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Release 4.11 drivers/fpga/fpga-mgr.c

Directory: drivers/fpga
/*
 * 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>
#include <linux/scatterlist.h>
#include <linux/highmem.h>

static DEFINE_IDA(fpga_mgr_ida);

static struct class *fpga_mgr_class;

/*
 * 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. The low level driver only gets to see the first
 * initial_header_size bytes in the buffer.
 */

static int fpga_mgr_write_init_buf(struct fpga_manager *mgr, struct fpga_image_info *info, const char *buf, size_t count) { int ret; mgr->state = FPGA_MGR_STATE_WRITE_INIT; if (!mgr->mops->initial_header_size) ret = mgr->mops->write_init(mgr, info, NULL, 0); else ret = mgr->mops->write_init( mgr, info, buf, min(mgr->mops->initial_header_size, count)); if (ret) { dev_err(&mgr->dev, "Error preparing FPGA for writing\n"); mgr->state = FPGA_MGR_STATE_WRITE_INIT_ERR; return ret; } return 0; }

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static int fpga_mgr_write_init_sg(struct fpga_manager *mgr, struct fpga_image_info *info, struct sg_table *sgt) { struct sg_mapping_iter miter; size_t len; char *buf; int ret; if (!mgr->mops->initial_header_size) return fpga_mgr_write_init_buf(mgr, info, NULL, 0); /* * First try to use miter to map the first fragment to access the * header, this is the typical path. */ sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG); if (sg_miter_next(&miter) && miter.length >= mgr->mops->initial_header_size) { ret = fpga_mgr_write_init_buf(mgr, info, miter.addr, miter.length); sg_miter_stop(&miter); return ret; } sg_miter_stop(&miter); /* Otherwise copy the fragments into temporary memory. */ buf = kmalloc(mgr->mops->initial_header_size, GFP_KERNEL); if (!buf) return -ENOMEM; len = sg_copy_to_buffer(sgt->sgl, sgt->nents, buf, mgr->mops->initial_header_size); ret = fpga_mgr_write_init_buf(mgr, info, buf, len); kfree(buf); return ret; }

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/* * After all the FPGA image has been written, do the device specific steps to * finish and set the FPGA into operating mode. */
static int fpga_mgr_write_complete(struct fpga_manager *mgr, struct fpga_image_info *info) { int ret; mgr->state = FPGA_MGR_STATE_WRITE_COMPLETE; ret = mgr->mops->write_complete(mgr, info); if (ret) { dev_err(&mgr->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; }

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/** * fpga_mgr_buf_load_sg - load fpga from image in buffer from a scatter list * @mgr: fpga manager * @info: fpga image specific information * @sgt: scatterlist table * * 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() or fpga_mgr_get() and checked that it is * not an error code. * * This is the preferred entry point for FPGA programming, it does not require * any contiguous kernel memory. * * Return: 0 on success, negative error code otherwise. */
int fpga_mgr_buf_load_sg(struct fpga_manager *mgr, struct fpga_image_info *info, struct sg_table *sgt) { int ret; ret = fpga_mgr_write_init_sg(mgr, info, sgt); if (ret) return ret; /* Write the FPGA image to the FPGA. */ mgr->state = FPGA_MGR_STATE_WRITE; if (mgr->mops->write_sg) { ret = mgr->mops->write_sg(mgr, sgt); } else { struct sg_mapping_iter miter; sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG); while (sg_miter_next(&miter)) { ret = mgr->mops->write(mgr, miter.addr, miter.length); if (ret) break; } sg_miter_stop(&miter); } if (ret) { dev_err(&mgr->dev, "Error while writing image data to FPGA\n"); mgr->state = FPGA_MGR_STATE_WRITE_ERR; return ret; } return fpga_mgr_write_complete(mgr, info); }

