diff options
Diffstat (limited to 'drivers/fpga/fpga-mgr.c')
| -rw-r--r-- | drivers/fpga/fpga-mgr.c | 714 |
1 files changed, 714 insertions, 0 deletions
diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c new file mode 100644 index 000000000..a41b07e37 --- /dev/null +++ b/drivers/fpga/fpga-mgr.c @@ -0,0 +1,714 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * FPGA Manager Core + * + * Copyright (C) 2013-2015 Altera Corporation + * Copyright (C) 2017 Intel Corporation + * + * With code from the mailing list: + * Copyright (C) 2013 Xilinx, Inc. + */ +#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; + +/** + * fpga_image_info_alloc - Allocate a FPGA image info struct + * @dev: owning device + * + * Return: struct fpga_image_info or NULL + */ +struct fpga_image_info *fpga_image_info_alloc(struct device *dev) +{ + struct fpga_image_info *info; + + get_device(dev); + + info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); + if (!info) { + put_device(dev); + return NULL; + } + + info->dev = dev; + + return info; +} +EXPORT_SYMBOL_GPL(fpga_image_info_alloc); + +/** + * fpga_image_info_free - Free a FPGA image info struct + * @info: FPGA image info struct to free + */ +void fpga_image_info_free(struct fpga_image_info *info) +{ + struct device *dev; + + if (!info) + return; + + dev = info->dev; + if (info->firmware_name) + devm_kfree(dev, info->firmware_name); + + devm_kfree(dev, info); + put_device(dev); +} +EXPORT_SYMBOL_GPL(fpga_image_info_free); + +/* + * 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; +} + +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; +} + +/* + * 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; +} + +/** + * 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. + */ +static 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); +} + +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); +} + +/** + * fpga_mgr_buf_load - load fpga from image in buffer + * @mgr: fpga manager + * @info: fpga image info + * @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. + */ +static 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; +} + +/** + * 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. + */ +static 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; +} + +/** + * fpga_mgr_load - load FPGA from scatter/gather table, buffer, or firmware + * @mgr: fpga manager + * @info: fpga image information. + * + * Load the FPGA from an image which is indicated in @info. If successful, the + * FPGA ends up in operating mode. + * + * Return: 0 on success, negative error code otherwise. + */ +int fpga_mgr_load(struct fpga_manager *mgr, struct fpga_image_info *info) +{ + if (info->sgt) + return fpga_mgr_buf_load_sg(mgr, info, info->sgt); + if (info->buf && info->count) + return fpga_mgr_buf_load(mgr, info, info->buf, info->count); + if (info->firmware_name) + return fpga_mgr_firmware_load(mgr, info, info->firmware_name); + return -EINVAL; +} +EXPORT_SYMBOL_GPL(fpga_mgr_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 ssize_t status_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct fpga_manager *mgr = to_fpga_manager(dev); + u64 status; + int len = 0; + + if (!mgr->mops->status) + return -ENOENT; + + status = mgr->mops->status(mgr); + + if (status & FPGA_MGR_STATUS_OPERATION_ERR) + len += sprintf(buf + len, "reconfig operation error\n"); + if (status & FPGA_MGR_STATUS_CRC_ERR) + len += sprintf(buf + len, "reconfig CRC error\n"); + if (status & FPGA_MGR_STATUS_INCOMPATIBLE_IMAGE_ERR) + len += sprintf(buf + len, "reconfig incompatible image\n"); + if (status & FPGA_MGR_STATUS_IP_PROTOCOL_ERR) + len += sprintf(buf + len, "reconfig IP protocol error\n"); + if (status & FPGA_MGR_STATUS_FIFO_OVERFLOW_ERR) + len += sprintf(buf + len, "reconfig fifo overflow error\n"); + + return len; +} + +static DEVICE_ATTR_RO(name); +static DEVICE_ATTR_RO(state); +static DEVICE_ATTR_RO(status); + +static struct attribute *fpga_mgr_attrs[] = { + &dev_attr_name.attr, + &dev_attr_state.attr, + &dev_attr_status.attr, + NULL, +}; +ATTRIBUTE_GROUPS(fpga_mgr); + +static struct