Re: [PATCH V9 XRT Alveo 04/14] fpga: xrt: xrt-lib driver manager

From: Lizhi Hou
Date: Mon Oct 25 2021 - 20:47:22 EST


Hi Yilun,

Thanks a lot for reviewing the patch. On Rob's advice we are exploring the device tree changes which will likely have some software interface changes. Will get back to you.

Lizhi

On 10/25/21 1:01 AM, Xu Yilun wrote:

On Mon, Aug 02, 2021 at 09:05:11AM -0700, Lizhi Hou wrote:
xrt-lib kernel module infrastructure code to register and manage all
leaf driver modules.

Signed-off-by: Sonal Santan <sonal.santan@xxxxxxxxxx>
Signed-off-by: Max Zhen <max.zhen@xxxxxxxxxx>
Signed-off-by: Lizhi Hou <lizhi.hou@xxxxxxxxxx>
Reviewed-by: Tom Rix <trix@xxxxxxxxxx>
---
drivers/fpga/xrt/include/subdev_id.h | 39 +++
drivers/fpga/xrt/include/xdevice.h | 141 ++++++++
drivers/fpga/xrt/include/xleaf.h | 205 +++++++++++
drivers/fpga/xrt/include/xleaf/clkfreq.h | 21 ++
drivers/fpga/xrt/include/xleaf/clock.h | 29 ++
.../fpga/xrt/include/xleaf/ddr_calibration.h | 28 ++
drivers/fpga/xrt/include/xleaf/devctl.h | 40 +++
drivers/fpga/xrt/lib/lib-drv.c | 318 ++++++++++++++++++
drivers/fpga/xrt/lib/lib-drv.h | 21 ++
9 files changed, 842 insertions(+)
create mode 100644 drivers/fpga/xrt/include/subdev_id.h
create mode 100644 drivers/fpga/xrt/include/xdevice.h
create mode 100644 drivers/fpga/xrt/include/xleaf.h
create mode 100644 drivers/fpga/xrt/include/xleaf/clkfreq.h
create mode 100644 drivers/fpga/xrt/include/xleaf/clock.h
create mode 100644 drivers/fpga/xrt/include/xleaf/ddr_calibration.h
create mode 100644 drivers/fpga/xrt/include/xleaf/devctl.h
create mode 100644 drivers/fpga/xrt/lib/lib-drv.c
create mode 100644 drivers/fpga/xrt/lib/lib-drv.h

