Merge tag 'fpga-dfl-for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mdf/linux-fpga into char-misc-next

Moritz writes:

FPGA DFL Changes for 5.4

This pull-request contains the FPGA DFL changes for 5.4

- The first three patches are cleanup patches making use of dev_groups and
making the init callback optional.
- One patch adds userclock sysfs entries that are DFL specific
- One patch exposes AFU port disable/enable functions
- One patch adds error reporting
- One patch adds AFU SignalTap support
- One patch adds FME global error reporting
- The final patch is a documentation patch that decribes the
virtualization interfaces

This patchset requires the 'dev_groups_all_drivers' tag from drivers
core for the dev_groups refactoring as well as the DFL changes already
in char-misc-next.

Signed-off-by: Moritz Fischer <[e-mail]>

* tag 'fpga-dfl-for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mdf/linux-fpga:
Documentation: fpga: dfl: add descriptions for virtualization and new interfaces.
fpga: dfl: fme: add global error reporting support
fpga: dfl: afu: add STP (SignalTap) support
fpga: dfl: afu: add error reporting support.
fpga: dfl: afu: expose __afu_port_enable/disable function.
fpga: dfl: afu: add userclock sysfs interfaces.
fpga: dfl: afu: convert platform_driver to use dev_groups
fpga: dfl: fme: convert platform_driver to use dev_groups
fpga: dfl: make init callback optional
driver core: add dev_groups to all drivers

Documentation/ABI/testing/sysfs-platform-dfl-fme

···
 		this FPGA belongs to, only valid for integrated solution.
 		User only needs this information, in case standard numa node
 		can't provide correct information.
+
+What:		/sys/bus/platform/devices/dfl-fme.0/errors/pcie0_errors
+Date:		August 2019
+KernelVersion:  5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-Write. Read this file for errors detected on pcie0 link.
+		Write this file to clear errors logged in pcie0_errors. Write
+		fails with -EINVAL if input parsing fails or input error code
+		doesn't match.
+
+What:		/sys/bus/platform/devices/dfl-fme.0/errors/pcie1_errors
+Date:		August 2019
+KernelVersion:  5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-Write. Read this file for errors detected on pcie1 link.
+		Write this file to clear errors logged in pcie1_errors. Write
+		fails with -EINVAL if input parsing fails or input error code
+		doesn't match.
+
+What:		/sys/bus/platform/devices/dfl-fme.0/errors/nonfatal_errors
+Date:		August 2019
+KernelVersion:  5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-only. It returns non-fatal errors detected.
+
+What:		/sys/bus/platform/devices/dfl-fme.0/errors/catfatal_errors
+Date:		August 2019
+KernelVersion:  5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-only. It returns catastrophic and fatal errors detected.
+
+What:		/sys/bus/platform/devices/dfl-fme.0/errors/inject_errors
+Date:		August 2019
+KernelVersion:  5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-Write. Read this file to check errors injected. Write this
+		file to inject errors for testing purpose. Write fails with
+		-EINVAL if input parsing fails or input inject error code isn't
+		supported.
+
+What:		/sys/bus/platform/devices/dfl-fme.0/errors/fme_errors
+Date:		August 2019
+KernelVersion:  5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-Write. Read this file to get errors detected on FME.
+		Write this file to clear errors logged in fme_errors. Write
+		fials with -EINVAL if input parsing fails or input error code
+		doesn't match.
+
+What:		/sys/bus/platform/devices/dfl-fme.0/errors/first_error
+Date:		August 2019
+KernelVersion:  5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-only. Read this file to get the first error detected by
+		hardware.
+
+What:		/sys/bus/platform/devices/dfl-fme.0/errors/next_error
+Date:		August 2019
+KernelVersion:  5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-only. Read this file to get the second error detected by
+		hardware.

Documentation/ABI/testing/sysfs-platform-dfl-port

···
 Description:	Read-write. Read or set AFU latency tolerance reporting value.
 		Set ltr to 1 if the AFU can tolerate latency >= 40us or set it
 		to 0 if it is latency sensitive.
+
+What:		/sys/bus/platform/devices/dfl-port.0/userclk_freqcmd
+Date:		August 2019
+KernelVersion:	5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Write-only. User writes command to this interface to set
+		userclock to AFU.
+
+What:		/sys/bus/platform/devices/dfl-port.0/userclk_freqsts
+Date:		August 2019
+KernelVersion:	5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-only. Read this file to get the status of issued command
+		to userclck_freqcmd.
+
+What:		/sys/bus/platform/devices/dfl-port.0/userclk_freqcntrcmd
+Date:		August 2019
+KernelVersion:	5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Write-only. User writes command to this interface to set
+		userclock counter.
+
+What:		/sys/bus/platform/devices/dfl-port.0/userclk_freqcntrsts
+Date:		August 2019
+KernelVersion:	5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-only. Read this file to get the status of issued command
+		to userclck_freqcntrcmd.
+
+What:		/sys/bus/platform/devices/dfl-port.0/errors/errors
+Date:		August 2019
+KernelVersion:	5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-Write. Read this file to get errors detected on port and
+		Accelerated Function Unit (AFU). Write error code to this file
+		to clear errors. Write fails with -EINVAL if input parsing
+		fails or input error code doesn't match. Write fails with
+		-EBUSY or -ETIMEDOUT if error can't be cleared as hardware
+		in low power state (-EBUSY) or not respoding (-ETIMEDOUT).
+
+What:		/sys/bus/platform/devices/dfl-port.0/errors/first_error
+Date:		August 2019
+KernelVersion:	5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-only. Read this file to get the first error detected by
+		hardware.
+
+What:		/sys/bus/platform/devices/dfl-port.0/errors/first_malformed_req
+Date:		August 2019
+KernelVersion:	5.4
+Contact:	Wu Hao <[e-mail]>
+Description:	Read-only. Read this file to get the first malformed request
+		captured by hardware.

