[PATCH V3 XRT Alveo 05/18] fpga: xrt: group platform driver

[Lizhi Hou <lizhi.hou@xilinx.com>]

group driver that manages life cycle of a bunch of leaf driver instances
and bridges them with root.

Signed-off-by: Sonal Santan <sonal.santan@xilinx.com>
Signed-off-by: Max Zhen <max.zhen@xilinx.com>
Signed-off-by: Lizhi Hou <lizhih@xilinx.com>
---
 drivers/fpga/xrt/include/group.h |  27 ++++
 drivers/fpga/xrt/lib/group.c     | 265 +++++++++++++++++++++++++++++++
 2 files changed, 292 insertions(+)
 create mode 100644 drivers/fpga/xrt/include/group.h
 create mode 100644 drivers/fpga/xrt/lib/group.c

diff --git a/drivers/fpga/xrt/include/group.h b/drivers/fpga/xrt/include/group.h
new file mode 100644
index 000000000000..1874cdd5120d
--- /dev/null
+++ b/drivers/fpga/xrt/include/group.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Header file for Xilinx Runtime (XRT) driver
+ *
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ *	Cheng Zhen <maxz@xilinx.com>
+ */
+
+#ifndef _XRT_GROUP_H_
+#define _XRT_GROUP_H_
+
+#include "xleaf.h"
+
+/*
+ * Group driver IOCTL calls.
+ */
+enum xrt_group_ioctl_cmd {
+	XRT_GROUP_GET_LEAF = XRT_XLEAF_CUSTOM_BASE, /* See comments in xleaf.h */
+	XRT_GROUP_PUT_LEAF,
+	XRT_GROUP_INIT_CHILDREN,
+	XRT_GROUP_FINI_CHILDREN,
+	XRT_GROUP_TRIGGER_EVENT,
+};
+
+#endif	/* _XRT_GROUP_H_ */
diff --git a/drivers/fpga/xrt/lib/group.c b/drivers/fpga/xrt/lib/group.c
new file mode 100644
index 000000000000..6ba56eea479b
--- /dev/null
+++ b/drivers/fpga/xrt/lib/group.c
@@ -0,0 +1,265 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx Alveo FPGA Group Driver
+ *
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ *	Cheng Zhen <maxz@xilinx.com>
+ */
+
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+#include "xleaf.h"
+#include "subdev_pool.h"
+#include "group.h"
+#include "metadata.h"
+#include "main.h"
+
+#define XRT_GRP "xrt_group"
+
+struct xrt_group {
+	struct platform_device *pdev;
+	struct xrt_subdev_pool leaves;
+	bool leaves_created;
+	struct mutex lock; /* lock for group */
+};
+
+static int xrt_grp_root_cb(struct device *dev, void *parg,
+			   u32 cmd, void *arg)
+{
+	int rc;
+	struct platform_device *pdev =
+		container_of(dev, struct platform_device, dev);
+	struct xrt_group *xg = (struct xrt_group *)parg;
+
+	switch (cmd) {
+	case XRT_ROOT_GET_LEAF_HOLDERS: {
+		struct xrt_root_ioctl_get_holders *holders =
+			(struct xrt_root_ioctl_get_holders *)arg;
+		rc = xrt_subdev_pool_get_holders(&xg->leaves,
+						 holders->xpigh_pdev,
+						 holders->xpigh_holder_buf,
+						 holders->xpigh_holder_buf_len);
+		break;
+	}
+	default:
+		/* Forward parent call to root. */
+		rc = xrt_subdev_root_request(pdev, cmd, arg);
+		break;
+	}
+
+	return rc;
+}
+
+static int xrt_grp_create_leaves(struct xrt_group *xg)
+{
+	struct xrt_subdev_platdata *pdata = DEV_PDATA(xg->pdev);
+	enum xrt_subdev_id did;
+	struct xrt_subdev_endpoints *eps = NULL;
+	int ep_count = 0, i, ret = 0, failed = 0;
+	unsigned long mlen;
+	char *dtb, *grp_dtb = NULL;
+	const char *ep_name;
+
+	mutex_lock(&xg->lock);
+
+	if (xg->leaves_created) {
+		mutex_unlock(&xg->lock);
+		return -EEXIST;
+	}
+
+	xrt_info(xg->pdev, "bringing up leaves...");
+
+	/* Create all leaves based on dtb. */
+	if (!pdata)
+		goto bail;
+
+	mlen = xrt_md_size(DEV(xg->pdev), pdata->xsp_dtb);
+	if (mlen == XRT_MD_INVALID_LENGTH) {
+		xrt_err(xg->pdev, "invalid dtb, len %ld", mlen);
+		goto bail;
+	}
+
+	grp_dtb = vmalloc(mlen);
+	if (!grp_dtb)
+		goto bail;
+
+	memcpy(grp_dtb, pdata->xsp_dtb, mlen);
+	for (did = 0; did < XRT_SUBDEV_NUM;) {
+		eps = eps ? eps + 1 : xrt_drv_get_endpoints(did);
+		if (!eps || !eps->xse_names) {
+			did++;
+			eps = NULL;
+			continue;
+		}
+		ret = xrt_md_create(DEV(xg->pdev), &dtb);
+		if (ret) {
+			xrt_err(xg->pdev, "create md failed, drv %s",
+				xrt_drv_name(did));
+			failed++;
+			continue;
