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authorAlan Tull <atull@opensource.altera.com>2015-10-07 18:36:28 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-10-07 20:08:15 +0300
commit6a8c3be7ec8eb3c1197766f9245e0d65a4e5aff8 (patch)
tree311c3845b068f737086813b1231b1c3b695f0a1c /drivers/fpga
parentafb79e993a949d02895b912eacc86ab0e416b6fd (diff)
downloadlinux-6a8c3be7ec8eb3c1197766f9245e0d65a4e5aff8.tar.xz
add FPGA manager core
API to support programming FPGA's. The following functions are exported as GPL: * fpga_mgr_buf_load Load fpga from image in buffer * fpga_mgr_firmware_load Request firmware and load it to the FPGA. * fpga_mgr_register * fpga_mgr_unregister FPGA device drivers can be added by calling fpga_mgr_register() to register a set of fpga_manager_ops to do device specific stuff. * of_fpga_mgr_get * fpga_mgr_put Get/put a reference to a fpga manager. The following sysfs files are created: * /sys/class/fpga_manager/<fpga>/name Name of low level driver. * /sys/class/fpga_manager/<fpga>/state State of fpga manager Signed-off-by: Alan Tull <atull@opensource.altera.com> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/fpga')
-rw-r--r--drivers/fpga/Kconfig14
-rw-r--r--drivers/fpga/Makefile8
-rw-r--r--drivers/fpga/fpga-mgr.c382
3 files changed, 404 insertions, 0 deletions
diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
new file mode 100644
index 000000000000..f1f1f6df54d3
--- /dev/null
+++ b/drivers/fpga/Kconfig
@@ -0,0 +1,14 @@
+#
+# FPGA framework configuration
+#
+
+menu "FPGA Configuration Support"
+
+config FPGA
+ tristate "FPGA Configuration Framework"
+ help
+ Say Y here if you want support for configuring FPGAs from the
+ kernel. The FPGA framework adds a FPGA manager class and FPGA
+ manager drivers.
+
+endmenu
diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
new file mode 100644
index 000000000000..3313c5266795
--- /dev/null
+++ b/drivers/fpga/Makefile
@@ -0,0 +1,8 @@
+#
+# Makefile for the fpga framework and fpga manager drivers.
+#
+
+# Core FPGA Manager Framework
+obj-$(CONFIG_FPGA) += fpga-mgr.o
+
+# FPGA Manager Drivers
diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
new file mode 100644
index 000000000000..25261636687c
--- /dev/null
+++ b/drivers/fpga/fpga-mgr.c
@@ -0,0 +1,382 @@
+/*
+ * FPGA Manager Core
+ *
+ * Copyright (C) 2013-2015 Altera Corporation
+ *
+ * With code from the mailing list:
+ * Copyright (C) 2013 Xilinx, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/firmware.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/idr.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+
+static DEFINE_IDA(fpga_mgr_ida);
+static struct class *fpga_mgr_class;
+
+/**
+ * fpga_mgr_buf_load - load fpga from image in buffer
+ * @mgr: fpga manager
+ * @flags: flags setting fpga confuration modes
+ * @buf: buffer contain fpga image
+ * @count: byte count of buf
+ *
+ * Step the low level fpga manager through the device-specific steps of getting
+ * an FPGA ready to be configured, writing the image to it, then doing whatever
+ * post-configuration steps necessary.
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+int fpga_mgr_buf_load(struct fpga_manager *mgr, u32 flags, const char *buf,
+ size_t count)
+{
+ struct device *dev = &mgr->dev;
+ int ret;
+
+ if (!mgr)
+ return -ENODEV;
+
+ /*
+ * Call the low level driver's write_init function. This will do the
+ * device-specific things to get the FPGA into the state where it is
+ * ready to receive an FPGA image.
+ */
+ mgr->state = FPGA_MGR_STATE_WRITE_INIT;
+ ret = mgr->mops->write_init(mgr, flags, buf, count);
+ if (ret) {
+ dev_err(dev, "Error preparing FPGA for writing\n");
+ mgr->state = FPGA_MGR_STATE_WRITE_INIT_ERR;
+ return ret;
+ }
+
+ /*
+ * Write the FPGA image to the FPGA.
+ */
+ mgr->state = FPGA_MGR_STATE_WRITE;
+ ret = mgr->mops->write(mgr, buf, count);
+ if (ret) {
+ dev_err(dev, "Error while writing image data to FPGA\n");
+ mgr->state = FPGA_MGR_STATE_WRITE_ERR;
+ return ret;
+ }
+
+ /*
+ * After all the FPGA image has been written, do the device specific
+ * steps to finish and set the FPGA into operating mode.