Documentation/fpga/dfl.rst

···
 - Get driver API version (DFL_FPGA_GET_API_VERSION)
 - Check for extensions (DFL_FPGA_CHECK_EXTENSION)
 - Program bitstream (DFL_FPGA_FME_PORT_PR)
+- Assign port to PF (DFL_FPGA_FME_PORT_ASSIGN)
+- Release port from PF (DFL_FPGA_FME_PORT_RELEASE)
 
 More functions are exposed through sysfs
 (/sys/class/fpga_region/regionX/dfl-fme.n/):
···
  Read number of ports (ports_num)
      one FPGA device may have more than one port, this sysfs interface indicates
      how many ports the FPGA device has.
+
+ Global error reporting management (errors/)
+     error reporting sysfs interfaces allow user to read errors detected by the
+     hardware, and clear the logged errors.
 
 
 FIU - PORT
···
 
  Read Accelerator GUID (afu_id)
      afu_id indicates which PR bitstream is programmed to this AFU.
+
+ Error reporting (errors/)
+     error reporting sysfs interfaces allow user to read port/afu errors
+     detected by the hardware, and clear the logged errors.
 
 
 DFL Framework Overview
···
 the compat_id exposed by the target FPGA region. This check is usually done by
 userspace before calling the reconfiguration IOCTL.
 
+
+FPGA virtualization - PCIe SRIOV
+================================
+This section describes the virtualization support on DFL based FPGA device to
+enable accessing an accelerator from applications running in a virtual machine
+(VM). This section only describes the PCIe based FPGA device with SRIOV support.
+
+Features supported by the particular FPGA device are exposed through Device
+Feature Lists, as illustrated below:
+
+::
+
+    +-------------------------------+  +-------------+
+    |              PF               |  |     VF      |
+    +-------------------------------+  +-------------+
+        ^            ^         ^              ^
+        |            |         |              |
+  +-----|------------|---------|--------------|-------+
+  |     |            |         |              |       |
+  |  +-----+     +-------+ +-------+      +-------+   |
+  |  | FME |     | Port0 | | Port1 |      | Port2 |   |
+  |  +-----+     +-------+ +-------+      +-------+   |
+  |                  ^         ^              ^       |
+  |                  |         |              |       |
+  |              +-------+ +------+       +-------+   |
+  |              |  AFU  | |  AFU |       |  AFU  |   |
+  |              +-------+ +------+       +-------+   |
+  |                                                   |
+  |            DFL based FPGA PCIe Device             |
+  +---------------------------------------------------+
+
+FME is always accessed through the physical function (PF).
+
+Ports (and related AFUs) are accessed via PF by default, but could be exposed
+through virtual function (VF) devices via PCIe SRIOV. Each VF only contains
+1 Port and 1 AFU for isolation. Users could assign individual VFs (accelerators)
+created via PCIe SRIOV interface, to virtual machines.
+
+The driver organization in virtualization case is illustrated below:
+::
+
+    +-------++------++------+             |
+    | FME   || FME  || FME  |             |
+    | FPGA  || FPGA || FPGA |             |
+    |Manager||Bridge||Region|             |
+    +-------++------++------+             |
+    +-----------------------+  +--------+ |             +--------+
+    |          FME          |  |  AFU   | |             |  AFU   |
+    |         Module        |  | Module | |             | Module |
+    +-----------------------+  +--------+ |             +--------+
+          +-----------------------+       |       +-----------------------+
+          | FPGA Container Device |       |       | FPGA Container Device |
+          |  (FPGA Base Region)   |       |       |  (FPGA Base Region)   |
+          +-----------------------+       |       +-----------------------+
+            +------------------+          |         +------------------+
+            | FPGA PCIE Module |          | Virtual | FPGA PCIE Module |
+            +------------------+   Host   | Machine +------------------+
+   -------------------------------------- | ------------------------------
+             +---------------+            |          +---------------+
+             | PCI PF Device |            |          | PCI VF Device |
+             +---------------+            |          +---------------+
+
+FPGA PCIe device driver is always loaded first once a FPGA PCIe PF or VF device
+is detected. It:
+
+* Finishes enumeration on both FPGA PCIe PF and VF device using common
+  interfaces from DFL framework.
+* Supports SRIOV.
+
+The FME device driver plays a management role in this driver architecture, it
+provides ioctls to release Port from PF and assign Port to PF. After release
+a port from PF, then it's safe to expose this port through a VF via PCIe SRIOV
+sysfs interface.
+
+To enable accessing an accelerator from applications running in a VM, the
+respective AFU's port needs to be assigned to a VF using the following steps:
+
+#. The PF owns all AFU ports by default. Any port that needs to be
+   reassigned to a VF must first be released through the
+   DFL_FPGA_FME_PORT_RELEASE ioctl on the FME device.
+
+#. Once N ports are released from PF, then user can use command below
+   to enable SRIOV and VFs. Each VF owns only one Port with AFU.
+
+   ::
+
+      echo N > $PCI_DEVICE_PATH/sriov_numvfs
+
+#. Pass through the VFs to VMs
+
+#. The AFU under VF is accessible from applications in VM (using the
+   same driver inside the VF).
+
+Note that an FME can't be assigned to a VF, thus PR and other management
+functions are only available via the PF.
 
