diff options
Diffstat (limited to 'drivers/fpga/dfl.c')
| -rw-r--r-- | drivers/fpga/dfl.c | 721 |
1 files changed, 721 insertions, 0 deletions
diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c new file mode 100644 index 000000000000..d1dff360ea14 --- /dev/null +++ b/drivers/fpga/dfl.c @@ -0,0 +1,721 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for FPGA Device Feature List (DFL) Support + * + * Copyright (C) 2017-2018 Intel Corporation, Inc. + * + * Authors: + * Kang Luwei <luwei.kang@intel.com> + * Zhang Yi <yi.z.zhang@intel.com> + * Wu Hao <hao.wu@intel.com> + * Xiao Guangrong <guangrong.xiao@linux.intel.com> + */ +#include <linux/module.h> + +#include "dfl.h" + +static DEFINE_MUTEX(dfl_id_mutex); + +/* + * when adding a new feature dev support in DFL framework, it's required to + * add a new item in enum dfl_id_type and provide related information in below + * dfl_devs table which is indexed by dfl_id_type, e.g. name string used for + * platform device creation (define name strings in dfl.h, as they could be + * reused by platform device drivers). + */ +enum dfl_id_type { + FME_ID, /* fme id allocation and mapping */ + PORT_ID, /* port id allocation and mapping */ + DFL_ID_MAX, +}; + +/** + * dfl_dev_info - dfl feature device information. + * @name: name string of the feature platform device. + * @dfh_id: id value in Device Feature Header (DFH) register by DFL spec. + * @id: idr id of the feature dev. + */ +struct dfl_dev_info { + const char *name; + u32 dfh_id; + struct idr id; +}; + +/* it is indexed by dfl_id_type */ +static struct dfl_dev_info dfl_devs[] = { + {.name = DFL_FPGA_FEATURE_DEV_FME, .dfh_id = DFH_ID_FIU_FME}, + {.name = DFL_FPGA_FEATURE_DEV_PORT, .dfh_id = DFH_ID_FIU_PORT}, +}; + +static void dfl_ids_init(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(dfl_devs); i++) + idr_init(&dfl_devs[i].id); +} + +static void dfl_ids_destroy(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(dfl_devs); i++) + idr_destroy(&dfl_devs[i].id); +} + +static int dfl_id_alloc(enum dfl_id_type type, struct device *dev) +{ + int id; + + WARN_ON(type >= DFL_ID_MAX); + mutex_lock(&dfl_id_mutex); + id = idr_alloc(&dfl_devs[type].id, dev, 0, 0, GFP_KERNEL); + mutex_unlock(&dfl_id_mutex); + + return id; +} + +static void dfl_id_free(enum dfl_id_type type, int id) +{ + WARN_ON(type >= DFL_ID_MAX); + mutex_lock(&dfl_id_mutex); + idr_remove(&dfl_devs[type].id, id); + mutex_unlock(&dfl_id_mutex); +} + +static enum dfl_id_type feature_dev_id_type(struct platform_device *pdev) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(dfl_devs); i++) + if (!strcmp(dfl_devs[i].name, pdev->name)) + return i; + + return DFL_ID_MAX; +} + +static enum dfl_id_type dfh_id_to_type(u32 id) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(dfl_devs); i++) + if (dfl_devs[i].dfh_id == id) + return i; + + return DFL_ID_MAX; +} + +/** + * struct build_feature_devs_info - info collected during feature dev build. + * + * @dev: device to enumerate. + * @cdev: the container device for all feature devices. + * @feature_dev: current feature device. + * @ioaddr: header register region address of feature device in enumeration. + * @sub_features: a sub features linked list for feature device in enumeration. + * @feature_num: number of sub features for feature device in enumeration. + */ +struct build_feature_devs_info { + struct device *dev; + struct dfl_fpga_cdev *cdev; + struct platform_device *feature_dev; + void __iomem *ioaddr; + struct list_head sub_features; + int feature_num; +}; + +/** + * struct dfl_feature_info - sub feature info collected during feature dev build + * + * @fid: id of this sub feature. + * @mmio_res: mmio resource of this sub feature. + * @ioaddr: mapped base address of mmio resource. + * @node: node