diff --git a/drivers/fpga/xrt/include/subdev_id.h b/drivers/fpga/xrt/include/subdev_id.h
new file mode 100644
index 000000000000..02df4b939a1b
--- /dev/null
+++ b/drivers/fpga/xrt/include/subdev_id.h
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ * Cheng Zhen <maxz@xxxxxxxxxx>
+ */
+
+#ifndef _XRT_SUBDEV_ID_H_
+#define _XRT_SUBDEV_ID_H_
+
+/*
+ * Every subdev driver has an ID for others to refer to it. There can be multiple number of
+ * instances of a subdev driver. A <subdev_id, subdev_instance> tuple is a unique identification
+ * of a specific instance of a subdev driver.
+ */
+enum xrt_subdev_id {
+ XRT_SUBDEV_INVALID = 0,
+ XRT_SUBDEV_GRP,
+ XRT_SUBDEV_VSEC,
+ XRT_SUBDEV_VSEC_GOLDEN,
+ XRT_SUBDEV_DEVCTL,
+ XRT_SUBDEV_AXIGATE,
+ XRT_SUBDEV_ICAP,
+ XRT_SUBDEV_TEST,
+ XRT_SUBDEV_MGMT_MAIN,
+ XRT_SUBDEV_QSPI,
+ XRT_SUBDEV_MAILBOX,
+ XRT_SUBDEV_CMC,
+ XRT_SUBDEV_CALIB,
+ XRT_SUBDEV_CLKFREQ,
+ XRT_SUBDEV_CLOCK,
+ XRT_SUBDEV_SRSR,
+ XRT_SUBDEV_UCS,
+ XRT_SUBDEV_NUM, /* Total number of subdevs. */
+ XRT_ROOT = -1, /* Special ID for root driver. */
+};
+
+#endif /* _XRT_SUBDEV_ID_H_ */
diff --git a/drivers/fpga/xrt/include/xdevice.h b/drivers/fpga/xrt/include/xdevice.h
new file mode 100644
index 000000000000..b40ebe98b54d
--- /dev/null
+++ b/drivers/fpga/xrt/include/xdevice.h
@@ -0,0 +1,141 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ * Lizhi Hou <lizhi.hou@xxxxxxxxxx>
+ */
+
+#ifndef _XRT_DEVICE_H_
+#define _XRT_DEVICE_H_
+
+#include <linux/fs.h>
+#include <linux/cdev.h>
+
+#define XRT_MAX_DEVICE_NODES 128
+#define XRT_INVALID_DEVICE_INST (XRT_MAX_DEVICE_NODES + 1)
+
+enum {
+ XRT_DEVICE_STATE_NONE = 0,
+ XRT_DEVICE_STATE_ADDED
+};
+
+/*
+ * struct xrt_device - represent an xrt device on xrt bus
+ *
+ * dev: generic device interface.
+ * subdev_id: id of the xrt device. See enum xrt_subdev_id.
+ * name: name of the xrt device.
+ * instance: instance of the xrt device. The xrt device with same id can have
+ * more than 1 instances.
+ * state: current state of the xrt device.
+ * num_resources: The total number of resource for the xrt device.
+ * resource: point to the xrt device resource array.
+ * sdev_data: private data pointer.
+ */
+struct xrt_device {
+ struct device dev;
+ u32 subdev_id;
+ const char *name;
+ u32 instance;
+ u32 state;
+ u32 num_resources;
+ struct resource *resource;
+ void *sdev_data;
+};
+
+/*
+ * If populated by xrt device driver, infra will handle the mechanics of
+ * char device (un)registration.
+ */
+enum xrt_dev_file_mode {
+ /* Infra create cdev, default file name */
+ XRT_DEV_FILE_DEFAULT = 0,
+ /* Infra create cdev, need to encode inst num in file name */
+ XRT_DEV_FILE_MULTI_INST,
+ /* No auto creation of cdev by infra, leaf handles it by itself */
+ XRT_DEV_FILE_NO_AUTO,
+};
+
+struct xrt_dev_file_ops {
+ const struct file_operations xsf_ops;
+ dev_t xsf_dev_t;
+ const char *xsf_dev_name;
+ enum xrt_dev_file_mode xsf_mode;
+};
+
+/*
+ * this struct define the endpoints belong to the same xrt device
+ * ep_name: endpoint name
+ * compat: compatible string
+ */
+struct xrt_dev_ep_names {
+ const char *ep_name;
+ const char *compat;
+};
+
+struct xrt_dev_endpoints {
+ struct xrt_dev_ep_names *xse_names;
+ /* minimum number of endpoints to support the subdevice */
+ u32 xse_min_ep;
Why some device must have several DT nodes?

+};
+
+/*
+ * struct xrt_driver - represent a xrt device driver
+ *
+ * driver: driver model structure.
+ * subdev_id: id of the xrt device. See enum xrt_subdev_id.
+ * file_ops: character device name and callbacks.
+ * probe: mandatory callback for device binding.
+ * remove: callback for device unbinding.
+ * leaf_call: callback for servicing other leaf drivers.
+ */
+struct xrt_driver {
+ struct device_driver driver;
+ u32 subdev_id;
+ struct xrt_dev_file_ops file_ops;
+ struct xrt_dev_endpoints *endpoints;
No DOC for this field.

Seems this is to list the device types the driver supports, but usually
this is done by an id_table in driver.

+
+ /*
+ * Subdev driver callbacks populated by subdev driver.
+ */
+ int (*probe)(struct xrt_device *xrt_dev);
+ void (*remove)(struct xrt_device *xrt_dev);
+ /*
+ * If leaf_call is defined, these are called by other leaf drivers.
+ * Note that root driver may call into leaf_call of a group driver.
+ */
+ int (*leaf_call)(struct xrt_device *xrt_dev, u32 cmd, void *arg);
Why this is needed? If a function of a driver module needs to be called
by other modules, just export the function.