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EXPORT_SYMBOL_GPL(fpga_mgr_buf_load_sg);
static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr, struct fpga_image_info *info, const char *buf, size_t count) { int ret; ret = fpga_mgr_write_init_buf(mgr, info, buf, count); if (ret) 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(&mgr->dev, "Error while writing image data to FPGA\n"); mgr->state = FPGA_MGR_STATE_WRITE_ERR; return ret; } return fpga_mgr_write_complete(mgr, info); }

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Alan Tull8886.27%266.67%
Jason Gunthorpe1413.73%133.33%
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/** * 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, struct fpga_image_info *info, const char *buf, size_t count) { struct page **pages; struct sg_table sgt; const void *p; int nr_pages; int index; int rc; /* * This is just a fast path if the caller has already created a * contiguous kernel buffer and the driver doesn't require SG, non-SG * drivers will still work on the slow path. */ if (mgr->mops->write) return fpga_mgr_buf_load_mapped(mgr, info, buf, count); /* * Convert the linear kernel pointer into a sg_table of pages for use * by the driver. */ nr_pages = DIV_ROUND_UP((unsigned long)buf + count, PAGE_SIZE) - (unsigned long)buf / PAGE_SIZE; pages = kmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL); if (!pages) return -ENOMEM; p = buf - offset_in_page(buf); for (index = 0; index < nr_pages; index++) { if (is_vmalloc_addr(p)) pages[index] = vmalloc_to_page(p); else pages[index] = kmap_to_page((void *)p); if (!pages[index]) { kfree(pages); return -EFAULT; } p += PAGE_SIZE; } /* * The temporary pages list is used to code share the merging algorithm * in sg_alloc_table_from_pages */ rc = sg_alloc_table_from_pages(&sgt, pages, index, offset_in_page(buf), count, GFP_KERNEL); kfree(pages); if (rc) return rc; rc = fpga_mgr_buf_load_sg(mgr, info, &sgt); sg_free_table(&sgt); return rc; }

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Jason Gunthorpe22489.24%133.33%
Alan Tull2710.76%266.67%
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EXPORT_SYMBOL_GPL(fpga_mgr_buf_load); /** * fpga_mgr_firmware_load - request firmware and load to fpga * @mgr: fpga manager * @info: fpga image specific information * @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() or 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, struct fpga_image_info *info, 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, info, fw->data, fw->size); release_firmware(fw); return ret; }

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Alan Tull11899.16%266.67%
Tobias Klauser10.84%133.33%
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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); }

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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]); }

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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);
struct fpga_manager *__fpga_mgr_get(struct device *dev) { struct fpga_manager *mgr; int ret = -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); }

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static int fpga_mgr_dev_match(struct device *dev, const void *data) { return dev->parent == data; }

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Alan Tull23100.00%1100.00%
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/** * fpga_mgr_get - get an exclusive reference to a fpga mgr * @dev: parent device that fpga mgr was registered with * * Given a device, get an exclusive reference to a fpga mgr. * * Return: fpga manager struct or IS_ERR() condition containing error code. */
struct fpga_manager *fpga_mgr_get(struct device *dev) { struct device *mgr_dev = class_find_device(fpga_mgr_class, NULL, dev, fpga_mgr_dev_match); if (!mgr_dev) return ERR_PTR(-ENODEV); return __fpga_mgr_get(mgr_dev); }

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EXPORT_SYMBOL_GPL(fpga_mgr_get);
static int fpga_mgr_of_node_match(struct device *dev, const void *data) { return dev->of_node == data; }

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/** * 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 device *dev; dev = class_find_device(fpga_mgr_class, NULL, node, fpga_mgr_of_node_match); if (!dev) return ERR_PTR(-ENODEV); return __fpga_mgr_get(dev); }

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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); }

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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_complete || !mops->state || !mops->write_init || (!mops->write && !mops->write_sg) || (mops->write && mops->write_sg)) { 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; }

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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); }

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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); }

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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; }

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static void __exit fpga_mgr_class_exit(void) { class_destroy(fpga_mgr_class); ida_destroy(&fpga_mgr_ida); }

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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);

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Directory: drivers/fpga
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