write_init;
>> +	bool op_write;
>> +	bool op_write_sg;
>> +	bool op_write_complete;
>> +	struct kunit *test;
>> +};
>> +
>> +struct fake_mgr_data {
>> +	struct kunit *test;
>> +};
>> +
>> +static void check_header(struct kunit *test, const u8 *buf);
>> +
>> +static enum fpga_mgr_states op_state(struct fpga_manager *mgr)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +
>> +	priv = mgr->priv;
>> +
>> +	if (priv->test)
>> +		kunit_info(priv->test, "Fake FPGA manager: state\n");
>> +
>> +	return FPGA_MGR_STATE_UNKNOWN;
>> +}
>> +
>> +static u64 op_status(struct fpga_manager *mgr)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +
>> +	priv = mgr->priv;
>> +
>> +	if (priv->test)
>> +		kunit_info(priv->test, "Fake FPGA manager: status\n");
>> +
>> +	return 0;
>> +}
>> +
>> +static int op_parse_header(struct fpga_manager *mgr, struct fpga_image_info *info,
>> +			   const char *buf, size_t count)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +
>> +	priv = mgr->priv;
>> +
>> +	if (priv->test) {
>> +		kunit_info(priv->test, "Fake FPGA manager: parse_header\n");
>> +
>> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
>> +				FPGA_MGR_STATE_PARSE_HEADER);
>> +
>> +		check_header(priv->test, buf);
>> +	}
>> +
>> +	priv->op_parse_header = true;
>> +
>> +	return 0;
>> +}
>> +
>> +static int op_write_init(struct fpga_manager *mgr, struct fpga_image_info *info,
>> +			 const char *buf, size_t count)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +
>> +	priv = mgr->priv;
>> +
>> +	if (priv->test) {
>> +		kunit_info(priv->test, "Fake FPGA manager: write_init\n");
>> +
>> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
>> +				FPGA_MGR_STATE_WRITE_INIT);
>> +	}
>> +
>> +	priv->op_write_init = true;
>> +
>> +	return 0;
>> +}
>> +
>> +static int op_write(struct fpga_manager *mgr, const char *buf, size_t count)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +
>> +	priv = mgr->priv;
>> +
>> +	if (priv->test) {
>> +		kunit_info(priv->test, "Fake FPGA manager: write\n");
>> +
>> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
>> +				FPGA_MGR_STATE_WRITE);
>> +	}
>> +
>> +	priv->op_write = true;
>> +
>> +	return 0;
>> +}
>> +
>> +static int op_write_sg(struct fpga_manager *mgr, struct sg_table *sgt)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +
>> +	priv = mgr->priv;
>> +
>> +	if (priv->test) {
>> +		kunit_info(priv->test, "Fake FPGA manager: write_sg\n");
>> +
>> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
>> +				FPGA_MGR_STATE_WRITE);
>> +	}
>> +
>> +	priv->op_write_sg = true;
>> +
>> +	return 0;
>> +}
>> +
>> +static int op_write_complete(struct fpga_manager *mgr, struct fpga_image_info *info)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +
>> +	priv = mgr->priv;
>> +
>> +	if (priv->test) {
>> +		kunit_info(priv->test, "Fake FPGA manager: write_complete\n");
>> +
>> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
>> +				FPGA_MGR_STATE_WRITE_COMPLETE);
>> +	}
>> +
>> +	priv->op_write_complete = true;
>> +	priv->rcfg_count++;
>> +
>> +	return 0;
>> +}
>> +
>> +static void op_fpga_remove(struct fpga_manager *mgr)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +
>> +	priv = mgr->priv;
>> +
>> +	if (priv->test)
>> +		kunit_info(priv->test, "Fake FPGA manager: remove\n");
>> +}
>> +
>> +static const struct fpga_manager_ops fake_fpga_mgr_ops = {
>> +	.initial_header_size = FAKE_HEADER_SIZE,
>> +	.skip_header = false,
>> +	.state = op_state,
>> +	.status = op_status,
>> +	.parse_header = op_parse_header,
>> +	.write_init = op_write_init,
>> +	.write = op_write,
>> +	.write_sg = op_write_sg,
>> +	.write_complete = op_write_complete,
>> +	.fpga_remove = op_fpga_remove,
>> +};
>> +
>> +/**
>> + * fake_fpga_mgr_register() - register a fake FPGA manager.
>> + * @mgr_ctx: fake FPGA manager context data structure.
>> + * @test: KUnit test context object.
>> + *
>> + * Return: pointer to a new fake FPGA manager on success, an ERR_PTR()
>> + * encoded error code on failure.
>> + */
>> +struct fake_fpga_mgr *
>> +fake_fpga_mgr_register(struct kunit *test, struct device *parent)
>> +{
>> +	struct fake_fpga_mgr *mgr_ctx;
>> +	struct fake_mgr_data pdata;
>> +	int ret;
>> +
>> +	mgr_ctx = kzalloc(sizeof(*mgr_ctx), GFP_KERNEL);
>> +	if (!mgr_ctx) {
>> +		ret = -ENOMEM;
>> +		goto err_mem;
>> +	}
>> +
>> +	mgr_ctx->pdev = platform_device_alloc(FAKE_FPGA_MGR_DEV_NAME,
>> +					      PLATFORM_DEVID_AUTO);
>> +	if (!mgr_ctx->pdev) {
>> +		pr_err("Fake FPGA manager device allocation failed\n");
>> +		ret = -ENOMEM;
>> +		goto err_mem;
>> +	}
>> +
>> +	pdata.test = test;
>> +	platform_device_add_data(mgr_ctx->pdev, &pdata, sizeof(pdata));
>> +
>> +	mgr_ctx->pdev->dev.parent = parent;
>> +	ret = platform_device_add(mgr_ctx->pdev);
>> +	if (ret) {
>> +		pr_err("Fake FPGA manager device add failed\n");
>> +		goto err_pdev;
>> +	}
>> +
>> +	mgr_ctx->mgr = platform_get_drvdata(mgr_ctx->pdev);
>> +
>> +	if (test)
>> +		kunit_info(test, "Fake FPGA manager registered\n");
>> +
>> +	return mgr_ctx;
>> +
>> +err_pdev:
>> +	platform_device_put(mgr_ctx->pdev);
>> +	kfree(mgr_ctx);
>> +err_mem:
>> +	return ERR_PTR(ret);
>> +}
>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_register);
>> +
>> +/**
>> + * fake_fpga_mgr_unregister() - unregister a fake FPGA manager.
>> + * @mgr_ctx: fake FPGA manager context data structure.
>> + */
>> +void fake_fpga_mgr_unregister(struct fake_fpga_mgr *mgr_ctx)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +	struct kunit *test;
>> +
>> +	if (!mgr_ctx)
>> +		return;
>> +
>> +	priv = mgr_ctx->mgr->priv;
>> +	test = priv->test;
>> +
>> +	if (mgr_ctx->pdev) {
>> +		platform_device_unregister(mgr_ctx->pdev);
>> +		if (test)
>> +			kunit_info(test, "Fake FPGA manager unregistered\n");
>> +	}
>> +
>> +	kfree(mgr_ctx);
>> +}
>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_unregister);
>> +
>> +/**
>> + * fake_fpga_mgr_get_rcfg_count() - get the number of reconfigurations.
>> + * @mgr_ctx: fake FPGA manager context data structure.
>> + *
>> + * Return: number of reconfigurations.
>> + */
>> +int fake_fpga_mgr_get_rcfg_count(const struct fake_fpga_mgr *mgr_ctx)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +
>> +	priv = mgr_ctx->mgr->priv;
>> +
>> +	return priv->rcfg_count;
>> +}
>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_get_rcfg_count);
>> +
>> +/**
>> + * fake_fpga_mgr_fill_header() - fill an image buffer with the test header.
>> + * @buf: image buffer.
>> + */
>> +void fake_fpga_mgr_fill_header(u8 *buf)
>> +{
>> +	int i;
>> +
>> +	for (i = 0; i < FAKE_HEADER_SIZE; i++)
>> +		buf[i] = FAKE_HEADER_BYTE;
>> +}
>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_fill_header);
>> +
>> +static void check_header(struct kunit *test, const u8 *buf)
>> +{
>> +	int i;
>> +
>> +	for (i = 0; i < FAKE_HEADER_SIZE; i++)
>> +		KUNIT_EXPECT_EQ(test, buf[i], FAKE_HEADER_BYTE);
>> +}
>> +
>> +static void clear_op_flags(struct fake_mgr_priv *priv)
>> +{
>> +	priv->op_parse_header = false;
>> +	priv->op_write_init = false;
>> +	priv->op_write = false;
>> +	priv->op_write_sg = false;
>> +	priv->op_write_complete = false;
>> +}
>> +
>> +/**
>> + * fake_fpga_mgr_check_write_buf() - check if programming using a buffer succeeded.
>> + * @mgr_ctx: fake FPGA manager context data structure.
>> + */
>> +void fake_fpga_mgr_check_write_buf(struct fake_fpga_mgr *mgr_ctx)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +
>> +	priv = mgr_ctx->mgr->priv;
>> +
>> +	if (priv->test) {
>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_parse_header, true);
>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_init, true);
>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write, true);
>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_complete, true);
>> +	}
>> +
>> +	clear_op_flags(priv);
>> +}
>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_check_write_buf);
>> +
>> +/**
>> + * fake_fpga_mgr_check_write_sgt() - check if programming using a s.g. table succeeded.
>> + * @mgr_ctx: fake FPGA manager context data structure.
>> + */
>> +void fake_fpga_mgr_check_write_sgt(struct fake_fpga_mgr *mgr_ctx)
>> +{
>> +	struct fake_mgr_priv *priv;
>> +
>> +	priv = mgr_ctx->mgr->priv;
>> +
>> +	if (priv->test) {
>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_parse_header, true);
>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_init, true);
>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_sg, true);
>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_complete, true);
>> +	}
>> +
>> +	clear_op_flags(priv);
>> +}
>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_check_write_sgt);
> 
> I'm wondering, if we could move all these exported functions out of
> fake_fpga driver module. And make this driver module serves FPGA
> mgr framework only, just like other fpga drivers do.
> 
> I assume the main requirement is to check the statistics produced
> by the fake fpga driver. Directly accessing mgr->priv outside the
> driver could be unwanted.  To solve this, could we create a shared
> buffer for the statistics and pass to fake drivers by platform data.
> 
> I hope move all the tester's actions in fpga-test.c, so that people
> could easily see from code what a user need to do to enable fpga
> reprogramming and what are expected in one file. The fake drivers could
> be kept as simple, they only move the process forward and produce
> statistics.
> 
> Thanks,
> Yilun
>

I agree with you. Initially, I wanted to keep all KUnit test assertions
and expectations contained in fpga-test. However, I could not find a simple
way to test that the FPGA manager performs the correct state transitions
during programming. So I ended up putting KUnit assertions in the methods
of the low-level fake driver as a first solution.

I like your suggestion of using a shared buffer to have a cleaner
implementation. My only concern is that it would make the code more complex.
I will work on this for V5.

