[PATCH V3 XRT Alveo 11/18] fpga: xrt: UCS platform driver

Lizhi Hou
2021-02-18T07:43:30Z

Add 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@xilinx.com>
Signed-off-by: Max Zhen <max.zhen@xilinx.com>
Signed-off-by: Lizhi Hou <lizhih@xilinx.com>
---
drivers/fpga/xrt/include/xleaf/ucs.h | 24 +++
drivers/fpga/xrt/lib/xleaf/ucs.c | 235 +++++++++++++++++++++++++++
2 files changed, 259 insertions(+)
create mode 100644 drivers/fpga/xrt/include/xleaf/ucs.h
create mode 100644 drivers/fpga/xrt/lib/xleaf/ucs.c

diff --git a/drivers/fpga/xrt/include/xleaf/ucs.h b/drivers/fpga/xrt/include/xleaf/ucs.h
new file mode 100644
index 000000000000..a5ef0e100e12
--- /dev/null
+++ b/drivers/fpga/xrt/include/xleaf/ucs.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Header file for XRT UCS Leaf Driver
+ *
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ * Lizhi Hou <Lizhi.Hou@xilinx.com>
+ */
+
+#ifndef _XRT_UCS_H_
+#define _XRT_UCS_H_
+
+#include "xleaf.h"
+
+/*
+ * UCS driver IOCTL calls.
+ */
+enum xrt_ucs_ioctl_cmd {
+ XRT_UCS_CHECK = XRT_XLEAF_CUSTOM_BASE, /* See comments in xleaf.h */
+ XRT_UCS_ENABLE,
+};
+
+#endif /* _XRT_UCS_H_ */
diff --git a/drivers/fpga/xrt/lib/xleaf/ucs.c b/drivers/fpga/xrt/lib/xleaf/ucs.c
new file mode 100644
index 000000000000..ae762c8fddbb
--- /dev/null
+++ b/drivers/fpga/xrt/lib/xleaf/ucs.c
@@ -0,0 +1,235 @@
+// 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/platform_device.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include "metadata.h"
+#include "xleaf.h"
+#include "xleaf/ucs.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 CHANNEL1_OFFSET 0
+#define CHANNEL2_OFFSET 8
+
+#define CLK_MAX_VALUE 6400
+
+struct ucs_control_status_ch1 {
+ unsigned int shutdown_clocks_latched:1;
+ unsigned int reserved1:15;
+ unsigned int clock_throttling_average:14;
+ unsigned int reserved2:2;
+};
+
+struct xrt_ucs {
+ struct platform_device *pdev;
+ void __iomem *ucs_base;
+ struct mutex ucs_lock; /* ucs dev lock */
+};
+
+static inline u32 reg_rd(struct xrt_ucs *ucs, u32 offset)
+{
+ return ioread32(ucs->ucs_base + offset);
+}
+
+static inline void reg_wr(struct xrt_ucs *ucs, u32 val, u32 offset)
+{
+ iowrite32(val, ucs->ucs_base + offset);
+}
+
+static void xrt_ucs_event_cb(struct platform_device *pdev, void *arg)
+{
+ struct platform_device *leaf;
+ struct xrt_event *evt = (struct xrt_event *)arg;
+ enum xrt_events e = evt->xe_evt;
+ enum xrt_subdev_id id = evt->xe_subdev.xevt_subdev_id;
+ int instance = evt->xe_subdev.xevt_subdev_instance;
+
+ switch (e) {
+ case XRT_EVENT_POST_CREATION:
+ break;
+ default:
+ 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_ioctl(leaf, XRT_CLOCK_VERIFY, NULL);
+ xleaf_put_leaf(pdev, leaf);
+}
+
+static void ucs_check(struct xrt_ucs *ucs, bool *latched)
+{
+ struct ucs_control_status_ch1 *ucs_status_ch1;
+ u32 status;
+
+ mutex_lock(&ucs->ucs_lock);
+ status = reg_rd(ucs, CHANNEL1_OFFSET);
+ ucs_status_ch1 = (struct ucs_control_status_ch1 *)&status;
+ if (ucs_status_ch1->shutdown_clocks_latched) {
+ UCS_ERR(ucs,
+ "Critical temperature or power event, kernel clocks have been stopped.");
+ UCS_ERR(ucs,
+ "run 'xbutil valiate -q' to continue. See AR 73398 for more details.");
+ /* explicitly indicate reset should be latched */
+ *latched = true;
+ } else if (ucs_status_ch1->clock_throttling_average >
+ CLK_MAX_VALUE) {
+ UCS_ERR(ucs, "kernel clocks %d exceeds expected maximum value %d.",
+ ucs_status_ch1->clock_throttling_average,
+ CLK_MAX_VALUE);
+ } else if (ucs_status_ch1->clock_throttling_average) {
+ UCS_ERR(ucs, "kernel clocks throttled at %d%%.",
+ (ucs_status_ch1->clock_throttling_average /
+ (CLK_MAX_VALUE / 100)));
+ }
+ mutex_unlock(&ucs->ucs_lock);
+}
+
+static void ucs_enable(struct xrt_ucs *ucs)
+{
+ reg_wr(ucs, 1, CHANNEL2_OFFSET);
+}
+
+static int
+xrt_ucs_leaf_ioctl(struct platform_device *pdev, u32 cmd, void *arg)
+{
+ struct xrt_ucs *ucs;
+ int ret = 0;
+
+ ucs = platform_get_drvdata(pdev);
+
+ switch (cmd) {
+ case XRT_XLEAF_EVENT:
+ xrt_ucs_event_cb(pdev, arg);
+ break;
+ case XRT_UCS_CHECK: {
+ ucs_check(ucs, (bool *)arg);
+ break;
+ }
+ case XRT_UCS_ENABLE:
+ ucs_enable(ucs);
+ break;
+ default:
+ xrt_err(pdev, "unsupported cmd %d", cmd);
+ return -EINVAL;
+ }
+
+ return ret;
+}
+
+static int ucs_remove(struct platform_device *pdev)
+{
+ struct xrt_ucs *ucs;
+
+ ucs = platform_get_drvdata(pdev);
+ if (!ucs) {
+ xrt_err(pdev, "driver data is NULL");
+ return -EINVAL;
+ }
+
+ if (ucs->ucs_base)
+ iounmap(ucs->ucs_base);
+
+ platform_set_drvdata(pdev, NULL);
+ devm_kfree(&pdev->dev, ucs);
+
+ return 0;
+}
+
+static int ucs_probe(struct platform_device *pdev)
+{
+ struct xrt_ucs *ucs = NULL;
+ struct resource *res;
+ int ret;
+
+ 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);
+ ucs->ucs_base = ioremap(res->start, res->end - res->start + 1);
+ if (!ucs->ucs_base) {
+ UCS_ERR(ucs, "map base %pR failed", res);
+ ret = -EFAULT;
+ goto failed;
+ }
+ ucs_enable(ucs);
+
+ return 0;
+
+failed:
+ ucs_remove(pdev);
+ return ret;
+}
+
+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_ioctl = xrt_ucs_leaf_ioctl,
+ },
+};
+
+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,
+ .remove = ucs_remove,
+ .id_table = xrt_ucs_table,
+};
+
+void ucs_leaf_init_fini(bool init)
+{
+ if (init)
+ xleaf_register_driver(XRT_SUBDEV_UCS, &xrt_ucs_driver, xrt_ucs_endpoints);
+ else
+ xleaf_unregister_driver(XRT_SUBDEV_UCS);
+}
--
2.18.4