+		}
+		for (i = 0; eps->xse_names[i].ep_name ||
+		     eps->xse_names[i].regmap_name; i++) {
+			ep_name = (char *)eps->xse_names[i].ep_name;
+			if (!ep_name) {
+				xrt_md_get_compatible_endpoint(DEV(xg->pdev),
+							       grp_dtb,
+							       eps->xse_names[i].regmap_name,
+							       &ep_name);
+			}
+			if (!ep_name)
+				continue;
+
+			ret = xrt_md_copy_endpoint(DEV(xg->pdev),
+						   dtb, grp_dtb, ep_name,
+						   (char *)eps->xse_names[i].regmap_name,
+						   NULL);
+			if (ret)
+				continue;
+			xrt_md_del_endpoint(DEV(xg->pdev), grp_dtb, ep_name,
+					    (char *)eps->xse_names[i].regmap_name);
+			ep_count++;
+		}
+		if (ep_count >= eps->xse_min_ep) {
+			ret = xrt_subdev_pool_add(&xg->leaves, did,
+						  xrt_grp_root_cb, xg, dtb);
+			eps = NULL;
+			if (ret < 0) {
+				failed++;
+				xrt_err(xg->pdev, "failed to create %s: %d",
+					xrt_drv_name(did), ret);
+			}
+		} else if (ep_count > 0) {
+			xrt_md_copy_all_endpoints(DEV(xg->pdev), grp_dtb, dtb);
+		}
+		vfree(dtb);
+		ep_count = 0;
+	}
+
+	xg->leaves_created = true;
+
+bail:
+	vfree(grp_dtb);
+	mutex_unlock(&xg->lock);
+
+	return failed == 0 ? 0 : -ECHILD;
+}
+
+static void xrt_grp_remove_leaves(struct xrt_group *xg)
+{
+	mutex_lock(&xg->lock);
+
+	if (!xg->leaves_created) {
+		mutex_unlock(&xg->lock);
+		return;
+	}
+
+	xrt_info(xg->pdev, "tearing down leaves...");
+	xrt_subdev_pool_fini(&xg->leaves);
+	xg->leaves_created = false;
+
+	mutex_unlock(&xg->lock);
+}
+
+static int xrt_grp_probe(struct platform_device *pdev)
+{
+	struct xrt_group *xg;
+
+	xrt_info(pdev, "probing...");
+
+	xg = devm_kzalloc(&pdev->dev, sizeof(*xg), GFP_KERNEL);
+	if (!xg)
+		return -ENOMEM;
+
+	xg->pdev = pdev;
+	mutex_init(&xg->lock);
+	xrt_subdev_pool_init(DEV(pdev), &xg->leaves);
+	platform_set_drvdata(pdev, xg);
+
+	return 0;
+}
+
+static int xrt_grp_remove(struct platform_device *pdev)
+{
+	struct xrt_group *xg = platform_get_drvdata(pdev);
+
+	xrt_info(pdev, "leaving...");
+	xrt_grp_remove_leaves(xg);
+	return 0;
+}
+
+static int xrt_grp_ioctl(struct platform_device *pdev, u32 cmd, void *arg)
+{
+	int rc = 0;
+	struct xrt_group *xg = platform_get_drvdata(pdev);
+
+	switch (cmd) {
+	case XRT_XLEAF_EVENT:
+		/* Simply forward to every child. */
+		xrt_subdev_pool_handle_event(&xg->leaves,
+					     (struct xrt_event *)arg);
+		break;
+	case XRT_GROUP_GET_LEAF: {
+		struct xrt_root_ioctl_get_leaf *get_leaf =
+			(struct xrt_root_ioctl_get_leaf *)arg;
+
+		rc = xrt_subdev_pool_get(&xg->leaves, get_leaf->xpigl_match_cb,
+					 get_leaf->xpigl_match_arg,
+					 DEV(get_leaf->xpigl_pdev),
+					 &get_leaf->xpigl_leaf);
+		break;
+	}
+	case XRT_GROUP_PUT_LEAF: {
+		struct xrt_root_ioctl_put_leaf *put_leaf =
+			(struct xrt_root_ioctl_put_leaf *)arg;
+
+		rc = xrt_subdev_pool_put(&xg->leaves, put_leaf->xpipl_leaf,
+					 DEV(put_leaf->xpipl_pdev));
+		break;
+	}
+	case XRT_GROUP_INIT_CHILDREN:
+		rc = xrt_grp_create_leaves(xg);
+		break;
+	case XRT_GROUP_FINI_CHILDREN:
+		xrt_grp_remove_leaves(xg);
+		break;
+	case XRT_GROUP_TRIGGER_EVENT:
+		xrt_subdev_pool_trigger_event(&xg->leaves, (enum xrt_events)(uintptr_t)arg);
+		break;
+	default:
+		xrt_err(pdev, "unknown IOCTL cmd %d", cmd);
+		rc = -EINVAL;
+		break;
+	}
+	return rc;
+}
+
+static struct xrt_subdev_drvdata xrt_grp_data = {
+	.xsd_dev_ops = {
+		.xsd_ioctl = xrt_grp_ioctl,
+	},
+};
+
+static const struct platform_device_id xrt_grp_id_table[] = {
+	{ XRT_GRP, (kernel_ulong_t)&xrt_grp_data },
+	{ },
+};
+
+static struct platform_driver xrt_group_driver = {
+	.driver	= {
+		.name    = XRT_GRP,
+	},
+	.probe   = xrt_grp_probe,
+	.remove  = xrt_grp_remove,
+	.id_table = xrt_grp_id_table,
+};
+
+void group_leaf_init_fini(bool init)
+{
+	if (init)
+		xleaf_register_driver(XRT_SUBDEV_GRP, &xrt_group_driver, NULL);
+	else
+		xleaf_unregister_driver(XRT_SUBDEV_GRP);
+}
-- 
2.18.4