xref: /rk3399_rockchip-uboot/arch/arm/mach-rockchip/spl-boot-order.c (revision d0ff3d454829105c81afe7f5d8c79e0d3d18c1a2)
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 
33 static int spl_node_to_boot_device(int node)
34 {
35 	struct udevice *parent;
36 
37 	if (!uclass_get_device_by_of_offset(UCLASS_SPI, node, &parent))
38 		return BOOT_DEVICE_MTD_BLK_SPI_NAND;
39 
40 #ifdef CONFIG_SPL_NAND_SUPPORT
41 	if (!rk_nand_init())
42 		return BOOT_DEVICE_NAND;
43 #endif
44 
45 	/*
46 	 * This should eventually move into the SPL code, once SPL becomes
47 	 * aware of the block-device layer.  Until then (and to avoid unneeded
48 	 * delays in getting this feature out, it lives at the board-level).
49 	 */
50 	if (!uclass_get_device_by_of_offset(UCLASS_MMC, node, &parent)) {
51 		struct udevice *dev;
52 		struct blk_desc *desc = NULL;
53 
54 		for (device_find_first_child(parent, &dev);
55 		     dev;
56 		     device_find_next_child(&dev)) {
57 			if (device_get_uclass_id(dev) == UCLASS_BLK) {
58 				desc = dev_get_uclass_platdata(dev);
59 				break;
60 			}
61 		}
62 
63 		if (!desc)
64 			return -ENOENT;
65 
66 		switch (desc->devnum) {
67 		case 0:
68 			return BOOT_DEVICE_MMC1;
69 		case 1:
70 			return BOOT_DEVICE_MMC2;
71 		default:
72 			return -ENOSYS;
73 		}
74 	}
75 
76 	/*
77 	 * SPL doesn't differentiate SPI flashes, so we keep the detection
78 	 * brief and inaccurate... hopefully, the common SPL layer can be
79 	 * extended with awareness of the BLK layer (and matching OF_CONTROL)
80 	 * soon.
81 	 */
82 	if (!uclass_get_device_by_of_offset(UCLASS_SPI_FLASH, node, &parent))
83 		return BOOT_DEVICE_SPI;
84 
85 	return -1;
86 }
87 
88 /**
89  * board_spl_was_booted_from() - retrieves the of-path the SPL was loaded from
90  *
91  * To support a 'same-as-spl' specification in the search-order for the next
92  * stage, we need a SoC- or board-specific way to handshake with what 'came
93  * before us' (either a BROM or TPL stage) and map the info retrieved onto
94  * a OF path.
95  *
96  * Returns
97  *   NULL, on failure or if the device could not be identified
98  *   a of_path (a string), on success
99  */
100 __weak const char *board_spl_was_booted_from(void)
101 {
102 	debug("%s: no support for 'same-as-spl' for this board\n", __func__);
103 	return NULL;
104 }
105 
106 void board_boot_order(u32 *spl_boot_list)
107 {
108 	const void *blob = gd->fdt_blob;
109 	int chosen_node = fdt_path_offset(blob, "/chosen");
110 	int idx = 0;
111 	int elem;
112 	int boot_device;
113 	int node;
114 	const char *conf;
115 
116 	if (chosen_node < 0) {
117 		debug("%s: /chosen not found, using spl_boot_device()\n",
118 		      __func__);
119 		spl_boot_list[0] = spl_boot_device();
120 		return;
121 	}
122 
123 	for (elem = 0;
124 	     (conf = fdt_stringlist_get(blob, chosen_node,
125 					"u-boot,spl-boot-order", elem, NULL));
126 	     elem++) {
127 		const char *alias;
128 
129 		/* Handle the case of 'same device the SPL was loaded from' */
130 		if (strncmp(conf, "same-as-spl", 11) == 0) {
131 			conf = board_spl_was_booted_from();
132 			if (!conf)
133 				continue;
134 		}
135 
136 		/* First check if the list element is an alias */
137 		alias = fdt_get_alias(blob, conf);
138 		if (alias)
139 			conf = alias;
140 
141 		/* Try to resolve the config item (or alias) as a path */
142 		node = fdt_path_offset(blob, conf);
143 		if (node < 0) {
144 			debug("%s: could not find %s in FDT", __func__, conf);
145 			continue;
146 		}
147 
148 		/* Try to map this back onto SPL boot devices */
149 		boot_device = spl_node_to_boot_device(node);
150 		if (boot_device < 0) {
151 			debug("%s: could not map node @%x to a boot-device\n",
152 			      __func__, node);
153 			continue;
154 		}
155 
156 		spl_boot_list[idx++] = boot_device;
157 	}
158 
159 	/* If we had no matches, fall back to spl_boot_device */
160 	if (idx == 0)
161 		spl_boot_list[0] = spl_boot_device();
162 }
163 #endif
164