 Device enumeration
 ==================

drivers/base/dd.c

···
 			goto probe_failed;
 	}
 
+	if (device_add_groups(dev, drv->dev_groups)) {
+		dev_err(dev, "device_add_groups() failed\n");
+		goto dev_groups_failed;
+	}
+
 	if (test_remove) {
 		test_remove = false;
+
+		device_remove_groups(dev, drv->dev_groups);
 
 		if (dev->bus->remove)
 			dev->bus->remove(dev);
···
 		 drv->bus->name, __func__, dev_name(dev), drv->name);
 	goto done;
 
+dev_groups_failed:
+	if (dev->bus->remove)
+		dev->bus->remove(dev);
+	else if (drv->remove)
+		drv->remove(dev);
 probe_failed:
 	if (dev->bus)
 		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
···
 						     dev);
 
 		pm_runtime_put_sync(dev);
+
+		device_remove_groups(dev, drv->dev_groups);
 
 		if (dev->bus && dev->bus->remove)
 			dev->bus->remove(dev);

drivers/fpga/Makefile

···
 obj-$(CONFIG_FPGA_DFL_FME_REGION)	+= dfl-fme-region.o
 obj-$(CONFIG_FPGA_DFL_AFU)		+= dfl-afu.o
 
-dfl-fme-objs := dfl-fme-main.o dfl-fme-pr.o
+dfl-fme-objs := dfl-fme-main.o dfl-fme-pr.o dfl-fme-error.o
 dfl-afu-objs := dfl-afu-main.o dfl-afu-region.o dfl-afu-dma-region.o
+dfl-afu-objs += dfl-afu-error.o
 
 # Drivers for FPGAs which implement DFL
 obj-$(CONFIG_FPGA_DFL_PCI)		+= dfl-pci.o

drivers/fpga/dfl-afu-error.c

···
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for FPGA Accelerated Function Unit (AFU) Error Reporting
+ *
+ * Copyright 2019 Intel Corporation, Inc.
+ *
+ * Authors:
+ *   Wu Hao <[e-mail]>
+ *   Xiao Guangrong <[e-mail]>
+ *   Joseph Grecco <[e-mail]>
+ *   Enno Luebbers <[e-mail]>
+ *   Tim Whisonant <[e-mail]>
+ *   Ananda Ravuri <[e-mail]>
+ *   Mitchel Henry <[e-mail]>
+ */
+
+#include <linux/uaccess.h>
+
+#include "dfl-afu.h"
+
+#define PORT_ERROR_MASK		0x8
+#define PORT_ERROR		0x10
+#define PORT_FIRST_ERROR	0x18
+#define PORT_MALFORMED_REQ0	0x20
+#define PORT_MALFORMED_REQ1	0x28
+
+#define ERROR_MASK		GENMASK_ULL(63, 0)
+
+/* mask or unmask port errors by the error mask register. */
+static void __afu_port_err_mask(struct device *dev, bool mask)
+{
+	void __iomem *base;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_ERROR);
+
+	writeq(mask ? ERROR_MASK : 0, base + PORT_ERROR_MASK);
+}
+
+static void afu_port_err_mask(struct device *dev, bool mask)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+
+	mutex_lock(&pdata->lock);
+	__afu_port_err_mask(dev, mask);
+	mutex_unlock(&pdata->lock);
+}
+
+/* clear port errors. */
+static int afu_port_err_clear(struct device *dev, u64 err)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	struct platform_device *pdev = to_platform_device(dev);
+	void __iomem *base_err, *base_hdr;
+	int ret = -EBUSY;
+	u64 v;
+
+	base_err = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_ERROR);
+	base_hdr = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_HEADER);
+
+	mutex_lock(&pdata->lock);
+
+	/*
+	 * clear Port Errors
+	 *
+	 * - Check for AP6 State
+	 * - Halt Port by keeping Port in reset
+	 * - Set PORT Error mask to all 1 to mask errors
+	 * - Clear all errors
+	 * - Set Port mask to all 0 to enable errors
+	 * - All errors start capturing new errors
+	 * - Enable Port by pulling the port out of reset
+	 */
+
+	/* if device is still in AP6 power state, can not clear any error. */
+	v = readq(base_hdr + PORT_HDR_STS);
+	if (FIELD_GET(PORT_STS_PWR_STATE, v) == PORT_STS_PWR_STATE_AP6) {
+		dev_err(dev, "Could not clear errors, device in AP6 state.\n");
+		goto done;
+	}
+
+	/* Halt Port by keeping Port in reset */
+	ret = __afu_port_disable(pdev);
+	if (ret)
+		goto done;
+
+	/* Mask all errors */
+	__afu_port_err_mask(dev, true);
+
+	/* Clear errors if err input matches with current port errors.*/
+	v = readq(base_err + PORT_ERROR);
+
+	if (v == err) {
+		writeq(v, base_err + PORT_ERROR);
+
+		v = readq(base_err + PORT_FIRST_ERROR);
+		writeq(v, base_err + PORT_FIRST_ERROR);
+	} else {
+		ret = -EINVAL;
+	}
+
+	/* Clear mask */
+	__afu_port_err_mask(dev, false);
+
+	/* Enable the Port by clear the reset */
+	__afu_port_enable(pdev);
+
+done:
+	mutex_unlock(&pdata->lock);
+	return ret;
+}
+
+static ssize_t errors_show(struct device *dev, struct device_attribute *attr,
+			   char *buf)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	u64 error;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_ERROR);
+
+	mutex_lock(&pdata->lock);
+	error = readq(base + PORT_ERROR);
+	mutex_unlock(&pdata->lock);
+
+	return sprintf(buf, "0x%llx\n", (unsigned long long)error);
+}
+
+static ssize_t errors_store(struct device *dev, struct device_attribute *attr,
+			    const char *buff, size_t count)
+{
+	u64 value;
+	int ret;
+
+	if (kstrtou64(buff, 0, &value))
+		return -EINVAL;
+
+	ret = afu_port_err_clear(dev, value);
+
+	return ret ? ret : count;
+}
+static DEVICE_ATTR_RW(errors);
+
+static ssize_t first_error_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	u64 error;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_ERROR);
+
+	mutex_lock(&pdata->lock);
+	error = readq(base + PORT_FIRST_ERROR);
+	mutex_unlock(&pdata->lock);
+
+	return sprintf(buf, "0x%llx\n", (unsigned long long)error);
+}
+static DEVICE_ATTR_RO(first_error);
+
+static ssize_t first_malformed_req_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	u64 req0, req1;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_ERROR);
+
+	mutex_lock(&pdata->lock);
+	req0 = readq(base + PORT_MALFORMED_REQ0);
+	req1 = readq(base + PORT_MALFORMED_REQ1);
+	mutex_unlock(&pdata->lock);
+
+	return sprintf(buf, "0x%016llx%016llx\n",
+		       (unsigned long long)req1, (unsigned long long)req0);
+}
+static DEVICE_ATTR_RO(first_malformed_req);
+
+static struct attribute *port_err_attrs[] = {
+	&dev_attr_errors.attr,
+	&dev_attr_first_error.attr,
+	&dev_attr_first_malformed_req.attr,
+	NULL,
+};
+
+static umode_t port_err_attrs_visible(struct kobject *kobj,
+				      struct attribute *attr, int n)
+{
+	struct device *dev = kobj_to_dev(kobj);
+
+	/*
+	 * sysfs entries are visible only if related private feature is
+	 * enumerated.
+	 */
+	if (!dfl_get_feature_by_id(dev, PORT_FEATURE_ID_ERROR))
+		return 0;
+
+	return attr->mode;
+}
+
+const struct attribute_group port_err_group = {
+	.name       = "errors",
+	.attrs      = port_err_attrs,
+	.is_visible = port_err_attrs_visible,
+};
+
+static int port_err_init(struct platform_device *pdev,
+			 struct dfl_feature *feature)
+{
+	afu_port_err_mask(&pdev->dev, false);
+
+	return 0;
+}
+
+static void port_err_uinit(struct platform_device *pdev,
+			   struct dfl_feature *feature)
+{
+	afu_port_err_mask(&pdev->dev, true);
+}
+
+const struct dfl_feature_id port_err_id_table[] = {
+	{.id = PORT_FEATURE_ID_ERROR,},
+	{0,}
+};
+
+const struct dfl_feature_ops port_err_ops = {
+	.init = port_err_init,
+	.uinit = port_err_uinit,
+};

