[PATCH V8 XRT Alveo 08/14] fpga: xrt: driver infrastructure

From: Lizhi Hou
Date: Mon Jul 19 2021 - 18:03:36 EST


Infrastructure code providing APIs for managing leaf driver instance
groups, facilitating inter-leaf driver calls and root calls.

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/lib/subdev.c | 859 ++++++++++++++++++++++++++++++++++
1 file changed, 859 insertions(+)
create mode 100644 drivers/fpga/xrt/lib/subdev.c

diff --git a/drivers/fpga/xrt/lib/subdev.c b/drivers/fpga/xrt/lib/subdev.c
new file mode 100644
index 000000000000..350f67d5eb1e
--- /dev/null
+++ b/drivers/fpga/xrt/lib/subdev.c
@@ -0,0 +1,859 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ * Cheng Zhen <maxz@xxxxxxxxxx>
+ */
+
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include "xleaf.h"
+#include "subdev_pool.h"
+#include "lib-drv.h"
+#include "metadata.h"
+
+extern struct bus_type xrt_bus_type;
+
+#define IS_ROOT_DEV(dev) ((dev)->bus != &xrt_bus_type)
+#define XRT_HOLDER_BUF_SZ 1024
+
+static inline struct device *find_root(struct xrt_device *xdev)
+{
+ struct device *d = DEV(xdev);
+
+ while (!IS_ROOT_DEV(d))
+ d = d->parent;
+ return d;
+}
+
+/*
+ * It represents a holder of a subdev. One holder can repeatedly hold a subdev
+ * as long as there is a unhold corresponding to a hold.
+ */
+struct xrt_subdev_holder {
+ struct list_head xsh_holder_list;
+ struct device *xsh_holder;
+ int xsh_count;
+ struct kref xsh_kref;
+};
+
+/*
+ * It represents a specific instance of platform driver for a subdev, which
+ * provides services to its clients (another subdev driver or root driver).
+ */
+struct xrt_subdev {
+ struct list_head xs_dev_list;
+ struct list_head xs_holder_list;
+ enum xrt_subdev_id xs_id; /* type of subdev */
+ struct xrt_device *xs_xdev;
+ struct completion xs_holder_comp;
+};
+
+static struct xrt_subdev *xrt_subdev_alloc(void)
+{
+ struct xrt_subdev *sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
+
+ if (!sdev)
+ return NULL;
+
+ INIT_LIST_HEAD(&sdev->xs_dev_list);
+ INIT_LIST_HEAD(&sdev->xs_holder_list);
+ init_completion(&sdev->xs_holder_comp);
+ return sdev;
+}
+
+int xrt_subdev_root_request(struct xrt_device *self, u32 cmd, void *arg)
+{
+ struct device *dev = DEV(self);
+ struct xrt_subdev_platdata *pdata = DEV_PDATA(self);
+
+ if (!pdata->xsp_root_cb) {
+ dev_err(dev, "invalid root callback");
+ return -EINVAL;
+ }
+ return (*pdata->xsp_root_cb)(dev->parent, pdata->xsp_root_cb_arg, cmd, arg);
+}
+
+/*
+ * Subdev common sysfs nodes.
