xref: /rk3399_rockchip-uboot/arch/arm/mach-rockchip/spl-boot-order.c (revision 01b8c4d110abb0dcbe36dc5b6b10d93b2b8e2667)
1 /*
2  * (C) Copyright 2017 Theobroma Systems Design und Consulting GmbH
3  *
4  * SPDX-License-Identifier:     GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <mmc.h>
10 #include <nand.h>
11 #include <spl.h>
12 
13 #if CONFIG_IS_ENABLED(OF_CONTROL) && ! CONFIG_IS_ENABLED(OF_PLATDATA)
14 /**
15  * spl_node_to_boot_device() - maps from a DT-node to a SPL boot device
16  * @node:	of_offset of the node
17  *
18  * The SPL framework uses BOOT_DEVICE_... constants to identify its boot
19  * sources.  These may take on a device-specific meaning, depending on
20  * what nodes are enabled in a DTS (e.g. BOOT_DEVICE_MMC1 may refer to
21  * different controllers/block-devices, depending on which SD/MMC controllers
22  * are enabled in any given DTS).  This function maps from a DT-node back
23  * onto a BOOT_DEVICE_... constant, considering the currently active devices.
24  *
25  * Returns
26  *   -ENOENT, if no device matching the node could be found
27  *   -ENOSYS, if the device matching the node can not be mapped onto a
28  *            SPL boot device (e.g. the third MMC device)
29  *   -1, for unspecified failures
30  *   a positive integer (from the BOOT_DEVICE_... family) on succes.
31  */
32 static int spl_node_to_boot_device(int node)
33 {
34 	struct udevice *parent;
35 
36 	/*
37 	 * This should eventually move into the SPL code, once SPL becomes
38 	 * aware of the block-device layer.  Until then (and to avoid unneeded
39 	 * delays in getting this feature out, it lives at the board-level).
40 	 */
41 	if (!uclass_get_device_by_of_offset(UCLASS_MMC, node, &parent)) {
42 		struct udevice *dev;
43 		struct blk_desc *desc = NULL;
44 
45 		for (device_find_first_child(parent, &dev);
46 		     dev;
47 		     device_find_next_child(&dev)) {
48 			if (device_get_uclass_id(dev) == UCLASS_BLK) {
49 				desc = dev_get_uclass_platdata(dev);
50 				break;
51 			}
52 		}
53 
54 		if (!desc)
55 			return -ENOENT;
56 
57 		switch (desc->devnum) {
58 		case 0:
59 			return BOOT_DEVICE_MMC1;
60 		case 1:
61 			return BOOT_DEVICE_MMC2;
62 		default:
63 			return -ENOSYS;
64 		}
65 	}
66 
67 	/*
68 	 * SPL doesn't differentiate SPI flashes, so we keep the detection
69 	 * brief and inaccurate... hopefully, the common SPL layer can be
70 	 * extended with awareness of the BLK layer (and matching OF_CONTROL)
71 	 * soon.
72 	 */
73 	if (!uclass_get_device_by_of_offset(UCLASS_SPI_FLASH, node, &parent))
74 #ifndef CONFIG_SPL_MTD_SUPPORT
75 		return BOOT_DEVICE_SPI;
76 #else
77 		return BOOT_DEVICE_MTD_BLK_SPI_NOR;
78 
79 	if (!uclass_get_device_by_of_offset(UCLASS_MTD, node, &parent)) {
80 		struct udevice *dev;
81 		struct blk_desc *desc = NULL;
82 
83 		for (device_find_first_child(parent, &dev);
84 		     dev;
85 		     device_find_next_child(&dev)) {
86 			if (device_get_uclass_id(dev) == UCLASS_BLK) {
87 				desc = dev_get_uclass_platdata(dev);
88 				break;
89 			}
90 		}
91 
92 		if (!desc)
93 			return -ENOENT;
94 
95 		switch (desc->devnum) {
96 		case 0:
97 			return BOOT_DEVICE_MTD_BLK_NAND;
98 		case 1:
99 			return BOOT_DEVICE_MTD_BLK_SPI_NAND;
100 		default:
101 			return -ENOSYS;
102 		}
103 	}
104 #endif
105 
106 	return -1;
107 }
108 
109 /**
110  * board_spl_was_booted_from() - retrieves the of-path the SPL was loaded from
111  *
112  * To support a 'same-as-spl' specification in the search-order for the next
113  * stage, we need a SoC- or board-specific way to handshake with what 'came
114  * before us' (either a BROM or TPL stage) and map the info retrieved onto
115  * a OF path.
116  *
117  * Returns
118  *   NULL, on failure or if the device could not be identified
119  *   a of_path (a string), on success
120  */
121 __weak const char *board_spl_was_booted_from(void)
122 {
123 	debug("%s: no support for 'same-as-spl' for this board\n", __func__);
124 	return NULL;
125 }
126 
127 void board_boot_order(u32 *spl_boot_list)
128 {
129 	const void *blob = gd->fdt_blob;
130 	int chosen_node = fdt_path_offset(blob, "/chosen");
131 	int idx = 0;
132 	int elem;
133 	int boot_device;
134 	int node;
135 	const char *conf;
136 
137 	if (chosen_node < 0) {
138 		debug("%s: /chosen not found, using spl_boot_device()\n",
139 		      __func__);
140 		spl_boot_list[0] = spl_boot_device();
141 		return;
142 	}
143 
144 	for (elem = 0;
145 	     (conf = fdt_stringlist_get(blob, chosen_node,
146 					"u-boot,spl-boot-order", elem, NULL));
147 	     elem++) {
148 		const char *alias;
149 
150 		/* Handle the case of 'same device the SPL was loaded from' */
151 		if (strncmp(conf, "same-as-spl", 11) == 0) {
152 			conf = board_spl_was_booted_from();
153 			if (!conf)
154 				continue;
155 		}
156 
157 		/* First check if the list element is an alias */
158 		alias = fdt_get_alias(blob, conf);
159 		if (alias)
160 			conf = alias;
161 
162 		/* Try to resolve the config item (or alias) as a path */
163 		node = fdt_path_offset(blob, conf);
164 		if (node < 0) {
165 			debug("%s: could not find %s in FDT", __func__, conf);
166 			continue;
167 		}
168 
169 		/* Try to map this back onto SPL boot devices */
170 		boot_device = spl_node_to_boot_device(node);
171 		if (boot_device < 0) {
172 			debug("%s: could not map node @%x to a boot-device\n",
173 			      __func__, node);
174 			continue;
175 		}
176 
177 		spl_boot_list[idx++] = boot_device;
178 	}
179 
180 	/* If we had no matches, fall back to spl_boot_device */
181 	if (idx == 0)
182 		spl_boot_list[0] = spl_boot_device();
183 }
184 #endif
185