Re: [PATCH v6 18/29] fpga: dfl: add fpga manager platform driver for FME

[Moritz Fischer]

Hi Hao,

small nit below, looks good otherwise.

On Tue, Jun 12, 2018 at 06:10:32PM +0800, Wu Hao wrote:
> This patch adds fpga manager driver for FPGA Management Engine (FME). It
> implements fpga_manager_ops for FPGA Partial Reconfiguration function.
> 
> Signed-off-by: Tim Whisonant <tim.whisonant@xxxxxxxxx>
> Signed-off-by: Enno Luebbers <enno.luebbers@xxxxxxxxx>
> Signed-off-by: Shiva Rao <shiva.rao@xxxxxxxxx>
> Signed-off-by: Christopher Rauer <christopher.rauer@xxxxxxxxx>
> Signed-off-by: Kang Luwei <luwei.kang@xxxxxxxxx>
> Signed-off-by: Xiao Guangrong <guangrong.xiao@xxxxxxxxxxxxxxx>
> Signed-off-by: Wu Hao <hao.wu@xxxxxxxxx>
> Acked-by: Alan Tull <atull@xxxxxxxxxx>
> ---
> v3: rename driver to dfl-fpga-fme-mgr
>     implemented status callback for fpga manager
>     rebased due to fpga api changes
> v4: rename to dfl-fme-mgr, and fix SPDX license issue
>     add pr_credit comments and improve dev_err message
>     remove interface_id sysfs interface
>     include dfl-fme-pr.h instead of dfl.h
> v5: move related register definition from dfl-fme-pr.h to dfl-fme-mgr.c
>     use mapped ioaddr passed via pdata for register access.
>     rebase due to fpga manager API changes.
>     include header file for readq/writeq.
> v6: rebase, fix copyright time and add Acked-by from Alan.
> ---
>  drivers/fpga/Kconfig       |   6 +
>  drivers/fpga/Makefile      |   1 +
>  drivers/fpga/dfl-fme-mgr.c | 334 +++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 341 insertions(+)
>  create mode 100644 drivers/fpga/dfl-fme-mgr.c
> 
> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> index 45e9220..ca97f3c 100644
> --- a/drivers/fpga/Kconfig
> +++ b/drivers/fpga/Kconfig
> @@ -156,6 +156,12 @@ config FPGA_DFL_FME
>  	  FPGA platform level management features. There shall be 1 FME
>  	  per DFL based FPGA device.
>  
> +config FPGA_DFL_FME_MGR
> +	tristate "FPGA DFL FME Manager Driver"
> +	depends on FPGA_DFL_FME
> +	help
> +	  Say Y to enable FPGA Manager driver for FPGA Management Engine.
> +
>  config FPGA_DFL_PCI
>  	tristate "FPGA DFL PCIe Device Driver"
>  	depends on PCI && FPGA_DFL
> diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
> index fd334d40..23f41b0 100644
> --- a/drivers/fpga/Makefile
> +++ b/drivers/fpga/Makefile
> @@ -32,6 +32,7 @@ obj-$(CONFIG_OF_FPGA_REGION)		+= of-fpga-region.o
>  # FPGA Device Feature List Support
>  obj-$(CONFIG_FPGA_DFL)			+= dfl.o
>  obj-$(CONFIG_FPGA_DFL_FME)		+= dfl-fme.o
> +obj-$(CONFIG_FPGA_DFL_FME_MGR)		+= dfl-fme-mgr.o
>  
>  dfl-fme-objs := dfl-fme-main.o dfl-fme-pr.o
>  
> diff --git a/drivers/fpga/dfl-fme-mgr.c b/drivers/fpga/dfl-fme-mgr.c
> new file mode 100644
> index 0000000..be0060a
> --- /dev/null
> +++ b/drivers/fpga/dfl-fme-mgr.c
> @@ -0,0 +1,334 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * FPGA Manager Driver for FPGA Management Engine (FME)
> + *
> + * Copyright (C) 2017-2018 Intel Corporation, Inc.