+ */
+static ssize_t holders_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ ssize_t len;
+ struct xrt_device *xdev = to_xrt_dev(dev);
+ struct xrt_root_get_holders holders = { xdev, buf, XRT_HOLDER_BUF_SZ };
+
+ len = xrt_subdev_root_request(xdev, XRT_ROOT_GET_LEAF_HOLDERS, &holders);
+ if (len >= holders.xpigh_holder_buf_len)
+ return len;
+ buf[len] = '\n';
+ return len + 1;
+}
+static DEVICE_ATTR_RO(holders);
+
+static struct attribute *xrt_subdev_attrs[] = {
+ &dev_attr_holders.attr,
+ NULL,
+};
+
+static ssize_t metadata_output(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr, char *buf, loff_t off, size_t count)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct xrt_device *xdev = to_xrt_dev(dev);
+ struct xrt_subdev_platdata *pdata = DEV_PDATA(xdev);
+ unsigned char *blob;
+ unsigned long size;
+ ssize_t ret = 0;
+
+ blob = pdata->xsp_dtb;
+ size = xrt_md_size(dev, blob);
+ if (size == XRT_MD_INVALID_LENGTH) {
+ ret = -EINVAL;
+ goto failed;
+ }
+
+ if (off >= size) {
+ dev_dbg(dev, "offset (%lld) beyond total size: %ld\n", off, size);
+ goto failed;
+ }
+
+ if (off + count > size) {
+ dev_dbg(dev, "count (%ld) beyond left bytes: %lld\n",
+ (unsigned long)count, size - off);
+ count = size - off;
+ }
+ memcpy(buf, blob + off, count);
+
+ ret = count;
+failed:
+ return ret;
+}
+
+static struct bin_attribute meta_data_attr = {
+ .attr = {
+ .name = "metadata",
+ .mode = 0400
+ },
+ .read = metadata_output,
+ .size = 0
+};
+
+static struct bin_attribute *xrt_subdev_bin_attrs[] = {
+ &meta_data_attr,
+ NULL,
+};
+
+static const struct attribute_group xrt_subdev_attrgroup = {
+ .attrs = xrt_subdev_attrs,
+ .bin_attrs = xrt_subdev_bin_attrs,
+};
+
+/*
+ * Given the device metadata, parse it to get IO ranges and construct
+ * resource array.
+ */
+static int
+xrt_subdev_getres(struct device *parent, enum xrt_subdev_id id,
+ char *dtb, struct resource **res, int *res_num)
+{
+ struct xrt_subdev_platdata *pdata;
+ struct resource *pci_res = NULL;
+ const __be64 *bar_range;
+ const __be32 *bar_idx;
+ char *ep_name = NULL, *compat = NULL;
+ uint bar;
+ int count1 = 0, count2 = 0, ret;
+
+ if (!dtb)
+ return -EINVAL;
+
+ pdata = DEV_PDATA(to_xrt_dev(parent));
+
+ /* go through metadata and count endpoints in it */
+ xrt_md_get_next_endpoint(parent, dtb, NULL, NULL, &ep_name, &compat);
+ while (ep_name) {
+ ret = xrt_md_get_prop(parent, dtb, ep_name, compat,
+ XRT_MD_PROP_IO_OFFSET, (const void **)&bar_range, NULL);
+ if (!ret)
+ count1++;
+ xrt_md_get_next_endpoint(parent, dtb, ep_name, compat, &ep_name, &compat);
+ }
+ if (!count1)
+ return 0;
+
+ /* allocate resource array for all endpoints been found in metadata */
+ *res = vzalloc(sizeof(**res) * count1);
+
+ /* go through all endpoints again and get IO range for each endpoint */
+ ep_name = NULL;
+ xrt_md_get_next_endpoint(parent, dtb, NULL, NULL, &ep_name, &compat);
+ while (ep_name) {
+ ret = xrt_md_get_prop(parent, dtb, ep_name, compat,
+ XRT_MD_PROP_IO_OFFSET, (const void **)&bar_range, NULL);
+ if (ret)
+ continue;
+ xrt_md_get_prop(parent, dtb, ep_name, compat,
+ XRT_MD_PROP_BAR_IDX, (const void **)&bar_idx, NULL);
+ bar = bar_idx ? be32_to_cpu(*bar_idx) : 0;
+ xleaf_get_root_res(to_xrt_dev(parent), bar, &pci_res);
+ if (!pci_res) {
+ dev_err(parent, "Invalid bar defined %d", bar);
+ ret = -EINVAL;
+ goto failed;
+ }
+ (*res)[count2].start = pci_res->start + be64_to_cpu(bar_range[0]);
