diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-01-20 14:01:31 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-01-20 14:01:31 -0300 |
commit | b4b7ff4b08e691656c9d77c758fc355833128ac0 (patch) | |
tree | 82fcb00e6b918026dc9f2d1f05ed8eee83874cc0 /drivers/fpga/fpga-mgr.c | |
parent | 35acfa0fc609f2a2cd95cef4a6a9c3a5c38f1778 (diff) |
Linux-libre 4.4-gnupck-4.4-gnu
Diffstat (limited to 'drivers/fpga/fpga-mgr.c')
-rw-r--r-- | drivers/fpga/fpga-mgr.c | 375 |
1 files changed, 375 insertions, 0 deletions
diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c new file mode 100644 index 000000000..953dc9195 --- /dev/null +++ b/drivers/fpga/fpga-mgr.c @@ -0,0 +1,375 @@ +/* + * 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. This code assumes the caller got the + * mgr pointer from of_fpga_mgr_get() and checked that it is not an error code. + * + * 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; + + /* + * 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. This code assumes the caller got the mgr pointer + * from of_fpga_mgr_get() and checked that it is not an error code. + * + * 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; + + 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); + + release_firmware(fw); + + return ret; +} +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; + int ret = -ENODEV; + + 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); + if (!mgr) + goto err_dev; + + /* Get exclusive use of fpga manager */ + if (!mutex_trylock(&mgr->ref_mutex)) { + ret = -EBUSY; + goto err_dev; + } + + if (!try_module_get(dev->parent->driver->owner)) + goto err_ll_mod; + + return mgr; + +err_ll_mod: + mutex_unlock(&mgr->ref_mutex); +err_dev: + put_device(dev); + return ERR_PTR(ret); +} +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) +{ + module_put(mgr->dev.parent->driver->owner); + mutex_unlock(&mgr->ref_mutex); + put_device(&mgr->dev); +} +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; + 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); + + ret = dev_set_name(&mgr->dev, "fpga%d", id); + if (ret) + goto error_device; + + 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); |