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Diffstat (limited to 'include/bootdev.h')
| -rw-r--r-- | include/bootdev.h | 443 |
1 files changed, 443 insertions, 0 deletions
diff --git a/include/bootdev.h b/include/bootdev.h new file mode 100644 index 00000000000..12c90c4ec1b --- /dev/null +++ b/include/bootdev.h @@ -0,0 +1,443 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright 2021 Google LLC + * Written by Simon Glass <sjg@chromium.org> + */ + +#ifndef __bootdev_h +#define __bootdev_h + +#include <dm/uclass-id.h> +#include <linux/list.h> + +struct bootflow; +struct bootflow_iter; +struct bootstd_priv; +struct udevice; + +/** + * enum bootdev_prio_t - priority of each bootdev + * + * These values are associated with each bootdev and set up by the driver. + * + * Smallest value is the highest priority. By default, bootdevs are scanned from + * highest to lowest priority + * + * BOOTDEVP_0_NONE: Invalid value, do not use + * @BOOTDEVP_6_PRE_SCAN: Scan bootdevs with this priority always, before + * starting any bootflow scan + * @BOOTDEVP_2_INTERNAL_FAST: Internal devices which don't need scanning and + * generally very quick to access, e.g. less than 100ms + * @BOOTDEVP_3_INTERNAL_SLOW: Internal devices which don't need scanning but + * take a significant fraction of a second to access + * @BOOTDEVP_4_SCAN_FAST: Extenal devices which need scanning or bus + * enumeration to find, but this enumeration happens quickly, typically under + * 100ms + * @BOOTDEVP_5_SCAN_SLOW: Extenal devices which need scanning or bus + * enumeration to find. The enumeration takes significant fraction of a second + * to complete + * @BOOTDEVP_6_NET_BASE: Basic network devices which are quickly and easily + * available. Typically used for an internal Ethernet device + * @BOOTDEVP_7_NET_FALLBACK: Secondary network devices which require extra time + * to start up, or are less desirable. Typically used for secondary Ethernet + * devices. Note that USB ethernet devices are found during USB enumeration, + * so do not use this priority + */ +enum bootdev_prio_t { + BOOTDEVP_0_NONE, + BOOTDEVP_1_PRE_SCAN, + BOOTDEVP_2_INTERNAL_FAST, + BOOTDEVP_3_INTERNAL_SLOW, + BOOTDEVP_4_SCAN_FAST, + BOOTDEVP_5_SCAN_SLOW, + BOOTDEVP_6_NET_BASE, + BOOTDEVP_7_NET_FALLBACK, + + BOOTDEVP_COUNT, +}; + +struct bootdev_hunter; + +/** + * bootdev_hunter_func - function to probe for bootdevs of a given type + * + * This should hunt around for bootdevs of the given type, binding them as it + * finds them. This may involve bus enumeration, etc. + * + * @info: Info structure describing this hunter + * @show: true to show information from the hunter + * Returns: 0 if OK, -ENOENT on device not found, otherwise -ve on error + */ +typedef int (*bootdev_hunter_func)(struct bootdev_hunter *info, bool show); + +/** + * struct bootdev_hunter - information about how to hunt for bootdevs + * + * @prio: Scanning priority of this hunter + * @uclass: Uclass ID for the media associated with this bootdev + * @drv: bootdev driver for the things found by this hunter + * @hunt: Function to call to hunt for bootdevs of this type (NULL if none) + * + * Some bootdevs are not visible until other devices are enumerated. For + * example, USB bootdevs only appear when the USB bus is enumerated. + * + * On the other hand, we don't always want to enumerate all the buses just to + * find the first valid bootdev. Ideally we want to work through them in + * priority order, so that the fastest bootdevs are discovered first. + * + * This struct holds information about the bootdev so we can determine the probe + * order and how to hunt for bootdevs of this type + */ +struct bootdev_hunter { + enum bootdev_prio_t prio; + enum uclass_id uclass; + struct driver *drv; + bootdev_hunter_func hunt; +}; + +/* declare a new bootdev hunter */ +#define BOOTDEV_HUNTER(__name) \ + ll_entry_declare(struct bootdev_hunter, __name, bootdev_hunter) + +/* access a bootdev hunter by name */ +#define BOOTDEV_HUNTER_GET(__name) \ + ll_entry_get(struct bootdev_hunter, __name, bootdev_hunter) + +/** + * struct bootdev_uc_plat - uclass information about a bootdev + * + * This is attached to each device in the bootdev uclass and accessible via + * dev_get_uclass_plat(dev) + * + * @piro: Priority of this bootdev + */ +struct bootdev_uc_plat { + enum bootdev_prio_t prio; +}; + +/** struct bootdev_ops - Operations for the bootdev uclass */ +struct bootdev_ops { + /** + * get_bootflow() - get a bootflow (optional) + * + * If this is NULL then the default implementaton is used, which is + * default_get_bootflow() + * + * @dev: Bootflow device to check + * @iter: Provides current dev, part, method to get. Should update + * max_part if there is a partition table. Should update state, + * subdir, fname, buf, size according to progress + * @bflow: Updated bootflow if found + * Return: 0 if OK, -ESHUTDOWN if there are no more bootflows on this + * device, -ENOSYS if this device doesn't support bootflows, + * other -ve value on other error + */ + int (*get_bootflow)(struct udevice *dev, struct bootflow_iter *iter, + struct bootflow *bflow); +}; + +#define bootdev_get_ops(dev) ((struct bootdev_ops *)(dev)->driver->ops) + +/** + * bootdev_get_bootflow() - get a bootflow + * + * @dev: Bootflow device to check + * @iter: Provides current part, method to get + * @bflow: Returns bootflow if found + * Return: 0 if OK, -ESHUTDOWN if there are no more bootflows on this device, + * -ENOSYS if this device doesn't support bootflows, other -ve value on + * other error + */ +int bootdev_get_bootflow(struct udevice *dev, struct bootflow_iter *iter, + struct bootflow *bflow); + +/** + * bootdev_bind() - Bind a new named bootdev device + * + * @parent: Parent of the new device + * @drv_name: Driver name to use for the bootdev device + * @name: Name for the device (parent name is prepended) + * @devp: the new device (which has not been probed) + */ +int bootdev_bind(struct udevice *parent, const char *drv_name, const char *name, + struct udevice **devp); + +/** + * bootdev_find_in_blk() - Find a bootdev in a block device + * + * @dev: Bootflow device associated with this block device + * @blk: Block device to search + * @iter: Provides current dev, part, method to get. Should update + * max_part if there is a partition table + * @bflow: On entry, provides information about the partition and device to + * check. On exit, returns bootflow if found + * Return: 0 if found, -ESHUTDOWN if no more bootflows, other -ve on error + */ +int bootdev_find_in_blk(struct udevice *dev, struct udevice *blk, + struct bootflow_iter *iter, struct bootflow *bflow); + +/** + * bootdev_list() - List all available bootdevs + * + * @probe: true to probe devices, false to leave them as is + */ +void bootdev_list(bool probe); + +/** + * bootdev_first_bootflow() - Get the first bootflow from a bootdev + * + * Returns the first bootflow attached to a bootdev + * + * @dev: bootdev device + * @bflowp: Returns a pointer to the bootflow + * Return: 0 if found, -ENOENT if there are no bootflows + */ +int bootdev_first_bootflow(struct udevice *dev, struct bootflow **bflowp); + +/** + * bootdev_next_bootflow() - Get the next bootflow from a bootdev + * + * Returns the next bootflow attached to a bootdev + * + * @bflowp: On entry, the last bootflow returned , e.g. from + * bootdev_first_bootflow() + * Return: 0 if found, -ENOENT if there are no more bootflows + */ +int bootdev_next_bootflow(struct bootflow **bflowp); + +/** + * bootdev_find_by_label() - Look up a bootdev by label + * + * Each bootdev has a label which contains the media-uclass name and a number, + * e.g. 