+};
+
+#define to_xrt_dev(d) container_of(d, struct xrt_device, dev)
+#define to_xrt_drv(d) container_of(d, struct xrt_driver, driver)
+
+static inline void *xrt_get_drvdata(const struct xrt_device *xdev)
+{
+ return dev_get_drvdata(&xdev->dev);
+}
+
+static inline void xrt_set_drvdata(struct xrt_device *xdev, void *data)
+{
+ dev_set_drvdata(&xdev->dev, data);
+}
+
+static inline void *xrt_get_xdev_data(struct device *dev)
+{
+ struct xrt_device *xdev = to_xrt_dev(dev);
+
+ return xdev->sdev_data;
+}
+
+struct xrt_device *
+xrt_device_register(struct device *parent, u32 id,
+ struct resource *res, u32 res_num,
+ void *pdata, size_t data_sz);
+void xrt_device_unregister(struct xrt_device *xdev);
+int xrt_register_driver(struct xrt_driver *drv);
+void xrt_unregister_driver(struct xrt_driver *drv);
+void *xrt_get_xdev_data(struct device *dev);
+struct resource *xrt_get_resource(struct xrt_device *xdev, u32 type, u32 num);
+
+#endif /* _XRT_DEVICE_H_ */
diff --git a/drivers/fpga/xrt/include/xleaf.h b/drivers/fpga/xrt/include/xleaf.h
new file mode 100644
index 000000000000..f065fc766e0f
--- /dev/null
+++ b/drivers/fpga/xrt/include/xleaf.h
@@ -0,0 +1,205 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ * Cheng Zhen <maxz@xxxxxxxxxx>
+ * Sonal Santan <sonal.santan@xxxxxxxxxx>
+ */
+
+#ifndef _XRT_XLEAF_H_
+#define _XRT_XLEAF_H_
+
+#include <linux/mod_devicetable.h>
+#include "xdevice.h"
+#include "subdev_id.h"
+#include "xroot.h"
+#include "events.h"
+
+/* All subdev drivers should use below common routines to print out msg. */
+#define DEV(xdev) (&(xdev)->dev)
+#define DEV_PDATA(xdev) \
+ ((struct xrt_subdev_platdata *)xrt_get_xdev_data(DEV(xdev)))
+#define DEV_FILE_OPS(xdev) \
+ (&(to_xrt_drv((xdev)->dev.driver))->file_ops)
+#define FMT_PRT(prt_fn, xdev, fmt, args...) \
+ ({typeof(xdev) (_xdev) = (xdev); \
+ prt_fn(DEV(_xdev), "%s %s: " fmt, \
+ DEV_PDATA(_xdev)->xsp_root_name, __func__, ##args); })
+#define xrt_err(xdev, fmt, args...) FMT_PRT(dev_err, xdev, fmt, ##args)
+#define xrt_warn(xdev, fmt, args...) FMT_PRT(dev_warn, xdev, fmt, ##args)
+#define xrt_info(xdev, fmt, args...) FMT_PRT(dev_info, xdev, fmt, ##args)
+#define xrt_dbg(xdev, fmt, args...) FMT_PRT(dev_dbg, xdev, fmt, ##args)
+
+#define XRT_DEFINE_REGMAP_CONFIG(config_name) \
+ static const struct regmap_config config_name = { \
+ .reg_bits = 32, \
+ .val_bits = 32, \
+ .reg_stride = 4, \
+ .max_register = 0x1000, \
+ }
+
+enum {
+ /* Starting cmd for common leaf cmd implemented by all leaves. */
+ XRT_XLEAF_COMMON_BASE = 0,
+ /* Starting cmd for leaves' specific leaf cmds. */
+ XRT_XLEAF_CUSTOM_BASE = 64,
+};
+
+enum xrt_xleaf_common_leaf_cmd {
+ XRT_XLEAF_EVENT = XRT_XLEAF_COMMON_BASE,
+};
+
+/*
+ * Partially initialized by the parent driver, then, passed in as subdev driver's
+ * platform data when creating subdev driver instance by calling platform
+ * device register API (xrt_device_register_data() or the likes).
Didn't find the xrt_device_register_data, should be xrt_device_register?

