Files
opensbi/include/sbi/sbi_timer.h
Samuel Holland 4500828743 lib: sbi_timer: Call driver warm_init from SBI core
Currently, the platform's timer device is tracked in two places: the
core SBI implementation has `timer_dev`, and the FDT timer layer has
`current_driver`. The latter is used for warm initialization of the
timer device. However, this warm init is not specific to FDT-based
platforms; other platforms call exactly the same functions from the
same point in the boot sequence.

The code is simplified and made common across platforms by treating warm
init and exit as properties of the driver, not the platform. Then the
platform's only role is to select and prepare a driver during cold boot.

For now, only add a .warm_init hook, since none of the existing drivers
need an .exit hook. It could be added in the future if needed.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2024-11-05 17:29:13 +05:30

108 lines
2.8 KiB
C

/*
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2019 Western Digital Corporation or its affiliates.
*
* Authors:
* Anup Patel <anup.patel@wdc.com>
*/
#ifndef __SBI_TIMER_H__
#define __SBI_TIMER_H__
#include <sbi/sbi_types.h>
/** Timer hardware device */
struct sbi_timer_device {
/** Name of the timer operations */
char name[32];
/** Frequency of timer in HZ */
unsigned long timer_freq;
/** Get free-running timer value */
u64 (*timer_value)(void);
/** Start timer event for current HART */
void (*timer_event_start)(u64 next_event);
/** Stop timer event for current HART */
void (*timer_event_stop)(void);
/** Initialize timer device for current HART */
int (*warm_init)(void);
};
struct sbi_scratch;
/** Generic delay loop of desired granularity */
void sbi_timer_delay_loop(ulong units, u64 unit_freq,
void (*delay_fn)(void *), void *opaque);
/** Provide delay in terms of milliseconds */
static inline void sbi_timer_mdelay(ulong msecs)
{
sbi_timer_delay_loop(msecs, 1000, NULL, NULL);
}
/** Provide delay in terms of microseconds */
static inline void sbi_timer_udelay(ulong usecs)
{
sbi_timer_delay_loop(usecs, 1000000, NULL, NULL);
}
/**
* A blocking function that will wait until @p predicate returns true or
* @p timeout_ms milliseconds elapsed. @p arg will be passed as argument to
* @p predicate function.
*
* @param predicate Pointer to a function that returns true if certain
* condition is met. It shouldn't block the code execution.
* @param arg Argument to pass to @p predicate.
* @param timeout_ms Timeout value in milliseconds. The function will return
* false if @p timeout_ms time period elapsed but still @p predicate doesn't
* return true.
*
* @return true if @p predicate returns true within @p timeout_ms, false
* otherwise.
*/
bool sbi_timer_waitms_until(bool (*predicate)(void *), void *arg,
uint64_t timeout_ms);
/** Get timer value for current HART */
u64 sbi_timer_value(void);
/** Get virtualized timer value for current HART */
u64 sbi_timer_virt_value(void);
/** Get timer delta value for current HART */
u64 sbi_timer_get_delta(void);
/** Set timer delta value for current HART */
void sbi_timer_set_delta(ulong delta);
#if __riscv_xlen == 32
/** Set upper 32-bits of timer delta value for current HART */
void sbi_timer_set_delta_upper(ulong delta_upper);
#endif
/** Start timer event for current HART */
void sbi_timer_event_start(u64 next_event);
/** Process timer event for current HART */
void sbi_timer_process(void);
/** Get current timer device */
const struct sbi_timer_device *sbi_timer_get_device(void);
/** Register timer device */
void sbi_timer_set_device(const struct sbi_timer_device *dev);
/* Initialize timer */
int sbi_timer_init(struct sbi_scratch *scratch, bool cold_boot);
/* Exit timer */
void sbi_timer_exit(struct sbi_scratch *scratch);
#endif