+ */
+ mgr->state = FPGA_MGR_STATE_WRITE_COMPLETE;
+ ret = mgr->mops->write_complete(mgr, flags);
+ if (ret) {
+ dev_err(dev, "Error after writing image data to FPGA\n");
+ mgr->state = FPGA_MGR_STATE_WRITE_COMPLETE_ERR;
+ return ret;
+ }
+ mgr->state = FPGA_MGR_STATE_OPERATING;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_buf_load);
+
+/**
+ * fpga_mgr_firmware_load - request firmware and load to fpga
+ * @mgr: fpga manager
+ * @flags: flags setting fpga confuration modes
+ * @image_name: name of image file on the firmware search path
+ *
+ * Request an FPGA image using the firmware class, then write out to the FPGA.
+ * Update the state before each step to provide info on what step failed if
+ * there is a failure.
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+int fpga_mgr_firmware_load(struct fpga_manager *mgr, u32 flags,
+ const char *image_name)
+{
+ struct device *dev = &mgr->dev;
+ const struct firmware *fw;
+ int ret;
+
+ if (!mgr)
+ return -ENODEV;
+
+ dev_info(dev, "writing %s to %s\n", image_name, mgr->name);
+
+ mgr->state = FPGA_MGR_STATE_FIRMWARE_REQ;
+
+ ret = request_firmware(&fw, image_name, dev);
+ if (ret) {
+ mgr->state = FPGA_MGR_STATE_FIRMWARE_REQ_ERR;
+ dev_err(dev, "Error requesting firmware %s\n", image_name);
+ return ret;
+ }
+
+ ret = fpga_mgr_buf_load(mgr, flags, fw->data, fw->size);
+ if (ret)
+ return ret;
+
+ release_firmware(fw);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_firmware_load);
+
+static const char * const state_str[] = {
+ [FPGA_MGR_STATE_UNKNOWN] = "unknown",
+ [FPGA_MGR_STATE_POWER_OFF] = "power off",
+ [FPGA_MGR_STATE_POWER_UP] = "power up",
+ [FPGA_MGR_STATE_RESET] = "reset",
+
+ /* requesting FPGA image from firmware */
+ [FPGA_MGR_STATE_FIRMWARE_REQ] = "firmware request",
+ [FPGA_MGR_STATE_FIRMWARE_REQ_ERR] = "firmware request error",
+
+ /* Preparing FPGA to receive image */
+ [FPGA_MGR_STATE_WRITE_INIT] = "write init",
+ [FPGA_MGR_STATE_WRITE_INIT_ERR] = "write init error",
+
+ /* Writing image to FPGA */
+ [FPGA_MGR_STATE_WRITE] = "write",
+ [FPGA_MGR_STATE_WRITE_ERR] = "write error",
+
+ /* Finishing configuration after image has been written */
+ [FPGA_MGR_STATE_WRITE_COMPLETE] = "write complete",
+ [FPGA_MGR_STATE_WRITE_COMPLETE_ERR] = "write complete error",
+
+ /* FPGA reports to be in normal operating mode */
+ [FPGA_MGR_STATE_OPERATING] = "operating",
+};
+
+static ssize_t name_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct fpga_manager *mgr = to_fpga_manager(dev);
+
+ return sprintf(buf, "%s\n", mgr->name);
+}
+
+static ssize_t state_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct fpga_manager *mgr = to_fpga_manager(dev);
+
+ return sprintf(buf, "%s\n", state_str[mgr->state]);
+}
+
+static DEVICE_ATTR_RO(name);
+static DEVICE_ATTR_RO(state);
+
+static struct attribute *fpga_mgr_attrs[] = {
+ &dev_attr_name.attr,
+ &dev_attr_state.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(fpga_mgr);
+
+static int fpga_mgr_of_node_match(struct device *dev, const void *data)
+{
+ return dev->of_node == data;
+}
+
+/**
+ * of_fpga_mgr_get - get an exclusive reference to a fpga mgr
+ * @node: device node
+ *
+ * Given a device node, get an exclusive reference to a fpga mgr.
+ *
+ * Return: fpga manager struct or IS_ERR() condition containing error code.