drivers/fpga/dfl-afu-main.c

···
 #include "dfl-afu.h"
 
 /**
- * port_enable - enable a port
+ * __afu_port_enable - enable a port by clear reset
  * @pdev: port platform device.
  *
  * Enable Port by clear the port soft reset bit, which is set by default.
  * The AFU is unable to respond to any MMIO access while in reset.
- * port_enable function should only be used after port_disable function.
+ * __afu_port_enable function should only be used after __afu_port_disable
+ * function.
+ *
+ * The caller needs to hold lock for protection.
  */
-static void port_enable(struct platform_device *pdev)
+void __afu_port_enable(struct platform_device *pdev)
 {
 	struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	void __iomem *base;
···
 #define RST_POLL_TIMEOUT 1000 /* us */
 
 /**
- * port_disable - disable a port
+ * __afu_port_disable - disable a port by hold reset
  * @pdev: port platform device.
  *
- * Disable Port by setting the port soft reset bit, it puts the port into
- * reset.
+ * Disable Port by setting the port soft reset bit, it puts the port into reset.
+ *
+ * The caller needs to hold lock for protection.
  */
-static int port_disable(struct platform_device *pdev)
+int __afu_port_disable(struct platform_device *pdev)
 {
 	struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	void __iomem *base;
···
 {
 	int ret;
 
-	ret = port_disable(pdev);
+	ret = __afu_port_disable(pdev);
 	if (!ret)
-		port_enable(pdev);
+		__afu_port_enable(pdev);
 
 	return ret;
 }
···
 }
 static DEVICE_ATTR_RO(power_state);
 