Thanks,
Marco


>> +
>> +static int fake_fpga_mgr_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev;
>> +	struct fake_mgr_priv *priv;
>> +	struct fake_mgr_data *pdata;
>> +	struct fpga_manager *mgr;
>> +
>> +	dev = &pdev->dev;
>> +	pdata = dev_get_platdata(dev);
>> +
>> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>> +	if (!priv)
>> +		return -ENOMEM;
>> +
>> +	if (pdata)
>> +		priv->test = pdata->test;
>> +
>> +	mgr = devm_fpga_mgr_register(dev, "Fake FPGA Manager",
>> +				     &fake_fpga_mgr_ops, priv);
>> +	if (IS_ERR(mgr))
>> +		return PTR_ERR(mgr);
>> +
>> +	platform_set_drvdata(pdev, mgr);
>> +
>> +	return 0;
>> +}
>> +
>> +static struct platform_driver fake_fpga_mgr_drv = {
>> +	.driver = {
>> +		.name = FAKE_FPGA_MGR_DEV_NAME
>> +	},
>> +	.probe = fake_fpga_mgr_probe,
>> +};
>> +
>> +module_platform_driver(fake_fpga_mgr_drv);
>> +
>> +MODULE_AUTHOR("Marco Pagani <marpagan@redhat.com>");
>> +MODULE_DESCRIPTION("Fake FPGA Manager");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/drivers/fpga/tests/fake-fpga-mgr.h b/drivers/fpga/tests/fake-fpga-mgr.h
>> new file mode 100644
>> index 000000000000..453672b5df72
>> --- /dev/null
>> +++ b/drivers/fpga/tests/fake-fpga-mgr.h
>> @@ -0,0 +1,43 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Header file for the fake FPGA manager
>> + *
>> + * Copyright (C) 2023 Red Hat, Inc.
>> + *
>> + * Author: Marco Pagani <marpagan@redhat.com>
>> + */
>> +
>> +#ifndef __FPGA_FAKE_MGR_H
>> +#define __FPGA_FAKE_MGR_H
>> +
>> +#include <linux/fpga/fpga-mgr.h>
>> +#include <linux/platform_device.h>
>> +#include <kunit/test.h>
>> +
>> +#define FPGA_IMG_BLOCK	1024
>> +
>> +/**
>> + * struct fake_fpga_mgr - fake FPGA manager context data structure
>> + *
>> + * @mgr: FPGA manager.
>> + * @pdev: platform device of the FPGA manager.
>> + */
>> +struct fake_fpga_mgr {
>> +	struct fpga_manager *mgr;
>> +	struct platform_device *pdev;
>> +};
>> +
>> +struct fake_fpga_mgr *
>> +fake_fpga_mgr_register(struct kunit *test, struct device *parent);
>> +
>> +void fake_fpga_mgr_unregister(struct fake_fpga_mgr *mgr_ctx);
>> +
>> +int fake_fpga_mgr_get_rcfg_count(const struct fake_fpga_mgr *mgr_ctx);
>> +
>> +void fake_fpga_mgr_fill_header(u8 *buf);
>> +
>> +void fake_fpga_mgr_check_write_buf(struct fake_fpga_mgr *mgr_ctx);
>> +
>> +void fake_fpga_mgr_check_write_sgt(struct fake_fpga_mgr *mgr_ctx);
>> +
>> +#endif /* __FPGA_FAKE_MGR_H */
>> -- 
>> 2.39.2
>>
> 

Re: [RFC PATCH v4 1/4] fpga: add fake FPGA manager

[Marco Pagani]

On 2023-04-26 17:44, Marco Pagani wrote:
> 
> 
> On 2023-04-20 20:31, Xu Yilun wrote:
>> On 2023-04-17 at 14:23:05 +0200, Marco Pagani wrote:
>>> Add fake FPGA manager platform driver with support functions.
>>> The driver checks the programming sequence using KUnit expectations.
>>> This module is part of the KUnit tests for the FPGA subsystem.
>>>
>>> Signed-off-by: Marco Pagani <marpagan@redhat.com>
>>> ---
>>>  drivers/fpga/tests/fake-fpga-mgr.c | 386 +++++++++++++++++++++++++++++
>>>  drivers/fpga/tests/fake-fpga-mgr.h |  43 ++++
>>>  2 files changed, 429 insertions(+)
>>>  create mode 100644 drivers/fpga/tests/fake-fpga-mgr.c
>>>  create mode 100644 drivers/fpga/tests/fake-fpga-mgr.h
>>>
>>> diff --git a/drivers/fpga/tests/fake-fpga-mgr.c b/drivers/fpga/tests/fake-fpga-mgr.c
>>> new file mode 100644
>>> index 000000000000..636df637b291
>>> --- /dev/null
>>> +++ b/drivers/fpga/tests/fake-fpga-mgr.c
>>> @@ -0,0 +1,386 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +/*
>>> + * Driver for the fake FPGA manager
>>> + *
>>> + * Copyright (C) 2023 Red Hat, Inc.
>>> + *
>>> + * Author: Marco Pagani <marpagan@redhat.com>
>>> + */
>>> +
>>> +#include <linux/types.h>
>>> +#include <linux/device.h>
>>> +#include <linux/platform_device.h>
>>> +#include <linux/fpga/fpga-mgr.h>
>>> +#include <kunit/test.h>
>>> +
>>> +#include "fake-fpga-mgr.h"
>>> +
>>> +#define FAKE_FPGA_MGR_DEV_NAME	"fake_fpga_mgr"
>>> +
>>> +#define FAKE_HEADER_BYTE	0x3f
>>> +#define FAKE_HEADER_SIZE	FPGA_IMG_BLOCK
>>> +
>>> +struct fake_mgr_priv {
>>> +	int rcfg_count;
>>> +	bool op_parse_header;
>>> +	bool op_write_init;
>>> +	bool op_write;
>>> +	bool op_write_sg;
>>> +	bool op_write_complete;
>>> +	struct kunit *test;
>>> +};
>>> +
>>> +struct fake_mgr_data {
>>> +	struct kunit *test;
>>> +};
>>> +
>>> +static void check_header(struct kunit *test, const u8 *buf);
>>> +
>>> +static enum fpga_mgr_states op_state(struct fpga_manager *mgr)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +
>>> +	priv = mgr->priv;
>>> +
>>> +	if (priv->test)
>>> +		kunit_info(priv->test, "Fake FPGA manager: state\n");
>>> +
>>> +	return FPGA_MGR_STATE_UNKNOWN;
>>> +}
>>> +
>>> +static u64 op_status(struct fpga_manager *mgr)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +
>>> +	priv = mgr->priv;
>>> +
>>> +	if (priv->test)
>>> +		kunit_info(priv->test, "Fake FPGA manager: status\n");
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int op_parse_header(struct fpga_manager *mgr, struct fpga_image_info *info,
>>> +			   const char *buf, size_t count)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +
>>> +	priv = mgr->priv;
>>> +
>>> +	if (priv->test) {
>>> +		kunit_info(priv->test, "Fake FPGA manager: parse_header\n");
>>> +
>>> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
>>> +				FPGA_MGR_STATE_PARSE_HEADER);
>>> +
>>> +		check_header(priv->test, buf);
>>> +	}
>>> +
>>> +	priv->op_parse_header = true;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int op_write_init(struct fpga_manager *mgr, struct fpga_image_info *info,
>>> +			 const char *buf, size_t count)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +
>>> +	priv = mgr->priv;
>>> +
>>> +	if (priv->test) {
>>> +		kunit_info(priv->test, "Fake FPGA manager: write_init\n");
>>> +
>>> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
>>> +				FPGA_MGR_STATE_WRITE_INIT);
>>> +	}
>>> +
>>> +	priv->op_write_init = true;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int op_write(struct fpga_manager *mgr, const char *buf, size_t count)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +
>>> +	priv = mgr->priv;
>>> +
>>> +	if (priv->test) {
>>> +		kunit_info(priv->test, "Fake FPGA manager: write\n");
>>> +
>>> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
>>> +				FPGA_MGR_STATE_WRITE);
>>> +	}
>>> +
>>> +	priv->op_write = true;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int op_write_sg(struct fpga_manager *mgr, struct sg_table *sgt)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +
>>> +	priv = mgr->priv;
>>> +
>>> +	if (priv->test) {
>>> +		kunit_info(priv->test, "Fake FPGA manager: write_sg\n");
>>> +
>>> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
>>> +				FPGA_MGR_STATE_WRITE);
>>> +	}
>>> +
>>> +	priv->op_write_sg = true;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int op_write_complete(struct fpga_manager *mgr, struct fpga_image_info *info)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +
>>> +	priv = mgr->priv;
>>> +
>>> +	if (priv->test) {
>>> +		kunit_info(priv->test, "Fake FPGA manager: write_complete\n");
>>> +
>>> +		KUNIT_EXPECT_EQ(priv->test, mgr->state,
>>> +				FPGA_MGR_STATE_WRITE_COMPLETE);
>>> +	}
>>> +
>>> +	priv->op_write_complete = true;
>>> +	priv->rcfg_count++;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static void op_fpga_remove(struct fpga_manager *mgr)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +
>>> +	priv = mgr->priv;
>>> +
>>> +	if (priv->test)
>>> +		kunit_info(priv->test, "Fake FPGA manager: remove\n");
>>> +}
>>> +
>>> +static const struct fpga_manager_ops fake_fpga_mgr_ops = {
>>> +	.initial_header_size = FAKE_HEADER_SIZE,
>>> +	.skip_header = false,
>>> +	.state = op_state,
>>> +	.status = op_status,
>>> +	.parse_header = op_parse_header,
>>> +	.write_init = op_write_init,
>>> +	.write = op_write,
>>> +	.write_sg = op_write_sg,
>>> +	.write_complete = op_write_complete,
>>> +	.fpga_remove = op_fpga_remove,
>>> +};
>>> +
>>> +/**
>>> + * fake_fpga_mgr_register() - register a fake FPGA manager.
>>> + * @mgr_ctx: fake FPGA manager context data structure.
>>> + * @test: KUnit test context object.
>>> + *
>>> + * Return: pointer to a new fake FPGA manager on success, an ERR_PTR()
>>> + * encoded error code on failure.
>>> + */
>>> +struct fake_fpga_mgr *
>>> +fake_fpga_mgr_register(struct kunit *test, struct device *parent)
>>> +{
>>> +	struct fake_fpga_mgr *mgr_ctx;
>>> +	struct fake_mgr_data pdata;
>>> +	int ret;
>>> +
>>> +	mgr_ctx = kzalloc(sizeof(*mgr_ctx), GFP_KERNEL);
>>> +	if (!mgr_ctx) {
>>> +		ret = -ENOMEM;
>>> +		goto err_mem;
>>> +	}
>>> +
>>> +	mgr_ctx->pdev = platform_device_alloc(FAKE_FPGA_MGR_DEV_NAME,
>>> +					      PLATFORM_DEVID_AUTO);
>>> +	if (!mgr_ctx->pdev) {
>>> +		pr_err("Fake FPGA manager device allocation failed\n");
>>> +		ret = -ENOMEM;
>>> +		goto err_mem;
>>> +	}
>>> +
>>> +	pdata.test = test;
>>> +	platform_device_add_data(mgr_ctx->pdev, &pdata, sizeof(pdata));
>>> +
>>> +	mgr_ctx->pdev->dev.parent = parent;
>>> +	ret = platform_device_add(mgr_ctx->pdev);
>>> +	if (ret) {
>>> +		pr_err("Fake FPGA manager device add failed\n");
>>> +		goto err_pdev;
>>> +	}
>>> +
>>> +	mgr_ctx->mgr = platform_get_drvdata(mgr_ctx->pdev);
>>> +
>>> +	if (test)
>>> +		kunit_info(test, "Fake FPGA manager registered\n");
>>> +
>>> +	return mgr_ctx;
>>> +
>>> +err_pdev:
>>> +	platform_device_put(mgr_ctx->pdev);
>>> +	kfree(mgr_ctx);
>>> +err_mem:
>>> +	return ERR_PTR(ret);
>>> +}
>>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_register);
>>> +
>>> +/**
>>> + * fake_fpga_mgr_unregister() - unregister a fake FPGA manager.
>>> + * @mgr_ctx: fake FPGA manager context data structure.
>>> + */
>>> +void fake_fpga_mgr_unregister(struct fake_fpga_mgr *mgr_ctx)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +	struct kunit *test;
>>> +
>>> +	if (!mgr_ctx)
>>> +		return;
>>> +
>>> +	priv = mgr_ctx->mgr->priv;
>>> +	test = priv->test;
>>> +
>>> +	if (mgr_ctx->pdev) {
>>> +		platform_device_unregister(mgr_ctx->pdev);
>>> +		if (test)
>>> +			kunit_info(test, "Fake FPGA manager unregistered\n");
>>> +	}
>>> +
>>> +	kfree(mgr_ctx);
>>> +}
>>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_unregister);
>>> +
>>> +/**
>>> + * fake_fpga_mgr_get_rcfg_count() - get the number of reconfigurations.
>>> + * @mgr_ctx: fake FPGA manager context data structure.
>>> + *
>>> + * Return: number of reconfigurations.
>>> + */
>>> +int fake_fpga_mgr_get_rcfg_count(const struct fake_fpga_mgr *mgr_ctx)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +
>>> +	priv = mgr_ctx->mgr->priv;
>>> +
>>> +	return priv->rcfg_count;
>>> +}
>>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_get_rcfg_count);
>>> +
>>> +/**
>>> + * fake_fpga_mgr_fill_header() - fill an image buffer with the test header.
>>> + * @buf: image buffer.
>>> + */
>>> +void fake_fpga_mgr_fill_header(u8 *buf)
>>> +{
>>> +	int i;
>>> +
>>> +	for (i = 0; i < FAKE_HEADER_SIZE; i++)
>>> +		buf[i] = FAKE_HEADER_BYTE;
>>> +}
>>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_fill_header);
>>> +
>>> +static void check_header(struct kunit *test, const u8 *buf)
>>> +{
>>> +	int i;
>>> +
>>> +	for (i = 0; i < FAKE_HEADER_SIZE; i++)
>>> +		KUNIT_EXPECT_EQ(test, buf[i], FAKE_HEADER_BYTE);
>>> +}
>>> +
>>> +static void clear_op_flags(struct fake_mgr_priv *priv)
>>> +{
>>> +	priv->op_parse_header = false;
>>> +	priv->op_write_init = false;
>>> +	priv->op_write = false;
>>> +	priv->op_write_sg = false;
>>> +	priv->op_write_complete = false;
>>> +}
>>> +
>>> +/**
>>> + * fake_fpga_mgr_check_write_buf() - check if programming using a buffer succeeded.
>>> + * @mgr_ctx: fake FPGA manager context data structure.
>>> + */
>>> +void fake_fpga_mgr_check_write_buf(struct fake_fpga_mgr *mgr_ctx)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +
>>> +	priv = mgr_ctx->mgr->priv;
>>> +
>>> +	if (priv->test) {
>>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_parse_header, true);
>>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_init, true);
>>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write, true);
>>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_complete, true);
>>> +	}
>>> +
>>> +	clear_op_flags(priv);
>>> +}
>>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_check_write_buf);
>>> +
>>> +/**
>>> + * fake_fpga_mgr_check_write_sgt() - check if programming using a s.g. table succeeded.
>>> + * @mgr_ctx: fake FPGA manager context data structure.
>>> + */
>>> +void fake_fpga_mgr_check_write_sgt(struct fake_fpga_mgr *mgr_ctx)
>>> +{
>>> +	struct fake_mgr_priv *priv;
>>> +
>>> +	priv = mgr_ctx->mgr->priv;
>>> +
>>> +	if (priv->test) {
>>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_parse_header, true);
>>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_init, true);
>>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_sg, true);
>>> +		KUNIT_EXPECT_EQ(priv->test, priv->op_write_complete, true);
>>> +	}
>>> +
>>> +	clear_op_flags(priv);
>>> +}
>>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_check_write_sgt);
>>
>> I'm wondering, if we could move all these exported functions out of
>> fake_fpga driver module. And make this driver module serves FPGA
>> mgr framework only, just like other fpga drivers do.
>>
>> I assume the main requirement is to check the statistics produced
>> by the fake fpga driver. Directly accessing mgr->priv outside the
>> driver could be unwanted.  To solve this, could we create a shared
>> buffer for the statistics and pass to fake drivers by platform data.
>>
>> I hope move all the tester's actions in fpga-test.c, so that people
>> could easily see from code what a user need to do to enable fpga
>> reprogramming and what are expected in one file. The fake drivers could
>> be kept as simple, they only move the process forward and produce
>> statistics.
>>
>> Thanks,
>> Yilun
>>
> 
> I agree with you. Initially, I wanted to keep all KUnit test assertions
> and expectations contained in fpga-test. However, I could not find a simple
> way to test that the FPGA manager performs the correct state transitions
> during programming. So I ended up putting KUnit assertions in the methods
> of the low-level fake driver as a first solution.
> 
> I like your suggestion of using a shared buffer to have a cleaner
> implementation. My only concern is that it would make the code more complex.
> I will work on this for V5.
> 