+ *
+ * Once device register API returns, platform driver framework makes a copy of
+ * this buffer and maintains its life cycle. The content of the buffer is
+ * completely owned by subdev driver.
Generally the platform data contains some specific description of the device, so
it should also be managered by the parent same as the device. The driver
owned data should be in dev.driver_data

+ *
+ * Thus, parent driver should be very careful when it touches this buffer
+ * again once it's handed over to subdev driver. And the data structure
+ * should not contain pointers pointing to buffers that is managed by
+ * other or parent drivers since it could have been freed before platform
+ * data buffer is freed by platform driver framework.
+ */
+struct xrt_subdev_platdata {
+ /*
+ * Per driver instance callback. The xdev points to the instance.
+ * Should always be defined for subdev driver to get service from root.
+ */
+ xrt_subdev_root_cb_t xsp_root_cb;
+ void *xsp_root_cb_arg;
+
+ /* Something to associate w/ root for msg printing. */
+ const char *xsp_root_name;
+
+ /*
+ * Char dev support for this subdev instance.
+ * Initialized by subdev driver.
+ */
+ struct cdev xsp_cdev;
+ struct device *xsp_sysdev;
+ struct mutex xsp_devnode_lock; /* devnode lock */
+ struct completion xsp_devnode_comp;
+ int xsp_devnode_ref;
+ bool xsp_devnode_online;
+ bool xsp_devnode_excl;
+
+ /*
+ * Subdev driver specific init data. The buffer should be embedded
+ * in this data structure buffer after dtb, so that it can be freed
+ * together with platform data.
+ */
+ loff_t xsp_priv_off; /* Offset into this platform data buffer. */
+ size_t xsp_priv_len;
Didn't see the usage.