+static ssize_t
+userclk_freqcmd_store(struct device *dev, struct device_attribute *attr,
+		      const char *buf, size_t count)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	u64 userclk_freq_cmd;
+	void __iomem *base;
+
+	if (kstrtou64(buf, 0, &userclk_freq_cmd))
+		return -EINVAL;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_HEADER);
+
+	mutex_lock(&pdata->lock);
+	writeq(userclk_freq_cmd, base + PORT_HDR_USRCLK_CMD0);
+	mutex_unlock(&pdata->lock);
+
+	return count;
+}
+static DEVICE_ATTR_WO(userclk_freqcmd);
+
+static ssize_t
+userclk_freqcntrcmd_store(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	u64 userclk_freqcntr_cmd;
+	void __iomem *base;
+
+	if (kstrtou64(buf, 0, &userclk_freqcntr_cmd))
+		return -EINVAL;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_HEADER);
+
+	mutex_lock(&pdata->lock);
+	writeq(userclk_freqcntr_cmd, base + PORT_HDR_USRCLK_CMD1);
+	mutex_unlock(&pdata->lock);
+
+	return count;
+}
+static DEVICE_ATTR_WO(userclk_freqcntrcmd);
+
+static ssize_t
+userclk_freqsts_show(struct device *dev, struct device_attribute *attr,
+		     char *buf)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	u64 userclk_freqsts;
+	void __iomem *base;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_HEADER);
+
+	mutex_lock(&pdata->lock);
+	userclk_freqsts = readq(base + PORT_HDR_USRCLK_STS0);
+	mutex_unlock(&pdata->lock);
+
+	return sprintf(buf, "0x%llx\n", (unsigned long long)userclk_freqsts);
+}
+static DEVICE_ATTR_RO(userclk_freqsts);
+
+static ssize_t
+userclk_freqcntrsts_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	u64 userclk_freqcntrsts;
+	void __iomem *base;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_HEADER);
+
+	mutex_lock(&pdata->lock);
+	userclk_freqcntrsts = readq(base + PORT_HDR_USRCLK_STS1);
+	mutex_unlock(&pdata->lock);
+
+	return sprintf(buf, "0x%llx\n",
+		       (unsigned long long)userclk_freqcntrsts);
+}
+static DEVICE_ATTR_RO(userclk_freqcntrsts);
+
 static struct attribute *port_hdr_attrs[] = {
 	&dev_attr_id.attr,
 	&dev_attr_ltr.attr,
 	&dev_attr_ap1_event.attr,
 	&dev_attr_ap2_event.attr,
 	&dev_attr_power_state.attr,
+	&dev_attr_userclk_freqcmd.attr,
+	&dev_attr_userclk_freqcntrcmd.attr,
+	&dev_attr_userclk_freqsts.attr,
+	&dev_attr_userclk_freqcntrsts.attr,
 	NULL,
 };
-ATTRIBUTE_GROUPS(port_hdr);
+
+static umode_t port_hdr_attrs_visible(struct kobject *kobj,
+				      struct attribute *attr, int n)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	umode_t mode = attr->mode;
+	void __iomem *base;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_HEADER);
+
+	if (dfl_feature_revision(base) > 0) {
+		/*
+		 * userclk sysfs interfaces are only visible in case port
+		 * revision is 0, as hardware with revision >0 doesn't
+		 * support this.
+		 */
+		if (attr == &dev_attr_userclk_freqcmd.attr ||
+		    attr == &dev_attr_userclk_freqcntrcmd.attr ||
+		    attr == &dev_attr_userclk_freqsts.attr ||
+		    attr == &dev_attr_userclk_freqcntrsts.attr)
+			mode = 0;
+	}
+
+	return mode;
+}
+
+static const struct attribute_group port_hdr_group = {
+	.attrs      = port_hdr_attrs,
+	.is_visible = port_hdr_attrs_visible,
+};
 
 static int port_hdr_init(struct platform_device *pdev,
 			 struct dfl_feature *feature)
 {
-	dev_dbg(&pdev->dev, "PORT HDR Init.\n");
-
 	port_reset(pdev);
 
-	return device_add_groups(&pdev->dev, port_hdr_groups);
-}
-
-static void port_hdr_uinit(struct platform_device *pdev,
-			   struct dfl_feature *feature)
-{
-	dev_dbg(&pdev->dev, "PORT HDR UInit.\n");
-
-	device_remove_groups(&pdev->dev, port_hdr_groups);
+	return 0;
 }
 
 static long
···
 
 static const struct dfl_feature_ops port_hdr_ops = {
 	.init = port_hdr_init,
-	.uinit = port_hdr_uinit,
 	.ioctl = port_hdr_ioctl,
 };
 
···
 	&dev_attr_afu_id.attr,
 	NULL
 };
-ATTRIBUTE_GROUPS(port_afu);
+
+static umode_t port_afu_attrs_visible(struct kobject *kobj,
+				      struct attribute *attr, int n)
+{
+	struct device *dev = kobj_to_dev(kobj);
+
+	/*
+	 * sysfs entries are visible only if related private feature is
+	 * enumerated.
+	 */
+	if (!dfl_get_feature_by_id(dev, PORT_FEATURE_ID_AFU))
+		return 0;
+
+	return attr->mode;
+}
+
+static const struct attribute_group port_afu_group = {
+	.attrs      = port_afu_attrs,
+	.is_visible = port_afu_attrs_visible,
+};
 
 static int port_afu_init(struct platform_device *pdev,
 			 struct dfl_feature *feature)
 {
 	struct resource *res = &pdev->resource[feature->resource_index];
-	int ret;
 
-	dev_dbg(&pdev->dev, "PORT AFU Init.\n");
-
-	ret = afu_mmio_region_add(dev_get_platdata(&pdev->dev),
-				  DFL_PORT_REGION_INDEX_AFU, resource_size(res),
-				  res->start, DFL_PORT_REGION_READ |
-				  DFL_PORT_REGION_WRITE | DFL_PORT_REGION_MMAP);
-	if (ret)
-		return ret;
-
-	return device_add_groups(&pdev->dev, port_afu_groups);
-}
-
-static void port_afu_uinit(struct platform_device *pdev,
-			   struct dfl_feature *feature)
-{
-	dev_dbg(&pdev->dev, "PORT AFU UInit.\n");
-
-	device_remove_groups(&pdev->dev, port_afu_groups);
+	return afu_mmio_region_add(dev_get_platdata(&pdev->dev),
+				   DFL_PORT_REGION_INDEX_AFU,
+				   resource_size(res), res->start,
+				   DFL_PORT_REGION_MMAP | DFL_PORT_REGION_READ |
+				   DFL_PORT_REGION_WRITE);
 }
 
 static const struct dfl_feature_id port_afu_id_table[] = {
···
 
 static const struct dfl_feature_ops port_afu_ops = {
 	.init = port_afu_init,
-	.uinit = port_afu_uinit,
+};
+
+static int port_stp_init(struct platform_device *pdev,
+			 struct dfl_feature *feature)
+{
+	struct resource *res = &pdev->resource[feature->resource_index];
+
+	return afu_mmio_region_add(dev_get_platdata(&pdev->dev),
+				   DFL_PORT_REGION_INDEX_STP,
+				   resource_size(res), res->start,
+				   DFL_PORT_REGION_MMAP | DFL_PORT_REGION_READ |
+				   DFL_PORT_REGION_WRITE);
+}
+
+static const struct dfl_feature_id port_stp_id_table[] = {
+	{.id = PORT_FEATURE_ID_STP,},
+	{0,}
+};
+
+static const struct dfl_feature_ops port_stp_ops = {
+	.init = port_stp_init,
 };
 
