u-boot/drivers/timer/sifive_clint_timer.c
Bin Meng 5764acb261 riscv: timer: Update the sifive clint timer driver to support aclint
This RISC-V ACLINT specification [1] defines a set of memory mapped
devices which provide inter-processor interrupts (IPI) and timer
functionalities for each HART on a multi-HART RISC-V platform.

The RISC-V ACLINT specification is defined to be backward compatible
with the SiFive CLINT specification, however the device tree binding
is a new one. This change updates the sifive clint timer driver to
support ACLINT mtimer device, using a per-driver data field to hold
the mtimer offset to the base address encoded in the mtimer node.

[1] https://github.com/riscv/riscv-aclint/blob/main/riscv-aclint.adoc

Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Rick Chen <rick@andestech.com>
2023-07-12 13:21:40 +08:00

75 lines
1.8 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2020, Sean Anderson <seanga2@gmail.com>
* Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
*/
#include <common.h>
#include <clk.h>
#include <dm.h>
#include <timer.h>
#include <asm/io.h>
#include <dm/device-internal.h>
#include <linux/err.h>
#define CLINT_MTIME_OFFSET 0xbff8
#define ACLINT_MTIME_OFFSET 0
/* mtime register */
#define MTIME_REG(base, offset) ((ulong)(base) + (offset))
static u64 notrace sifive_clint_get_count(struct udevice *dev)
{
return readq((void __iomem *)MTIME_REG(dev_get_priv(dev),
dev_get_driver_data(dev)));
}
#if CONFIG_IS_ENABLED(RISCV_MMODE) && IS_ENABLED(CONFIG_TIMER_EARLY)
/**
* timer_early_get_rate() - Get the timer rate before driver model
*/
unsigned long notrace timer_early_get_rate(void)
{
return RISCV_MMODE_TIMER_FREQ;
}
/**
* timer_early_get_count() - Get the timer count before driver model
*
*/
u64 notrace timer_early_get_count(void)
{
return readq((void __iomem *)MTIME_REG(RISCV_MMODE_TIMERBASE,
RISCV_MMODE_TIMEROFF));
}
#endif
static const struct timer_ops sifive_clint_ops = {
.get_count = sifive_clint_get_count,
};
static int sifive_clint_probe(struct udevice *dev)
{
dev_set_priv(dev, dev_read_addr_ptr(dev));
if (!dev_get_priv(dev))
return -EINVAL;
return timer_timebase_fallback(dev);
}
static const struct udevice_id sifive_clint_ids[] = {
{ .compatible = "riscv,clint0", .data = CLINT_MTIME_OFFSET },
{ .compatible = "sifive,clint0", .data = CLINT_MTIME_OFFSET },
{ .compatible = "riscv,aclint-mtimer", .data = ACLINT_MTIME_OFFSET },
{ }
};
U_BOOT_DRIVER(sifive_clint) = {
.name = "sifive_clint",
.id = UCLASS_TIMER,
.of_match = sifive_clint_ids,
.probe = sifive_clint_probe,
.ops = &sifive_clint_ops,
.flags = DM_FLAG_PRE_RELOC,
};