> + *
> + * Authors:
> + *   Kang Luwei <luwei.kang@xxxxxxxxx>
> + *   Xiao Guangrong <guangrong.xiao@xxxxxxxxxxxxxxx>
> + *   Wu Hao <hao.wu@xxxxxxxxx>
> + *   Joseph Grecco <joe.grecco@xxxxxxxxx>
> + *   Enno Luebbers <enno.luebbers@xxxxxxxxx>
> + *   Tim Whisonant <tim.whisonant@xxxxxxxxx>
> + *   Ananda Ravuri <ananda.ravuri@xxxxxxxxx>
> + *   Christopher Rauer <christopher.rauer@xxxxxxxxx>
> + *   Henry Mitchel <henry.mitchel@xxxxxxxxx>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/module.h>
> +#include <linux/iopoll.h>
> +#include <linux/io-64-nonatomic-lo-hi.h>
> +#include <linux/fpga/fpga-mgr.h>
> +
> +#include "dfl-fme-pr.h"
> +
> +/* FME Partial Reconfiguration Sub Feature Register Set */
> +#define FME_PR_DFH		0x0
> +#define FME_PR_CTRL		0x8
> +#define FME_PR_STS		0x10
> +#define FME_PR_DATA		0x18
> +#define FME_PR_ERR		0x20
> +#define FME_PR_INTFC_ID_H	0xA8
> +#define FME_PR_INTFC_ID_L	0xB0
> +
> +/* FME PR Control Register Bitfield */
> +#define FME_PR_CTRL_PR_RST	BIT_ULL(0)  /* Reset PR engine */
> +#define FME_PR_CTRL_PR_RSTACK	BIT_ULL(4)  /* Ack for PR engine reset */
> +#define FME_PR_CTRL_PR_RGN_ID	GENMASK_ULL(9, 7)       /* PR Region ID */
> +#define FME_PR_CTRL_PR_START	BIT_ULL(12) /* Start to request PR service */
> +#define FME_PR_CTRL_PR_COMPLETE	BIT_ULL(13) /* PR data push completion */
> +
> +/* FME PR Status Register Bitfield */
> +/* Number of available entries in HW queue inside the PR engine. */
> +#define FME_PR_STS_PR_CREDIT	GENMASK_ULL(8, 0)
> +#define FME_PR_STS_PR_STS	BIT_ULL(16) /* PR operation status */
> +#define FME_PR_STS_PR_STS_IDLE	0
> +#define FME_PR_STS_PR_CTRLR_STS	GENMASK_ULL(22, 20)     /* Controller status */
> +#define FME_PR_STS_PR_HOST_STS	GENMASK_ULL(27, 24)     /* PR host status */
> +
> +/* FME PR Data Register Bitfield */
> +/* PR data from the raw-binary file. */
> +#define FME_PR_DATA_PR_DATA_RAW	GENMASK_ULL(32, 0)
> +
> +/* FME PR Error Register */
> +/* PR Operation errors detected. */
> +#define FME_PR_ERR_OPERATION_ERR	BIT_ULL(0)
> +/* CRC error detected. */
> +#define FME_PR_ERR_CRC_ERR		BIT_ULL(1)
> +/* Incompatible PR bitstream detected. */
> +#define FME_PR_ERR_INCOMPATIBLE_BS	BIT_ULL(2)
> +/* PR data push protocol violated. */
> +#define FME_PR_ERR_PROTOCOL_ERR		BIT_ULL(3)
> +/* PR data fifo overflow error detected */
> +#define FME_PR_ERR_FIFO_OVERFLOW	BIT_ULL(4)
> +
> +#define PR_WAIT_TIMEOUT   8000000
> +#define PR_HOST_STATUS_IDLE	0
> +
> +struct fme_mgr_priv {
> +	void __iomem *ioaddr;
> +	u64 pr_error;
> +};
> +
> +static u64 pr_error_to_mgr_status(u64 err)
> +{
> +	u64 status = 0;
> +
> +	if (err & FME_PR_ERR_OPERATION_ERR)
> +		status |= FPGA_MGR_STATUS_OPERATION_ERR;
> +	if (err & FME_PR_ERR_CRC_ERR)
> +		status |= FPGA_MGR_STATUS_CRC_ERR;
> +	if (err & FME_PR_ERR_INCOMPATIBLE_BS)
> +		status |= FPGA_MGR_STATUS_INCOMPATIBLE_IMAGE_ERR;
> +	if (err & FME_PR_ERR_PROTOCOL_ERR)
> +		status |= FPGA_MGR_STATUS_IP_PROTOCOL_ERR;
> +	if (err & FME_PR_ERR_FIFO_OVERFLOW)
> +		status |= FPGA_MGR_STATUS_FIFO_OVERFLOW_ERR;
> +
> +	return status;
> +}
> +
> +static u64 fme_mgr_pr_error_handle(void __iomem *fme_pr)
> +{
> +	u64 pr_status, pr_error;
> +
> +	pr_status = readq(fme_pr + FME_PR_STS);
> +	if (!(pr_status & FME_PR_STS_PR_STS))
> +		return 0;
> +
> +	pr_error = readq(fme_pr + FME_PR_ERR);