I experimented with a couple of alternatives to move all tests inside
fpga-test and remove the external functions. Unfortunately, each alternative
comes with its drawbacks.

Using a shared buffer (e.g., kfifo) to implement an events buffer between
fake mgr/bridge and the fpga-test overcomplicates the code (i.e., defining
message structs, enums for the operations, locks, etc.).

Moving fake modules' (mgr, bridge, region) implementations inside fpga-test
makes fpga-test monolithic and harder to understand and maintain.

Accessing modules' private data directly from fpga-test breaks encapsulation.

Overall, it seems to me that using external functions to get the state of fake
modules is the least-worst alternative. What are your thoughts and preferences?

Thanks,
Marco


>>> [...]

Re: [RFC PATCH v4 1/4] fpga: add fake FPGA manager

[Xu Yilun]

On 2023-05-03 at 18:53:02 +0200, Marco Pagani wrote:
> On 2023-04-26 17:44, Marco Pagani wrote:
> > 
> > 
> > On 2023-04-20 20:31, Xu Yilun wrote:
> >> On 2023-04-17 at 14:23:05 +0200, Marco Pagani wrote:
> >>> Add fake FPGA manager platform driver with support functions.
> >>> The driver checks the programming sequence using KUnit expectations.
> >>> This module is part of the KUnit tests for the FPGA subsystem.
> >>>
> >>> Signed-off-by: Marco Pagani <marpagan@redhat.com>

[...]

> >>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_check_write_sgt);
> >>
> >> I'm wondering, if we could move all these exported functions out of
> >> fake_fpga driver module. And make this driver module serves FPGA
> >> mgr framework only, just like other fpga drivers do.
> >>
> >> I assume the main requirement is to check the statistics produced
> >> by the fake fpga driver. Directly accessing mgr->priv outside the
> >> driver could be unwanted.  To solve this, could we create a shared
> >> buffer for the statistics and pass to fake drivers by platform data.
> >>
> >> I hope move all the tester's actions in fpga-test.c, so that people
> >> could easily see from code what a user need to do to enable fpga
> >> reprogramming and what are expected in one file. The fake drivers could
> >> be kept as simple, they only move the process forward and produce
> >> statistics.
> >>
> >> Thanks,
> >> Yilun
> >>
> > 
> > I agree with you. Initially, I wanted to keep all KUnit test assertions
> > and expectations contained in fpga-test. However, I could not find a simple
> > way to test that the FPGA manager performs the correct state transitions
> > during programming. So I ended up putting KUnit assertions in the methods
> > of the low-level fake driver as a first solution.
> > 
> > I like your suggestion of using a shared buffer to have a cleaner
> > implementation. My only concern is that it would make the code more complex.
> > I will work on this for V5.
> > 
> 
> I experimented with a couple of alternatives to move all tests inside
> fpga-test and remove the external functions. Unfortunately, each alternative
> comes with its drawbacks.
> 
> Using a shared buffer (e.g., kfifo) to implement an events buffer between
> fake mgr/bridge and the fpga-test overcomplicates the code (i.e., defining
> message structs, enums for the operations, locks, etc.).

Oh, I actually didn't expect a message based mechanism for statistics
reading, which is overcomplicated for a test.

Maybe just pass a structured data buffer via platform_data, so that both
fpga-test & fake drivers could recognize and access it directly. fpga-test
could directly check the updated statistics after reprograming and assert
them. Is that OK for you?

Thanks,
Yilun

> 
> Moving fake modules' (mgr, bridge, region) implementations inside fpga-test
> makes fpga-test monolithic and harder to understand and maintain.
> 
> Accessing modules' private data directly from fpga-test breaks encapsulation.
> 
> Overall, it seems to me that using external functions to get the state of fake
> modules is the least-worst alternative. What are your thoughts and preferences?
> 
> Thanks,
> Marco
> 
> 
> >>> [...]
> 

Re: [RFC PATCH v4 1/4] fpga: add fake FPGA manager

[Marco Pagani]

On 2023-05-04 14:25, Xu Yilun wrote:
> On 2023-05-03 at 18:53:02 +0200, Marco Pagani wrote:
>> On 2023-04-26 17:44, Marco Pagani wrote:
>>>
>>>
>>> On 2023-04-20 20:31, Xu Yilun wrote:
>>>> On 2023-04-17 at 14:23:05 +0200, Marco Pagani wrote:
>>>>> Add fake FPGA manager platform driver with support functions.
>>>>> The driver checks the programming sequence using KUnit expectations.
>>>>> This module is part of the KUnit tests for the FPGA subsystem.
>>>>>
>>>>> Signed-off-by: Marco Pagani <marpagan@redhat.com>
> 
> [...]
> 
>>>>> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_check_write_sgt);
>>>>
>>>> I'm wondering, if we could move all these exported functions out of
>>>> fake_fpga driver module. And make this driver module serves FPGA
>>>> mgr framework only, just like other fpga drivers do.
>>>>
>>>> I assume the main requirement is to check the statistics produced
>>>> by the fake fpga driver. Directly accessing mgr->priv outside the
>>>> driver could be unwanted.  To solve this, could we create a shared
>>>> buffer for the statistics and pass to fake drivers by platform data.
>>>>
>>>> I hope move all the tester's actions in fpga-test.c, so that people
>>>> could easily see from code what a user need to do to enable fpga
>>>> reprogramming and what are expected in one file. The fake drivers could
>>>> be kept as simple, they only move the process forward and produce
>>>> statistics.
>>>>
>>>> Thanks,
>>>> Yilun
>>>>
>>>
>>> I agree with you. Initially, I wanted to keep all KUnit test assertions
>>> and expectations contained in fpga-test. However, I could not find a simple
>>> way to test that the FPGA manager performs the correct state transitions
>>> during programming. So I ended up putting KUnit assertions in the methods
>>> of the low-level fake driver as a first solution.
>>>
>>> I like your suggestion of using a shared buffer to have a cleaner
>>> implementation. My only concern is that it would make the code more complex.
>>> I will work on this for V5.
>>>
>>
>> I experimented with a couple of alternatives to move all tests inside
>> fpga-test and remove the external functions. Unfortunately, each alternative
>> comes with its drawbacks.
>>
>> Using a shared buffer (e.g., kfifo) to implement an events buffer between
>> fake mgr/bridge and the fpga-test overcomplicates the code (i.e., defining
>> message structs, enums for the operations, locks, etc.).
> 
> Oh, I actually didn't expect a message based mechanism for statistics
> reading, which is overcomplicated for a test.
> 
> Maybe just pass a structured data buffer via platform_data, so that both
> fpga-test & fake drivers could recognize and access it directly. fpga-test
> could directly check the updated statistics after reprograming and assert
> them. Is that OK for you?
> 
> Thanks,
> Yilun

In principle, yes. I was just concerned that testing all properties with a plain
buffer wouldn't be feasible. With the current implementation, fake-fpga-mgr
tests two distinct sets of properties: (i) all required ops are called during
programming, and (ii) the fpga mgr is in the correct state when each op is called.

I was convinced that testing (ii) would have required some sort of events queue
to trace the calls. However, on second thought, I might simply use fpga_mgr_states
enums to test (ii) using a plain buffer. Moreover, by adding sequence numbers, we
could also test an additional property (iii) ops are called in the right order.
I'll follow the shared buffer approach for V5.

Thanks,
Marco

> 
>>
>> Moving fake modules' (mgr, bridge, region) implementations inside fpga-test
>> makes fpga-test monolithic and harder to understand and maintain.
>>
>> Accessing modules' private data directly from fpga-test breaks encapsulation.
>>
>> Overall, it seems to me that using external functions to get the state of fake
>> modules is the least-worst alternative. What are your thoughts and preferences?
>>
>> Thanks,
>> Marco
>>
>>
>>>>> [...]
>>
> 

[RFC PATCH v4 2/4] fpga: add fake FPGA bridge

[Marco Pagani]

Add fake FPGA bridge driver with support functions. The driver includes
a counter for the number of switching cycles. This module is part of
the KUnit tests for the FPGA subsystem.

