Re: [PATCH V5 XRT Alveo 15/20] fpga: xrt: devctl xrt driver

Tom Rix
2021-05-04T14:07:27Z

On 4/27/21 1:54 PM, Lizhi Hou wrote:
> Add devctl driver. devctl is a type of hardware function which only has
> few registers to read or write. They are discovered by walking firmware
> metadata. A xrt device node will be created for them.
>
> Signed-off-by: Sonal Santan <sonal.santan@xilinx.com>
> Signed-off-by: Max Zhen <max.zhen@xilinx.com>
> Signed-off-by: Lizhi Hou <lizhi.hou@xilinx.com>

v4 was also ok, please add my Reviwed-by line

Reviewed-by: Tom Rix <trix@redhat.com>

> ---
> drivers/fpga/xrt/include/xleaf/devctl.h | 40 ++++++
> drivers/fpga/xrt/lib/xleaf/devctl.c | 169 ++++++++++++++++++++++++
> 2 files changed, 209 insertions(+)
> create mode 100644 drivers/fpga/xrt/include/xleaf/devctl.h
> create mode 100644 drivers/fpga/xrt/lib/xleaf/devctl.c
>
> diff --git a/drivers/fpga/xrt/include/xleaf/devctl.h b/drivers/fpga/xrt/include/xleaf/devctl.h
> new file mode 100644
> index 000000000000..b97f3b6d9326
> --- /dev/null
> +++ b/drivers/fpga/xrt/include/xleaf/devctl.h
> @@ -0,0 +1,40 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2020-2021 Xilinx, Inc.
> + *
> + * Authors:
> + * Lizhi Hou <Lizhi.Hou@xilinx.com>
> + */
> +
> +#ifndef _XRT_DEVCTL_H_
> +#define _XRT_DEVCTL_H_
> +
> +#include "xleaf.h"
> +
> +/*
> + * DEVCTL driver leaf calls.
> + */
> +enum xrt_devctl_leaf_cmd {
> + XRT_DEVCTL_READ = XRT_XLEAF_CUSTOM_BASE, /* See comments in xleaf.h */
> +};
> +
> +enum xrt_devctl_id {
> + XRT_DEVCTL_ROM_UUID = 0,
> + XRT_DEVCTL_DDR_CALIB,
> + XRT_DEVCTL_GOLDEN_VER,
> + XRT_DEVCTL_MAX
> +};
> +
> +struct xrt_devctl_rw {
> + u32 xdr_id;
> + void *xdr_buf;
> + u32 xdr_len;
> + u32 xdr_offset;
> +};
> +
> +struct xrt_devctl_intf_uuid {
> + u32 uuid_num;
> + uuid_t *uuids;
> +};
> +
> +#endif /* _XRT_DEVCTL_H_ */
> diff --git a/drivers/fpga/xrt/lib/xleaf/devctl.c b/drivers/fpga/xrt/lib/xleaf/devctl.c
> new file mode 100644
> index 000000000000..fb2122be7e56
> --- /dev/null
> +++ b/drivers/fpga/xrt/lib/xleaf/devctl.c
> @@ -0,0 +1,169 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Xilinx Alveo FPGA devctl Driver
> + *
> + * Copyright (C) 2020-2021 Xilinx, Inc.
> + *
> + * Authors:
> + * Lizhi Hou<Lizhi.Hou@xilinx.com>
> + */
> +
> +#include <linux/mod_devicetable.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/regmap.h>
> +#include <linux/io.h>
> +#include "metadata.h"
> +#include "xleaf.h"
> +#include "xleaf/devctl.h"
> +
> +#define XRT_DEVCTL "xrt_devctl"
> +
> +struct xrt_name_id {
> + char *ep_name;
> + int id;
> +};
> +
> +static struct xrt_name_id name_id[XRT_DEVCTL_MAX] = {
> + { XRT_MD_NODE_BLP_ROM, XRT_DEVCTL_ROM_UUID },
> + { XRT_MD_NODE_GOLDEN_VER, XRT_DEVCTL_GOLDEN_VER },
> +};
> +
> +XRT_DEFINE_REGMAP_CONFIG(devctl_regmap_config);
> +
> +struct xrt_devctl {
> + struct xrt_device *xdev;
> + struct regmap *regmap[XRT_DEVCTL_MAX];
> + ulong sizes[XRT_DEVCTL_MAX];
> +};
> +
> +static int xrt_devctl_name2id(struct xrt_devctl *devctl, const char *name)
> +{
> + int i;
> +
> + for (i = 0; i < XRT_DEVCTL_MAX && name_id[i].ep_name; i++) {