+ (*res)[count2].end = pci_res->start + be64_to_cpu(bar_range[0]) +
+ be64_to_cpu(bar_range[1]) - 1;
+ (*res)[count2].flags = IORESOURCE_MEM;
+ /* check if there is conflicted resource */
+ ret = request_resource(pci_res, *res + count2);
+ if (ret) {
+ dev_err(parent, "Conflict resource %pR\n", *res + count2);
+ goto failed;
+ }
+ release_resource(*res + count2);
+
+ (*res)[count2].parent = pci_res;
+
+ xrt_md_find_endpoint(parent, pdata->xsp_dtb, ep_name,
+ compat, &(*res)[count2].name);
+
+ count2++;
+ xrt_md_get_next_endpoint(parent, dtb, ep_name, compat, &ep_name, &compat);
+ }
+
+ WARN_ON(count1 != count2);
+ *res_num = count2;
+
+ return 0;
+
+failed:
+ vfree(*res);
+ *res_num = 0;
+ *res = NULL;
+ return ret;
+}
+
+static inline enum xrt_dev_file_mode
+xleaf_devnode_mode(struct xrt_device *xdev)
+{
+ return DEV_FILE_OPS(xdev)->xsf_mode;
+}
+
+static bool xrt_subdev_cdev_auto_creation(struct xrt_device *xdev)
+{
+ enum xrt_dev_file_mode mode = xleaf_devnode_mode(xdev);
+
+ if (!xleaf_devnode_enabled(xdev))
+ return false;
+
+ return (mode == XRT_DEV_FILE_DEFAULT || mode == XRT_DEV_FILE_MULTI_INST);
+}
+
+static struct xrt_subdev *
+xrt_subdev_create(struct device *parent, enum xrt_subdev_id id,
+ xrt_subdev_root_cb_t pcb, void *pcb_arg, char *dtb)
+{
+ struct xrt_subdev_platdata *pdata = NULL;
+ struct xrt_subdev *sdev = NULL;
+ struct xrt_device *xdev = NULL;
+ struct resource *res = NULL;
+ unsigned long dtb_len = 0;
+ bool dtb_alloced = false;
+ int res_num = 0;
+ size_t pdata_sz;
+ int ret;
+
+ sdev = xrt_subdev_alloc();
+ if (!sdev) {
+ dev_err(parent, "failed to alloc subdev for ID %d", id);
+ return NULL;
+ }
+ sdev->xs_id = id;
+
+ if (!dtb) {
+ ret = xrt_md_create(parent, &dtb);
+ if (ret) {
+ dev_err(parent, "can't create empty dtb: %d", ret);
+ goto fail;
+ }
+ dtb_alloced = true;
+ }
+ xrt_md_pack(parent, dtb);
+ dtb_len = xrt_md_size(parent, dtb);
+ if (dtb_len == XRT_MD_INVALID_LENGTH) {
+ dev_err(parent, "invalid metadata len %ld", dtb_len);
+ goto fail1;
+ }
+ pdata_sz = sizeof(struct xrt_subdev_platdata) + dtb_len;
+
+ /* Prepare platform data passed to subdev. */
+ pdata = vzalloc(pdata_sz);
+ if (!pdata)
+ goto fail1;
+
+ pdata->xsp_root_cb = pcb;
+ pdata->xsp_root_cb_arg = pcb_arg;
+ memcpy(pdata->xsp_dtb, dtb, dtb_len);
+ if (id == XRT_SUBDEV_GRP) {
+ /* Group can only be created by root driver. */
+ pdata->xsp_root_name = dev_name(parent);
+ } else {
+ struct xrt_device *grp = to_xrt_dev(parent);
+
+ /* Leaf can only be created by group driver. */
+ WARN_ON(to_xrt_drv(parent->driver)->subdev_id != XRT_SUBDEV_GRP);
+ pdata->xsp_root_name = DEV_PDATA(grp)->xsp_root_name;
+ }
+
+ /* Create subdev. */
+ if (id != XRT_SUBDEV_GRP) {
+ int rc = xrt_subdev_getres(parent, id, dtb, &res, &res_num);
+
+ if (rc) {
+ dev_err(parent, "failed to get resource for %s: %d",
+ xrt_drv_name(id), rc);
+ goto fail2;
+ }
+ }
+ xdev = xrt_device_register(parent, id, res, res_num, pdata, pdata_sz);
+ vfree(res);
+ if (!xdev) {
+ dev_err(parent, "failed to create subdev for %s", xrt_drv_name(id));
+ goto fail2;
+ }
+ sdev->xs_xdev = xdev;
+
+ if (device_attach(DEV(xdev)) != 1) {
+ xrt_err(xdev, "failed to attach");
+ goto fail3;
+ }
+
+ if (sysfs_create_group(&DEV(xdev)->kobj, &xrt_subdev_attrgroup))
+ xrt_err(xdev, "failed to create sysfs group");
+
+ /*
+ * Create sysfs sym link under root for leaves
+ * under random groups for easy access to them.