Signed-off-by: Marco Pagani <marpagan@redhat.com>
---
 drivers/fpga/tests/fake-fpga-bridge.c | 242 ++++++++++++++++++++++++++
 drivers/fpga/tests/fake-fpga-bridge.h |  36 ++++
 2 files changed, 278 insertions(+)
 create mode 100644 drivers/fpga/tests/fake-fpga-bridge.c
 create mode 100644 drivers/fpga/tests/fake-fpga-bridge.h

diff --git a/drivers/fpga/tests/fake-fpga-bridge.c b/drivers/fpga/tests/fake-fpga-bridge.c
new file mode 100644
index 000000000000..6a62c04a75c0
--- /dev/null
+++ b/drivers/fpga/tests/fake-fpga-bridge.c
@@ -0,0 +1,242 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for the fake FPGA bridge
+ *
+ * Copyright (C) 2023 Red Hat, Inc.
+ *
+ * Author: Marco Pagani <marpagan@redhat.com>
+ */
+
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/fpga/fpga-bridge.h>
+#include <kunit/test.h>
+
+#include "fake-fpga-bridge.h"
+
+#define FAKE_FPGA_BRIDGE_DEV_NAME	"fake_fpga_bridge"
+
+struct fake_bridge_priv {
+	int id;
+	bool enable;
+	int cycles_count;
+	struct kunit *test;
+};
+
+struct fake_bridge_data {
+	struct kunit *test;
+};
+
+static int op_enable_show(struct fpga_bridge *bridge)
+{
+	struct fake_bridge_priv *priv;
+
+	priv = bridge->priv;
+
+	if (priv->test)
+		kunit_info(priv->test, "Fake FPGA bridge %d: enable_show\n",
+			   priv->id);
+
+	return priv->enable;
+}
+
+static int op_enable_set(struct fpga_bridge *bridge, bool enable)
+{
+	struct fake_bridge_priv *priv;
+
+	priv = bridge->priv;
+
+	if (enable && !priv->enable)
+		priv->cycles_count++;
+
+	priv->enable = enable;
+
+	if (priv->test)
+		kunit_info(priv->test, "Fake FPGA bridge %d: enable_set: %d\n",
+			   priv->id, enable);
+
+	return 0;
+}
+
+static void op_remove(struct fpga_bridge *bridge)
+{
+	struct fake_bridge_priv *priv;
+
+	priv = bridge->priv;
+
+	if (priv->test)
+		kunit_info(priv->test, "Fake FPGA bridge: remove\n");
+}
+
+static const struct fpga_bridge_ops fake_fpga_bridge_ops = {
+	.enable_show = op_enable_show,
+	.enable_set = op_enable_set,
+	.fpga_bridge_remove = op_remove,
+};
+
+/**
+ * fake_fpga_bridge_register() - register a fake FPGA bridge.
+ * @parent: parent device.
+ * @test: KUnit test context object.
+ *
+ * Return: pointer to a new fake FPGA bridge on success, an ERR_PTR()
+ * encoded error code on failure.
+ */
+struct fake_fpga_bridge *
+fake_fpga_bridge_register(struct device *parent, struct kunit *test)
+{
+	struct fake_fpga_bridge *bridge_ctx;
+	struct fake_bridge_data pdata;
+	struct fake_bridge_priv *priv;
+	int ret;
+
+	bridge_ctx = kzalloc(sizeof(*bridge_ctx), GFP_KERNEL);
+	if (!bridge_ctx) {
+		ret = -ENOMEM;
+		goto err_mem;
+	}
+
+	bridge_ctx->pdev = platform_device_alloc(FAKE_FPGA_BRIDGE_DEV_NAME,
+						 PLATFORM_DEVID_AUTO);
+	if (!bridge_ctx->pdev) {
+		pr_err("Fake FPGA bridge device allocation failed\n");
+		ret = -ENOMEM;
+		goto err_mem;
+	}
+
+	pdata.test = test;
+	platform_device_add_data(bridge_ctx->pdev, &pdata, sizeof(pdata));
+
+	bridge_ctx->pdev->dev.parent = parent;
+	ret = platform_device_add(bridge_ctx->pdev);
+	if (ret) {
+		pr_err("Fake FPGA bridge device add failed\n");
+		goto err_pdev;
+	}
+
+	bridge_ctx->bridge = platform_get_drvdata(bridge_ctx->pdev);
+
+	if (test) {
+		priv = bridge_ctx->bridge->priv;
+		kunit_info(test, "Fake FPGA bridge %d registered\n", priv->id);
+	}
+
+	return bridge_ctx;
+
+err_pdev:
+	platform_device_put(bridge_ctx->pdev);
+	kfree(bridge_ctx);
+err_mem:
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(fake_fpga_bridge_register);
+
+/**
+ * fake_fpga_bridge_unregister() - unregister a fake FPGA bridge.
+ * @bridge_ctx: fake FPGA bridge context data structure.
+ */
+void fake_fpga_bridge_unregister(struct fake_fpga_bridge *bridge_ctx)
+{
+	struct fake_bridge_priv *priv;
+	struct kunit *test;
+	int id;
+
+	if (!bridge_ctx)
+		return;
+
+	priv = bridge_ctx->bridge->priv;
+	test = priv->test;
+	id = priv->id;
+
+	if (bridge_ctx->pdev) {
+		platform_device_unregister(bridge_ctx->pdev);
+		if (test)
+			kunit_info(test, "Fake FPGA bridge %d unregistered\n", id);
+	}
+
+	kfree(bridge_ctx);
+}
+EXPORT_SYMBOL_GPL(fake_fpga_bridge_unregister);
+
+/**
+ * fake_fpga_bridge_get_state() - get state of a fake FPGA bridge.
+ * @bridge_ctx: fake FPGA bridge context data structure.
+ *
+ * Return: 1 if the bridge is enabled, 0 if disabled.
+ */
+int fake_fpga_bridge_get_state(const struct fake_fpga_bridge *bridge_ctx)
+{
+	return bridge_ctx->bridge->br_ops->enable_show(bridge_ctx->bridge);
+}
+EXPORT_SYMBOL_GPL(fake_fpga_bridge_get_state);
+
+/**
+ * fake_fpga_bridge_get_cycles_count() - get the number of switching cycles.
+ * @bridge_ctx: fake FPGA bridge context data structure.
+ *
+ * Return: number of switching cycles.
+ */
+int fake_fpga_bridge_get_cycles_count(const struct fake_fpga_bridge *bridge_ctx)
+{
+	struct fake_bridge_priv *priv;
+
+	priv = bridge_ctx->bridge->priv;
+
+	return priv->cycles_count;
+}
+EXPORT_SYMBOL_GPL(fake_fpga_bridge_get_cycles_count);
+
+static int fake_fpga_bridge_probe(struct platform_device *pdev)
+{
+	struct device *dev;
+	struct fpga_bridge *bridge;
+	struct fake_bridge_data *pdata;
+	struct fake_bridge_priv *priv;
+	static int id_count;
+
+	dev = &pdev->dev;
+	pdata = dev_get_platdata(dev);
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->id = id_count++;
+	priv->enable = true;
+
+	if (pdata)
+		priv->test = pdata->test;
+
+	bridge = fpga_bridge_register(dev, "Fake FPGA Bridge",
+				      &fake_fpga_bridge_ops, priv);
+	if (IS_ERR(bridge))
+		return PTR_ERR(bridge);
+
+	platform_set_drvdata(pdev, bridge);
+
+	return 0;
+}
+
+static int fake_fpga_bridge_remove(struct platform_device *pdev)
+{
+	struct fpga_bridge *bridge = platform_get_drvdata(pdev);
+
+	fpga_bridge_unregister(bridge);
+
+	return 0;
+}
+
+static struct platform_driver fake_fpga_bridge_drv = {
+	.driver = {
+		.name = FAKE_FPGA_BRIDGE_DEV_NAME
+	},
+	.probe = fake_fpga_bridge_probe,
+	.remove = fake_fpga_bridge_remove,
+};
+
+module_platform_driver(fake_fpga_bridge_drv);
+
+MODULE_AUTHOR("Marco Pagani <marpagan@redhat.com>");
+MODULE_DESCRIPTION("Fake FPGA Bridge");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/fpga/tests/fake-fpga-bridge.h b/drivers/fpga/tests/fake-fpga-bridge.h
new file mode 100644
index 000000000000..a5acfdf18056
--- /dev/null
+++ b/drivers/fpga/tests/fake-fpga-bridge.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Header file for the fake FPGA bridge
+ *
+ * Copyright (C) 2023 Red Hat, Inc.
+ *
+ * Author: Marco Pagani <marpagan@redhat.com>
+ */
+
+#ifndef __FPGA_FAKE_BRIDGE_H
+#define __FPGA_FAKE_BRIDGE_H
+
+#include <linux/platform_device.h>
+#include <kunit/test.h>
+
+/**
+ * struct fake_fpga_bridge - fake FPGA bridge context data structure
+ *
+ * @bridge: FPGA bridge.
+ * @pdev: platform device of the FPGA bridge.
+ */
+struct fake_fpga_bridge {
+	struct fpga_bridge *bridge;
+	struct platform_device *pdev;
+};
+
+struct fake_fpga_bridge *
+fake_fpga_bridge_register(struct device *parent, struct kunit *test);
+
+void fake_fpga_bridge_unregister(struct fake_fpga_bridge *bridge_ctx);
+
+int fake_fpga_bridge_get_state(const struct fake_fpga_bridge *bridge_ctx);
+
+int fake_fpga_bridge_get_cycles_count(const struct fake_fpga_bridge *bridge_ctx);
+
+#endif /* __FPGA_FAKE_BRIDGE_H */
-- 
2.39.2

[RFC PATCH v4 3/4] fpga: add fake FPGA region

[Marco Pagani]

Add fake FPGA region platform driver with support functions. This
module is part of the KUnit tests for the FPGA subsystem.

Signed-off-by: Marco Pagani <marpagan@redhat.com>
---
 drivers/fpga/tests/fake-fpga-region.c | 259 ++++++++++++++++++++++++++
 drivers/fpga/tests/fake-fpga-region.h |  40 ++++
 2 files changed, 299 insertions(+)
 create mode 100644 drivers/fpga/tests/fake-fpga-region.c
 create mode 100644 drivers/fpga/tests/fake-fpga-region.h