+
+ /*
+ * Populated by parent driver to describe the device tree for
+ * the subdev driver to handle. Should always be last one since it's
+ * of variable length.
+ */
+ bool xsp_dtb_valid;
+ char xsp_dtb[0];
+};
+
+struct subdev_match_arg {
+ enum xrt_subdev_id id;
+ int instance;
+};
+
+bool xleaf_has_endpoint(struct xrt_device *xdev, const char *endpoint_name);
+struct xrt_device *xleaf_get_leaf(struct xrt_device *xdev,
+ xrt_subdev_match_t cb, void *arg);
+
+static inline bool subdev_match(enum xrt_subdev_id id, struct xrt_device *xdev, void *arg)
+{
+ const struct subdev_match_arg *a = (struct subdev_match_arg *)arg;
+ int instance = a->instance;
+
+ if (id != a->id)
+ return false;
+ if (instance != xdev->instance && instance != XRT_INVALID_DEVICE_INST)
+ return false;
+ return true;
+}
+
+static inline bool xrt_subdev_match_epname(enum xrt_subdev_id id,
+ struct xrt_device *xdev, void *arg)
+{
+ return xleaf_has_endpoint(xdev, arg);
+}
+
+static inline struct xrt_device *
+xleaf_get_leaf_by_id(struct xrt_device *xdev,
+ enum xrt_subdev_id id, int instance)
+{
+ struct subdev_match_arg arg = { id, instance };
+
+ return xleaf_get_leaf(xdev, subdev_match, &arg);
+}
+
+static inline struct xrt_device *
+xleaf_get_leaf_by_epname(struct xrt_device *xdev, const char *name)
+{
+ return xleaf_get_leaf(xdev, xrt_subdev_match_epname, (void *)name);
+}
+
+static inline int xleaf_call(struct xrt_device *tgt, u32 cmd, void *arg)
+{
+ return (to_xrt_drv(tgt->dev.driver)->leaf_call)(tgt, cmd, arg);
+}
+
+int xleaf_broadcast_event(struct xrt_device *xdev, enum xrt_events evt, bool async);
+int xleaf_create_group(struct xrt_device *xdev, char *dtb);
+int xleaf_destroy_group(struct xrt_device *xdev, int instance);
+void xleaf_get_root_res(struct xrt_device *xdev, u32 region_id, struct resource **res);
+void xleaf_get_root_id(struct xrt_device *xdev, unsigned short *vendor, unsigned short *device,
+ unsigned short *subvendor, unsigned short *subdevice);
+void xleaf_hot_reset(struct xrt_device *xdev);
+int xleaf_put_leaf(struct xrt_device *xdev, struct xrt_device *leaf);
+struct device *xleaf_register_hwmon(struct xrt_device *xdev, const char *name, void *drvdata,
+ const struct attribute_group **grps);
+void xleaf_unregister_hwmon(struct xrt_device *xdev, struct device *hwmon);
+int xleaf_wait_for_group_bringup(struct xrt_device *xdev);
+
+/*
+ * Character device helper APIs for use by leaf drivers
+ */
+static inline bool xleaf_devnode_enabled(struct xrt_device *xdev)
+{
+ return DEV_FILE_OPS(xdev)->xsf_ops.open;
+}
+
+int xleaf_devnode_create(struct xrt_device *xdev,
+ const char *file_name, const char *inst_name);
+void xleaf_devnode_destroy(struct xrt_device *xdev);
+
+struct xrt_device *xleaf_devnode_open_excl(struct inode *inode);
+struct xrt_device *xleaf_devnode_open(struct inode *inode);
+void xleaf_devnode_close(struct inode *inode);
+
+/* Module's init/fini routines for leaf driver in xrt-lib module */
+#define XRT_LEAF_INIT_FINI_FUNC(name) \
+void name##_leaf_init_fini(bool init) \
+{ \
+ if (init) \
+ xrt_register_driver(&xrt_##name##_driver); \
+ else \
+ xrt_unregister_driver(&xrt_##name##_driver); \
+}
+
+/* Module's init/fini routines for leaf driver in xrt-lib module */
+void group_leaf_init_fini(bool init);
+void vsec_leaf_init_fini(bool init);
+void devctl_leaf_init_fini(bool init);
+void axigate_leaf_init_fini(bool init);
+void icap_leaf_init_fini(bool init);
+void calib_leaf_init_fini(bool init);
+void clkfreq_leaf_init_fini(bool init);
+void clock_leaf_init_fini(bool init);
+void ucs_leaf_init_fini(bool init);
+
+#endif /* _XRT_LEAF_H_ */
diff --git a/drivers/fpga/xrt/include/xleaf/clkfreq.h b/drivers/fpga/xrt/include/xleaf/clkfreq.h
new file mode 100644
index 000000000000..005441d5df78
--- /dev/null