in sub_features linked list. + */ +struct dfl_feature_info { + u64 fid; + struct resource mmio_res; + void __iomem *ioaddr; + struct list_head node; +}; + +static void dfl_fpga_cdev_add_port_dev(struct dfl_fpga_cdev *cdev, + struct platform_device *port) +{ + struct dfl_feature_platform_data *pdata = dev_get_platdata(&port->dev); + + mutex_lock(&cdev->lock); + list_add(&pdata->node, &cdev->port_dev_list); + get_device(&pdata->dev->dev); + mutex_unlock(&cdev->lock); +} + +/* + * register current feature device, it is called when we need to switch to + * another feature parsing or we have parsed all features on given device + * feature list. + */ +static int build_info_commit_dev(struct build_feature_devs_info *binfo) +{ + struct platform_device *fdev = binfo->feature_dev; + struct dfl_feature_platform_data *pdata; + struct dfl_feature_info *finfo, *p; + int ret, index = 0; + + if (!fdev) + return 0; + + /* + * we do not need to care for the memory which is associated with + * the platform device. After calling platform_device_unregister(), + * it will be automatically freed by device's release() callback, + * platform_device_release(). + */ + pdata = kzalloc(dfl_feature_platform_data_size(binfo->feature_num), + GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + pdata->dev = fdev; + pdata->num = binfo->feature_num; + pdata->dfl_cdev = binfo->cdev; + mutex_init(&pdata->lock); + + /* + * the count should be initialized to 0 to make sure + *__fpga_port_enable() following __fpga_port_disable() + * works properly for port device. + * and it should always be 0 for fme device. + */ + WARN_ON(pdata->disable_count); + + fdev->dev.platform_data = pdata; + + /* each sub feature has one MMIO resource */ + fdev->num_resources = binfo->feature_num; + fdev->resource = kcalloc(binfo->feature_num, sizeof(*fdev->resource), + GFP_KERNEL); + if (!fdev->resource) + return -ENOMEM; + + /* fill features and resource information for feature dev */ + list_for_each_entry_safe(finfo, p, &binfo->sub_features, node) { + struct dfl_feature *feature = &pdata->features[index]; + + /* save resource information for each feature */ + feature->id = finfo->fid; + feature->resource_index = index; + feature->ioaddr = finfo->ioaddr; + fdev->resource[index++] = finfo->mmio_res; + + list_del(&finfo->node); + kfree(finfo); + } + + ret = platform_device_add(binfo->feature_dev); + if (!ret) { + if (feature_dev_id_type(binfo->feature_dev) == PORT_ID) + dfl_fpga_cdev_add_port_dev(binfo->cdev, + binfo->feature_dev); + else + binfo->cdev->fme_dev = + get_device(&binfo->feature_dev->dev); + /* + * reset it to avoid build_info_free() freeing their resource. + * + * The resource of successfully registered feature devices + * will be freed by platform_device_unregister(). See the + * comments in build_info_create_dev(). + */ + binfo->feature_dev = NULL; + } + + return ret; +} + +static int +build_info_create_dev(struct build_feature_devs_info *binfo, + enum dfl_id_type type, void __iomem *ioaddr) +{ + struct platform_device *fdev; + int ret; + + if (type >= DFL_ID_MAX) + return -EINVAL; + + /* we will create a new device, commit current device first */ + ret = build_info_commit_dev(binfo); + if (ret) + return ret; + + /* + * we use -ENODEV as the initialization indicator which indicates + * whether the id need to be reclaimed + */ + fdev = platform_device_alloc(dfl_devs[type].name, -ENODEV); + if (!fdev) + return -ENOMEM; + + binfo->feature_dev = fdev; + binfo->feature_num = 0; + binfo->ioaddr = ioaddr; + INIT_LIST_HEAD(&binfo->sub_features); + + fdev->id = dfl_id_alloc(type, &fdev->dev); + if (fdev->id < 0) + return fdev->id; + + fdev->dev.parent = &binfo->cdev->region->dev; + + return 0; +} + +static void build_info_free(struct build_feature_devs_info *binfo) +{ + struct dfl_feature_info *finfo, *p; + + /* + * it is a valid id, free it. See comments in + * build_info_create_dev() + */ + if (binfo->feature_dev && binfo->feature_dev->id >= 0) { + dfl_id_free(feature_dev_id_type(binfo->feature_dev), + binfo->feature_dev->id); + + list_for_each_entry_safe(finfo, p, &binfo->sub_features, node) { + list_del(&finfo->node); + kfree(finfo); + } + } + + platform_device_put(binfo->feature_dev); + + devm_kfree(binfo->dev, binfo); +} + +static inline u32 feature_size(void __iomem *start) +{ + u64 v = readq(start + DFH); + u32 ofst = FIELD_GET(DFH_NEXT_HDR_OFST, v); + /* workaround for private features with invalid size, use 4K instead */ + return ofst ? ofst : 4096; +} + +static u64 feature_id(void __iomem *start) +{ + u64 v = readq(start + DFH); + u16 id = FIELD_GET(DFH_ID, v); + u8 type = FIELD_GET(DFH_TYPE, v); + + if (type == DFH_TYPE_FIU) + return FEATURE_ID_FIU_HEADER; + else if (type == DFH_TYPE_PRIVATE) + return id; + else if (type == DFH_TYPE_AFU) + return FEATURE_ID_AFU; + + WARN_ON(1); + return 0; +} + +/* + * when create sub feature instances, for private features, it doesn't need + * to provide resource size and feature id as they could be read from DFH + * register. For afu sub feature, its register region only contains user + * defined registers, so never trust any information from it, just use the + * resource size information provided by its parent FIU. + */ +static int +create_feature_instance(struct build_feature_devs_info *binfo, + struct dfl_fpga_enum_dfl *dfl, resource_size_t ofst, + resource_size_t size, u64 fid) +{ + struct dfl_feature_info *finfo; + + /* read feature size and id if inputs are invalid */ + size = size ? size : feature_size(dfl->ioaddr + ofst); + fid = fid ? fid : feature_id(dfl->ioaddr + ofst); + + if (dfl->len - ofst < size) + return -EINVAL; + + finfo = kzalloc(sizeof(*finfo), GFP_KERNEL); + if (!finfo) + return -ENOMEM; + + finfo->fid = fid; + finfo->mmio_res.start = dfl->start + ofst; + finfo->mmio_res.end = finfo->mmio_res.start + size - 1; + finfo->mmio_res.flags = IORESOURCE_MEM; + finfo->ioaddr = dfl->ioaddr + ofst; + + list_add_tail(&finfo->node, &binfo->sub_features); + binfo->feature_num++; + + return 0; +} + +static int parse_feature_port_afu(struct build_feature_devs_info *binfo, + struct dfl_fpga_enum_dfl *dfl, + resource_size_t ofst) +{ + u64 v = readq(binfo->ioaddr + PORT_HDR_CAP); + u32 size = FIELD_GET(PORT_CAP_MMIO_SIZE, v) << 10; + + WARN_ON(!size); + + return create_feature_instance(binfo, dfl, ofst, size, FEATURE_ID_AFU); +} + +static int parse_feature_afu(struct build_feature_devs_info *binfo, + struct dfl_fpga_enum_dfl *dfl, + resource_size_t ofst) +{ + if (!binfo->feature_dev) { + dev_err(binfo->dev, "this AFU does not belong to any FIU.\n"); + return -EINVAL; + } + + switch (feature_dev_id_type(binfo->feature_dev)) { + case PORT_ID: + return parse_feature_port_afu(binfo, dfl, ofst); + default: + dev_info(binfo->dev, "AFU belonging to FIU %s is not supported yet.\n", + binfo->feature_dev->name); + } + + return 0; +} + +static int parse_feature_fiu(struct build_feature_devs_info *binfo, + struct dfl_fpga_enum_dfl *dfl, + resource_size_t ofst) +{ + u32 id, offset; + u64 v; + int ret = 0; + + v = readq(dfl->ioaddr + ofst + DFH); + id = FIELD_GET(DFH_ID, v); + + /* create platform device for dfl feature dev */ + ret = build_info_create_dev(binfo, dfh_id_to_type(id), + dfl->ioaddr + ofst); + if (ret) + return ret; + + ret = create_feature_instance(binfo, dfl, ofst, 0, 0); + if (ret) + return ret; + /* + * find and parse FIU's child AFU via its NEXT_AFU register. + * please note that only Port has valid NEXT_AFU pointer per spec. + */ + v = readq(dfl->ioaddr + ofst + NEXT_AFU); + + offset = FIELD_GET(NEXT_AFU_NEXT_DFH_OFST, v); + if (offset) + return parse_feature_afu(binfo, dfl, ofst + offset); + + dev_dbg(binfo->dev, "No AFUs detected on FIU %d\n", id); + + return ret; +} + +static int parse_feature_private(struct build_feature_devs_info *binfo, + struct dfl_fpga_enum_dfl *dfl, + resource_size_t ofst) +{ + if (!binfo->feature_dev) { + dev_err(binfo->dev, "the private feature %llx does not belong to any AFU.