> +	writeq(pr_error, fme_pr + FME_PR_ERR);
> +
> +	return pr_error;
> +}
> +
> +static int fme_mgr_write_init(struct fpga_manager *mgr,
> +			      struct fpga_image_info *info,
> +			      const char *buf, size_t count)
> +{
> +	struct device *dev = &mgr->dev;
> +	struct fme_mgr_priv *priv = mgr->priv;
> +	void __iomem *fme_pr = priv->ioaddr;
> +	u64 pr_ctrl, pr_status;
> +
> +	if (!(info->flags & FPGA_MGR_PARTIAL_RECONFIG)) {
> +		dev_err(dev, "only supports partial reconfiguration.\n");
> +		return -EINVAL;
> +	}
> +
> +	dev_dbg(dev, "resetting PR before initiated PR\n");
> +
> +	pr_ctrl = readq(fme_pr + FME_PR_CTRL);
> +	pr_ctrl |= FME_PR_CTRL_PR_RST;
> +	writeq(pr_ctrl, fme_pr + FME_PR_CTRL);
> +
> +	if (readq_poll_timeout(fme_pr + FME_PR_CTRL, pr_ctrl,
> +			       pr_ctrl & FME_PR_CTRL_PR_RSTACK, 1,
> +			       PR_WAIT_TIMEOUT)) {
> +		dev_err(dev, "PR Reset ACK timeout\n");
> +		return -ETIMEDOUT;
> +	}
> +
> +	pr_ctrl = readq(fme_pr + FME_PR_CTRL);
> +	pr_ctrl &= ~FME_PR_CTRL_PR_RST;
> +	writeq(pr_ctrl, fme_pr + FME_PR_CTRL);
> +
> +	dev_dbg(dev,
> +		"waiting for PR resource in HW to be initialized and ready\n");
> +
> +	if (readq_poll_timeout(fme_pr + FME_PR_STS, pr_status,
> +			       (pr_status & FME_PR_STS_PR_STS) ==
> +			       FME_PR_STS_PR_STS_IDLE, 1, PR_WAIT_TIMEOUT)) {
> +		dev_err(dev, "PR Status timeout\n");
> +		priv->pr_error = fme_mgr_pr_error_handle(fme_pr);
> +		return -ETIMEDOUT;
> +	}
> +
> +	dev_dbg(dev, "check and clear previous PR error\n");
> +	priv->pr_error = fme_mgr_pr_error_handle(fme_pr);
> +	if (priv->pr_error)
> +		dev_dbg(dev, "previous PR error detected %llx\n",
> +			(unsigned long long)priv->pr_error);
> +
> +	dev_dbg(dev, "set PR port ID\n");
> +
> +	pr_ctrl = readq(fme_pr + FME_PR_CTRL);
> +	pr_ctrl &= ~FME_PR_CTRL_PR_RGN_ID;
> +	pr_ctrl |= FIELD_PREP(FME_PR_CTRL_PR_RGN_ID, info->region_id);
> +	writeq(pr_ctrl, fme_pr + FME_PR_CTRL);
> +
> +	return 0;
> +}
> +
> +static int fme_mgr_write(struct fpga_manager *mgr,
> +			 const char *buf, size_t count)
> +{
> +	struct device *dev = &mgr->dev;
> +	struct fme_mgr_priv *priv = mgr->priv;
> +	void __iomem *fme_pr = priv->ioaddr;
> +	u64 pr_ctrl, pr_status, pr_data;
> +	int delay = 0, pr_credit, i = 0;
> +
> +	dev_dbg(dev, "start request\n");
> +
> +	pr_ctrl = readq(fme_pr + FME_PR_CTRL);
> +	pr_ctrl |= FME_PR_CTRL_PR_START;
> +	writeq(pr_ctrl, fme_pr + FME_PR_CTRL);
> +
> +	dev_dbg(dev, "pushing data from bitstream to HW\n");
> +
> +	/*
> +	 * driver can push data to PR hardware using PR_DATA register once HW
> +	 * has enough pr_credit (> 1), pr_credit reduces one for every 32bit
> +	 * pr data write to PR_DATA register. If pr_credit <= 1, driver needs
> +	 * to wait for enough pr_credit from hardware by polling.
> +	 */
> +	pr_status = readq(fme_pr + FME_PR_STS);
> +	pr_credit = FIELD_GET(FME_PR_STS_PR_CREDIT, pr_status);
> +
> +	while (count > 0) {
> +		while (pr_credit <= 1) {
> +			if (delay++ > PR_WAIT_TIMEOUT) {
> +				dev_err(dev, "PR_CREDIT timeout\n");
> +				return -ETIMEDOUT;
> +			}
> +			udelay(1);
> +
> +			pr_status = readq(fme_pr + FME_PR_STS);
> +			pr_credit = FIELD_GET(FME_PR_STS_PR_CREDIT, pr_status);
> +		}
> +
> +		if (count < 4) {
> +			WARN_ON(1);
Maybe an error message instead of WARN_ON()? How about "Invalid PR
bitstream size" ?
