1 // SPDX-License-Identifier: GPL-2.0+
3 * (C) Copyright 2017 Theobroma Systems Design und Consulting GmbH
11 #if CONFIG_IS_ENABLED(OF_LIBFDT)
13 * spl_node_to_boot_device() - maps from a DT-node to a SPL boot device
14 * @node: of_offset of the node
16 * The SPL framework uses BOOT_DEVICE_... constants to identify its boot
17 * sources. These may take on a device-specific meaning, depending on
18 * what nodes are enabled in a DTS (e.g. BOOT_DEVICE_MMC1 may refer to
19 * different controllers/block-devices, depending on which SD/MMC controllers
20 * are enabled in any given DTS). This function maps from a DT-node back
21 * onto a BOOT_DEVICE_... constant, considering the currently active devices.
24 * -ENOENT, if no device matching the node could be found
25 * -ENOSYS, if the device matching the node can not be mapped onto a
26 * SPL boot device (e.g. the third MMC device)
27 * -1, for unspecified failures
28 * a positive integer (from the BOOT_DEVICE_... family) on succes.
31 static int spl_node_to_boot_device(int node)
33 struct udevice *parent;
36 * This should eventually move into the SPL code, once SPL becomes
37 * aware of the block-device layer. Until then (and to avoid unneeded
38 * delays in getting this feature out, it lives at the board-level).
40 if (!uclass_get_device_by_of_offset(UCLASS_MMC, node, &parent)) {
42 struct blk_desc *desc = NULL;
44 for (device_find_first_child(parent, &dev);
46 device_find_next_child(&dev)) {
47 if (device_get_uclass_id(dev) == UCLASS_BLK) {
48 desc = dev_get_uclass_platdata(dev);
56 switch (desc->devnum) {
58 return BOOT_DEVICE_MMC1;
60 return BOOT_DEVICE_MMC2;
64 } else if (!uclass_get_device_by_of_offset(UCLASS_SPI_FLASH, node,
66 return BOOT_DEVICE_SPI;
70 * SPL doesn't differentiate SPI flashes, so we keep the detection
71 * brief and inaccurate... hopefully, the common SPL layer can be
72 * extended with awareness of the BLK layer (and matching OF_CONTROL)
75 if (!uclass_get_device_by_of_offset(UCLASS_SPI_FLASH, node, &parent))
76 return BOOT_DEVICE_SPI;
82 * board_spl_was_booted_from() - retrieves the of-path the SPL was loaded from
84 * To support a 'same-as-spl' specification in the search-order for the next
85 * stage, we need a SoC- or board-specific way to handshake with what 'came
86 * before us' (either a BROM or TPL stage) and map the info retrieved onto
90 * NULL, on failure or if the device could not be identified
91 * a of_path (a string), on success
93 __weak const char *board_spl_was_booted_from(void)
95 debug("%s: no support for 'same-as-spl' for this board\n", __func__);
99 void board_boot_order(u32 *spl_boot_list)
101 const void *blob = gd->fdt_blob;
102 int chosen_node = fdt_path_offset(blob, "/chosen");
109 if (chosen_node < 0) {
110 debug("%s: /chosen not found, using spl_boot_device()\n",
112 spl_boot_list[0] = spl_boot_device();
117 (conf = fdt_stringlist_get(blob, chosen_node,
118 "u-boot,spl-boot-order", elem, NULL));
122 /* Handle the case of 'same device the SPL was loaded from' */
123 if (strncmp(conf, "same-as-spl", 11) == 0) {
124 conf = board_spl_was_booted_from();
129 /* First check if the list element is an alias */
130 alias = fdt_get_alias(blob, conf);
134 /* Try to resolve the config item (or alias) as a path */
135 node = fdt_path_offset(blob, conf);
137 debug("%s: could not find %s in FDT\n", __func__, conf);
141 /* Try to map this back onto SPL boot devices */
142 boot_device = spl_node_to_boot_device(node);
143 if (boot_device < 0) {
144 debug("%s: could not map node @%x to a boot-device\n",
149 spl_boot_list[idx++] = boot_device;
152 /* If we had no matches, fall back to spl_boot_device */
154 spl_boot_list[0] = spl_boot_device();