blob: 843998dfdcb8d256bbb5966761273e40805646c6 [file] [log] [blame]
/*
* (C) Copyright 2017 Theobroma Systems Design und Consulting GmbH
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <mmc.h>
#include <spl.h>
#if CONFIG_IS_ENABLED(OF_CONTROL)
/**
* spl_node_to_boot_device() - maps from a DT-node to a SPL boot device
* @node: of_offset of the node
*
* The SPL framework uses BOOT_DEVICE_... constants to identify its boot
* sources. These may take on a device-specific meaning, depending on
* what nodes are enabled in a DTS (e.g. BOOT_DEVICE_MMC1 may refer to
* different controllers/block-devices, depending on which SD/MMC controllers
* are enabled in any given DTS). This function maps from a DT-node back
* onto a BOOT_DEVICE_... constant, considering the currently active devices.
*
* Returns
* -ENOENT, if no device matching the node could be found
* -ENOSYS, if the device matching the node can not be mapped onto a
* SPL boot device (e.g. the third MMC device)
* -1, for unspecified failures
* a positive integer (from the BOOT_DEVICE_... family) on succes.
*/
static int spl_node_to_boot_device(int node)
{
struct udevice *parent;
/*
* This should eventually move into the SPL code, once SPL becomes
* aware of the block-device layer. Until then (and to avoid unneeded
* delays in getting this feature out, it lives at the board-level).
*/
if (!uclass_get_device_by_of_offset(UCLASS_MMC, node, &parent)) {
struct udevice *dev;
struct blk_desc *desc = NULL;
for (device_find_first_child(parent, &dev);
dev;
device_find_next_child(&dev)) {
if (device_get_uclass_id(dev) == UCLASS_BLK) {
desc = dev_get_uclass_platdata(dev);
break;
}
}
if (!desc)
return -ENOENT;
switch (desc->devnum) {
case 0:
return BOOT_DEVICE_MMC1;
case 1:
return BOOT_DEVICE_MMC2;
default:
return -ENOSYS;
}
}
/*
* SPL doesn't differentiate SPI flashes, so we keep the detection
* brief and inaccurate... hopefully, the common SPL layer can be
* extended with awareness of the BLK layer (and matching OF_CONTROL)
* soon.
*/
if (!uclass_get_device_by_of_offset(UCLASS_SPI_FLASH, node, &parent))
return BOOT_DEVICE_SPI;
return -1;
}
/**
* board_spl_was_booted_from() - retrieves the of-path the SPL was loaded from
*
* To support a 'same-as-spl' specification in the search-order for the next
* stage, we need a SoC- or board-specific way to handshake with what 'came
* before us' (either a BROM or TPL stage) and map the info retrieved onto
* a OF path.
*
* Returns
* NULL, on failure or if the device could not be identified
* a of_path (a string), on success
*/
__weak const char *board_spl_was_booted_from(void)
{
debug("%s: no support for 'same-as-spl' for this board\n", __func__);
return NULL;
}
void board_boot_order(u32 *spl_boot_list)
{
const void *blob = gd->fdt_blob;
int chosen_node = fdt_path_offset(blob, "/chosen");
int idx = 0;
int elem;
int boot_device;
int node;
const char *conf;
if (chosen_node < 0) {
debug("%s: /chosen not found, using spl_boot_device()\n",
__func__);
spl_boot_list[0] = spl_boot_device();
return;
}
for (elem = 0;
(conf = fdt_stringlist_get(blob, chosen_node,
"u-boot,spl-boot-order", elem, NULL));
elem++) {
const char *alias;
/* Handle the case of 'same device the SPL was loaded from' */
if (strncmp(conf, "same-as-spl", 11) == 0) {
conf = board_spl_was_booted_from();
if (!conf)
continue;
}
/* First check if the list element is an alias */
alias = fdt_get_alias(blob, conf);
if (alias)
conf = alias;
/* Try to resolve the config item (or alias) as a path */
node = fdt_path_offset(blob, conf);
if (node < 0) {
debug("%s: could not find %s in FDT", __func__, conf);
continue;
}
/* Try to map this back onto SPL boot devices */
boot_device = spl_node_to_boot_device(node);
if (boot_device < 0) {
debug("%s: could not map node @%x to a boot-device\n",
__func__, node);
continue;
}
spl_boot_list[idx++] = boot_device;
}
/* If we had no matches, fall back to spl_boot_device */
if (idx == 0)
spl_boot_list[0] = spl_boot_device();
}
#endif