diff --git a/drivers/fpga/tests/fake-fpga-region.c b/drivers/fpga/tests/fake-fpga-region.c
new file mode 100644
index 000000000000..b23ae5e94fe6
--- /dev/null
+++ b/drivers/fpga/tests/fake-fpga-region.c
@@ -0,0 +1,259 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for the fake FPGA region
+ *
+ * Copyright (C) 2023 Red Hat, Inc.
+ *
+ * Author: Marco Pagani <marpagan@redhat.com>
+ */
+
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/platform_device.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/fpga/fpga-region.h>
+#include <linux/fpga/fpga-bridge.h>
+#include <kunit/test.h>
+
+#include "fake-fpga-region.h"
+
+#define FAKE_FPGA_REGION_DEV_NAME	"fake_fpga_region"
+
+struct fake_region_priv {
+	int id;
+	struct kunit *test;
+	struct list_head bridge_list;
+};
+
+struct bridge_elem {
+	struct fpga_bridge *bridge;
+	struct list_head node;
+};
+
+struct fake_region_data {
+	struct fpga_manager *mgr;
+	struct kunit *test;
+};
+
+/**
+ * fake_fpga_region_register() - register a fake FPGA region.
+ * @mgr: associated FPGA manager.
+ * @parent: parent device.
+ * @test: KUnit test context object.
+ *
+ * Return: pointer to a new fake FPGA region on success, an ERR_PTR() encoded
+ * error code on failure.
+ */
+struct fake_fpga_region *
+fake_fpga_region_register(struct fpga_manager *mgr, struct device *parent,
+			  struct kunit *test)
+{
+	struct fake_fpga_region *region_ctx;
+	struct fake_region_data pdata;
+	struct fake_region_priv *priv;
+	int ret;
+
+	region_ctx = kzalloc(sizeof(*region_ctx), GFP_KERNEL);
+	if (!region_ctx) {
+		ret = -ENOMEM;
+		goto err_mem;
+	}
+
+	region_ctx->pdev = platform_device_alloc(FAKE_FPGA_REGION_DEV_NAME,
+						 PLATFORM_DEVID_AUTO);
+	if (!region_ctx->pdev) {
+		pr_err("Fake FPGA region device allocation failed\n");
+		ret = -ENOMEM;
+		goto err_mem;
+	}
+
+	pdata.mgr = mgr;
+	pdata.test = test;
+	platform_device_add_data(region_ctx->pdev, &pdata, sizeof(pdata));
+
+	region_ctx->pdev->dev.parent = parent;
+	ret = platform_device_add(region_ctx->pdev);
+	if (ret) {
+		pr_err("Fake FPGA region device add failed\n");
+		goto err_pdev;
+	}
+
+	region_ctx->region = platform_get_drvdata(region_ctx->pdev);
+
+	if (test) {
+		priv = region_ctx->region->priv;
+		kunit_info(test, "Fake FPGA region %d registered\n", priv->id);
+	}
+
+	return region_ctx;
+
+err_pdev:
+	platform_device_put(region_ctx->pdev);
+	kfree(region_ctx);
+err_mem:
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(fake_fpga_region_register);
+
+/**
+ * fake_fpga_region_unregister() - unregister a fake FPGA region.
+ * @region_ctx: fake FPGA region context data structure.
+ */
+void fake_fpga_region_unregister(struct fake_fpga_region *region_ctx)
+{
+	struct fake_region_priv *priv;
+	struct kunit *test;
+	int id;
+
+	if (!region_ctx)
+		return;
+
+	priv = region_ctx->region->priv;
+	test = priv->test;
+	id = priv->id;
+
+	if (region_ctx->pdev) {
+		platform_device_unregister(region_ctx->pdev);
+		if (test)
+			kunit_info(test, "Fake FPGA region %d unregistered\n", id);
+	}
+
+	kfree(region_ctx);
+}
+EXPORT_SYMBOL_GPL(fake_fpga_region_unregister);
+
+/**
+ * fake_fpga_region_add_bridge() - add a bridge to a fake FPGA region.
+ * @region_ctx: fake FPGA region context data structure.
+ * @bridge: FPGA bridge.
+ *
+ * Return: 0 if registration succeeded, an error code otherwise.
+ */
+int fake_fpga_region_add_bridge(struct fake_fpga_region *region_ctx,
+				struct fpga_bridge *bridge)
+{
+	struct fake_region_priv *priv;
+	struct bridge_elem *elem;
+
+	priv = region_ctx->region->priv;
+
+	elem = devm_kzalloc(&region_ctx->pdev->dev, sizeof(*elem), GFP_KERNEL);
+	if (!elem)
+		return -ENOMEM;
+
+	/* Add bridge to the list of bridges in the private context */
+	elem->bridge = bridge;
+	list_add(&elem->node, &priv->bridge_list);
+
+	if (priv->test)
+		kunit_info(priv->test, "Bridge added to fake FPGA region %d\n",
+			   priv->id);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fake_fpga_region_add_bridge);
+
+int fake_fpga_region_program(struct fake_fpga_region *region_ctx)
+{
+	int ret;
+
+	ret = fpga_region_program_fpga(region_ctx->region);
+
+	/* fpga_region_program_fpga() already puts the bridges in case of errors */
+	if (!ret)
+		fpga_bridges_put(&region_ctx->region->bridge_list);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(fake_fpga_region_program);
+
+static int fake_region_get_bridges(struct fpga_region *region)
+{
+	struct fake_region_priv *priv;
+	struct bridge_elem *elem;
+	int ret;
+
+	priv = region->priv;
+
+	/* Copy the list of bridges from the private context to the region */
+	list_for_each_entry(elem, &priv->bridge_list, node) {
+		ret = fpga_bridge_get_to_list(elem->bridge->dev.parent,
+					      region->info,
+					      &region->bridge_list);
+		if (ret)
+			break;
+	}
+
+	return ret;
+}
+
+static int fake_fpga_region_probe(struct platform_device *pdev)
+{
+	struct device *dev;
+	struct fpga_region *region;
+	struct fpga_manager *mgr;
+	struct fake_region_data *pdata;
+	struct fake_region_priv *priv;
+	struct fpga_region_info info;
+	static int id_count;
+
+	dev = &pdev->dev;
+	pdata = dev_get_platdata(dev);
+
+	if (!pdata) {
+		dev_err(&pdev->dev, "Missing platform data\n");
+		return -EINVAL;
+	}
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	mgr = fpga_mgr_get(pdata->mgr->dev.parent);
+	if (IS_ERR(mgr))
+		return PTR_ERR(mgr);
+
+	INIT_LIST_HEAD(&priv->bridge_list);
+	priv->id = id_count++;
+	priv->test = pdata->test;
+
+	memset(&info, 0, sizeof(info));
+	info.priv = priv;
+	info.mgr = mgr;
+	info.get_bridges = fake_region_get_bridges;
+
+	region = fpga_region_register_full(dev, &info);
+	if (IS_ERR(region)) {
+		fpga_mgr_put(mgr);
+		return PTR_ERR(region);
+	}
+
+	platform_set_drvdata(pdev, region);
+
+	return 0;
+}
+
+static int fake_fpga_region_remove(struct platform_device *pdev)
+{
+	struct fpga_region *region = platform_get_drvdata(pdev);
+	struct fpga_manager *mgr = region->mgr;
+
+	fpga_mgr_put(mgr);
+	fpga_region_unregister(region);
+
+	return 0;
+}
+
+static struct platform_driver fake_fpga_region_drv = {
+	.driver = {
+		.name = FAKE_FPGA_REGION_DEV_NAME
+	},
+	.probe = fake_fpga_region_probe,
+	.remove = fake_fpga_region_remove,
+};
+
+module_platform_driver(fake_fpga_region_drv);
+
+MODULE_AUTHOR("Marco Pagani <marpagan@redhat.com>");
+MODULE_DESCRIPTION("Fake FPGA Bridge");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/fpga/tests/fake-fpga-region.h b/drivers/fpga/tests/fake-fpga-region.h
new file mode 100644
index 000000000000..976982c192bc
--- /dev/null
+++ b/drivers/fpga/tests/fake-fpga-region.h
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Header file for the fake FPGA region
+ *
+ * Copyright (C) 2023 Red Hat, Inc.
+ *
+ * Author: Marco Pagani <marpagan@redhat.com>
+ */
+
+#ifndef __FPGA_FAKE_RGN_H
+#define __FPGA_FAKE_RGN_H
+
+#include <linux/platform_device.h>
+#include <kunit/test.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/fpga/fpga-bridge.h>
+
+/**
+ * struct fake_fpga_region - fake FPGA region context data structure
+ *
+ * @region: FPGA region.
+ * @pdev: platform device of the FPGA region.
+ */
+struct fake_fpga_region {
+	struct fpga_region *region;
+	struct platform_device *pdev;
+};
+
+struct fake_fpga_region *
+fake_fpga_region_register(struct fpga_manager *mgr, struct device *parent,
+			  struct kunit *test);
+
+int fake_fpga_region_add_bridge(struct fake_fpga_region *region_ctx,
+				struct fpga_bridge *bridge);
+
+int fake_fpga_region_program(struct fake_fpga_region *region_ctx);
+
+void fake_fpga_region_unregister(struct fake_fpga_region *region_ctx);
+
+#endif /* __FPGA_FAKE_RGN_H */
-- 
2.39.2

Re: [RFC PATCH v4 3/4] fpga: add fake FPGA region

[Xu Yilun]

On 2023-04-17 at 14:23:07 +0200, Marco Pagani wrote:
> Add fake FPGA region platform driver with support functions. This
> module is part of the KUnit tests for the FPGA subsystem.
> 
> Signed-off-by: Marco Pagani <marpagan@redhat.com>
> ---
>  drivers/fpga/tests/fake-fpga-region.c | 259 ++++++++++++++++++++++++++
>  drivers/fpga/tests/fake-fpga-region.h |  40 ++++
>  2 files changed, 299 insertions(+)
>  create mode 100644 drivers/fpga/tests/fake-fpga-region.c
>  create mode 100644 drivers/fpga/tests/fake-fpga-region.h
> 
> diff --git a/drivers/fpga/tests/fake-fpga-region.c b/drivers/fpga/tests/fake-fpga-region.c
> new file mode 100644
> index 000000000000..b23ae5e94fe6
> --- /dev/null
> +++ b/drivers/fpga/tests/fake-fpga-region.c
> @@ -0,0 +1,259 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for the fake FPGA region
> + *
> + * Copyright (C) 2023 Red Hat, Inc.
> + *
> + * Author: Marco Pagani <marpagan@redhat.com>
> + */
> +
> +#include <linux/device.h>
> +#include <linux/list.h>
> +#include <linux/platform_device.h>
> +#include <linux/fpga/fpga-mgr.h>
> +#include <linux/fpga/fpga-region.h>
> +#include <linux/fpga/fpga-bridge.h>
> +#include <kunit/test.h>
> +
> +#include "fake-fpga-region.h"
> +
> +#define FAKE_FPGA_REGION_DEV_NAME	"fake_fpga_region"
> +
> +struct fake_region_priv {
> +	int id;
> +	struct kunit *test;
> +	struct list_head bridge_list;
> +};
> +
> +struct bridge_elem {
> +	struct fpga_bridge *bridge;
> +	struct list_head node;
> +};
> +
> +struct fake_region_data {
> +	struct fpga_manager *mgr;
> +	struct kunit *test;
> +};
> +
> +/**
> + * fake_fpga_region_register() - register a fake FPGA region.
> + * @mgr: associated FPGA manager.
> + * @parent: parent device.
> + * @test: KUnit test context object.
> + *
> + * Return: pointer to a new fake FPGA region on success, an ERR_PTR() encoded
> + * error code on failure.
> + */
> +struct fake_fpga_region *
> +fake_fpga_region_register(struct fpga_manager *mgr, struct device *parent,
> +			  struct kunit *test)
> +{
> +	struct fake_fpga_region *region_ctx;
> +	struct fake_region_data pdata;
> +	struct fake_region_priv *priv;
> +	int ret;
> +
> +	region_ctx = kzalloc(sizeof(*region_ctx), GFP_KERNEL);
> +	if (!region_ctx) {
> +		ret = -ENOMEM;
> +		goto err_mem;
> +	}
> +
> +	region_ctx->pdev = platform_device_alloc(FAKE_FPGA_REGION_DEV_NAME,
> +						 PLATFORM_DEVID_AUTO);
> +	if (!region_ctx->pdev) {
> +		pr_err("Fake FPGA region device allocation failed\n");
> +		ret = -ENOMEM;
> +		goto err_mem;
> +	}
> +
> +	pdata.mgr = mgr;
> +	pdata.test = test;
> +	platform_device_add_data(region_ctx->pdev, &pdata, sizeof(pdata));
> +
> +	region_ctx->pdev->dev.parent = parent;
> +	ret = platform_device_add(region_ctx->pdev);
> +	if (ret) {
> +		pr_err("Fake FPGA region device add failed\n");
> +		goto err_pdev;
> +	}
> +
> +	region_ctx->region = platform_get_drvdata(region_ctx->pdev);
> +
> +	if (test) {
> +		priv = region_ctx->region->priv;
> +		kunit_info(test, "Fake FPGA region %d registered\n", priv->id);
> +	}
> +
> +	return region_ctx;
> +
> +err_pdev:
> +	platform_device_put(region_ctx->pdev);
> +	kfree(region_ctx);
> +err_mem:
> +	return ERR_PTR(ret);
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_region_register);
> +
> +/**
> + * fake_fpga_region_unregister() - unregister a fake FPGA region.
> + * @region_ctx: fake FPGA region context data structure.
> + */
> +void fake_fpga_region_unregister(struct fake_fpga_region *region_ctx)
> +{
> +	struct fake_region_priv *priv;
> +	struct kunit *test;
> +	int id;
> +
> +	if (!region_ctx)
> +		return;
> +
> +	priv = region_ctx->region->priv;
> +	test = priv->test;
> +	id = priv->id;
> +
> +	if (region_ctx->pdev) {
> +		platform_device_unregister(region_ctx->pdev);
> +		if (test)
> +			kunit_info(test, "Fake FPGA region %d unregistered\n", id);
> +	}
> +
> +	kfree(region_ctx);
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_region_unregister);
> +
> +/**
> + * fake_fpga_region_add_bridge() - add a bridge to a fake FPGA region.
> + * @region_ctx: fake FPGA region context data structure.
> + * @bridge: FPGA bridge.
> + *
> + * Return: 0 if registration succeeded, an error code otherwise.
> + */
> +int fake_fpga_region_add_bridge(struct fake_fpga_region *region_ctx,
> +				struct fpga_bridge *bridge)
> +{
> +	struct fake_region_priv *priv;
> +	struct bridge_elem *elem;
> +
> +	priv = region_ctx->region->priv;
> +
> +	elem = devm_kzalloc(&region_ctx->pdev->dev, sizeof(*elem), GFP_KERNEL);
> +	if (!elem)
> +		return -ENOMEM;
> +
> +	/* Add bridge to the list of bridges in the private context */
> +	elem->bridge = bridge;
> +	list_add(&elem->node, &priv->bridge_list);
> +
> +	if (priv->test)
> +		kunit_info(priv->test, "Bridge added to fake FPGA region %d\n",
> +			   priv->id);
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_region_add_bridge);

To move these exported functions out of fake driver, could we also provide
the bridge list in platform_data?