+++ b/drivers/fpga/xrt/include/xleaf/clkfreq.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ * Lizhi Hou <Lizhi.Hou@xxxxxxxxxx>
+ */
+
+#ifndef _XRT_CLKFREQ_H_
+#define _XRT_CLKFREQ_H_
+
+#include "xleaf.h"
+
+/*
+ * CLKFREQ driver leaf calls.
+ */
+enum xrt_clkfreq_leaf_cmd {
+ XRT_CLKFREQ_READ = XRT_XLEAF_CUSTOM_BASE, /* See comments in xleaf.h */
+};
+
+#endif /* _XRT_CLKFREQ_H_ */
diff --git a/drivers/fpga/xrt/include/xleaf/clock.h b/drivers/fpga/xrt/include/xleaf/clock.h
new file mode 100644
index 000000000000..1379e24fa5d0
--- /dev/null
+++ b/drivers/fpga/xrt/include/xleaf/clock.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ * Lizhi Hou <Lizhi.Hou@xxxxxxxxxx>
+ */
+
+#ifndef _XRT_CLOCK_H_
+#define _XRT_CLOCK_H_
+
+#include "xleaf.h"
+#include <linux/fpga_xrt.h>
+
+/*
+ * CLOCK driver leaf calls.
+ */
+enum xrt_clock_leaf_cmd {
+ XRT_CLOCK_SET = XRT_XLEAF_CUSTOM_BASE, /* See comments in xleaf.h */
+ XRT_CLOCK_GET,
+ XRT_CLOCK_VERIFY,
+};
+
+struct xrt_clock_get {
+ u16 freq;
+ u32 freq_cnter;
+};
+
+#endif /* _XRT_CLOCK_H_ */
diff --git a/drivers/fpga/xrt/include/xleaf/ddr_calibration.h b/drivers/fpga/xrt/include/xleaf/ddr_calibration.h
new file mode 100644
index 000000000000..c44ae30f939a
--- /dev/null
+++ b/drivers/fpga/xrt/include/xleaf/ddr_calibration.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ * Cheng Zhen <maxz@xxxxxxxxxx>
+ */
+
+#ifndef _XRT_DDR_CALIBRATION_H_
+#define _XRT_DDR_CALIBRATION_H_
+
+#include "xleaf.h"
+#include <linux/fpga-xrt.h>
+
+/*
+ * Memory calibration driver leaf calls.
+ */
+enum xrt_calib_results {
+ XRT_CALIB_UNKNOWN = 0,
+ XRT_CALIB_SUCCEEDED,
+ XRT_CALIB_FAILED,
+};
+
+enum xrt_calib_leaf_cmd {
+ XRT_CALIB_RESULT = XRT_XLEAF_CUSTOM_BASE, /* See comments in xleaf.h */
+};
+
+#endif /* _XRT_DDR_CALIBRATION_H_ */
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@xxxxxxxxxx>
+ */
+
+#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/lib-drv.c b/drivers/fpga/xrt/lib/lib-drv.c
new file mode 100644
index 000000000000..7d21ef565651
--- /dev/null
+++ b/drivers/fpga/xrt/lib/lib-drv.c
@@ -0,0 +1,318 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ * Cheng Zhen <maxz@xxxxxxxxxx>
+ * Lizhi Hou <lizhi.hou@xxxxxxxxxx>
+ */
+
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include "xleaf.h"
+#include "xroot.h"
+#include "lib-drv.h"
+
+#define XRT_IPLIB_MODULE_NAME "xrt-lib"
+#define XRT_DRVNAME(drv) ((drv)->driver.name)
+
+#define XRT_SUBDEV_ID_SHIFT 16
+#define XRT_SUBDEV_ID_MASK ((1 << XRT_SUBDEV_ID_SHIFT) - 1)
+
+struct xrt_find_drv_data {
+ enum xrt_subdev_id id;
+ struct xrt_driver *xdrv;
+};
+
+struct class *xrt_class;
+static DEFINE_IDA(xrt_device_ida);
+
+static inline u32 xrt_instance_to_id(enum xrt_subdev_id id, u32 instance)
+{
+ return (id << XRT_SUBDEV_ID_SHIFT) | instance;
+}
+
+static inline u32 xrt_id_to_instance(u32 id)
+{
+ return id & XRT_SUBDEV_ID_MASK;
+}
+
+static int xrt_bus_match(struct device *dev, struct device_driver *drv)
+{
+ struct xrt_device *xdev = to_xrt_dev(dev);
+ struct xrt_driver *xdrv = to_xrt_drv(drv);
+
+ if (xdev->subdev_id == xdrv->subdev_id)
+ return 1;
+
+ return 0;
+}
+
+static int xrt_bus_probe(struct device *dev)
+{
+ struct xrt_driver *xdrv = to_xrt_drv(dev->driver);
+ struct xrt_device *xdev = to_xrt_dev(dev);
+
+ return xdrv->probe(xdev);
+}
+
+static int xrt_bus_remove(struct device *dev)
+{
+ struct xrt_driver *xdrv = to_xrt_drv(dev->driver);
+ struct xrt_device *xdev = to_xrt_dev(dev);
+
+ if (xdrv->remove)
+ xdrv->remove(xdev);
+
+ return 0;
+}
+
+struct bus_type xrt_bus_type = {
+ .name = "xrt",
+ .match = xrt_bus_match,
+ .probe = xrt_bus_probe,
+ .remove = xrt_bus_remove,
+};
Actually I'm not sure a new bus type is needed. The bus itself is a
virtual bus and the device identifier (xdev.subdev_id) for the bus
is SW defined, then why don't we just use the name string matching and
create platform devices for each leaf?