+ */
+ if (id != XRT_SUBDEV_GRP) {
+ if (sysfs_create_link(&find_root(xdev)->kobj,
+ &DEV(xdev)->kobj, dev_name(DEV(xdev)))) {
+ xrt_err(xdev, "failed to create sysfs link");
+ }
+ }
+
+ /* All done, ready to handle req thru cdev. */
+ if (xrt_subdev_cdev_auto_creation(xdev))
+ xleaf_devnode_create(xdev, DEV_FILE_OPS(xdev)->xsf_dev_name, NULL);
+
+ vfree(pdata);
+ return sdev;
+
+fail3:
+ xrt_device_unregister(sdev->xs_xdev);
+fail2:
+ vfree(pdata);
+fail1:
+ if (dtb_alloced)
+ vfree(dtb);
+fail:
+ kfree(sdev);
+ return NULL;
+}
+
+static void xrt_subdev_destroy(struct xrt_subdev *sdev)
+{
+ struct xrt_device *xdev = sdev->xs_xdev;
+ struct device *dev = DEV(xdev);
+
+ /* Take down the device node */
+ if (xrt_subdev_cdev_auto_creation(xdev))
+ xleaf_devnode_destroy(xdev);
+ if (sdev->xs_id != XRT_SUBDEV_GRP)
+ sysfs_remove_link(&find_root(xdev)->kobj, dev_name(dev));
+ sysfs_remove_group(&dev->kobj, &xrt_subdev_attrgroup);
+ xrt_device_unregister(xdev);
+ kfree(sdev);
+}
+
+struct xrt_device *
+xleaf_get_leaf(struct xrt_device *xdev, xrt_subdev_match_t match_cb, void *match_arg)
+{
+ int rc;
+ struct xrt_root_get_leaf get_leaf = {
+ xdev, match_cb, match_arg, };
+
+ rc = xrt_subdev_root_request(xdev, XRT_ROOT_GET_LEAF, &get_leaf);
+ if (rc)
+ return NULL;
+ return get_leaf.xpigl_tgt_xdev;
+}
+EXPORT_SYMBOL_GPL(xleaf_get_leaf);
+
+bool xleaf_has_endpoint(struct xrt_device *xdev, const char *endpoint_name)
+{
+ struct resource *res;
+ int i = 0;
+
+ do {
+ res = xrt_get_resource(xdev, IORESOURCE_MEM, i);
+ if (res && !strncmp(res->name, endpoint_name, strlen(res->name) + 1))
+ return true;
+ ++i;
+ } while (res);
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(xleaf_has_endpoint);
+
+int xleaf_put_leaf(struct xrt_device *xdev, struct xrt_device *leaf)
+{
+ struct xrt_root_put_leaf put_leaf = { xdev, leaf };
+
+ return xrt_subdev_root_request(xdev, XRT_ROOT_PUT_LEAF, &put_leaf);
+}
+EXPORT_SYMBOL_GPL(xleaf_put_leaf);
+
+int xleaf_create_group(struct xrt_device *xdev, char *dtb)
+{
+ return xrt_subdev_root_request(xdev, XRT_ROOT_CREATE_GROUP, dtb);
+}
+EXPORT_SYMBOL_GPL(xleaf_create_group);
+
+int xleaf_destroy_group(struct xrt_device *xdev, int instance)
+{
+ return xrt_subdev_root_request(xdev, XRT_ROOT_REMOVE_GROUP, (void *)(uintptr_t)instance);
+}
+EXPORT_SYMBOL_GPL(xleaf_destroy_group);
+
+int xleaf_wait_for_group_bringup(struct xrt_device *xdev)
+{
+ return xrt_subdev_root_request(xdev, XRT_ROOT_WAIT_GROUP_BRINGUP, NULL);
+}
+EXPORT_SYMBOL_GPL(xleaf_wait_for_group_bringup);
+
+static ssize_t
+xrt_subdev_get_holders(struct xrt_subdev *sdev, char *buf, size_t len)
+{
+ const struct list_head *ptr;
+ struct xrt_subdev_holder *h;
+ ssize_t n = 0;
+
+ list_for_each(ptr, &sdev->xs_holder_list) {
+ h = list_entry(ptr, struct xrt_subdev_holder, xsh_holder_list);
