[PATCH V4 XRT Alveo 13/20] fpga: xrt: User Clock Subsystem platform driver

From: Lizhi Hou
Date: Wed Mar 24 2021 - 01:36:43 EST


Add User Clock Subsystem (UCS) driver. UCS is a hardware function
discovered by walking xclbin metadata. A platform device node will be
created for it. UCS enables/disables the dynamic region clocks.

Signed-off-by: Sonal Santan <sonal.santan@xxxxxxxxxx>
Signed-off-by: Max Zhen <max.zhen@xxxxxxxxxx>
Signed-off-by: Lizhi Hou <lizhi.hou@xxxxxxxxxx>
---
drivers/fpga/xrt/lib/xleaf/ucs.c | 167 +++++++++++++++++++++++++++++++
1 file changed, 167 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..d91ee229e7cb
--- /dev/null
+++ b/drivers/fpga/xrt/lib/xleaf/ucs.c
@@ -0,0 +1,167 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx Alveo FPGA UCS Driver
+ *
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ * Lizhi Hou<Lizhi.Hou@xxxxxxxxxx>
+ */
+
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.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)->pdev, fmt "\n", ##arg)
+#define UCS_WARN(ucs, fmt, arg...) \
+ xrt_warn((ucs)->pdev, fmt "\n", ##arg)
+#define UCS_INFO(ucs, fmt, arg...) \
+ xrt_info((ucs)->pdev, fmt "\n", ##arg)
+#define UCS_DBG(ucs, fmt, arg...) \
+ xrt_dbg((ucs)->pdev, 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
+
+static const struct regmap_config ucs_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = 0x1000,
+};
+
+struct xrt_ucs {
+ struct platform_device *pdev;
+ struct regmap *regmap;
+ struct mutex ucs_lock; /* ucs dev lock */
+};
+
+static void xrt_ucs_event_cb(struct platform_device *pdev, void *arg)
+{
+ struct xrt_event *evt = (struct xrt_event *)arg;
+ enum xrt_events e = evt->xe_evt;
+ struct platform_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(pdev, "ignored event %d", e);
+ return;
+ }
+
+ if (id != XRT_SUBDEV_CLOCK)
+ return;
+
+ leaf = xleaf_get_leaf_by_id(pdev, XRT_SUBDEV_CLOCK, instance);
+ if (!leaf) {
+ xrt_err(pdev, "does not get clock subdev");
+ return;
+ }
+
+ xleaf_call(leaf, XRT_CLOCK_VERIFY, NULL);
+ xleaf_put_leaf(pdev, 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 platform_device *pdev, u32 cmd, void *arg)
+{
+ switch (cmd) {
+ case XRT_XLEAF_EVENT:
+ xrt_ucs_event_cb(pdev, arg);
+ break;
+ default:
+ xrt_err(pdev, "unsupported cmd %d", cmd);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int ucs_probe(struct platform_device *pdev)
+{
+ struct xrt_ucs *ucs = NULL;
+ void __iomem *base = NULL;
+ struct resource *res;
+
+ ucs = devm_kzalloc(&pdev->dev, sizeof(*ucs), GFP_KERNEL);
+ if (!ucs)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, ucs);
+ ucs->pdev = pdev;
+ mutex_init(&ucs->ucs_lock);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -EINVAL;
+
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ ucs->regmap = devm_regmap_init_mmio(&pdev->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_subdev_endpoints xrt_ucs_endpoints[] = {
+ {
+ .xse_names = (struct xrt_subdev_ep_names[]) {
+ { .ep_name = XRT_MD_NODE_UCS_CONTROL_STATUS },
+ { NULL },
+ },
+ .xse_min_ep = 1,
+ },
+ { 0 },
+};
+
+static struct xrt_subdev_drvdata xrt_ucs_data = {
+ .xsd_dev_ops = {
+ .xsd_leaf_call = xrt_ucs_leaf_call,
+ },
+};
+
+static const struct platform_device_id xrt_ucs_table[] = {
+ { XRT_UCS, (kernel_ulong_t)&xrt_ucs_data },
+ { },
+};
+
+static struct platform_driver xrt_ucs_driver = {
+ .driver = {
+ .name = XRT_UCS,
+ },
+ .probe = ucs_probe,
+ .id_table = xrt_ucs_table,
+};
+
+XRT_LEAF_INIT_FINI_FUNC(XRT_SUBDEV_UCS, ucs);
--
2.27.0