Thanks,
Yilun

> +
> +int fake_fpga_region_program(struct fake_fpga_region *region_ctx)
> +{
> +	int ret;
> +
> +	ret = fpga_region_program_fpga(region_ctx->region);
> +
> +	/* fpga_region_program_fpga() already puts the bridges in case of errors */
> +	if (!ret)
> +		fpga_bridges_put(&region_ctx->region->bridge_list);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_region_program);
> +
> +static int fake_region_get_bridges(struct fpga_region *region)
> +{
> +	struct fake_region_priv *priv;
> +	struct bridge_elem *elem;
> +	int ret;
> +
> +	priv = region->priv;
> +
> +	/* Copy the list of bridges from the private context to the region */
> +	list_for_each_entry(elem, &priv->bridge_list, node) {
> +		ret = fpga_bridge_get_to_list(elem->bridge->dev.parent,
> +					      region->info,
> +					      &region->bridge_list);
> +		if (ret)
> +			break;
> +	}
> +
> +	return ret;
> +}
> +
> +static int fake_fpga_region_probe(struct platform_device *pdev)
> +{
> +	struct device *dev;
> +	struct fpga_region *region;
> +	struct fpga_manager *mgr;
> +	struct fake_region_data *pdata;
> +	struct fake_region_priv *priv;
> +	struct fpga_region_info info;
> +	static int id_count;
> +
> +	dev = &pdev->dev;
> +	pdata = dev_get_platdata(dev);
> +
> +	if (!pdata) {
> +		dev_err(&pdev->dev, "Missing platform data\n");
> +		return -EINVAL;
> +	}
> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	mgr = fpga_mgr_get(pdata->mgr->dev.parent);
> +	if (IS_ERR(mgr))
> +		return PTR_ERR(mgr);
> +
> +	INIT_LIST_HEAD(&priv->bridge_list);
> +	priv->id = id_count++;
> +	priv->test = pdata->test;
> +
> +	memset(&info, 0, sizeof(info));
> +	info.priv = priv;
> +	info.mgr = mgr;
> +	info.get_bridges = fake_region_get_bridges;
> +
> +	region = fpga_region_register_full(dev, &info);
> +	if (IS_ERR(region)) {
> +		fpga_mgr_put(mgr);
> +		return PTR_ERR(region);
> +	}
> +
> +	platform_set_drvdata(pdev, region);
> +
> +	return 0;
> +}
> +
> +static int fake_fpga_region_remove(struct platform_device *pdev)
> +{
> +	struct fpga_region *region = platform_get_drvdata(pdev);
> +	struct fpga_manager *mgr = region->mgr;
> +
> +	fpga_mgr_put(mgr);
> +	fpga_region_unregister(region);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver fake_fpga_region_drv = {
> +	.driver = {
> +		.name = FAKE_FPGA_REGION_DEV_NAME
> +	},
> +	.probe = fake_fpga_region_probe,
> +	.remove = fake_fpga_region_remove,
> +};
> +
> +module_platform_driver(fake_fpga_region_drv);
> +
> +MODULE_AUTHOR("Marco Pagani <marpagan@redhat.com>");
> +MODULE_DESCRIPTION("Fake FPGA Bridge");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/fpga/tests/fake-fpga-region.h b/drivers/fpga/tests/fake-fpga-region.h
> new file mode 100644
> index 000000000000..976982c192bc
> --- /dev/null
> +++ b/drivers/fpga/tests/fake-fpga-region.h
> @@ -0,0 +1,40 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Header file for the fake FPGA region
> + *
> + * Copyright (C) 2023 Red Hat, Inc.
> + *
> + * Author: Marco Pagani <marpagan@redhat.com>
> + */
> +
> +#ifndef __FPGA_FAKE_RGN_H
> +#define __FPGA_FAKE_RGN_H
> +
> +#include <linux/platform_device.h>
> +#include <kunit/test.h>
> +#include <linux/fpga/fpga-mgr.h>
> +#include <linux/fpga/fpga-bridge.h>
> +
> +/**
> + * struct fake_fpga_region - fake FPGA region context data structure
> + *
> + * @region: FPGA region.
> + * @pdev: platform device of the FPGA region.
> + */
> +struct fake_fpga_region {
> +	struct fpga_region *region;
> +	struct platform_device *pdev;
> +};
> +
> +struct fake_fpga_region *
> +fake_fpga_region_register(struct fpga_manager *mgr, struct device *parent,
> +			  struct kunit *test);
> +
> +int fake_fpga_region_add_bridge(struct fake_fpga_region *region_ctx,
> +				struct fpga_bridge *bridge);
> +
> +int fake_fpga_region_program(struct fake_fpga_region *region_ctx);
> +
> +void fake_fpga_region_unregister(struct fake_fpga_region *region_ctx);
> +
> +#endif /* __FPGA_FAKE_RGN_H */
> -- 
> 2.39.2
> 

Re: [RFC PATCH v4 3/4] fpga: add fake FPGA region

[Marco Pagani]

On 2023-04-20 20:38, Xu Yilun wrote:
> On 2023-04-17 at 14:23:07 +0200, Marco Pagani wrote:
>> Add fake FPGA region platform driver with support functions. This
>> module is part of the KUnit tests for the FPGA subsystem.
>>
>> Signed-off-by: Marco Pagani <marpagan@redhat.com>
>> ---
>>  drivers/fpga/tests/fake-fpga-region.c | 259 ++++++++++++++++++++++++++
>>  drivers/fpga/tests/fake-fpga-region.h |  40 ++++
>>  2 files changed, 299 insertions(+)
>>  create mode 100644 drivers/fpga/tests/fake-fpga-region.c
>>  create mode 100644 drivers/fpga/tests/fake-fpga-region.h
>>
>> diff --git a/drivers/fpga/tests/fake-fpga-region.c b/drivers/fpga/tests/fake-fpga-region.c
>> new file mode 100644
>> index 000000000000..b23ae5e94fe6
>> --- /dev/null
>> +++ b/drivers/fpga/tests/fake-fpga-region.c
>> @@ -0,0 +1,259 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Driver for the fake FPGA region
>> + *
>> + * Copyright (C) 2023 Red Hat, Inc.
>> + *
>> + * Author: Marco Pagani <marpagan@redhat.com>
>> + */
>> +
>> +#include <linux/device.h>
>> +#include <linux/list.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/fpga/fpga-mgr.h>
>> +#include <linux/fpga/fpga-region.h>
>> +#include <linux/fpga/fpga-bridge.h>
>> +#include <kunit/test.h>
>> +
>> +#include "fake-fpga-region.h"
>> +
>> +#define FAKE_FPGA_REGION_DEV_NAME	"fake_fpga_region"
>> +
>> +struct fake_region_priv {
>> +	int id;
>> +	struct kunit *test;
>> +	struct list_head bridge_list;
>> +};
>> +
>> +struct bridge_elem {
>> +	struct fpga_bridge *bridge;
>> +	struct list_head node;
>> +};
>> +
>> +struct fake_region_data {
>> +	struct fpga_manager *mgr;
>> +	struct kunit *test;
>> +};
>> +
>> +/**
>> + * fake_fpga_region_register() - register a fake FPGA region.
>> + * @mgr: associated FPGA manager.
>> + * @parent: parent device.
>> + * @test: KUnit test context object.
>> + *
>> + * Return: pointer to a new fake FPGA region on success, an ERR_PTR() encoded
>> + * error code on failure.
>> + */
>> +struct fake_fpga_region *
>> +fake_fpga_region_register(struct fpga_manager *mgr, struct device *parent,
>> +			  struct kunit *test)
>> +{
>> +	struct fake_fpga_region *region_ctx;
>> +	struct fake_region_data pdata;
>> +	struct fake_region_priv *priv;
>> +	int ret;
>> +
>> +	region_ctx = kzalloc(sizeof(*region_ctx), GFP_KERNEL);
>> +	if (!region_ctx) {
>> +		ret = -ENOMEM;
>> +		goto err_mem;
>> +	}
>> +
>> +	region_ctx->pdev = platform_device_alloc(FAKE_FPGA_REGION_DEV_NAME,
>> +						 PLATFORM_DEVID_AUTO);
>> +	if (!region_ctx->pdev) {
>> +		pr_err("Fake FPGA region device allocation failed\n");
>> +		ret = -ENOMEM;
>> +		goto err_mem;
>> +	}
>> +
>> +	pdata.mgr = mgr;
>> +	pdata.test = test;
>> +	platform_device_add_data(region_ctx->pdev, &pdata, sizeof(pdata));
>> +
>> +	region_ctx->pdev->dev.parent = parent;
>> +	ret = platform_device_add(region_ctx->pdev);
>> +	if (ret) {
>> +		pr_err("Fake FPGA region device add failed\n");
>> +		goto err_pdev;
>> +	}
>> +
>> +	region_ctx->region = platform_get_drvdata(region_ctx->pdev);
>> +
>> +	if (test) {
>> +		priv = region_ctx->region->priv;
>> +		kunit_info(test, "Fake FPGA region %d registered\n", priv->id);
>> +	}
>> +
>> +	return region_ctx;
>> +
>> +err_pdev:
>> +	platform_device_put(region_ctx->pdev);
>> +	kfree(region_ctx);
>> +err_mem:
>> +	return ERR_PTR(ret);
>> +}
>> +EXPORT_SYMBOL_GPL(fake_fpga_region_register);
>> +
>> +/**
>> + * fake_fpga_region_unregister() - unregister a fake FPGA region.
>> + * @region_ctx: fake FPGA region context data structure.
>> + */
>> +void fake_fpga_region_unregister(struct fake_fpga_region *region_ctx)
>> +{
>> +	struct fake_region_priv *priv;
>> +	struct kunit *test;
>> +	int id;
>> +
>> +	if (!region_ctx)
>> +		return;
>> +
>> +	priv = region_ctx->region->priv;
>> +	test = priv->test;
>> +	id = priv->id;
>> +
>> +	if (region_ctx->pdev) {
>> +		platform_device_unregister(region_ctx->pdev);
>> +		if (test)
>> +			kunit_info(test, "Fake FPGA region %d unregistered\n", id);
>> +	}
>> +
>> +	kfree(region_ctx);
>> +}
>> +EXPORT_SYMBOL_GPL(fake_fpga_region_unregister);
>> +
>> +/**
>> + * fake_fpga_region_add_bridge() - add a bridge to a fake FPGA region.
>> + * @region_ctx: fake FPGA region context data structure.
>> + * @bridge: FPGA bridge.
>> + *
>> + * Return: 0 if registration succeeded, an error code otherwise.
>> + */
>> +int fake_fpga_region_add_bridge(struct fake_fpga_region *region_ctx,
>> +				struct fpga_bridge *bridge)
>> +{
>> +	struct fake_region_priv *priv;
>> +	struct bridge_elem *elem;
>> +
>> +	priv = region_ctx->region->priv;
>> +
>> +	elem = devm_kzalloc(&region_ctx->pdev->dev, sizeof(*elem), GFP_KERNEL);
>> +	if (!elem)
>> +		return -ENOMEM;
>> +
>> +	/* Add bridge to the list of bridges in the private context */
>> +	elem->bridge = bridge;
>> +	list_add(&elem->node, &priv->bridge_list);
>> +
>> +	if (priv->test)
>> +		kunit_info(priv->test, "Bridge added to fake FPGA region %d\n",
>> +			   priv->id);
>> +
>> +	return 0;
>> +}
>> +EXPORT_SYMBOL_GPL(fake_fpga_region_add_bridge);
> 
> To move these exported functions out of fake driver, could we also provide
> the bridge list in platform_data?
> 
> Thanks,
> Yilun

I feel that the function for adding bridges to the fake region should belong
to the region driver itself rather than the fpga-test module. However, I can
certainly include the bridge list also in platform_data.