+
+int xrt_register_driver(struct xrt_driver *drv)
+{
+ const char *drvname = XRT_DRVNAME(drv);
+ int rc = 0;
+
+ /* Initialize dev_t for char dev node. */
+ if (drv->file_ops.xsf_ops.open) {
+ rc = alloc_chrdev_region(&drv->file_ops.xsf_dev_t, 0,
+ XRT_MAX_DEVICE_NODES, drvname);
I think no need to help alloc char majors for each driver here. The
function is for driver registration, the char dev is for the actual driver
functionality and had better be managered in its own module.

I only see the xmgmt_main module needs the char dev, so maybe we only do
it in xmgmt_main init function.

+ if (rc) {
+ pr_err("failed to alloc dev minor for %s: %d\n", drvname, rc);
+ return rc;
+ }
+ } else {
+ drv->file_ops.xsf_dev_t = (dev_t)-1;
+ }
+
+ drv->driver.owner = THIS_MODULE;
+ drv->driver.bus = &xrt_bus_type;
+
+ rc = driver_register(&drv->driver);
+ if (rc) {
+ pr_err("register %s xrt driver failed\n", drvname);
+ if (drv->file_ops.xsf_dev_t != (dev_t)-1) {
+ unregister_chrdev_region(drv->file_ops.xsf_dev_t,
+ XRT_MAX_DEVICE_NODES);
+ }
+ return rc;
+ }
+
+ pr_info("%s registered successfully\n", drvname);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xrt_register_driver);
+
+void xrt_unregister_driver(struct xrt_driver *drv)
+{
+ driver_unregister(&drv->driver);
+
+ if (drv->file_ops.xsf_dev_t != (dev_t)-1)
+ unregister_chrdev_region(drv->file_ops.xsf_dev_t, XRT_MAX_DEVICE_NODES);
+}
+EXPORT_SYMBOL_GPL(xrt_unregister_driver);
+
+static int __find_driver(struct device_driver *drv, void *_data)
+{
+ struct xrt_driver *xdrv = to_xrt_drv(drv);
+ struct xrt_find_drv_data *data = _data;
+
+ if (xdrv->subdev_id == data->id) {
+ data->xdrv = xdrv;
+ return 1;
+ }
+
+ return 0;
+}
+
+const char *xrt_drv_name(enum xrt_subdev_id id)
+{
+ struct xrt_find_drv_data data = { 0 };
+
+ data.id = id;
+ bus_for_each_drv(&xrt_bus_type, NULL, &data, __find_driver);
+
+ if (data.xdrv)
+ return XRT_DRVNAME(data.xdrv);
+
+ return NULL;
+}
+
+static int xrt_drv_get_instance(enum xrt_subdev_id id)
+{
+ int ret;
+
+ ret = ida_alloc_range(&xrt_device_ida, xrt_instance_to_id(id, 0),
+ xrt_instance_to_id(id, XRT_MAX_DEVICE_NODES),
+ GFP_KERNEL);
+ if (ret < 0)
+ return ret;
+
+ return xrt_id_to_instance((u32)ret);
+}
+
+static void xrt_drv_put_instance(enum xrt_subdev_id id, int instance)
+{
+ ida_free(&xrt_device_ida, xrt_instance_to_id(id, instance));
+}
+
+struct xrt_dev_endpoints *xrt_drv_get_endpoints(enum xrt_subdev_id id)
+{
+ struct xrt_find_drv_data data = { 0 };
+
+ data.id = id;
+ bus_for_each_drv(&xrt_bus_type, NULL, &data, __find_driver);
+
+ if (data.xdrv)
+ return data.xdrv->endpoints;
+
+ return NULL;
+}
+
+static void xrt_device_release(struct device *dev)
+{
+ struct xrt_device *xdev = container_of(dev, struct xrt_device, dev);
+
+ kfree(xdev);
+}
+
+void xrt_device_unregister(struct xrt_device *xdev)
+{
+ if (xdev->state == XRT_DEVICE_STATE_ADDED)
+ device_del(&xdev->dev);
+
+ vfree(xdev->sdev_data);
+ kfree(xdev->resource);
+
+ if (xdev->instance != XRT_INVALID_DEVICE_INST)
+ xrt_drv_put_instance(xdev->subdev_id, xdev->instance);
I suggest all the free work be done in dev.release. The xrt_device may
still be accessible after this function, these resources may still be
accessed too.

+
+ if (xdev->dev.release == xrt_device_release)
+ put_device(&xdev->dev);
It is OK but unnormal, I suggest you don't integrate the error handling
of xrt_device_register here. That would make the code easier to read.

+}
+
+struct xrt_device *
+xrt_device_register(struct device *parent, u32 id,
+ struct resource *res, u32 res_num,
+ void *pdata, size_t data_sz)
+{
+ struct xrt_device *xdev = NULL;
+ int ret;
+
+ xdev = kzalloc(sizeof(*xdev), GFP_KERNEL);
+ if (!xdev)
+ return xdev;
+ xdev->instance = XRT_INVALID_DEVICE_INST;
+
+ /* Obtain dev instance number. */
+ ret = xrt_drv_get_instance(id);
+ if (ret < 0) {
+ dev_err(parent, "failed get instance, ret %d", ret);
+ goto fail;
+ }
+
+ xdev->instance = ret;
+ xdev->name = xrt_drv_name(id);
What if the xrt_driver is not loaded yet?

Normally the device represents the HW devices in system, it could be
enumerated and created no matter whether its device driver exists. So I
think some code in this patchset is not reasonable, that creates
xrt_device when the corresponding xrt_driver exists.