'mmc2'. This looks up the label and returns the associated bootdev + * + * The lookup is performed based on the media device's sequence number. So for + * 'mmc2' this looks for a device in UCLASS_MMC with a dev_seq() of 2. + * + * @label: Label to look up (e.g. "mmc1" or "mmc0") + * @devp: Returns the bootdev device found, or NULL if none (note it does not + * return the media device, but its bootdev child) + * @method_flagsp: If non-NULL, returns any flags implied by the label + * (enum bootflow_meth_flags_t), 0 if none. Unset if function fails + * Return: 0 if OK, -EINVAL if the uclass is not supported by this board, + * -ENOENT if there is no device with that number + */ +int bootdev_find_by_label(const char *label, struct udevice **devp, + int *method_flagsp); + +/** + * bootdev_find_by_any() - Find a bootdev by name, label or sequence + * + * @name: name (e.g. "mmc2.bootdev"), label ("mmc2"), or sequence ("2") to find + * @devp: returns the device found, on success + * @method_flagsp: If non-NULL, returns any flags implied by the label + * (enum bootflow_meth_flags_t), 0 if none. Unset if function fails + * Return: 0 if OK, -EPFNOSUPPORT if the uclass is not supported by this board, + * -ENOENT if there is no device with that number + */ +int bootdev_find_by_any(const char *name, struct udevice **devp, + int *method_flagsp); + +/** + * bootdev_setup_iter() - Set up iteration through bootdevs + * + * This sets up the an interation, based on the provided device or label. If + * neither is provided, the iteration is based on the priority of each bootdev, + * the * bootdev-order property in the bootstd node (or the boot_targets env + * var). + * + * @iter: Iterator to update with the order + * @label: label to scan, or NULL to scan all + * @devp: On entry, *devp is NULL to scan all, otherwise this is the (single) + * device to scan. Returns the first device to use, which is the passed-in + * @devp if it was non-NULL + * @method_flagsp: If non-NULL, returns any flags implied by the label + * (enum bootflow_meth_flags_t), 0 if none + * Return: 0 if OK, -ENOENT if no bootdevs, -ENOMEM if out of memory, other -ve + * on other error + */ +int bootdev_setup_iter(struct bootflow_iter *iter, const char *label, + struct udevice **devp, int *method_flagsp); + +/** + * bootdev_list_hunters() - List the available bootdev hunters + * + * These provide a way to find new bootdevs by enumerating buses, etc. This + * function lists the available hunters + * + * @std: Pointer to bootstd private info + */ +void bootdev_list_hunters(struct bootstd_priv *std); + +/** + * bootdev_hunt() - Hunt for bootdevs matching a particular spec + * + * This runs the selected hunter (or all if @spec is NULL) to try to find new + * bootdevs. + * + * @spec: Spec to match, e.g. "mmc0", or NULL for any. If provided, this must + * match a uclass name so that the hunter can be determined. Any trailing number + * is ignored + * @show: true to show each hunter before using it + * Returns: 0 if OK, -ve on error + */ +int bootdev_hunt(const char *spec, bool show); + +/** + * bootdev_hunt_prio() - Hunt for bootdevs of a particular priority + * + * This runs all hunters which can find bootdevs of the given priority. + * + * @prio: Priority to use + * @show: true to show each hunter as it is used + * Returns: 0 if OK, -ve on error + */ +int bootdev_hunt_prio(enum bootdev_prio_t prio, bool show); + +/** + * bootdev_unhunt() - Mark a device as needing to be hunted again + * + * @id: uclass ID to update + * Return: 0 if done, -EALREADY if already in this state, -ENOENT if no hunter + * found for that uclass + */ +int bootdev_unhunt(enum uclass_id id); + +/** + * bootdev_hunt_and_find_by_label() - Hunt for bootdevs by label + * + * Runs the hunter for the label, then tries to find the bootdev, possible + * created by the hunter + * + * @label: Label to look up (e.g. "mmc1" or "mmc0") + * @devp: Returns the bootdev device found, or NULL if none (note it does not + * return the media device, but its bootdev child) + * @method_flagsp: If non-NULL, returns any flags implied by the label + * (enum bootflow_meth_flags_t), 0 if none. Unset if function fails + * Return: 0 if OK, -EINVAL if the uclass is not supported by this board, + * -ENOENT if there is no device with that number + */ +int bootdev_hunt_and_find_by_label(const char *label, struct