Thanks,
Marco


> 
>> +
>> +int fake_fpga_region_program(struct fake_fpga_region *region_ctx)
>> +{
>> +	int ret;
>> +
>> +	ret = fpga_region_program_fpga(region_ctx->region);
>> +
>> +	/* fpga_region_program_fpga() already puts the bridges in case of errors */
>> +	if (!ret)
>> +		fpga_bridges_put(&region_ctx->region->bridge_list);
>> +
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(fake_fpga_region_program);
>> +
>> +static int fake_region_get_bridges(struct fpga_region *region)
>> +{
>> +	struct fake_region_priv *priv;
>> +	struct bridge_elem *elem;
>> +	int ret;
>> +
>> +	priv = region->priv;
>> +
>> +	/* Copy the list of bridges from the private context to the region */
>> +	list_for_each_entry(elem, &priv->bridge_list, node) {
>> +		ret = fpga_bridge_get_to_list(elem->bridge->dev.parent,
>> +					      region->info,
>> +					      &region->bridge_list);
>> +		if (ret)
>> +			break;
>> +	}
>> +
>> +	return ret;
>> +}
>> +
>> +static int fake_fpga_region_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev;
>> +	struct fpga_region *region;
>> +	struct fpga_manager *mgr;
>> +	struct fake_region_data *pdata;
>> +	struct fake_region_priv *priv;
>> +	struct fpga_region_info info;
>> +	static int id_count;
>> +
>> +	dev = &pdev->dev;
>> +	pdata = dev_get_platdata(dev);
>> +
>> +	if (!pdata) {
>> +		dev_err(&pdev->dev, "Missing platform data\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>> +	if (!priv)
>> +		return -ENOMEM;
>> +
>> +	mgr = fpga_mgr_get(pdata->mgr->dev.parent);
>> +	if (IS_ERR(mgr))
>> +		return PTR_ERR(mgr);
>> +
>> +	INIT_LIST_HEAD(&priv->bridge_list);
>> +	priv->id = id_count++;
>> +	priv->test = pdata->test;
>> +
>> +	memset(&info, 0, sizeof(info));
>> +	info.priv = priv;
>> +	info.mgr = mgr;
>> +	info.get_bridges = fake_region_get_bridges;
>> +
>> +	region = fpga_region_register_full(dev, &info);
>> +	if (IS_ERR(region)) {
>> +		fpga_mgr_put(mgr);
>> +		return PTR_ERR(region);
>> +	}
>> +
>> +	platform_set_drvdata(pdev, region);
>> +
>> +	return 0;
>> +}
>> +
>> +static int fake_fpga_region_remove(struct platform_device *pdev)
>> +{
>> +	struct fpga_region *region = platform_get_drvdata(pdev);
>> +	struct fpga_manager *mgr = region->mgr;
>> +
>> +	fpga_mgr_put(mgr);
>> +	fpga_region_unregister(region);
>> +
>> +	return 0;
>> +}
>> +
>> +static struct platform_driver fake_fpga_region_drv = {
>> +	.driver = {
>> +		.name = FAKE_FPGA_REGION_DEV_NAME
>> +	},
>> +	.probe = fake_fpga_region_probe,
>> +	.remove = fake_fpga_region_remove,
>> +};
>> +
>> +module_platform_driver(fake_fpga_region_drv);
>> +
>> +MODULE_AUTHOR("Marco Pagani <marpagan@redhat.com>");
>> +MODULE_DESCRIPTION("Fake FPGA Bridge");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/drivers/fpga/tests/fake-fpga-region.h b/drivers/fpga/tests/fake-fpga-region.h
>> new file mode 100644
>> index 000000000000..976982c192bc
>> --- /dev/null
>> +++ b/drivers/fpga/tests/fake-fpga-region.h
>> @@ -0,0 +1,40 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Header file for the fake FPGA region
>> + *
>> + * Copyright (C) 2023 Red Hat, Inc.
>> + *
>> + * Author: Marco Pagani <marpagan@redhat.com>
>> + */
>> +
>> +#ifndef __FPGA_FAKE_RGN_H
>> +#define __FPGA_FAKE_RGN_H
>> +
>> +#include <linux/platform_device.h>
>> +#include <kunit/test.h>
>> +#include <linux/fpga/fpga-mgr.h>
>> +#include <linux/fpga/fpga-bridge.h>
>> +
>> +/**
>> + * struct fake_fpga_region - fake FPGA region context data structure
>> + *
>> + * @region: FPGA region.
>> + * @pdev: platform device of the FPGA region.
>> + */
>> +struct fake_fpga_region {
>> +	struct fpga_region *region;
>> +	struct platform_device *pdev;
>> +};
>> +
>> +struct fake_fpga_region *
>> +fake_fpga_region_register(struct fpga_manager *mgr, struct device *parent,
>> +			  struct kunit *test);
>> +
>> +int fake_fpga_region_add_bridge(struct fake_fpga_region *region_ctx,
>> +				struct fpga_bridge *bridge);
>> +
>> +int fake_fpga_region_program(struct fake_fpga_region *region_ctx);
>> +
>> +void fake_fpga_region_unregister(struct fake_fpga_region *region_ctx);
>> +
>> +#endif /* __FPGA_FAKE_RGN_H */
>> -- 
>> 2.39.2
>>
> 

[RFC PATCH v4 4/4] fpga: add initial KUnit test suites

[Marco Pagani]

Introduce initial KUnit tests for the FPGA subsystem. Tests are
organized into three test suites. The first suite tests the FPGA
Manager. The second suite tests the FPGA Bridge. Finally, the last
test suite models a complete FPGA platform and tests static and
partial reconfiguration.

Signed-off-by: Marco Pagani <marpagan@redhat.com>
---
 drivers/fpga/Kconfig            |   2 +
 drivers/fpga/Makefile           |   3 +
 drivers/fpga/tests/.kunitconfig |   5 +
 drivers/fpga/tests/Kconfig      |  11 +
 drivers/fpga/tests/Makefile     |   6 +
 drivers/fpga/tests/fpga-test.c  | 479 ++++++++++++++++++++++++++++++++
 6 files changed, 506 insertions(+)
 create mode 100644 drivers/fpga/tests/.kunitconfig
 create mode 100644 drivers/fpga/tests/Kconfig
 create mode 100644 drivers/fpga/tests/Makefile
 create mode 100644 drivers/fpga/tests/fpga-test.c

diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index 0a00763b9f28..2f689ac4ba3a 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -276,4 +276,6 @@ config FPGA_MGR_LATTICE_SYSCONFIG_SPI
 	  FPGA manager driver support for Lattice FPGAs programming over slave
 	  SPI sysCONFIG interface.
 
+source "drivers/fpga/tests/Kconfig"
+
 endif # FPGA
diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index 72e554b4d2f7..352a2612623e 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -55,3 +55,6 @@ obj-$(CONFIG_FPGA_DFL_NIOS_INTEL_PAC_N3000)	+= dfl-n3000-nios.o
 