+ n += snprintf(buf + n, len - n, "%s:%d ",
+ dev_name(h->xsh_holder), kref_read(&h->xsh_kref));
+ /* Truncation is fine here. Buffer content is only for debugging. */
+ if (n >= (len - 1))
+ break;
+ }
+ return n;
+}
+
+void xrt_subdev_pool_init(struct device *dev, struct xrt_subdev_pool *spool)
+{
+ INIT_LIST_HEAD(&spool->xsp_dev_list);
+ spool->xsp_owner = dev;
+ mutex_init(&spool->xsp_lock);
+ spool->xsp_closing = false;
+}
+
+static void xrt_subdev_free_holder(struct xrt_subdev_holder *holder)
+{
+ list_del(&holder->xsh_holder_list);
+ vfree(holder);
+}
+
+static void xrt_subdev_pool_wait_for_holders(struct xrt_subdev_pool *spool, struct xrt_subdev *sdev)
+{
+ const struct list_head *ptr, *next;
+ char holders[128];
+ struct xrt_subdev_holder *holder;
+ struct mutex *lk = &spool->xsp_lock;
+
+ while (!list_empty(&sdev->xs_holder_list)) {
+ int rc;
+
+ /* It's most likely a bug if we ever enters this loop. */
+ xrt_subdev_get_holders(sdev, holders, sizeof(holders));
+ xrt_err(sdev->xs_xdev, "awaits holders: %s", holders);
+ mutex_unlock(lk);
+ rc = wait_for_completion_killable(&sdev->xs_holder_comp);
+ mutex_lock(lk);
+ if (rc == -ERESTARTSYS) {
+ xrt_err(sdev->xs_xdev, "give up on waiting for holders, clean up now");
+ list_for_each_safe(ptr, next, &sdev->xs_holder_list) {
+ holder = list_entry(ptr, struct xrt_subdev_holder, xsh_holder_list);
+ xrt_subdev_free_holder(holder);
+ }
+ }
+ }
+}
+
+void xrt_subdev_pool_fini(struct xrt_subdev_pool *spool)
+{
+ struct list_head *dl = &spool->xsp_dev_list;
+ struct mutex *lk = &spool->xsp_lock;
+
+ mutex_lock(lk);
+ if (spool->xsp_closing) {
+ mutex_unlock(lk);
+ return;
+ }
+ spool->xsp_closing = true;
+ mutex_unlock(lk);
+
+ /* Remove subdev in the reverse order of added. */
+ while (!list_empty(dl)) {
+ struct xrt_subdev *sdev = list_first_entry(dl, struct xrt_subdev, xs_dev_list);
+
+ xrt_subdev_pool_wait_for_holders(spool, sdev);
+ list_del(&sdev->xs_dev_list);
+ xrt_subdev_destroy(sdev);
+ }
+}
+
+static struct xrt_subdev_holder *xrt_subdev_find_holder(struct xrt_subdev *sdev,
+ struct device *holder_dev)
+{
+ struct list_head *hl = &sdev->xs_holder_list;
+ struct xrt_subdev_holder *holder;
+ const struct list_head *ptr;
+
+ list_for_each(ptr, hl) {
+ holder = list_entry(ptr, struct xrt_subdev_holder, xsh_holder_list);
+ if (holder->xsh_holder == holder_dev)
+ return holder;
+ }
+ return NULL;
+}
+
+static int xrt_subdev_hold(struct xrt_subdev *sdev, struct device *holder_dev)
+{
+ struct xrt_subdev_holder *holder = xrt_subdev_find_holder(sdev, holder_dev);
+ struct list_head *hl = &sdev->xs_holder_list;
+
+ if (!holder) {
+ holder = vzalloc(sizeof(*holder));
+ if (!holder)
+ return -ENOMEM;
+ holder->xsh_holder = holder_dev;
+ kref_init(&holder->xsh_kref);
+ list_add_tail(&holder->xsh_holder_list, hl);
+ } else {