udevice **devp, + int *method_flagsp); + +/** + * bootdev_next_label() - Move to the next bootdev in the label sequence + * + * Looks through the remaining labels until it finds one that matches a bootdev. + * Bootdev scanners are used as needed. For example a label "mmc1" results in + * running the "mmc" bootdrv. + * + * @iter: Interation info, containing iter->cur_label + * @devp: New bootdev found, if any was found + * @method_flagsp: If non-NULL, returns any flags implied by the label + * (enum bootflow_meth_flags_t), 0 if none + * Returns 0 if OK, -ENODEV if no bootdev was found + */ +int bootdev_next_label(struct bootflow_iter *iter, struct udevice **devp, + int *method_flagsp); + +/** + * bootdev_next_prio() - Find the next bootdev in priority order + * + * This moves @devp to the next bootdev with the current priority. If there is + * none, then it moves to the next priority and scans for new bootdevs there. + * + * @iter: Interation info, containing iter->cur_prio + * @devp: On entry this is the previous bootdev that was considered. On exit + * this is the new bootdev, if any was found + * Returns 0 on success (*devp is updated), -ENODEV if there are no more + * bootdevs at any priority + */ +int bootdev_next_prio(struct bootflow_iter *iter, struct udevice **devp); + +#if CONFIG_IS_ENABLED(BOOTSTD) +/** + * bootdev_setup_for_dev() - Bind a new bootdev device (deprecated) + * + * Please use bootdev_setup_for_sibling_blk() instead since it supports multiple + * (child) block devices for each media device. + * + * Creates a bootdev device as a child of @parent. This should be called from + * the driver's bind() method or its uclass' post_bind() method. + * + * If a child bootdev already exists, this function does nothing + * + * @parent: Parent device (e.g. MMC or Ethernet) + * @drv_name: Name of bootdev driver to bind + * Return: 0 if OK, -ve on error + */ +int bootdev_setup_for_dev(struct udevice *parent, const char *drv_name); + +#if CONFIG_IS_ENABLED(BOOTSTD) +/** + * bootdev_setup_for_sibling_blk() - Bind a new bootdev device for a blk device + * + * Creates a bootdev device as a sibling of @blk. This should be called from + * the driver's bind() method or its uclass' post_bind() method, at the same + * time as the bould device is bound + * + * If a device of the same name already exists, this function does nothing + * + * @parent: Parent device (e.g. MMC or Ethernet) + * @drv_name: Name of bootdev driver to bind + * Return: 0 if OK, -ve on error + */ +int bootdev_setup_for_sibling_blk(struct udevice *blk, const char *drv_name); +#else +static int bootdev_setup_for_sibling_blk(struct udevice *blk, + const char *drv_name) +{ + return 0; +} +#endif + +/** + * bootdev_get_sibling_blk() - Locate the block device for a bootdev + * + * @dev: bootdev to check + * @blkp: returns associated block device + * Return: 0 if OK, -EINVAL if @dev is not a bootdev device, other -ve on other + * error + */ +int bootdev_get_sibling_blk(struct udevice *dev, struct udevice **blkp); + +/** + * bootdev_get_from_blk() - Get the bootdev given a block device + * + * @blk: Block device to check + * @bootdebp: Returns the bootdev found, if any + * Return 0 if OK, -ve on error + */ +int bootdev_get_from_blk(struct udevice *blk, struct udevice **bootdevp); + +/** + * bootdev_unbind_dev() - Unbind a bootdev device + * + * Remove and unbind a bootdev device which is a child of @parent. This should + * be called from the driver's unbind() method or its uclass' post_bind() + * method. + * + * @parent: Parent device (e.g. MMC or Ethernet) + * Return: 0 if OK, -ve on error + */ +int bootdev_unbind_dev(struct udevice *parent); +#else +static inline int bootdev_setup_for_dev(struct udevice *parent, + const char *drv_name) +{ + return 0; +} + +static inline int bootdev_setup_for_sibling_blk(struct udevice *blk, + const char *drv_name) +{ + return 0; +} + +static inline int bootdev_unbind_dev(struct udevice *parent) +{ + return 0; +} +#endif + +#endif |