u-boot/include/dm/root.h
Simon Glass 2f11cd9121 dm: core: Handle global_data moving in SPL
When CONFIG_SPL_STACK_R is enabled, and spl_init() is called before
board_init_r(), spl_relocate_stack_gd() will move global_data to a new
place in memory. This affects driver model since it uses a list for the
uclasses. Unless this is updated the list will become invalid. When
looking for a non-existent uclass, such as when adding a new one, the loop
in uclass_find() may continue forever, thus causing a hang.

Add a function to correct this rather obscure bug.

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-12-02 20:53:19 -07:00

118 lines
3.4 KiB
C

/*
* Copyright (c) 2013 Google, Inc
*
* (C) Copyright 2012
* Pavel Herrmann <morpheus.ibis@gmail.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef _DM_ROOT_H_
#define _DM_ROOT_H_
struct udevice;
/**
* dm_root() - Return pointer to the top of the driver tree
*
* This function returns pointer to the root node of the driver tree,
*
* @return pointer to root device, or NULL if not inited yet
*/
struct udevice *dm_root(void);
struct global_data;
/**
* dm_fixup_for_gd_move() - Handle global_data moving to a new place
*
* The uclass list is part of global_data. Due to the way lists work, moving
* the list will cause it to become invalid. This function fixes that up so
* that the uclass list will work correctly.
*/
void dm_fixup_for_gd_move(struct global_data *new_gd);
/**
* dm_scan_platdata() - Scan all platform data and bind drivers
*
* This scans all available platdata and creates drivers for each
*
* @pre_reloc_only: If true, bind only drivers with the DM_FLAG_PRE_RELOC
* flag. If false bind all drivers.
* @return 0 if OK, -ve on error
*/
int dm_scan_platdata(bool pre_reloc_only);
/**
* dm_scan_fdt() - Scan the device tree and bind drivers
*
* This scans the device tree and creates a driver for each node. Only
* the top-level subnodes are examined.
*
* @blob: Pointer to device tree blob
* @pre_reloc_only: If true, bind only drivers with the DM_FLAG_PRE_RELOC
* flag. If false bind all drivers.
* @return 0 if OK, -ve on error
*/
int dm_scan_fdt(const void *blob, bool pre_reloc_only);
/**
* dm_scan_fdt_node() - Scan the device tree and bind drivers for a node
*
* This scans the subnodes of a device tree node and and creates a driver
* for each one.
*
* @parent: Parent device for the devices that will be created
* @blob: Pointer to device tree blob
* @offset: Offset of node to scan
* @pre_reloc_only: If true, bind only drivers with the DM_FLAG_PRE_RELOC
* flag. If false bind all drivers.
* @return 0 if OK, -ve on error
*/
int dm_scan_fdt_node(struct udevice *parent, const void *blob, int offset,
bool pre_reloc_only);
/**
* dm_scan_other() - Scan for other devices
*
* Some devices may not be visible to Driver Model. This weak function can
* be provided by boards which wish to create their own devices
* programmaticaly. They should do this by calling device_bind() on each
* device.
*
* @pre_reloc_only: If true, bind only drivers with the DM_FLAG_PRE_RELOC
* flag. If false bind all drivers.
*/
int dm_scan_other(bool pre_reloc_only);
/**
* dm_init_and_scan() - Initialise Driver Model structures and scan for devices
*
* This function initialises the roots of the driver tree and uclass trees,
* then scans and binds available devices from platform data and the FDT.
* This calls dm_init() to set up Driver Model structures.
*
* @pre_reloc_only: If true, bind only drivers with the DM_FLAG_PRE_RELOC
* flag. If false bind all drivers.
* @return 0 if OK, -ve on error
*/
int dm_init_and_scan(bool pre_reloc_only);
/**
* dm_init() - Initialise Driver Model structures
*
* This function will initialize roots of driver tree and class tree.
* This needs to be called before anything uses the DM
*
* @return 0 if OK, -ve on error
*/
int dm_init(void);
/**
* dm_uninit - Uninitialise Driver Model structures
*
* All devices will be removed and unbound
* @return 0 if OK, -ve on error
*/
int dm_uninit(void);
#endif