+ */
+struct fpga_manager *of_fpga_mgr_get(struct device_node *node)
+{
+ struct fpga_manager *mgr;
+ struct device *dev;
+
+ if (!node)
+ return ERR_PTR(-EINVAL);
+
+ dev = class_find_device(fpga_mgr_class, NULL, node,
+ fpga_mgr_of_node_match);
+ if (!dev)
+ return ERR_PTR(-ENODEV);
+
+ mgr = to_fpga_manager(dev);
+ put_device(dev);
+ if (!mgr)
+ return ERR_PTR(-ENODEV);
+
+ /* Get exclusive use of fpga manager */
+ if (!mutex_trylock(&mgr->ref_mutex))
+ return ERR_PTR(-EBUSY);
+
+ if (!try_module_get(THIS_MODULE)) {
+ mutex_unlock(&mgr->ref_mutex);
+ return ERR_PTR(-ENODEV);
+ }
+
+ return mgr;
+}
+EXPORT_SYMBOL_GPL(of_fpga_mgr_get);
+
+/**
+ * fpga_mgr_put - release a reference to a fpga manager
+ * @mgr: fpga manager structure
+ */
+void fpga_mgr_put(struct fpga_manager *mgr)
+{
+ if (mgr) {
+ module_put(THIS_MODULE);
+ mutex_unlock(&mgr->ref_mutex);
+ }
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_put);
+
+/**
+ * fpga_mgr_register - register a low level fpga manager driver
+ * @dev: fpga manager device from pdev
+ * @name: fpga manager name
+ * @mops: pointer to structure of fpga manager ops
+ * @priv: fpga manager private data
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+int fpga_mgr_register(struct device *dev, const char *name,
+ const struct fpga_manager_ops *mops,
+ void *priv)
+{
+ struct fpga_manager *mgr;
+ const char *dt_label;
+ int id, ret;
+
+ if (!mops || !mops->write_init || !mops->write ||
+ !mops->write_complete || !mops->state) {
+ dev_err(dev, "Attempt to register without fpga_manager_ops\n");
+ return -EINVAL;
+ }
+
+ if (!name || !strlen(name)) {
+ dev_err(dev, "Attempt to register with no name!\n");
+ return -EINVAL;
+ }
+
+ mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
+ if (!mgr)
+ return -ENOMEM;
+
+ id = ida_simple_get(&fpga_mgr_ida, 0, 0, GFP_KERNEL);
+ if (id < 0) {
+ ret = id;
+ goto error_kfree;
+ }
+
+ mutex_init(&mgr->ref_mutex);
+
+ mgr->name = name;
+ mgr->mops = mops;
+ mgr->priv = priv;
+
+ /*
+ * Initialize framework state by requesting low level driver read state
+ * from device. FPGA may be in reset mode or may have been programmed
+ * by bootloader or EEPROM.
+ */
+ mgr->state = mgr->mops->state(mgr);
+
+ device_initialize(&mgr->dev);
+ mgr->dev.class = fpga_mgr_class;
+ mgr->dev.parent = dev;
+ mgr->dev.of_node = dev->of_node;
+ mgr->dev.id = id;
+ dev_set_drvdata(dev, mgr);
+
+ dt_label = of_get_property(mgr->dev.of_node, "label", NULL);
+ if (dt_label)
+ ret = dev_set_name(&mgr->dev, "%s", dt_label);
+ else
+ ret = dev_set_name(&mgr->dev, "fpga%d", id);
+
+ ret = device_add(&mgr->dev);
+ if (ret)
+ goto error_device;
+
+ dev_info(&mgr->dev, "%s registered\n", mgr->name);
+
+ return 0;
+
+error_device:
+ ida_simple_remove(&fpga_mgr_ida, id);
+error_kfree:
+ kfree(mgr);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_register);
+
+/**
+ * fpga_mgr_unregister - unregister a low level fpga manager driver
+ * @dev: fpga manager device from pdev
+ */
+void fpga_mgr_unregister(struct device *dev)
+{
+ struct fpga_manager *mgr = dev_get_drvdata(dev);
+
+ dev_info(&mgr->dev, "%s %s\n", __func__, mgr->name);
+
+ /*
+ * If the low level driver provides a method for putting fpga into
+ * a desired state upon unregister, do it.
+ */
+ if (mgr->mops->fpga_remove)
+ mgr->mops->fpga_remove(mgr);
+
+ device_unregister(&mgr->dev);
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_unregister);
+
+static void fpga_mgr_dev_release(struct device *dev)
+{
+ struct fpga_manager *mgr = to_fpga_manager(dev);
+
+ ida_simple_remove(&fpga_mgr_ida, mgr->dev.id);
+ kfree(mgr);
+}
+
+static int __init fpga_mgr_class_init(void)
+{
+ pr_info("FPGA manager framework\n");
+
+ fpga_mgr_class = class_create(THIS_MODULE, "fpga_manager");
+ if (IS_ERR(fpga_mgr_class))
+ return PTR_ERR(fpga_mgr_class);
+
+ fpga_mgr_class->dev_groups = fpga_mgr_groups;
+ fpga_mgr_class->dev_release = fpga_mgr_dev_release;
+
+ return 0;
+}
+
+static void __exit fpga_mgr_class_exit(void)
+{
+ class_destroy(fpga_mgr_class);
+ ida_destroy(&fpga_mgr_ida);
+}
+
+MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
+MODULE_DESCRIPTION("FPGA manager framework");
+MODULE_LICENSE("GPL v2");
+
+subsys_initcall(fpga_mgr_class_init);
+module_exit(fpga_mgr_class_exit);