\n", + (unsigned long long)feature_id(dfl->ioaddr + ofst)); + return -EINVAL; + } + + return create_feature_instance(binfo, dfl, ofst, 0, 0); +} + +/** + * parse_feature - parse a feature on given device feature list + * + * @binfo: build feature devices information. + * @dfl: device feature list to parse + * @ofst: offset to feature header on this device feature list + */ +static int parse_feature(struct build_feature_devs_info *binfo, + struct dfl_fpga_enum_dfl *dfl, resource_size_t ofst) +{ + u64 v; + u32 type; + + v = readq(dfl->ioaddr + ofst + DFH); + type = FIELD_GET(DFH_TYPE, v); + + switch (type) { + case DFH_TYPE_AFU: + return parse_feature_afu(binfo, dfl, ofst); + case DFH_TYPE_PRIVATE: + return parse_feature_private(binfo, dfl, ofst); + case DFH_TYPE_FIU: + return parse_feature_fiu(binfo, dfl, ofst); + default: + dev_info(binfo->dev, + "Feature Type %x is not supported.\n", type); + } + + return 0; +} + +static int parse_feature_list(struct build_feature_devs_info *binfo, + struct dfl_fpga_enum_dfl *dfl) +{ + void __iomem *start = dfl->ioaddr; + void __iomem *end = dfl->ioaddr + dfl->len; + int ret = 0; + u32 ofst = 0; + u64 v; + + /* walk through the device feature list via DFH's next DFH pointer. */ + for (; start < end; start += ofst) { + if (end - start < DFH_SIZE) { + dev_err(binfo->dev, "The region is too small to contain a feature.\n"); + return -EINVAL; + } + + ret = parse_feature(binfo, dfl, start - dfl->ioaddr); + if (ret) + return ret; + + v = readq(start + DFH); + ofst = FIELD_GET(DFH_NEXT_HDR_OFST, v); + + /* stop parsing if EOL(End of List) is set or offset is 0 */ + if ((v & DFH_EOL) || !ofst) + break; + } + + /* commit current feature device when reach the end of list */ + return build_info_commit_dev(binfo); +} + +struct dfl_fpga_enum_info *dfl_fpga_enum_info_alloc(struct device *dev) +{ + struct dfl_fpga_enum_info *info; + + get_device(dev); + + info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); + if (!info) { + put_device(dev); + return NULL; + } + + info->dev = dev; + INIT_LIST_HEAD(&info->dfls); + + return info; +} +EXPORT_SYMBOL_GPL(dfl_fpga_enum_info_alloc); + +void dfl_fpga_enum_info_free(struct dfl_fpga_enum_info *info) +{ + struct dfl_fpga_enum_dfl *tmp, *dfl; + struct device *dev; + + if (!info) + return; + + dev = info->dev; + + /* remove all device feature lists in the list. */ + list_for_each_entry_safe(dfl, tmp, &info->dfls, node) { + list_del(&dfl->node); + devm_kfree(dev, dfl); + } + + devm_kfree(dev, info); + put_device(dev); +} +EXPORT_SYMBOL_GPL(dfl_fpga_enum_info_free); + +/** + * dfl_fpga_enum_info_add_dfl - add info of a device feature list to enum info + * + * @info: ptr to dfl_fpga_enum_info + * @start: mmio resource address of the device feature list. + * @len: mmio resource length of the device feature list. + * @ioaddr: mapped mmio resource address of the device feature list. + * + * One FPGA device may have one or more Device Feature Lists (DFLs), use this + * function to add information of each DFL to common data structure for next + * step enumeration. + * + * Return: 0 on success, negative error code otherwise. + */ +int dfl_fpga_enum_info_add_dfl(struct dfl_fpga_enum_info *info, + resource_size_t start, resource_size_t len, + void __iomem *ioaddr) +{ + struct dfl_fpga_enum_dfl *dfl; + + dfl = devm_kzalloc(info->dev, sizeof(*dfl), GFP_KERNEL); + if (!dfl) + return -ENOMEM; + + dfl->start = start; + dfl->len = len; + dfl->ioaddr = ioaddr; + + list_add_tail(&dfl->node, &info->dfls); + + return 0; +} +EXPORT_SYMBOL_GPL(dfl_fpga_enum_info_add_dfl); + +static int remove_feature_dev(struct device *dev, void *data) +{ + struct platform_device *pdev = to_platform_device(dev); + enum dfl_id_type type = feature_dev_id_type(pdev); + int id = pdev->id; + + platform_device_unregister(pdev); + + dfl_id_free(type, id); + + return 0; +} + +static void remove_feature_devs(struct dfl_fpga_cdev *cdev) +{ + device_for_each_child(&cdev->region->dev, NULL, remove_feature_dev); +} + +/** + * dfl_fpga_feature_devs_enumerate - enumerate feature devices + * @info: information for enumeration. + * + * This function creates a container device (base FPGA region), enumerates + * feature devices based on the enumeration info and creates platform devices + * under the container device. + * + * Return: dfl_fpga_cdev struct on success, -errno on failure + */ +struct dfl_fpga_cdev * +dfl_fpga_feature_devs_enumerate(struct dfl_fpga_enum_info *info) +{ + struct build_feature_devs_info *binfo; + struct dfl_fpga_enum_dfl *dfl; + struct dfl_fpga_cdev *cdev; + int ret = 0; + + if (!info->dev) + return ERR_PTR(-ENODEV); + + cdev = devm_kzalloc(info->dev, sizeof(*cdev), GFP_KERNEL); + if (!cdev) + return ERR_PTR(-ENOMEM); + + cdev->region = fpga_region_create(info->dev, NULL, NULL); + if (!cdev->region) { + ret = -ENOMEM; + goto free_cdev_exit; + } + + cdev->parent = info->dev; + mutex_init(&cdev->lock); + INIT_LIST_HEAD(&cdev->port_dev_list); + + ret = fpga_region_register(cdev->region); + if (ret) + goto free_region_exit; + + /* create and init build info for enumeration */ + binfo = devm_kzalloc(info->dev, sizeof(*binfo), GFP_KERNEL); + if (!binfo) { + ret = -ENOMEM; + goto unregister_region_exit; + } + + binfo->dev = info->dev; + binfo->cdev = cdev; + + /* + * start enumeration for all feature devices based on Device Feature + * Lists. + */ + list_for_each_entry(dfl, &info->dfls, node) { + ret = parse_feature_list(binfo, dfl); + if (ret) { + remove_feature_devs(cdev); + build_info_free(binfo); + goto unregister_region_exit; + } + } + + build_info_free(binfo); + + return cdev; + +unregister_region_exit: + fpga_region_unregister(cdev->region); +free_region_exit: + fpga_region_free(cdev->region); +free_cdev_exit: + devm_kfree(info->dev, cdev); + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(dfl_fpga_feature_devs_enumerate); + +/** + * dfl_fpga_feature_devs_remove - remove all feature devices + * @cdev: fpga container device. + * + * Remove the container device and all feature devices under given container + * devices. + */ +void dfl_fpga_feature_devs_remove(struct dfl_fpga_cdev *cdev) +{ + struct dfl_feature_platform_data *pdata, *ptmp; + + remove_feature_devs(cdev); + + mutex_lock(&cdev->lock); + if (cdev->fme_dev) { + /* the fme should be unregistered. */ + WARN_ON(device_is_registered(cdev->fme_dev)); + put_device(cdev->fme_dev); + } + + list_for_each_entry_safe(pdata, ptmp, &cdev->port_dev_list, node) { + struct platform_device *port_dev = pdata->dev; + + /* the port should be unregistered. */ + WARN_ON(device_is_registered(&port_dev->dev)); + list_del(&pdata->node); + put_device(&port_dev->dev); + } + mutex_unlock(&cdev->lock); + + fpga_region_unregister(cdev->region); + devm_kfree(cdev->parent, cdev); +} +EXPORT_SYMBOL_GPL(dfl_fpga_feature_devs_remove); + +static int __init dfl_fpga_init(void) +{ + dfl_ids_init(); + + return 0; +} + +static void __exit dfl_fpga_exit(void) +{ + dfl_ids_destroy(); +} + +module_init(dfl_fpga_init); +module_exit(dfl_fpga_exit); + +MODULE_DESCRIPTION("FPGA Device Feature List (DFL) Support"); +MODULE_AUTHOR("Intel Corporation"); +MODULE_LICENSE("GPL v2"); |