 # Drivers for FPGAs which implement DFL
 obj-$(CONFIG_FPGA_DFL_PCI)		+= dfl-pci.o
+
+# KUnit tests
+obj-$(CONFIG_FPGA_KUNIT_TESTS)		+= tests/
diff --git a/drivers/fpga/tests/.kunitconfig b/drivers/fpga/tests/.kunitconfig
new file mode 100644
index 000000000000..a1c2a2974c39
--- /dev/null
+++ b/drivers/fpga/tests/.kunitconfig
@@ -0,0 +1,5 @@
+CONFIG_KUNIT=y
+CONFIG_FPGA=y
+CONFIG_FPGA_REGION=y
+CONFIG_FPGA_BRIDGE=y
+CONFIG_FPGA_KUNIT_TESTS=y
diff --git a/drivers/fpga/tests/Kconfig b/drivers/fpga/tests/Kconfig
new file mode 100644
index 000000000000..1cbea75dd29b
--- /dev/null
+++ b/drivers/fpga/tests/Kconfig
@@ -0,0 +1,11 @@
+config FPGA_KUNIT_TESTS
+	tristate "KUnit test for the FPGA subsystem" if !KUNIT_ALL_TESTS
+	depends on FPGA && FPGA_REGION && FPGA_BRIDGE && KUNIT
+	default KUNIT_ALL_TESTS
+        help
+          This builds unit tests for the FPGA subsystem
+
+          For more information on KUnit and unit tests in general,
+          please refer to the KUnit documentation in Documentation/dev-tools/kunit/.
+
+          If unsure, say N.
diff --git a/drivers/fpga/tests/Makefile b/drivers/fpga/tests/Makefile
new file mode 100644
index 000000000000..0b052570659b
--- /dev/null
+++ b/drivers/fpga/tests/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_FPGA_KUNIT_TESTS) += fake-fpga-mgr.o
+obj-$(CONFIG_FPGA_KUNIT_TESTS) += fake-fpga-region.o
+obj-$(CONFIG_FPGA_KUNIT_TESTS) += fake-fpga-bridge.o
+obj-$(CONFIG_FPGA_KUNIT_TESTS) += fpga-test.o
diff --git a/drivers/fpga/tests/fpga-test.c b/drivers/fpga/tests/fpga-test.c
new file mode 100644
index 000000000000..52e71ce07b27
--- /dev/null
+++ b/drivers/fpga/tests/fpga-test.c
@@ -0,0 +1,479 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit tests for the FPGA subsystem
+ *
+ * Copyright (C) 2023 Red Hat, Inc.
+ *
+ * Author: Marco Pagani <marpagan@redhat.com>
+ */
+
+#include <kunit/test.h>
+#include <linux/list.h>
+#include <linux/platform_device.h>
+#include <linux/scatterlist.h>
+
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/fpga/fpga-region.h>
+#include <linux/fpga/fpga-bridge.h>
+
+#include "fake-fpga-region.h"
+#include "fake-fpga-bridge.h"
+#include "fake-fpga-mgr.h"
+
+#define STATIC_IMG_BLOCKS	16
+#define STATIC_IMG_SIZE		(FPGA_IMG_BLOCK * STATIC_IMG_BLOCKS)
+
+#define PARTIAL_IMG_BLOCKS	4
+#define PARTIAL_IMG_SIZE	(FPGA_IMG_BLOCK * PARTIAL_IMG_BLOCKS)
+
+/**
+ * buf_img_alloc() - Allocate a fake FPGA image using a buffer.
+ * @test: KUnit test context object.
+ * @dev: owning device.
+ * @size: image size.
+ *
+ * Return: pointer to a struct fpga_image_info or NULL on failure.
+ */
+static struct fpga_image_info *buf_img_alloc(struct kunit *test, struct device *dev,
+					     size_t size)
+{
+	struct fpga_image_info *img_info;
+	char *img_buf;
+
+	img_buf = kunit_kzalloc(test, size, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, img_buf);
+	fake_fpga_mgr_fill_header(img_buf);
+
+	img_info = fpga_image_info_alloc(dev);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, img_info);
+
+	img_info->count = size;
+	img_info->buf = img_buf;
+
+	kunit_info(test, "FPGA image allocated in a buffer, size: %zu\n", size);
+
+	return img_info;
+}
+
+/**
+ * sgt_img_alloc() - Allocate a fake FPGA image using a scatter gather table.
+ * @test: KUnit test context object.
+ * @dev: owning device.
+ * @size: image size.
+ *
+ * Return: pointer to a struct fpga_image_info or NULL on failure.
+ */
+static struct fpga_image_info *sgt_img_alloc(struct kunit *test, struct device *dev,
+					     size_t size)
+{
+	struct fpga_image_info *img_info;
+	char *img_buf;
+	struct sg_table *sgt;
+	int ret;
+
+	img_buf = kunit_kzalloc(test, size, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, img_buf);
+	fake_fpga_mgr_fill_header(img_buf);
+
+	sgt = kunit_kzalloc(test, sizeof(*sgt), GFP_KERNEL);
+	ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+	sg_init_one(sgt->sgl, img_buf, size);
+
+	img_info = fpga_image_info_alloc(dev);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, img_info);
+
+	img_info->sgt = sgt;
+
+	kunit_info(test, "FPGA image allocated in a scatter gather table, size: %zu\n",
+		   size);
+
+	return img_info;
+}
+
+/**
+ * img_free() - Free a fake FPGA image
+ * @img_info: fpga image information struct.
+ *
+ */
+static void img_free(struct fpga_image_info *img_info)
+{
+	if (!img_info)
+		return;
+
+	if (img_info->sgt)
+		sg_free_table(img_info->sgt);
+
+	fpga_image_info_free(img_info);
+}
+
+static int fpga_mgr_test_init(struct kunit *test)
+{
+	struct fake_fpga_mgr *mgr_ctx;
+
+	mgr_ctx = fake_fpga_mgr_register(test, NULL);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(mgr_ctx));
+
+	test->priv = mgr_ctx;
+
+	return 0;
+}
+
+static void fpga_mgr_test_img_load_buf(struct kunit *test)
+{
+	struct fake_fpga_mgr *mgr_ctx;
+	struct fpga_image_info *img_info;
+	int ret;
+
+	mgr_ctx = test->priv;
+
+	/* Allocate an FPGA image using a buffer */
+	img_info = buf_img_alloc(test, &mgr_ctx->pdev->dev, STATIC_IMG_SIZE);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, img_info);
+
+	KUNIT_EXPECT_EQ(test, 0, fake_fpga_mgr_get_rcfg_count(mgr_ctx));
+
+	ret = fpga_mgr_load(mgr_ctx->mgr, img_info);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	fake_fpga_mgr_check_write_buf(mgr_ctx);
+
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_mgr_get_rcfg_count(mgr_ctx));
+
+	img_free(img_info);
+}
+
+static void fpga_mgr_test_img_load_sgt(struct kunit *test)
+{
+	struct fake_fpga_mgr *mgr_ctx;
+	struct fpga_image_info *img_info;
+	int ret;
+
+	mgr_ctx = test->priv;
+
+	/* Allocate an FPGA image using a scatter gather table */
+	img_info = sgt_img_alloc(test, &mgr_ctx->pdev->dev, STATIC_IMG_SIZE);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, img_info);
+
+	KUNIT_EXPECT_EQ(test, 0, fake_fpga_mgr_get_rcfg_count(mgr_ctx));
+
+	ret = fpga_mgr_load(mgr_ctx->mgr, img_info);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	fake_fpga_mgr_check_write_sgt(mgr_ctx);
+
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_mgr_get_rcfg_count(mgr_ctx));
+
+	img_free(img_info);
+}
+
+static void fpga_mgr_test_exit(struct kunit *test)
+{
+	struct fake_fpga_mgr *mgr_ctx;
+
+	mgr_ctx = test->priv;
+
+	if (mgr_ctx)
+		fake_fpga_mgr_unregister(mgr_ctx);
+}
+
+static struct kunit_case fpga_mgr_test_cases[] = {
+	KUNIT_CASE(fpga_mgr_test_img_load_buf),
+	KUNIT_CASE(fpga_mgr_test_img_load_sgt),
+	{}
+};
+
+static struct kunit_suite fpga_mgr_suite = {
+	.name = "fpga_mgr",
+	.init = fpga_mgr_test_init,
+	.exit = fpga_mgr_test_exit,
+	.test_cases = fpga_mgr_test_cases,
+};
+
+static int fpga_bridge_test_init(struct kunit *test)
+{
+	struct fake_fpga_bridge *bridge_ctx;
+
+	bridge_ctx = fake_fpga_bridge_register(NULL, test);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(bridge_ctx));
+
+	test->priv = bridge_ctx;
+
+	return 0;
+}
+
+static void fpga_bridge_test_exit(struct kunit *test)
+{
+	struct fake_fpga_bridge *bridge_ctx;
+
+	bridge_ctx = test->priv;
+
+	if (bridge_ctx)
+		fake_fpga_bridge_unregister(bridge_ctx);
+}
+
+static void fpga_bridge_test_toggle(struct kunit *test)
+{
+	struct fake_fpga_bridge *bridge_ctx;
+
+	bridge_ctx = test->priv;
+
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_bridge_get_state(bridge_ctx));
+
+	fpga_bridge_disable(bridge_ctx->bridge);
+	KUNIT_EXPECT_EQ(test, 0, fake_fpga_bridge_get_state(bridge_ctx));
+
+	fpga_bridge_enable(bridge_ctx->bridge);
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_bridge_get_state(bridge_ctx));
+}
+
+static void fpga_bridge_test_get_put_list(struct kunit *test)
+{
+	struct list_head bridge_list;
+	struct fake_fpga_bridge *bridge_0_ctx, *bridge_1_ctx;
+	int ret;
+
+	bridge_0_ctx = test->priv;
+
+	/* Register another bridge for this test */
+	bridge_1_ctx = fake_fpga_bridge_register(NULL, test);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(bridge_1_ctx));
+
+	INIT_LIST_HEAD(&bridge_list);
+
+	/* Get bridge_0 and add it to the list */
+	ret = fpga_bridge_get_to_list(bridge_1_ctx->bridge->dev.parent, NULL,
+				      &bridge_list);
+	KUNIT_EXPECT_EQ(test, ret, 0);
+
+	KUNIT_EXPECT_PTR_EQ(test, bridge_1_ctx->bridge,
+			    list_first_entry_or_null(&bridge_list, struct fpga_bridge, node));
+
+	/* Get bridge_1 and add it to the list */
+	ret = fpga_bridge_get_to_list(bridge_0_ctx->bridge->dev.parent, NULL,
+				      &bridge_list);
+	KUNIT_EXPECT_EQ(test, ret, 0);
+
+	KUNIT_EXPECT_PTR_EQ(test, bridge_0_ctx->bridge,
+			    list_first_entry_or_null(&bridge_list, struct fpga_bridge, node));
+
+	/* Put and remove both bridges from the list */
+	fpga_bridges_put(&bridge_list);
+
+	KUNIT_EXPECT_TRUE(test, list_empty(&bridge_list));
+
+	fake_fpga_bridge_unregister(bridge_1_ctx);
+}
+
+static struct kunit_case fpga_bridge_test_cases[] = {
+	KUNIT_CASE(fpga_bridge_test_toggle),
+	KUNIT_CASE(fpga_bridge_test_get_put_list),
+	{}
+};
+
+static struct kunit_suite fpga_bridge_suite = {
+	.name = "fpga_bridge",
+	.init = fpga_bridge_test_init,
+	.exit = fpga_bridge_test_exit,
+	.test_cases = fpga_bridge_test_cases,
+};
+
+struct fpga_base_ctx {
+	/*
+	 * Base FPGA layout consisting of a single region
+	 * controlled by a bridge and the FPGA manager
+	 */
+	struct fake_fpga_mgr *mgr_ctx;
+	struct fake_fpga_bridge *bridge_ctx;
+	struct fake_fpga_region *region_ctx;
+};
+
+static int fpga_test_init(struct kunit *test)
+{
+	struct fpga_base_ctx *base_ctx;
+	int ret;
+
+	base_ctx = kunit_kzalloc(test, sizeof(*base_ctx), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, base_ctx);
+	test->priv = base_ctx;
+
+	/* Build the base FPGA layout */
+	base_ctx->mgr_ctx = fake_fpga_mgr_register(test, NULL);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(base_ctx->mgr_ctx));
+
+	base_ctx->bridge_ctx = fake_fpga_bridge_register(NULL, test);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(base_ctx->bridge_ctx));
+
+	/* The base region a child of the base bridge */
+	base_ctx->region_ctx = fake_fpga_region_register(base_ctx->mgr_ctx->mgr,
+							 &base_ctx->bridge_ctx->bridge->dev, test);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(base_ctx->region_ctx));
+
+	ret = fake_fpga_region_add_bridge(base_ctx->region_ctx, base_ctx->bridge_ctx->bridge);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	kunit_info(test, "FPGA base system built\n");
+
+	KUNIT_EXPECT_EQ(test, 0, fake_fpga_mgr_get_rcfg_count(base_ctx->mgr_ctx));
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_bridge_get_state(base_ctx->bridge_ctx));
+	KUNIT_EXPECT_EQ(test, 0, fake_fpga_bridge_get_cycles_count(base_ctx->bridge_ctx));
+
+	return 0;
+}
+
+static void fpga_test_exit(struct kunit *test)
+{
+	struct fpga_base_ctx *base_ctx;
+
+	base_ctx = test->priv;
+
+	if (!base_ctx)
+		return;
+
+	if (base_ctx->region_ctx)
+		fake_fpga_region_unregister(base_ctx->region_ctx);
+
+	if (base_ctx->bridge_ctx)
+		fake_fpga_bridge_unregister(base_ctx->bridge_ctx);
+
+	if (base_ctx->mgr_ctx)
+		fake_fpga_mgr_unregister(base_ctx->mgr_ctx);
+}
+
+static void fpga_test_static_cfg(struct kunit *test)
+{
+	struct fpga_base_ctx *base_ctx;
+	struct fpga_image_info *buf_img_info;
+	struct fpga_image_info *sgt_img_info;
+	int ret;
+
+	base_ctx = test->priv;
+
+	buf_img_info = buf_img_alloc(test, &base_ctx->mgr_ctx->pdev->dev, STATIC_IMG_SIZE);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buf_img_info);
+
+	/* Configure the FPGA using the image in a buffer */
+	base_ctx->region_ctx->region->info = buf_img_info;
+	ret = fake_fpga_region_program(base_ctx->region_ctx);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	fake_fpga_mgr_check_write_buf(base_ctx->mgr_ctx);
+
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_mgr_get_rcfg_count(base_ctx->mgr_ctx));
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_bridge_get_state(base_ctx->bridge_ctx));
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_bridge_get_cycles_count(base_ctx->bridge_ctx));
+
+	kunit_info(test, "FPGA configuration completed using a buffer image\n");
+
+	sgt_img_info = sgt_img_alloc(test, &base_ctx->mgr_ctx->pdev->dev, STATIC_IMG_SIZE);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sgt_img_info);
+
+	/* Re-configure the FPGA using the image in a scatter list */
+	base_ctx->region_ctx->region->info = sgt_img_info;
+	ret = fake_fpga_region_program(base_ctx->region_ctx);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	fake_fpga_mgr_check_write_sgt(base_ctx->mgr_ctx);
+
+	KUNIT_EXPECT_EQ(test, 2, fake_fpga_mgr_get_rcfg_count(base_ctx->mgr_ctx));
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_bridge_get_state(base_ctx->bridge_ctx));
+	KUNIT_EXPECT_EQ(test, 2, fake_fpga_bridge_get_cycles_count(base_ctx->bridge_ctx));
+
+	kunit_info(test, "FPGA configuration completed using scatter gather table image\n");
+
+	img_free(sgt_img_info);
+}
+
+static void fpga_test_partial_rcfg(struct kunit *test)
+{
+	struct fpga_base_ctx *base_ctx;
+	struct fake_fpga_region *sub_region_0_ctx, *sub_region_1_ctx;
+	struct fake_fpga_bridge *sub_bridge_0_ctx, *sub_bridge_1_ctx;
+	struct fpga_image_info *partial_img_info;
+	int ret;
+
+	base_ctx = test->priv;
+
+	/*
+	 * Add two reconfigurable sub-regions, each controlled by a bridge. The
+	 * reconfigurable sub-region are children of their bridges which are,
+	 * in turn, children of the base region. For simplicity, the same image
+	 * is used to configure reconfigurable regions
+	 */
+	sub_bridge_0_ctx = fake_fpga_bridge_register(&base_ctx->region_ctx->region->dev,
+						     test);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(sub_bridge_0_ctx));
+
+	sub_region_0_ctx = fake_fpga_region_register(base_ctx->mgr_ctx->mgr,
+						     &sub_bridge_0_ctx->bridge->dev, test);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(sub_region_0_ctx));
+
+	ret = fake_fpga_region_add_bridge(sub_region_0_ctx, sub_bridge_0_ctx->bridge);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	sub_bridge_1_ctx = fake_fpga_bridge_register(&base_ctx->region_ctx->region->dev,
+						     test);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(sub_bridge_1_ctx));
+
+	sub_region_1_ctx = fake_fpga_region_register(base_ctx->mgr_ctx->mgr,
+						     &sub_bridge_1_ctx->bridge->dev, test);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(sub_region_1_ctx));
+
+	ret = fake_fpga_region_add_bridge(sub_region_1_ctx, sub_bridge_1_ctx->bridge);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	/* Allocate a partial image using a buffer */
+	partial_img_info = buf_img_alloc(test, &base_ctx->mgr_ctx->pdev->dev,
+					 PARTIAL_IMG_SIZE);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, partial_img_info);
+	partial_img_info->flags = FPGA_MGR_PARTIAL_RECONFIG;
+
+	/* Re-configure sub-region 0 with the partial image */
+	sub_region_0_ctx->region->info = partial_img_info;
+	ret = fake_fpga_region_program(sub_region_0_ctx);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	fake_fpga_mgr_check_write_buf(base_ctx->mgr_ctx);
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_mgr_get_rcfg_count(base_ctx->mgr_ctx));
+
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_bridge_get_state(sub_bridge_0_ctx));
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_bridge_get_cycles_count(sub_bridge_0_ctx));
+
+	/* Re-configure sub-region 1 with the partial image */
+	sub_region_1_ctx->region->info = partial_img_info;
+	ret = fake_fpga_region_program(sub_region_1_ctx);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	fake_fpga_mgr_check_write_buf(base_ctx->mgr_ctx);
+	KUNIT_EXPECT_EQ(test, 2, fake_fpga_mgr_get_rcfg_count(base_ctx->mgr_ctx));
+
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_bridge_get_state(sub_bridge_1_ctx));
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_bridge_get_cycles_count(sub_bridge_1_ctx));
+
+	/* Check that the base bridge has not been disabled during reconfiguration */
+	KUNIT_EXPECT_EQ(test, 1, fake_fpga_bridge_get_state(base_ctx->bridge_ctx));
+	KUNIT_EXPECT_EQ(test, 0, fake_fpga_bridge_get_cycles_count(base_ctx->bridge_ctx));
+
+	img_free(partial_img_info);
+	fake_fpga_region_unregister(sub_region_0_ctx);
+	fake_fpga_bridge_unregister(sub_bridge_0_ctx);
+	fake_fpga_region_unregister(sub_region_1_ctx);
+	fake_fpga_bridge_unregister(sub_bridge_1_ctx);
+}
+
+static struct kunit_case fpga_test_cases[] = {
+	KUNIT_CASE(fpga_test_static_cfg),
+	KUNIT_CASE(fpga_test_partial_rcfg),
+	{}
+};
+
+static struct kunit_suite fpga_suite = {
+	.name = "fpga",
+	.init = fpga_test_init,
+	.exit = fpga_test_exit,
+	.test_cases = fpga_test_cases,
+};
+
+kunit_test_suites(&fpga_mgr_suite, &fpga_bridge_suite, &fpga_suite);
+
+MODULE_LICENSE("GPL v2");
-- 
2.39.2