+ kref_get(&holder->xsh_kref);
+ }
+
+ return 0;
+}
+
+static void xrt_subdev_free_holder_kref(struct kref *kref)
+{
+ struct xrt_subdev_holder *holder = container_of(kref, struct xrt_subdev_holder, xsh_kref);
+
+ xrt_subdev_free_holder(holder);
+}
+
+static int
+xrt_subdev_release(struct xrt_subdev *sdev, struct device *holder_dev)
+{
+ struct xrt_subdev_holder *holder = xrt_subdev_find_holder(sdev, holder_dev);
+ struct list_head *hl = &sdev->xs_holder_list;
+
+ if (!holder) {
+ dev_err(holder_dev, "can't release, %s did not hold %s",
+ dev_name(holder_dev), dev_name(DEV(sdev->xs_xdev)));
+ return -EINVAL;
+ }
+ kref_put(&holder->xsh_kref, xrt_subdev_free_holder_kref);
+
+ /* kref_put above may remove holder from list. */
+ if (list_empty(hl))
+ complete(&sdev->xs_holder_comp);
+ return 0;
+}
+
+int xrt_subdev_pool_add(struct xrt_subdev_pool *spool, enum xrt_subdev_id id,
+ xrt_subdev_root_cb_t pcb, void *pcb_arg, char *dtb)
+{
+ struct mutex *lk = &spool->xsp_lock;
+ struct list_head *dl = &spool->xsp_dev_list;
+ struct xrt_subdev *sdev;
+ int ret = 0;
+
+ sdev = xrt_subdev_create(spool->xsp_owner, id, pcb, pcb_arg, dtb);
+ if (sdev) {
+ mutex_lock(lk);
+ if (spool->xsp_closing) {
+ /* No new subdev when pool is going away. */
+ xrt_err(sdev->xs_xdev, "pool is closing");
+ ret = -ENODEV;
+ } else {
+ list_add(&sdev->xs_dev_list, dl);
+ }
+ mutex_unlock(lk);
+ if (ret)
+ xrt_subdev_destroy(sdev);
+ } else {
+ ret = -EINVAL;
+ }
+
+ ret = ret ? ret : sdev->xs_xdev->instance;
+ return ret;
+}
+
+int xrt_subdev_pool_del(struct xrt_subdev_pool *spool, enum xrt_subdev_id id, int instance)
+{
+ const struct list_head *ptr;
+ struct mutex *lk = &spool->xsp_lock;
+ struct list_head *dl = &spool->xsp_dev_list;
+ struct xrt_subdev *sdev;
+ int ret = -ENOENT;
+
+ mutex_lock(lk);
+ if (spool->xsp_closing) {
+ /* Pool is going away, all subdevs will be gone. */
+ mutex_unlock(lk);
+ return 0;
+ }
+ list_for_each(ptr, dl) {
+ sdev = list_entry(ptr, struct xrt_subdev, xs_dev_list);
+ if (sdev->xs_id != id || sdev->xs_xdev->instance != instance)
+ continue;
+ xrt_subdev_pool_wait_for_holders(spool, sdev);
+ list_del(&sdev->xs_dev_list);
+ ret = 0;
+ break;
+ }
+ mutex_unlock(lk);
+ if (ret)
+ return ret;
+
+ xrt_subdev_destroy(sdev);
+ return 0;
+}
+
+static int xrt_subdev_pool_get_impl(struct xrt_subdev_pool *spool, xrt_subdev_match_t match,
+ void *arg, struct device *holder_dev, struct xrt_subdev **sdevp)
+{
+ struct xrt_device *xdev = (struct xrt_device *)arg;
+ struct list_head *dl = &spool->xsp_dev_list;
+ struct mutex *lk = &spool->xsp_lock;
+ struct xrt_subdev *sdev = NULL;
+ const struct list_head *ptr;
+ struct xrt_subdev *d = NULL;
+ int ret = -ENOENT;
+
+ mutex_lock(lk);
+
+ if (!xdev) {
+ if (match == XRT_SUBDEV_MATCH_PREV) {
+ sdev = list_empty(dl) ? NULL :
