mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-05 11:00:15 +00:00
c81b460c86
Add a command to show the available events. Signed-off-by: Simon Glass <sjg@chromium.org>
210 lines
4.7 KiB
C
210 lines
4.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0+ */
|
|
/*
|
|
* Events provide a general-purpose way to react to / subscribe to changes
|
|
* within U-Boot
|
|
*
|
|
* Copyright 2021 Google LLC
|
|
* Written by Simon Glass <sjg@chromium.org>
|
|
*/
|
|
|
|
#ifndef __event_h
|
|
#define __event_h
|
|
|
|
/**
|
|
* enum event_t - Types of events supported by U-Boot
|
|
*
|
|
* @EVT_DM_PRE_PROBE: Device is about to be probed
|
|
*/
|
|
enum event_t {
|
|
EVT_NONE,
|
|
EVT_TEST,
|
|
|
|
/* Events related to driver model */
|
|
EVT_DM_POST_INIT,
|
|
EVT_DM_PRE_PROBE,
|
|
EVT_DM_POST_PROBE,
|
|
EVT_DM_PRE_REMOVE,
|
|
EVT_DM_POST_REMOVE,
|
|
|
|
/* Init hooks */
|
|
EVT_MISC_INIT_F,
|
|
|
|
EVT_COUNT
|
|
};
|
|
|
|
union event_data {
|
|
/**
|
|
* struct event_data_test - test data
|
|
*
|
|
* @signal: A value to update the state with
|
|
*/
|
|
struct event_data_test {
|
|
int signal;
|
|
} test;
|
|
|
|
/**
|
|
* struct event_dm - driver model event
|
|
*
|
|
* @dev: Device this event relates to
|
|
*/
|
|
struct event_dm {
|
|
struct udevice *dev;
|
|
} dm;
|
|
};
|
|
|
|
/**
|
|
* struct event - an event that can be sent and received
|
|
*
|
|
* @type: Event type
|
|
* @data: Data for this particular event
|
|
*/
|
|
struct event {
|
|
enum event_t type;
|
|
union event_data data;
|
|
};
|
|
|
|
/** Function type for event handlers */
|
|
typedef int (*event_handler_t)(void *ctx, struct event *event);
|
|
|
|
/**
|
|
* struct evspy_info - information about an event spy
|
|
*
|
|
* @func: Function to call when the event is activated (must be first)
|
|
* @type: Event type
|
|
* @id: Event id string
|
|
*/
|
|
struct evspy_info {
|
|
event_handler_t func;
|
|
enum event_t type;
|
|
#if CONFIG_IS_ENABLED(EVENT_DEBUG)
|
|
const char *id;
|
|
#endif
|
|
};
|
|
|
|
/* Declare a new event spy */
|
|
#if CONFIG_IS_ENABLED(EVENT_DEBUG)
|
|
#define _ESPY_REC(_type, _func) { _func, _type, #_func, }
|
|
#else
|
|
#define _ESPY_REC(_type, _func) { _func, _type, }
|
|
#endif
|
|
|
|
static inline const char *event_spy_id(struct evspy_info *spy)
|
|
{
|
|
#if CONFIG_IS_ENABLED(EVENT_DEBUG)
|
|
return spy->id;
|
|
#else
|
|
return "?";
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* It seems that LTO will drop list entries if it decides they are not used,
|
|
* although the conditions that cause this are unclear.
|
|
*
|
|
* The example found is the following:
|
|
*
|
|
* static int sandbox_misc_init_f(void *ctx, struct event *event)
|
|
* {
|
|
* return sandbox_early_getopt_check();
|
|
* }
|
|
* EVENT_SPY(EVT_MISC_INIT_F, sandbox_misc_init_f);
|
|
*
|
|
* where EVENT_SPY uses ll_entry_declare()
|
|
*
|
|
* In this case, LTO decides to drop the sandbox_misc_init_f() function
|
|
* (which is fine) but then drops the linker-list entry too. This means
|
|
* that the code no longer works, in this case sandbox no-longer checks its
|
|
* command-line arguments properly.
|
|
*
|
|
* Without LTO, the KEEP() command in the .lds file is enough to keep the
|
|
* entry around. But with LTO it seems that the entry has already been
|
|
* dropped before the link script is considered.
|
|
*
|
|
* The only solution I can think of is to mark linker-list entries as 'used'
|
|
* using an attribute. This should be safe, since we don't actually want to drop
|
|
* any of these. However this does slightly limit LTO's optimisation choices.
|
|
*/
|
|
#define EVENT_SPY(_type, _func) \
|
|
static __attribute__((used)) ll_entry_declare(struct evspy_info, \
|
|
_type, evspy_info) = \
|
|
_ESPY_REC(_type, _func)
|
|
|
|
/**
|
|
* event_register - register a new spy
|
|
*
|
|
* @id: Spy ID
|
|
* @type: Event type to subscribe to
|
|
* @func: Function to call when the event is sent
|
|
* @ctx: Context to pass to the function
|
|
* @return 0 if OK, -ve on error
|
|
*/
|
|
int event_register(const char *id, enum event_t type, event_handler_t func,
|
|
void *ctx);
|
|
|
|
/** event_show_spy_list( - Show a list of event spies */
|
|
void event_show_spy_list(void);
|
|
|
|
#if CONFIG_IS_ENABLED(EVENT)
|
|
/**
|
|
* event_notify() - notify spies about an event
|
|
*
|
|
* It is possible to pass in union event_data here but that may not be
|
|
* convenient if the data is elsewhere, or is one of the members of the union.
|
|
* So this uses a void * for @data, with a separate @size.
|
|
*
|
|
* @type: Event type
|
|
* @data: Event data to be sent (e.g. union_event_data)
|
|
* @size: Size of data in bytes
|
|
* @return 0 if OK, -ve on error
|
|
*/
|
|
int event_notify(enum event_t type, void *data, int size);
|
|
|
|
/**
|
|
* event_notify_null() - notify spies about an event
|
|
*
|
|
* Data is NULL and the size is 0
|
|
*
|
|
* @type: Event type
|
|
* @return 0 if OK, -ve on error
|
|
*/
|
|
int event_notify_null(enum event_t type);
|
|
#else
|
|
static inline int event_notify(enum event_t type, void *data, int size)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int event_notify_null(enum event_t type)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
#if CONFIG_IS_ENABLED(EVENT_DYNAMIC)
|
|
/**
|
|
* event_uninit() - Clean up dynamic events
|
|
*
|
|
* This removes all dynamic event handlers
|
|
*/
|
|
int event_uninit(void);
|
|
|
|
/**
|
|
* event_uninit() - Set up dynamic events
|
|
*
|
|
* Init a list of dynamic event handlers, so that these can be added as
|
|
* needed
|
|
*/
|
|
int event_init(void);
|
|
#else
|
|
static inline int event_uninit(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int event_init(void)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
#endif
|