fpga_manager *__fpga_mgr_get(struct device *dev) +{ + struct fpga_manager *mgr; + + mgr = to_fpga_manager(dev); + + if (!try_module_get(dev->parent->driver->owner)) + goto err_dev; + + return mgr; + +err_dev: + put_device(dev); + return ERR_PTR(-ENODEV); +} + +static int fpga_mgr_dev_match(struct device *dev, const void *data) +{ + return dev->parent == data; +} + +/** + * fpga_mgr_get - Given a device, get a reference to a fpga mgr. + * @dev: parent device that fpga mgr was registered with + * + * 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); +} +EXPORT_SYMBOL_GPL(fpga_mgr_get); + +static int fpga_mgr_of_node_match(struct device *dev, const void *data) +{ + return dev->of_node == data; +} + +/** + * of_fpga_mgr_get - Given a device node, get a reference to a fpga mgr. + * + * @node: device node + * + * 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); +} +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); + put_device(&mgr->dev); +} +EXPORT_SYMBOL_GPL(fpga_mgr_put); + +/** + * fpga_mgr_lock - Lock FPGA manager for exclusive use + * @mgr: fpga manager + * + * Given a pointer to FPGA Manager (from fpga_mgr_get() or + * of_fpga_mgr_put()) attempt to get the mutex. The user should call + * fpga_mgr_lock() and verify that it returns 0 before attempting to + * program the FPGA. Likewise, the user should call fpga_mgr_unlock + * when done programming the FPGA. + * + * Return: 0 for success or -EBUSY + */ +int fpga_mgr_lock(struct fpga_manager *mgr) +{ + if (!mutex_trylock(&mgr->ref_mutex)) { + dev_err(&mgr->dev, "FPGA manager is in use.\n"); + return -EBUSY; + } + + return 0; +} +EXPORT_SYMBOL_GPL(fpga_mgr_lock); + +/** + * fpga_mgr_unlock - Unlock FPGA manager after done programming + * @mgr: fpga manager + */ +void fpga_mgr_unlock(struct fpga_manager *mgr) +{ + mutex_unlock(&mgr->ref_mutex); +} +EXPORT_SYMBOL_GPL(fpga_mgr_unlock); + +/** + * fpga_mgr_create - create and initialize a FPGA manager struct + * @dev: fpga manager device from pdev + * @name: fpga manager name + * @mops: pointer to structure of fpga manager ops + * @priv: fpga manager private data + * + * Return: pointer to struct fpga_manager or NULL + */ +struct fpga_manager *fpga_mgr_create(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 NULL; + } + + if (!name || !strlen(name)) { + dev_err(dev, "Attempt to register with no name!\n"); + return NULL; + } + + mgr = kzalloc(sizeof(*mgr), GFP_KERNEL); + if (!mgr) + return NULL; + + 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; + + device_initialize(&mgr->dev); + mgr->dev.class = fpga_mgr_class; + mgr->dev.groups = mops->groups; + mgr->dev.parent = dev; + mgr->dev.of_node = dev->of_node; + mgr->dev.id = id; + + ret = dev_set_name(&mgr->dev, "fpga%d", id); + if (ret) + goto error_device; + + return mgr; + +error_device: + ida_simple_remove(&fpga_mgr_ida, id); +error_kfree: + kfree(mgr); + + return NULL; +} +EXPORT_SYMBOL_GPL(fpga_mgr_create); + +/** + * fpga_mgr_free - deallocate a FPGA manager + * @mgr: fpga manager struct created by fpga_mgr_create + */ +void fpga_mgr_free(struct fpga_manager *mgr) +{ + ida_simple_remove(&fpga_mgr_ida, mgr->dev.id); + kfree(mgr); +} +EXPORT_SYMBOL_GPL(fpga_mgr_free); + +/** + * fpga_mgr_register - register a FPGA manager + * @mgr: fpga manager struct created by fpga_mgr_create + * + * Return: 0 on success, negative error code otherwise. + */ +int fpga_mgr_register(struct fpga_manager *mgr) +{ + int ret; + + /* + * 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); + + 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, mgr->dev.id); + + return ret; +} +EXPORT_SYMBOL_GPL(fpga_mgr_register); + +/** + * fpga_mgr_unregister - unregister and free a FPGA manager + * @mgr: fpga manager struct + */ +void fpga_mgr_unregister(struct fpga_manager *mgr) +{ + 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); + + fpga_mgr_free(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@kernel.org>"); +MODULE_DESCRIPTION("FPGA manager framework"); +MODULE_LICENSE("GPL v2"); + +subsys_initcall(fpga_mgr_class_init); +module_exit(fpga_mgr_class_exit); |