+ list_last_entry(dl, struct xrt_subdev, xs_dev_list);
+ } else if (match == XRT_SUBDEV_MATCH_NEXT) {
+ sdev = list_first_entry_or_null(dl, struct xrt_subdev, xs_dev_list);
+ }
+ }
+
+ list_for_each(ptr, dl) {
+ d = list_entry(ptr, struct xrt_subdev, xs_dev_list);
+ if (match == XRT_SUBDEV_MATCH_PREV || match == XRT_SUBDEV_MATCH_NEXT) {
+ if (d->xs_xdev != xdev)
+ continue;
+ } else {
+ if (!match(d->xs_id, d->xs_xdev, arg))
+ continue;
+ }
+
+ if (match == XRT_SUBDEV_MATCH_PREV)
+ sdev = !list_is_first(ptr, dl) ? list_prev_entry(d, xs_dev_list) : NULL;
+ else if (match == XRT_SUBDEV_MATCH_NEXT)
+ sdev = !list_is_last(ptr, dl) ? list_next_entry(d, xs_dev_list) : NULL;
+ else
+ sdev = d;
+ }
+
+ if (sdev)
+ ret = xrt_subdev_hold(sdev, holder_dev);
+
+ mutex_unlock(lk);
+
+ if (!ret)
+ *sdevp = sdev;
+ return ret;
+}
+
+int xrt_subdev_pool_get(struct xrt_subdev_pool *spool, xrt_subdev_match_t match, void *arg,
+ struct device *holder_dev, struct xrt_device **xdevp)
+{
+ int rc;
+ struct xrt_subdev *sdev;
+
+ rc = xrt_subdev_pool_get_impl(spool, match, arg, holder_dev, &sdev);
+ if (rc) {
+ if (rc != -ENOENT)
+ dev_err(holder_dev, "failed to hold device: %d", rc);
+ return rc;
+ }
+
+ if (!IS_ROOT_DEV(holder_dev)) {
+ xrt_dbg(to_xrt_dev(holder_dev), "%s <<==== %s",
+ dev_name(holder_dev), dev_name(DEV(sdev->xs_xdev)));
+ }
+
+ *xdevp = sdev->xs_xdev;
+ return 0;
+}
+
+static int xrt_subdev_pool_put_impl(struct xrt_subdev_pool *spool, struct xrt_device *xdev,
+ struct device *holder_dev)
+{
+ const struct list_head *ptr;
+ struct mutex *lk = &spool->xsp_lock;
+ struct list_head *dl = &spool->xsp_dev_list;
+ struct xrt_subdev *sdev;
+ int ret = -ENOENT;
+
+ mutex_lock(lk);
+ list_for_each(ptr, dl) {
+ sdev = list_entry(ptr, struct xrt_subdev, xs_dev_list);
+ if (sdev->xs_xdev != xdev)
+ continue;
+ ret = xrt_subdev_release(sdev, holder_dev);
+ break;
+ }
+ mutex_unlock(lk);
+
+ return ret;
+}
+
+int xrt_subdev_pool_put(struct xrt_subdev_pool *spool, struct xrt_device *xdev,
+ struct device *holder_dev)
+{
+ int ret = xrt_subdev_pool_put_impl(spool, xdev, holder_dev);
+
+ if (ret)
+ return ret;
+
+ if (!IS_ROOT_DEV(holder_dev)) {
+ xrt_dbg(to_xrt_dev(holder_dev), "%s <<==X== %s",
+ dev_name(holder_dev), dev_name(DEV(xdev)));
+ }
+ return 0;
+}
+
+void xrt_subdev_pool_trigger_event(struct xrt_subdev_pool *spool, enum xrt_events e)
+{
+ struct xrt_device *tgt = NULL;
+ struct xrt_subdev *sdev = NULL;
+ struct xrt_event evt;
+
+ while (!xrt_subdev_pool_get_impl(spool, XRT_SUBDEV_MATCH_NEXT,
+ tgt, spool->xsp_owner, &sdev)) {
+ tgt = sdev->xs_xdev;
+ evt.xe_evt = e;
+ evt.xe_subdev.xevt_subdev_id = sdev->xs_id;
+ evt.xe_subdev.xevt_subdev_instance = tgt->instance;
+ xrt_subdev_root_request(tgt, XRT_ROOT_EVENT_SYNC, &evt);
+ xrt_subdev_pool_put_impl(spool, tgt, spool->xsp_owner);
+ }
+}
+