 static struct dfl_feature_driver port_feature_drvs[] = {
···
 	{
 		.id_table = port_afu_id_table,
 		.ops = &port_afu_ops,
+	},
+	{
+		.id_table = port_err_id_table,
+		.ops = &port_err_ops,
+	},
+	{
+		.id_table = port_stp_id_table,
+		.ops = &port_stp_ops,
 	},
 	{
 		.ops = NULL,
···
 
 	mutex_lock(&pdata->lock);
 	if (enable)
-		port_enable(pdev);
+		__afu_port_enable(pdev);
 	else
-		ret = port_disable(pdev);
+		ret = __afu_port_disable(pdev);
 	mutex_unlock(&pdata->lock);
 
 	return ret;
···
 	return 0;
 }
 
+static const struct attribute_group *afu_dev_groups[] = {
+	&port_hdr_group,
+	&port_afu_group,
+	&port_err_group,
+	NULL
+};
+
 static struct platform_driver afu_driver = {
 	.driver	= {
-		.name    = DFL_FPGA_FEATURE_DEV_PORT,
+		.name	    = DFL_FPGA_FEATURE_DEV_PORT,
+		.dev_groups = afu_dev_groups,
 	},
 	.probe   = afu_probe,
 	.remove  = afu_remove,

drivers/fpga/dfl-afu.h

···
 	struct dfl_feature_platform_data *pdata;
 };
 
+/* hold pdata->lock when call __afu_port_enable/disable */
+void __afu_port_enable(struct platform_device *pdev);
+int __afu_port_disable(struct platform_device *pdev);
+
 void afu_mmio_region_init(struct dfl_feature_platform_data *pdata);
 int afu_mmio_region_add(struct dfl_feature_platform_data *pdata,
 			u32 region_index, u64 region_size, u64 phys, u32 flags);
···
 struct dfl_afu_dma_region *
 afu_dma_region_find(struct dfl_feature_platform_data *pdata,
 		    u64 iova, u64 size);
+
+extern const struct dfl_feature_ops port_err_ops;
+extern const struct dfl_feature_id port_err_id_table[];
+extern const struct attribute_group port_err_group;
+
 #endif /* __DFL_AFU_H */

