mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-26 21:13:48 +00:00
50128aeb0f
Currently, we must call cyclic_init() at some point before cyclic_register() becomes possible. That turns out to be somewhat awkward, especially with SPL, and has resulted in a watchdog callback not being registered, thus causing the board to prematurely reset. We already rely on gd->cyclic reliably being set to NULL by the asm code that clears all of gd. Now that the cyclic list is a hlist, and thus an empty list is represented by a NULL head pointer, and struct cyclic_drv has no other members, we can just as well drop a level of indirection and put the hlist_head directly in struct global_data. This doesn't increase the size of struct global_data, gets rid of an early malloc(), and generates slightly smaller code. But primarily, this avoids having to call cyclic_init() early; the cyclic infrastructure is simply ready to register callbacks as soon as we enter C code. We can still end up with schedule() being called from asm very early, so we still need to check that gd itself has been properly initialized [*], but once it has, gd->cyclic_list is perfectly fine to access, and will just be an empty list. As for cyclic_uninit(), it was never really the opposite of cyclic_init() since it didn't free the struct cyclic_drv nor set gd->cyclic to NULL. Rename it to cyclic_unregister_all() and use that in test/, and also insert a call at the end of the board_init_f sequence so that gd->cyclic_list is a fresh empty list before we enter board_init_r(). A small piece of ugliness is that I had to add a cast in cyclic_get_list() to silence a "discards 'volatile' qualifier" warning, but that is completely equivalent to the existing handling of the uclass_root_s list_head member. [*] I'm not really sure where we guarantee that the register used for gd contains 0 until it gets explicitly initialized, but that must be the case, otherwise testing gd for being NULL would not make much sense. Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Reviewed-by: Stefan Roese <sr@denx.de> Tested-by: Stefan Roese <sr@denx.de> Tested-by: Tim Harvey <tharvey@gateworks.com> # imx8mm-venice-*
127 lines
3.1 KiB
C
127 lines
3.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0+ */
|
|
/*
|
|
* A general-purpose cyclic execution infrastructure, to allow "small"
|
|
* (run-time wise) functions to be executed at a specified frequency.
|
|
* Things like LED blinking or watchdog triggering are examples for such
|
|
* tasks.
|
|
*
|
|
* Copyright (C) 2022 Stefan Roese <sr@denx.de>
|
|
*/
|
|
|
|
#ifndef __cyclic_h
|
|
#define __cyclic_h
|
|
|
|
#include <linux/list.h>
|
|
#include <asm/types.h>
|
|
|
|
/**
|
|
* struct cyclic_info - Information about cyclic execution function
|
|
*
|
|
* @func: Function to call periodically
|
|
* @ctx: Context pointer to get passed to this function
|
|
* @name: Name of the cyclic function, e.g. shown in the commands
|
|
* @delay_ns: Delay is ns after which this function shall get executed
|
|
* @start_time_us: Start time in us, when this function started its execution
|
|
* @cpu_time_us: Total CPU time of this function
|
|
* @run_cnt: Counter of executions occurances
|
|
* @next_call: Next time in us, when the function shall be executed again
|
|
* @list: List node
|
|
* @already_warned: Flag that we've warned about exceeding CPU time usage
|
|
*/
|
|
struct cyclic_info {
|
|
void (*func)(void *ctx);
|
|
void *ctx;
|
|
char *name;
|
|
uint64_t delay_us;
|
|
uint64_t start_time_us;
|
|
uint64_t cpu_time_us;
|
|
uint64_t run_cnt;
|
|
uint64_t next_call;
|
|
struct hlist_node list;
|
|
bool already_warned;
|
|
};
|
|
|
|
/** Function type for cyclic functions */
|
|
typedef void (*cyclic_func_t)(void *ctx);
|
|
|
|
#if defined(CONFIG_CYCLIC)
|
|
/**
|
|
* cyclic_register - Register a new cyclic function
|
|
*
|
|
* @func: Function to call periodically
|
|
* @delay_us: Delay is us after which this function shall get executed
|
|
* @name: Cyclic function name/id
|
|
* @ctx: Context to pass to the function
|
|
* @return: pointer to cyclic_struct if OK, NULL on error
|
|
*/
|
|
struct cyclic_info *cyclic_register(cyclic_func_t func, uint64_t delay_us,
|
|
const char *name, void *ctx);
|
|
|
|
/**
|
|
* cyclic_unregister - Unregister a cyclic function
|
|
*
|
|
* @cyclic: Pointer to cyclic_struct of the function that shall be removed
|
|
* @return: 0 if OK, -ve on error
|
|
*/
|
|
int cyclic_unregister(struct cyclic_info *cyclic);
|
|
|
|
/**
|
|
* cyclic_unregister_all() - Clean up cyclic functions
|
|
*
|
|
* This removes all cyclic functions
|
|
*/
|
|
int cyclic_unregister_all(void);
|
|
|
|
/**
|
|
* cyclic_get_list() - Get cyclic list pointer
|
|
*
|
|
* Return the cyclic list pointer
|
|
*
|
|
* @return: pointer to cyclic_list
|
|
*/
|
|
struct hlist_head *cyclic_get_list(void);
|
|
|
|
/**
|
|
* cyclic_run() - Interate over all registered cyclic functions
|
|
*
|
|
* Interate over all registered cyclic functions and if the it's function
|
|
* needs to be executed, then call into these registered functions.
|
|
*/
|
|
void cyclic_run(void);
|
|
|
|
/**
|
|
* schedule() - Schedule all potentially waiting tasks
|
|
*
|
|
* Basically a wrapper for cyclic_run(), pontentially enhanced by some
|
|
* other parts, that need to get handled periodically.
|
|
*/
|
|
void schedule(void);
|
|
#else
|
|
static inline struct cyclic_info *cyclic_register(cyclic_func_t func,
|
|
uint64_t delay_us,
|
|
const char *name,
|
|
void *ctx)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline int cyclic_unregister(struct cyclic_info *cyclic)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void cyclic_run(void)
|
|
{
|
|
}
|
|
|
|
static inline void schedule(void)
|
|
{
|
|
}
|
|
|
|
static inline int cyclic_unregister_all(void)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
#endif
|