+void xrt_subdev_pool_handle_event(struct xrt_subdev_pool *spool, struct xrt_event *evt)
+{
+ struct xrt_device *tgt = NULL;
+ struct xrt_subdev *sdev = NULL;
+
+ while (!xrt_subdev_pool_get_impl(spool, XRT_SUBDEV_MATCH_NEXT,
+ tgt, spool->xsp_owner, &sdev)) {
+ tgt = sdev->xs_xdev;
+ xleaf_call(tgt, XRT_XLEAF_EVENT, evt);
+ xrt_subdev_pool_put_impl(spool, tgt, spool->xsp_owner);
+ }
+}
+
+ssize_t xrt_subdev_pool_get_holders(struct xrt_subdev_pool *spool,
+ struct xrt_device *xdev, char *buf, size_t len)
+{
+ const struct list_head *ptr;
+ struct mutex *lk = &spool->xsp_lock;
+ struct list_head *dl = &spool->xsp_dev_list;
+ struct xrt_subdev *sdev;
+ ssize_t ret = 0;
+
+ mutex_lock(lk);
+ list_for_each(ptr, dl) {
+ sdev = list_entry(ptr, struct xrt_subdev, xs_dev_list);
+ if (sdev->xs_xdev != xdev)
+ continue;
+ ret = xrt_subdev_get_holders(sdev, buf, len);
+ break;
+ }
+ mutex_unlock(lk);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(xrt_subdev_pool_get_holders);
+
+int xleaf_broadcast_event(struct xrt_device *xdev, enum xrt_events evt, bool async)
+{
+ struct xrt_event e = { evt, };
+ enum xrt_root_cmd cmd = async ? XRT_ROOT_EVENT_ASYNC : XRT_ROOT_EVENT_SYNC;
+
+ WARN_ON(evt == XRT_EVENT_POST_CREATION || evt == XRT_EVENT_PRE_REMOVAL);
+ return xrt_subdev_root_request(xdev, cmd, &e);
+}
+EXPORT_SYMBOL_GPL(xleaf_broadcast_event);
+
+void xleaf_hot_reset(struct xrt_device *xdev)
+{
+ xrt_subdev_root_request(xdev, XRT_ROOT_HOT_RESET, NULL);
+}
+EXPORT_SYMBOL_GPL(xleaf_hot_reset);
+
+void xleaf_get_root_res(struct xrt_device *xdev, u32 region_id, struct resource **res)
+{
+ struct xrt_root_get_res arg = { 0 };
+
+ arg.xpigr_region_id = region_id;
+ xrt_subdev_root_request(xdev, XRT_ROOT_GET_RESOURCE, &arg);
+ *res = arg.xpigr_res;
+}
+
+void xleaf_get_root_id(struct xrt_device *xdev, unsigned short *vendor, unsigned short *device,
+ unsigned short *subvendor, unsigned short *subdevice)
+{
+ struct xrt_root_get_id id = { 0 };
+
+ WARN_ON(!vendor && !device && !subvendor && !subdevice);
+
+ xrt_subdev_root_request(xdev, XRT_ROOT_GET_ID, (void *)&id);
+ if (vendor)
+ *vendor = id.xpigi_vendor_id;
+ if (device)
+ *device = id.xpigi_device_id;
+ if (subvendor)
+ *subvendor = id.xpigi_sub_vendor_id;
+ if (subdevice)
+ *subdevice = id.xpigi_sub_device_id;
+}
+
+struct device *xleaf_register_hwmon(struct xrt_device *xdev, const char *name, void *drvdata,
+ const struct attribute_group **grps)
+{
+ struct xrt_root_hwmon hm = { true, name, drvdata, grps, };
+
+ xrt_subdev_root_request(xdev, XRT_ROOT_HWMON, (void *)&hm);
+ return hm.xpih_hwmon_dev;
+}
+
+void xleaf_unregister_hwmon(struct xrt_device *xdev, struct device *hwmon)
+{
+ struct xrt_root_hwmon hm = { false, };
+
+ hm.xpih_hwmon_dev = hwmon;
+ xrt_subdev_root_request(xdev, XRT_ROOT_HWMON, (void *)&hm);
+}
--
2.27.0