> +			return -EINVAL;
> +		}
> +
> +		pr_data = 0;
> +		pr_data |= FIELD_PREP(FME_PR_DATA_PR_DATA_RAW,
> +				      *(((u32 *)buf) + i));
> +		writeq(pr_data, fme_pr + FME_PR_DATA);
> +		count -= 4;
> +		pr_credit--;
> +		i++;
> +	}
> +
> +	return 0;
> +}
> +
> +static int fme_mgr_write_complete(struct fpga_manager *mgr,
> +				  struct fpga_image_info *info)
> +{
> +	struct device *dev = &mgr->dev;
> +	struct fme_mgr_priv *priv = mgr->priv;
> +	void __iomem *fme_pr = priv->ioaddr;
> +	u64 pr_ctrl;
> +
> +	pr_ctrl = readq(fme_pr + FME_PR_CTRL);
> +	pr_ctrl |= FME_PR_CTRL_PR_COMPLETE;
> +	writeq(pr_ctrl, fme_pr + FME_PR_CTRL);
> +
> +	dev_dbg(dev, "green bitstream push complete\n");
> +	dev_dbg(dev, "waiting for HW to release PR resource\n");
> +
> +	if (readq_poll_timeout(fme_pr + FME_PR_CTRL, pr_ctrl,
> +			       !(pr_ctrl & FME_PR_CTRL_PR_START), 1,
> +			       PR_WAIT_TIMEOUT)) {
> +		dev_err(dev, "PR Completion ACK timeout.\n");
> +		return -ETIMEDOUT;
> +	}
> +
> +	dev_dbg(dev, "PR operation complete, checking status\n");
> +	priv->pr_error = fme_mgr_pr_error_handle(fme_pr);
> +	if (priv->pr_error) {
> +		dev_dbg(dev, "PR error detected %llx\n",
> +			(unsigned long long)priv->pr_error);
> +		return -EIO;
> +	}
> +
> +	dev_dbg(dev, "PR done successfully\n");
> +
> +	return 0;
> +}
> +
> +static enum fpga_mgr_states fme_mgr_state(struct fpga_manager *mgr)
> +{
> +	return FPGA_MGR_STATE_UNKNOWN;
> +}
> +
> +static u64 fme_mgr_status(struct fpga_manager *mgr)
> +{
> +	struct fme_mgr_priv *priv = mgr->priv;
> +
> +	return pr_error_to_mgr_status(priv->pr_error);
> +}
> +
> +static const struct fpga_manager_ops fme_mgr_ops = {
> +	.write_init = fme_mgr_write_init,
> +	.write = fme_mgr_write,
> +	.write_complete = fme_mgr_write_complete,
> +	.state = fme_mgr_state,
> +	.status = fme_mgr_status,
> +};
> +
> +static int fme_mgr_probe(struct platform_device *pdev)
> +{
> +	struct dfl_fme_mgr_pdata *pdata = dev_get_platdata(&pdev->dev);
> +	struct device *dev = &pdev->dev;
> +	struct fme_mgr_priv *priv;
> +	struct fpga_manager *mgr;
> +	struct resource *res;
> +	int ret;
> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	if (pdata->ioaddr)
> +		priv->ioaddr = pdata->ioaddr;
> +
> +	if (!priv->ioaddr) {
> +		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +		priv->ioaddr = devm_ioremap_resource(dev, res);
> +		if (IS_ERR(priv->ioaddr))
> +			return PTR_ERR(priv->ioaddr);
> +	}
> +
> +	mgr = fpga_mgr_create(dev, "DFL FME FPGA Manager",
> +			      &fme_mgr_ops, priv);
> +	if (!mgr)
> +		return -ENOMEM;
> +
> +	platform_set_drvdata(pdev, mgr);
> +
> +	ret = fpga_mgr_register(mgr);
> +	if (ret)
> +		fpga_mgr_free(mgr);
> +
> +	return ret;
> +}
> +
> +static int fme_mgr_remove(struct platform_device *pdev)
> +{
> +	struct fpga_manager *mgr = platform_get_drvdata(pdev);
> +
> +	fpga_mgr_unregister(mgr);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver fme_mgr_driver = {
> +	.driver	= {
> +		.name    = DFL_FPGA_FME_MGR,
> +	},
> +	.probe   = fme_mgr_probe,
> +	.remove  = fme_mgr_remove,
> +};
> +
> +module_platform_driver(fme_mgr_driver);
> +
> +MODULE_DESCRIPTION("FPGA Manager for DFL FPGA Management Engine");
> +MODULE_AUTHOR("Intel Corporation");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform:dfl-fme-mgr");
> -- 
> 1.8.3.1
> 

Thanks,

Moritz