57 lines
1.4 KiB
C
57 lines
1.4 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
|
|
*
|
|
* RISC-V privileged architecture defined generic timer driver
|
|
*
|
|
* This driver relies on RISC-V platform codes to provide the essential API
|
|
* riscv_get_time() which is supposed to return the timer counter as defined
|
|
* by the RISC-V privileged architecture spec.
|
|
*
|
|
* This driver can be used in both M-mode and S-mode U-Boot.
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <dm.h>
|
|
#include <errno.h>
|
|
#include <timer.h>
|
|
#include <asm/io.h>
|
|
|
|
/**
|
|
* riscv_get_time() - get the timer counter
|
|
*
|
|
* Platform codes should provide this API in order to make this driver function.
|
|
*
|
|
* @time: the 64-bit timer count as defined by the RISC-V privileged
|
|
* architecture spec.
|
|
* @return: 0 on success, -ve on error.
|
|
*/
|
|
extern int riscv_get_time(u64 *time);
|
|
|
|
static int riscv_timer_get_count(struct udevice *dev, u64 *count)
|
|
{
|
|
return riscv_get_time(count);
|
|
}
|
|
|
|
static int riscv_timer_probe(struct udevice *dev)
|
|
{
|
|
struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
|
|
|
|
/* clock frequency was passed from the cpu driver as driver data */
|
|
uc_priv->clock_rate = dev->driver_data;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct timer_ops riscv_timer_ops = {
|
|
.get_count = riscv_timer_get_count,
|
|
};
|
|
|
|
U_BOOT_DRIVER(riscv_timer) = {
|
|
.name = "riscv_timer",
|
|
.id = UCLASS_TIMER,
|
|
.probe = riscv_timer_probe,
|
|
.ops = &riscv_timer_ops,
|
|
.flags = DM_FLAG_PRE_RELOC,
|
|
};
|