drivers/fpga/dfl-fme-error.c

···
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for FPGA Management Engine Error Management
+ *
+ * Copyright 2019 Intel Corporation, Inc.
+ *
+ * Authors:
+ *   Kang Luwei <[e-mail]>
+ *   Xiao Guangrong <[e-mail]>
+ *   Wu Hao <[e-mail]>
+ *   Joseph Grecco <[e-mail]>
+ *   Enno Luebbers <[e-mail]>
+ *   Tim Whisonant <[e-mail]>
+ *   Ananda Ravuri <[e-mail]>
+ *   Mitchel, Henry <[e-mail]>
+ */
+
+#include <linux/uaccess.h>
+
+#include "dfl.h"
+#include "dfl-fme.h"
+
+#define FME_ERROR_MASK		0x8
+#define FME_ERROR		0x10
+#define MBP_ERROR		BIT_ULL(6)
+#define PCIE0_ERROR_MASK	0x18
+#define PCIE0_ERROR		0x20
+#define PCIE1_ERROR_MASK	0x28
+#define PCIE1_ERROR		0x30
+#define FME_FIRST_ERROR		0x38
+#define FME_NEXT_ERROR		0x40
+#define RAS_NONFAT_ERROR_MASK	0x48
+#define RAS_NONFAT_ERROR	0x50
+#define RAS_CATFAT_ERROR_MASK	0x58
+#define RAS_CATFAT_ERROR	0x60
+#define RAS_ERROR_INJECT	0x68
+#define INJECT_ERROR_MASK	GENMASK_ULL(2, 0)
+
+#define ERROR_MASK		GENMASK_ULL(63, 0)
+
+static ssize_t pcie0_errors_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	u64 value;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	mutex_lock(&pdata->lock);
+	value = readq(base + PCIE0_ERROR);
+	mutex_unlock(&pdata->lock);
+
+	return sprintf(buf, "0x%llx\n", (unsigned long long)value);
+}
+
+static ssize_t pcie0_errors_store(struct device *dev,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	int ret = 0;
+	u64 v, val;
+
+	if (kstrtou64(buf, 0, &val))
+		return -EINVAL;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	mutex_lock(&pdata->lock);
+	writeq(GENMASK_ULL(63, 0), base + PCIE0_ERROR_MASK);
+
+	v = readq(base + PCIE0_ERROR);
+	if (val == v)
+		writeq(v, base + PCIE0_ERROR);
+	else
+		ret = -EINVAL;
+
+	writeq(0ULL, base + PCIE0_ERROR_MASK);
+	mutex_unlock(&pdata->lock);
+	return ret ? ret : count;
+}
+static DEVICE_ATTR_RW(pcie0_errors);
+
+static ssize_t pcie1_errors_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	u64 value;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	mutex_lock(&pdata->lock);
+	value = readq(base + PCIE1_ERROR);
+	mutex_unlock(&pdata->lock);
+
+	return sprintf(buf, "0x%llx\n", (unsigned long long)value);
+}
+
+static ssize_t pcie1_errors_store(struct device *dev,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	int ret = 0;
+	u64 v, val;
+
+	if (kstrtou64(buf, 0, &val))
+		return -EINVAL;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	mutex_lock(&pdata->lock);
+	writeq(GENMASK_ULL(63, 0), base + PCIE1_ERROR_MASK);
+
+	v = readq(base + PCIE1_ERROR);
+	if (val == v)
+		writeq(v, base + PCIE1_ERROR);
+	else
+		ret = -EINVAL;
+
+	writeq(0ULL, base + PCIE1_ERROR_MASK);
+	mutex_unlock(&pdata->lock);
+	return ret ? ret : count;
+}
+static DEVICE_ATTR_RW(pcie1_errors);
+
+static ssize_t nonfatal_errors_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	void __iomem *base;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	return sprintf(buf, "0x%llx\n",
+		       (unsigned long long)readq(base + RAS_NONFAT_ERROR));
+}
+static DEVICE_ATTR_RO(nonfatal_errors);
+
+static ssize_t catfatal_errors_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	void __iomem *base;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	return sprintf(buf, "0x%llx\n",
+		       (unsigned long long)readq(base + RAS_CATFAT_ERROR));
+}
+static DEVICE_ATTR_RO(catfatal_errors);
+
+static ssize_t inject_errors_show(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	u64 v;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	mutex_lock(&pdata->lock);
+	v = readq(base + RAS_ERROR_INJECT);
+	mutex_unlock(&pdata->lock);
+
+	return sprintf(buf, "0x%llx\n",
+		       (unsigned long long)FIELD_GET(INJECT_ERROR_MASK, v));
+}
+
+static ssize_t inject_errors_store(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf, size_t count)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	u8 inject_error;
+	u64 v;
+
+	if (kstrtou8(buf, 0, &inject_error))
+		return -EINVAL;
+
+	if (inject_error & ~INJECT_ERROR_MASK)
+		return -EINVAL;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	mutex_lock(&pdata->lock);
+	v = readq(base + RAS_ERROR_INJECT);
+	v &= ~INJECT_ERROR_MASK;
+	v |= FIELD_PREP(INJECT_ERROR_MASK, inject_error);
+	writeq(v, base + RAS_ERROR_INJECT);
+	mutex_unlock(&pdata->lock);
+
+	return count;
+}
+static DEVICE_ATTR_RW(inject_errors);
+
+static ssize_t fme_errors_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	u64 value;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	mutex_lock(&pdata->lock);
+	value = readq(base + FME_ERROR);
+	mutex_unlock(&pdata->lock);
+
+	return sprintf(buf, "0x%llx\n", (unsigned long long)value);
+}
+
+static ssize_t fme_errors_store(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	u64 v, val;
+	int ret = 0;
+
+	if (kstrtou64(buf, 0, &val))
+		return -EINVAL;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	mutex_lock(&pdata->lock);
+	writeq(GENMASK_ULL(63, 0), base + FME_ERROR_MASK);
+
+	v = readq(base + FME_ERROR);
+	if (val == v)
+		writeq(v, base + FME_ERROR);
+	else
+		ret = -EINVAL;
+
+	/* Workaround: disable MBP_ERROR if feature revision is 0 */
+	writeq(dfl_feature_revision(base) ? 0ULL : MBP_ERROR,
+	       base + FME_ERROR_MASK);
+	mutex_unlock(&pdata->lock);
+	return ret ? ret : count;
+}
+static DEVICE_ATTR_RW(fme_errors);
+
+static ssize_t first_error_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	u64 value;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	mutex_lock(&pdata->lock);
+	value = readq(base + FME_FIRST_ERROR);
+	mutex_unlock(&pdata->lock);
+
+	return sprintf(buf, "0x%llx\n", (unsigned long long)value);
+}
+static DEVICE_ATTR_RO(first_error);
+
+static ssize_t next_error_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+	u64 value;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	mutex_lock(&pdata->lock);
+	value = readq(base + FME_NEXT_ERROR);
+	mutex_unlock(&pdata->lock);
+
+	return sprintf(buf, "0x%llx\n", (unsigned long long)value);
+}
+static DEVICE_ATTR_RO(next_error);
+
+static struct attribute *fme_global_err_attrs[] = {
+	&dev_attr_pcie0_errors.attr,
+	&dev_attr_pcie1_errors.attr,
+	&dev_attr_nonfatal_errors.attr,
+	&dev_attr_catfatal_errors.attr,
+	&dev_attr_inject_errors.attr,
+	&dev_attr_fme_errors.attr,
+	&dev_attr_first_error.attr,
+	&dev_attr_next_error.attr,
+	NULL,
+};
+
+static umode_t fme_global_err_attrs_visible(struct kobject *kobj,
+					    struct attribute *attr, int n)
+{
+	struct device *dev = kobj_to_dev(kobj);
+
+	/*
+	 * sysfs entries are visible only if related private feature is
+	 * enumerated.
+	 */
+	if (!dfl_get_feature_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR))
+		return 0;
+
+	return attr->mode;
+}
+
+const struct attribute_group fme_global_err_group = {
+	.name       = "errors",
+	.attrs      = fme_global_err_attrs,
+	.is_visible = fme_global_err_attrs_visible,
+};
+
+static void fme_err_mask(struct device *dev, bool mask)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
+	void __iomem *base;
+
+	base = dfl_get_feature_ioaddr_by_id(dev, FME_FEATURE_ID_GLOBAL_ERR);
+
+	mutex_lock(&pdata->lock);
+
+	/* Workaround: keep MBP_ERROR always masked if revision is 0 */
+	if (dfl_feature_revision(base))
+		writeq(mask ? ERROR_MASK : 0, base + FME_ERROR_MASK);
+	else
+		writeq(mask ? ERROR_MASK : MBP_ERROR, base + FME_ERROR_MASK);
+
+	writeq(mask ? ERROR_MASK : 0, base + PCIE0_ERROR_MASK);
+	writeq(mask ? ERROR_MASK : 0, base + PCIE1_ERROR_MASK);
+	writeq(mask ? ERROR_MASK : 0, base + RAS_NONFAT_ERROR_MASK);
+	writeq(mask ? ERROR_MASK : 0, base + RAS_CATFAT_ERROR_MASK);
+
+	mutex_unlock(&pdata->lock);
+}
+
+static int fme_global_err_init(struct platform_device *pdev,
+			       struct dfl_feature *feature)
+{
+	fme_err_mask(&pdev->dev, false);
+
+	return 0;
+}
+
+static void fme_global_err_uinit(struct platform_device *pdev,
+				 struct dfl_feature *feature)
+{
+	fme_err_mask(&pdev->dev, true);
+}
+
+const struct dfl_feature_id fme_global_err_id_table[] = {
+	{.id = FME_FEATURE_ID_GLOBAL_ERR,},
+	{0,}
+};
+
+const struct dfl_feature_ops fme_global_err_ops = {
+	.init = fme_global_err_init,
+	.uinit = fme_global_err_uinit,
+};

