Re: [RFC PATCH v5 1/4] fpga: add fake FPGA manager

[Xu Yilun]

On 2023-05-11 at 16:19:19 +0200, Marco Pagani wrote:
> Add fake FPGA manager platform driver with support functions. This module
> is part of the KUnit tests for the FPGA subsystem.
> 
> Signed-off-by: Marco Pagani <marpagan@xxxxxxxxxx>
> ---
>  drivers/fpga/tests/fake-fpga-mgr.c | 271 +++++++++++++++++++++++++++++
>  drivers/fpga/tests/fake-fpga-mgr.h |  53 ++++++
>  2 files changed, 324 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..1e994db10159
> --- /dev/null
> +++ b/drivers/fpga/tests/fake-fpga-mgr.c
> @@ -0,0 +1,271 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for the fake FPGA manager
> + *
> + * Copyright (C) 2023 Red Hat, Inc.
> + *
> + * Author: Marco Pagani <marpagan@xxxxxxxxxx>
> + */
> +
> +#include <linux/types.h>
> +#include <linux/device.h>
> +#include <linux/platform_device.h>
> +#include <linux/fpga/fpga-mgr.h>
> +
> +#include "fake-fpga-mgr.h"
> +
> +#define FAKE_FPGA_MGR_DEV_NAME	"fake_fpga_mgr"
> +
> +struct fake_mgr_pdata {
> +	struct kunit *test;
> +	struct fake_fpga_mgr_stats *stats;
> +};
> +
> +struct fake_mgr_priv {
> +	int seq_num;
> +	struct fake_mgr_pdata *pdata;
> +};
> +
> +static bool check_header(struct kunit *test, const char *buf, size_t count)
> +{
> +	size_t i;
> +
> +	for (i = 0; i < count; i++)
> +		if (buf[i] != TEST_HEADER_MAGIC)
> +			return false;
> +
> +	return true;
> +}
> +
> +static enum fpga_mgr_states op_state(struct fpga_manager *mgr)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	kunit_info(priv->pdata->test, "Fake FPGA manager: state\n");
> +
> +	return mgr->state;
> +}
> +
> +static u64 op_status(struct fpga_manager *mgr)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	kunit_info(priv->pdata->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;
> +
> +	/* Set header_size and data_size as expected */
> +	info->header_size = TEST_HEADER_SIZE;
> +	info->data_size = info->count - TEST_HEADER_SIZE;
> +
> +	priv->pdata->stats->header_done = check_header(priv->pdata->test, buf,
> +						       info->header_size);
> +	priv->pdata->stats->op_parse_header_state = mgr->state;
> +	priv->pdata->stats->op_parse_header_seq = priv->seq_num++;
> +
> +	kunit_info(priv->pdata->test, "Fake FPGA manager: parse_header\n");
> +
> +	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;
> +
> +	priv->pdata->stats->op_write_init_state = mgr->state;
> +	priv->pdata->stats->op_write_init_seq = priv->seq_num++;
> +
> +	kunit_info(priv->pdata->test, "Fake FPGA manager: write_init\n");
> +
> +	return 0;
> +}
> +
> +static int op_write(struct fpga_manager *mgr, const char *buf, size_t count)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	priv->pdata->stats->op_write_state = mgr->state;
> +	priv->pdata->stats->op_write_seq = priv->seq_num++;
> +
> +	kunit_info(priv->pdata->test, "Fake FPGA manager: write\n");
> +
> +	return 0;
> +}
> +
> +static int op_write_sg(struct fpga_manager *mgr, struct sg_table *sgt)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	priv->pdata->stats->op_write_state = mgr->state;
> +	priv->pdata->stats->op_write_seq = priv->seq_num++;
> +
> +	kunit_info(priv->pdata->test, "Fake FPGA manager: write_sg\n");
> +
> +	return 0;
> +}
> +
> +static int op_write_complete(struct fpga_manager *mgr, struct fpga_image_info *info)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	priv->pdata->stats->op_write_complete_state = mgr->state;
> +	priv->pdata->stats->op_write_complete_seq = priv->seq_num++;
> +	priv->pdata->stats->prog_count++;
> +
> +	kunit_info(priv->pdata->test, "Fake FPGA manager: write_complete\n");
> +
> +	return 0;
> +}
> +
> +static void op_fpga_remove(struct fpga_manager *mgr)
> +{
> +	struct fake_mgr_priv *priv;
> +
> +	priv = mgr->priv;
> +
> +	kunit_info(priv->pdata->test, "Fake FPGA manager: remove\n");
> +}
> +
> +static const struct fpga_manager_ops fake_fpga_mgr_ops = {
> +	.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.
> + * @test: KUnit test context object.
> + * @mgr_ctx: fake FPGA manager context data structure.
> + *
> + * 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_pdata pdata;
> +	int ret;
> +
> +	mgr_ctx = kunit_kzalloc(test, 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) {
> +		kunit_err(test, "Fake FPGA manager device allocation failed\n");
> +		ret = -ENOMEM;
> +		goto err_mem;
> +	}
> +
> +	pdata.test = test;
> +	pdata.stats = &mgr_ctx->stats;
> +	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) {
> +		kunit_err(test, "Fake FPGA manager device add failed\n");
> +		goto err_pdev;
> +	}