> + if (!strncmp(name_id[i].ep_name, name, strlen(name_id[i].ep_name) + 1))
> + return name_id[i].id;
> + }
> +
> + return -EINVAL;
> +}
> +
> +static int
> +xrt_devctl_leaf_call(struct xrt_device *xdev, u32 cmd, void *arg)
> +{
> + struct xrt_devctl *devctl;
> + int ret = 0;
> +
> + devctl = xrt_get_drvdata(xdev);
> +
> + switch (cmd) {
> + case XRT_XLEAF_EVENT:
> + /* Does not handle any event. */
> + break;
> + case XRT_DEVCTL_READ: {
> + struct xrt_devctl_rw *rw_arg = arg;
> +
> + if (rw_arg->xdr_len & 0x3) {
> + xrt_err(xdev, "invalid len %d", rw_arg->xdr_len);
> + return -EINVAL;
> + }
> +
> + if (rw_arg->xdr_id >= XRT_DEVCTL_MAX) {
> + xrt_err(xdev, "invalid id %d", rw_arg->xdr_id);
> + return -EINVAL;
> + }
> +
> + if (!devctl->regmap[rw_arg->xdr_id]) {
> + xrt_err(xdev, "io not found, id %d",
> + rw_arg->xdr_id);
> + return -EINVAL;
> + }
> +
> + ret = regmap_bulk_read(devctl->regmap[rw_arg->xdr_id], rw_arg->xdr_offset,
> + rw_arg->xdr_buf,
> + rw_arg->xdr_len / devctl_regmap_config.reg_stride);
> + break;
> + }
> + default:
> + xrt_err(xdev, "unsupported cmd %d", cmd);
> + return -EINVAL;
> + }
> +
> + return ret;
> +}
> +
> +static int xrt_devctl_probe(struct xrt_device *xdev)
> +{
> + struct xrt_devctl *devctl = NULL;
> + void __iomem *base = NULL;
> + struct resource *res;
> + int i, id, ret = 0;
> +
> + devctl = devm_kzalloc(&xdev->dev, sizeof(*devctl), GFP_KERNEL);
> + if (!devctl)
> + return -ENOMEM;
> +
> + devctl->xdev = xdev;
> + xrt_set_drvdata(xdev, devctl);
> +
> + xrt_info(xdev, "probing...");
> + for (i = 0, res = xrt_get_resource(xdev, IORESOURCE_MEM, 0);
> + res;
> + res = xrt_get_resource(xdev, IORESOURCE_MEM, ++i)) {
> + struct regmap_config config = devctl_regmap_config;
> +
> + id = xrt_devctl_name2id(devctl, res->name);
> + if (id < 0) {
> + xrt_err(xdev, "ep %s not found", res->name);
> + continue;
> + }
> + base = devm_ioremap_resource(&xdev->dev, res);
> + if (IS_ERR(base)) {
> + ret = PTR_ERR(base);
> + break;
> + }
> + config.max_register = res->end - res->start + 1;
> + devctl->regmap[id] = devm_regmap_init_mmio(&xdev->dev, base, &config);
> + if (IS_ERR(devctl->regmap[id])) {
> + xrt_err(xdev, "map base failed %pR", res);
> + ret = PTR_ERR(devctl->regmap[id]);
> + break;
> + }
> + devctl->sizes[id] = res->end - res->start + 1;
> + }
> +
> + return ret;
> +}
> +
> +static struct xrt_dev_endpoints xrt_devctl_endpoints[] = {
> + {
> + .xse_names = (struct xrt_dev_ep_names[]) {
> + /* add name if ep is in same partition */
> + { .ep_name = XRT_MD_NODE_BLP_ROM },
> + { NULL },
> + },
> + .xse_min_ep = 1,
> + },
> + {
> + .xse_names = (struct xrt_dev_ep_names[]) {
> + { .ep_name = XRT_MD_NODE_GOLDEN_VER },
> + { NULL },
> + },
> + .xse_min_ep = 1,
> + },
> + /* adding ep bundle generates devctl device instance */
> + { 0 },
> +};
> +
> +static struct xrt_driver xrt_devctl_driver = {
> + .driver = {
> + .name = XRT_DEVCTL,
> + },
> + .subdev_id = XRT_SUBDEV_DEVCTL,
> + .endpoints = xrt_devctl_endpoints,
> + .probe = xrt_devctl_probe,
> + .leaf_call = xrt_devctl_leaf_call,
> +};
> +
> +XRT_LEAF_INIT_FINI_FUNC(devctl);