drivers/fpga/dfl-fme-main.c

···
 	&dev_attr_socket_id.attr,
 	NULL,
 };
-ATTRIBUTE_GROUPS(fme_hdr);
 
-static int fme_hdr_init(struct platform_device *pdev,
-			struct dfl_feature *feature)
-{
-	void __iomem *base = feature->ioaddr;
-	int ret;
-
-	dev_dbg(&pdev->dev, "FME HDR Init.\n");
-	dev_dbg(&pdev->dev, "FME cap %llx.\n",
-		(unsigned long long)readq(base + FME_HDR_CAP));
-
-	ret = device_add_groups(&pdev->dev, fme_hdr_groups);
-	if (ret)
-		return ret;
-
-	return 0;
-}
-
-static void fme_hdr_uinit(struct platform_device *pdev,
-			  struct dfl_feature *feature)
-{
-	dev_dbg(&pdev->dev, "FME HDR UInit.\n");
-	device_remove_groups(&pdev->dev, fme_hdr_groups);
-}
+static const struct attribute_group fme_hdr_group = {
+	.attrs = fme_hdr_attrs,
+};
 
 static long fme_hdr_ioctl_release_port(struct dfl_feature_platform_data *pdata,
 				       unsigned long arg)
···
 };
 
 static const struct dfl_feature_ops fme_hdr_ops = {
-	.init = fme_hdr_init,
-	.uinit = fme_hdr_uinit,
 	.ioctl = fme_hdr_ioctl,
 };
 
···
 	{
 		.id_table = fme_pr_mgmt_id_table,
 		.ops = &fme_pr_mgmt_ops,
+	},
+	{
+		.id_table = fme_global_err_id_table,
+		.ops = &fme_global_err_ops,
 	},
 	{
 		.ops = NULL,
···
 	return 0;
 }
 
+static const struct attribute_group *fme_dev_groups[] = {
+	&fme_hdr_group,
+	&fme_global_err_group,
+	NULL
+};
+
 static struct platform_driver fme_driver = {
 	.driver	= {
-		.name    = DFL_FPGA_FEATURE_DEV_FME,
+		.name       = DFL_FPGA_FEATURE_DEV_FME,
+		.dev_groups = fme_dev_groups,
 	},
 	.probe   = fme_probe,
 	.remove  = fme_remove,

drivers/fpga/dfl-fme.h

···
 
 extern const struct dfl_feature_ops fme_pr_mgmt_ops;
 extern const struct dfl_feature_id fme_pr_mgmt_id_table[];
+extern const struct dfl_feature_ops fme_global_err_ops;
+extern const struct dfl_feature_id fme_global_err_id_table[];
+extern const struct attribute_group fme_global_err_group;
 
 #endif /* __DFL_FME_H */

drivers/fpga/dfl.c

···
 				     struct dfl_feature *feature,
 				     struct dfl_feature_driver *drv)
 {
-	int ret;
+	int ret = 0;
 
-	ret = drv->ops->init(pdev, feature);
-	if (ret)
-		return ret;
+	if (drv->ops->init) {
+		ret = drv->ops->init(pdev, feature);
+		if (ret)
+			return ret;
+	}
 
 	feature->ops = drv->ops;
 

drivers/fpga/dfl.h

···
 #define PORT_HDR_CAP		0x30
 #define PORT_HDR_CTRL		0x38
 #define PORT_HDR_STS		0x40
+#define PORT_HDR_USRCLK_CMD0	0x50
+#define PORT_HDR_USRCLK_CMD1	0x58
+#define PORT_HDR_USRCLK_STS0	0x60
+#define PORT_HDR_USRCLK_STS1	0x68
 
 /* Port Capability Register Bitfield */
 #define PORT_CAP_PORT_NUM	GENMASK_ULL(1, 0)	/* ID of this port */
···
 
 	return (FIELD_GET(DFH_TYPE, v) == DFH_TYPE_FIU) &&
 		(FIELD_GET(DFH_ID, v) == DFH_ID_FIU_PORT);
+}
+
+static inline u8 dfl_feature_revision(void __iomem *base)
+{
+	return (u8)FIELD_GET(DFH_REVISION, readq(base + DFH));
 }
 
 /**

include/linux/device.h

···
  * @resume:	Called to bring a device from sleep mode.
  * @groups:	Default attributes that get created by the driver core
  *		automatically.
+ * @dev_groups:	Additional attributes attached to device instance once the
+ *		it is bound to the driver.
  * @pm:		Power management operations of the device which matched
  *		this driver.
  * @coredump:	Called when sysfs entry is written to. The device driver
···
 	int (*suspend) (struct device *dev, pm_message_t state);
 	int (*resume) (struct device *dev);
 	const struct attribute_group **groups;
+	const struct attribute_group **dev_groups;
 
 	const struct dev_pm_ops *pm;
 	void (*coredump) (struct device *dev);