+ xdev->subdev_id = id;
+ device_initialize(&xdev->dev);
+ xdev->dev.release = xrt_device_release;
+ xdev->dev.parent = parent;
+
+ xdev->dev.bus = &xrt_bus_type;
+ dev_set_name(&xdev->dev, "%s.%d", xdev->name, xdev->instance);
+
+ xdev->num_resources = res_num;
+ xdev->resource = kmemdup(res, sizeof(*res) * res_num, GFP_KERNEL);
+ if (!xdev->resource)
+ goto fail;
+
+ xdev->sdev_data = vzalloc(data_sz);
vmalloc the platform_data is quite unnormal, the concern is the
performance. Maybe you should split the structures and only vmalloc
for big data chunk.

+ if (!xdev->sdev_data)
+ goto fail;
+
+ memcpy(xdev->sdev_data, pdata, data_sz);
As I can see, you need to cut and copy the selected dtb data in
platform_data for each dev. But why? Why not put the whole dtb somewhere
and let the driver access it as needed?

+
+ ret = device_add(&xdev->dev);
+ if (ret) {
+ dev_err(parent, "failed add device, ret %d", ret);
+ goto fail;
+ }
+ xdev->state = XRT_DEVICE_STATE_ADDED;
+
+ return xdev;
+
+fail:
+ xrt_device_unregister(xdev);
+ kfree(xdev);
+
+ return NULL;
+}
+
+struct resource *xrt_get_resource(struct xrt_device *xdev, u32 type, u32 num)
+{
+ u32 i;
+
+ for (i = 0; i < xdev->num_resources; i++) {
+ struct resource *r = &xdev->resource[i];
+
+ if (type == resource_type(r) && num-- == 0)
+ return r;
+ }
+ return NULL;
+}
+
+/*
+ * Leaf driver's module init/fini callbacks. This is not a open infrastructure for dynamic
+ * plugging in drivers. All drivers should be statically added.
That's not the normal way, moreover, as a FPGA, users may integrate all
kinds of IP blocks whose drivers are not belong to FPGA domain. Put them
all in FPGA folder is not a good idea.

Thanks,
Yilun

+ */
+static void (*leaf_init_fini_cbs[])(bool) = {
+ group_leaf_init_fini,
+ axigate_leaf_init_fini,
+ icap_leaf_init_fini,
+};
+
+static __init int xrt_lib_init(void)
+{
+ int ret;
+ int i;
+
+ ret = bus_register(&xrt_bus_type);
+ if (ret)
+ return ret;
+
+ xrt_class = class_create(THIS_MODULE, XRT_IPLIB_MODULE_NAME);
+ if (IS_ERR(xrt_class)) {
+ bus_unregister(&xrt_bus_type);
+ return PTR_ERR(xrt_class);
+ }
+
+ for (i = 0; i < ARRAY_SIZE(leaf_init_fini_cbs); i++)
+ leaf_init_fini_cbs[i](true);
+ return 0;
+}
+
+static __exit void xrt_lib_fini(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(leaf_init_fini_cbs); i++)
+ leaf_init_fini_cbs[i](false);
+
+ class_destroy(xrt_class);
+ bus_unregister(&xrt_bus_type);
+}
+
+module_init(xrt_lib_init);
+module_exit(xrt_lib_fini);
+
+MODULE_AUTHOR("XRT Team <runtime@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Xilinx Alveo IP Lib driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/fpga/xrt/lib/lib-drv.h b/drivers/fpga/xrt/lib/lib-drv.h
new file mode 100644
index 000000000000..0276c28e009f
--- /dev/null
+++ b/drivers/fpga/xrt/lib/lib-drv.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ * Cheng Zhen <maxz@xxxxxxxxxx>
+ */
+
+#ifndef _LIB_DRV_H_
+#define _LIB_DRV_H_
+
+#include <linux/device/class.h>
+#include <linux/device/bus.h>
+
+extern struct class *xrt_class;
+extern struct bus_type xrt_bus_type;
+
+const char *xrt_drv_name(enum xrt_subdev_id id);
+struct xrt_dev_endpoints *xrt_drv_get_endpoints(enum xrt_subdev_id id);
+
+#endif /* _LIB_DRV_H_ */
--
2.27.0