1 files changed, 275 insertions, 0 deletions
diff --git a/include/bootdev.h b/include/bootdev.h
new file mode 100644
index 0000000000..9fc219839f
--- /dev/null
+++ b/include/bootdev.h
@@ -0,0 +1,275 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2021 Google LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#ifndef __bootdev_h
+#define __bootdev_h
+
+#include <linux/list.h>
+
+struct bootflow;
+struct bootflow_iter;
+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
+ */
+enum bootdev_prio_t {
+	BOOTDEVP_0_INTERNAL_FAST	= 10,
+	BOOTDEVP_1_INTERNAL_SLOW	= 20,
+	BOOTDEVP_2_SCAN_FAST		= 30,
+	BOOTDEVP_3_SCAN_SLOW		= 40,
+	BOOTDEVP_4_NET_BASE		= 50,
+	BOOTDEVP_5_NET_FALLBACK		= 60,
+	BOOTDEVP_6_SYSTEM		= 70,
+
+	BOOTDEVP_COUNT,
+};
+
+/**
+ * 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)
+ *
+ * @bootflows: List of available bootflows for this bootdev
+ * @piro: Priority of this bootdev
+ */
+struct bootdev_uc_plat {
+	struct list_head bootflow_head;
+	enum bootdev_prio_t prio;
+};
+
+/** struct bootdev_ops - Operations for the bootdev uclass */
+struct bootdev_ops {
+	/**
+	 * get_bootflow() - get a 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_clear_bootflows() - Clear bootflows from a bootdev
+ *
+ * Each bootdev maintains a list of discovered bootflows. This provides a
+ * way to clear it. These bootflows are removed from the global list too.
+ *
+ * @dev: bootdev device to update
+ */
+void bootdev_clear_bootflows(struct udevice *dev);
+
+/**
+ * bootdev_add_bootflow() - Add a bootflow to the bootdev's list
+ *
+ * All fields in @bflow must be set up. Note that @bflow->dev is used to add the
+ * bootflow to that device.
+ *
+ * @dev: Bootdevice device to add to
+ * @bflow: Bootflow to add. Note that fields within bflow must be allocated
+ *	since this function takes over ownership of these. This functions makes
+ *	a copy of @bflow itself (without allocating its fields again), so the
+ *	caller must dispose of the memory used by the @bflow pointer itself
+ * Return: 0 if OK, -ENOMEM if out of memory
+ */
+int bootdev_add_bootflow(struct bootflow *bflow);
+
+/**
+ * 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)
+ * 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);
+
+/**
+ * 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
+ * Return: 0 if OK, -ve on error
+ */
+int bootdev_find_by_any(const char *name, struct udevice **devp);
+
+/**
+ * bootdev_setup_iter_order() - Set up the ordering of bootdevs to scan
+ *
+ * This sets up the ordering information in @iter, based on the priority of each
+ * bootdev and the bootdev-order property in the bootstd node
+ *
+ * If a single device is requested, no ordering is needed
+ *
+ * @iter: Iterator to update with the order
+ * @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
+ * Return: 0 if OK, -ENOENT if no bootdevs, -ENOMEM if out of memory, other -ve
+ *	on other error
+ */
+int bootdev_setup_iter_order(struct bootflow_iter *iter, struct udevice **devp);
+
+#if CONFIG_IS_ENABLED(BOOTSTD)
+/**
+ * bootdev_setup_for_dev() - Bind a new bootdev 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);
+
+/**
+ * bootdev_setup_for_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_sibling_blk(struct udevice *blk, const char *drv_name);
+
+/**
+ * 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_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_sibling_blk(struct udevice *blk,
+					    const char *drv_name)
+{
+	return 0;
+}
+
+static inline int bootdev_unbind_dev(struct udevice *parent)
+{
+	return 0;
+}
+#endif
+
+#endif