Re: [PATCH V5 XRT Alveo 13/20] fpga: xrt: User Clock Subsystem driver

Tom Rix
2021-05-04T14:04:11Z

On 4/27/21 1:54 PM, Lizhi Hou wrote:
> Add User Clock Subsystem (UCS) driver. UCS is a hardware function
> discovered by walking xclbin metadata. A xrt device node will be
> created for it. UCS enables/disables the dynamic region clocks.
>
> 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 ok, please add my Reviewed-by line here, under yours.

Do for the others I have also ok-ed.

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

> ---
> drivers/fpga/xrt/lib/xleaf/ucs.c | 152 +++++++++++++++++++++++++++++++
> 1 file changed, 152 insertions(+)
> create mode 100644 drivers/fpga/xrt/lib/xleaf/ucs.c
>
> diff --git a/drivers/fpga/xrt/lib/xleaf/ucs.c b/drivers/fpga/xrt/lib/xleaf/ucs.c
> new file mode 100644
> index 000000000000..a7a96ddde44f
> --- /dev/null
> +++ b/drivers/fpga/xrt/lib/xleaf/ucs.c
> @@ -0,0 +1,152 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Xilinx Alveo FPGA UCS 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/clock.h"
> +
> +#define UCS_ERR(ucs, fmt, arg...) \
> + xrt_err((ucs)->xdev, fmt "\n", ##arg)
> +#define UCS_WARN(ucs, fmt, arg...) \
> + xrt_warn((ucs)->xdev, fmt "\n", ##arg)
> +#define UCS_INFO(ucs, fmt, arg...) \
> + xrt_info((ucs)->xdev, fmt "\n", ##arg)
> +#define UCS_DBG(ucs, fmt, arg...) \
> + xrt_dbg((ucs)->xdev, fmt "\n", ##arg)
> +
> +#define XRT_UCS "xrt_ucs"
> +
> +#define XRT_UCS_CHANNEL1_REG 0
> +#define XRT_UCS_CHANNEL2_REG 8
> +
> +#define CLK_MAX_VALUE 6400
> +
> +XRT_DEFINE_REGMAP_CONFIG(ucs_regmap_config);
> +
> +struct xrt_ucs {
> + struct xrt_device *xdev;
> + struct regmap *regmap;
> + struct mutex ucs_lock; /* ucs dev lock */
> +};
> +
> +static void xrt_ucs_event_cb(struct xrt_device *xdev, void *arg)
> +{
> + struct xrt_event *evt = (struct xrt_event *)arg;
> + enum xrt_events e = evt->xe_evt;
> + struct xrt_device *leaf;
> + enum xrt_subdev_id id;
> + int instance;
> +
> + id = evt->xe_subdev.xevt_subdev_id;
> + instance = evt->xe_subdev.xevt_subdev_instance;
> +
> + if (e != XRT_EVENT_POST_CREATION) {
> + xrt_dbg(xdev, "ignored event %d", e);
> + return;
> + }
> +
> + if (id != XRT_SUBDEV_CLOCK)
> + return;
> +
> + leaf = xleaf_get_leaf_by_id(xdev, XRT_SUBDEV_CLOCK, instance);
> + if (!leaf) {
> + xrt_err(xdev, "does not get clock subdev");
> + return;
> + }
> +
> + xleaf_call(leaf, XRT_CLOCK_VERIFY, NULL);
> + xleaf_put_leaf(xdev, leaf);
> +}
> +
> +static int ucs_enable(struct xrt_ucs *ucs)
> +{
> + int ret;
> +
> + mutex_lock(&ucs->ucs_lock);
> + ret = regmap_write(ucs->regmap, XRT_UCS_CHANNEL2_REG, 1);
> + mutex_unlock(&ucs->ucs_lock);
> +
> + return ret;
> +}
> +
> +static int
> +xrt_ucs_leaf_call(struct xrt_device *xdev, u32 cmd, void *arg)
> +{
> + switch (cmd) {
> + case XRT_XLEAF_EVENT:
> + xrt_ucs_event_cb(xdev, arg);
> + break;
> + default:
> + xrt_err(xdev, "unsupported cmd %d", cmd);
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static int ucs_probe(struct xrt_device *xdev)
> +{
> + struct xrt_ucs *ucs = NULL;
> + void __iomem *base = NULL;
> + struct resource *res;
> +
> + ucs = devm_kzalloc(&xdev->dev, sizeof(*ucs), GFP_KERNEL);
> + if (!ucs)
> + return -ENOMEM;
> +
> + xrt_set_drvdata(xdev, ucs);
> + ucs->xdev = xdev;
> + mutex_init(&ucs->ucs_lock);
> +
> + res = xrt_get_resource(xdev, IORESOURCE_MEM, 0);
> + if (!res)
> + return -EINVAL;
> +
> + base = devm_ioremap_resource(&xdev->dev, res);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + ucs->regmap = devm_regmap_init_mmio(&xdev->dev, base, &ucs_regmap_config);
> + if (IS_ERR(ucs->regmap)) {
> + UCS_ERR(ucs, "map base %pR failed", res);
> + return PTR_ERR(ucs->regmap);
> + }
> + ucs_enable(ucs);
> +
> + return 0;
> +}
> +
> +static struct xrt_dev_endpoints xrt_ucs_endpoints[] = {
> + {
> + .xse_names = (struct xrt_dev_ep_names[]) {
> + { .ep_name = XRT_MD_NODE_UCS_CONTROL_STATUS },
> + { NULL },
> + },
> + .xse_min_ep = 1,
> + },
> + { 0 },
> +};
> +
> +static struct xrt_driver xrt_ucs_driver = {
> + .driver = {
> + .name = XRT_UCS,
> + },
> + .subdev_id = XRT_SUBDEV_UCS,
> + .endpoints = xrt_ucs_endpoints,
> + .probe = ucs_probe,
> + .leaf_call = xrt_ucs_leaf_call,
> +};
> +
> +XRT_LEAF_INIT_FINI_FUNC(ucs);