Is it possible also move this function in fpga-test?

> +
> +	mgr_ctx->mgr = platform_get_drvdata(mgr_ctx->pdev);

If moved out, platform_get_drvdata() from outside the driver is not a
good idea, maybe use class_find_device() to find the mgr out.

> +
> +	kunit_info(test, "Fake FPGA manager registered\n");
> +
> +	return mgr_ctx;
> +
> +err_pdev:
> +	platform_device_put(mgr_ctx->pdev);
> +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->pdata->test;
> +
> +	platform_device_unregister(mgr_ctx->pdev);
> +
> +	kunit_info(test, "Fake FPGA manager unregistered\n");
> +}
> +EXPORT_SYMBOL_GPL(fake_fpga_mgr_unregister);
> +
> +static int fake_fpga_mgr_probe(struct platform_device *pdev)
> +{
> +	struct device *dev;
> +	struct fake_mgr_pdata *pdata;
> +	struct fpga_manager *mgr;
> +	struct fake_mgr_priv *priv;
> +
> +	dev = &pdev->dev;
> +	pdata = dev_get_platdata(dev);
> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	priv->pdata = pdata;
> +
> +	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_LICENSE("GPL");
> diff --git a/drivers/fpga/tests/fake-fpga-mgr.h b/drivers/fpga/tests/fake-fpga-mgr.h
> new file mode 100644
> index 000000000000..282c20d8e40c
> --- /dev/null
> +++ b/drivers/fpga/tests/fake-fpga-mgr.h
> @@ -0,0 +1,53 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Header file for the fake FPGA manager
> + *
> + * Copyright (C) 2023 Red Hat, Inc.
> + *
> + * Author: Marco Pagani <marpagan@xxxxxxxxxx>
> + */
> +
> +#ifndef __FPGA_FAKE_MGR_H
> +#define __FPGA_FAKE_MGR_H
> +
> +#include <linux/types.h>
> +#include <linux/platform_device.h>
> +#include <kunit/test.h>
> +#include <linux/fpga/fpga-mgr.h>
> +
> +#define FPGA_IMG_BLOCK		1024
> +#define TEST_HEADER_MAGIC	0x3f
> +#define TEST_HEADER_SIZE	FPGA_IMG_BLOCK
> +
> +struct fake_fpga_mgr_stats {
> +	u32 prog_count;
> +	bool header_done;
> +	u32 op_parse_header_seq;
> +	u32 op_write_init_seq;
> +	u32 op_write_seq;
> +	u32 op_write_complete_seq;
> +	enum fpga_mgr_states op_parse_header_state;
> +	enum fpga_mgr_states op_write_init_state;
> +	enum fpga_mgr_states op_write_state;
> +	enum fpga_mgr_states op_write_complete_state;
> +};
> +
> +/**
> + * struct fake_fpga_mgr - fake FPGA manager context data structure
> + *
> + * @mgr: FPGA manager.
> + * @pdev: platform device of the FPGA manager.
> + * @stats: info from the low level driver.
> + */
> +struct fake_fpga_mgr {
> +	struct fpga_manager *mgr;
> +	struct platform_device *pdev;
> +	struct fake_fpga_mgr_stats stats;
> +};
> +
> +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);
> +
> +#endif /* __FPGA_FAKE_MGR_H */
> -- 
> 2.40.1
>