u-boot-brain/drivers/timer/dw-apb-timer.c

104 lines
2.2 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Designware APB Timer driver
*
* Copyright (C) 2018 Marek Vasut <marex@denx.de>
*/
#include <common.h>
#include <dm.h>
#include <clk.h>
#include <malloc.h>
#include <reset.h>
#include <timer.h>
#include <dm/device_compat.h>
#include <asm/io.h>
#include <asm/arch/timer.h>
#define DW_APB_LOAD_VAL 0x0
#define DW_APB_CURR_VAL 0x4
#define DW_APB_CTRL 0x8
struct dw_apb_timer_priv {
fdt_addr_t regs;
struct reset_ctl_bulk resets;
};
static u64 dw_apb_timer_get_count(struct udevice *dev)
{
struct dw_apb_timer_priv *priv = dev_get_priv(dev);
/*
* The DW APB counter counts down, but this function
* requires the count to be incrementing. Invert the
* result.
*/
return timer_conv_64(~readl(priv->regs + DW_APB_CURR_VAL));
}
static int dw_apb_timer_probe(struct udevice *dev)
{
struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
struct dw_apb_timer_priv *priv = dev_get_priv(dev);
struct clk clk;
int ret;
ret = reset_get_bulk(dev, &priv->resets);
if (ret)
dev_warn(dev, "Can't get reset: %d\n", ret);
else
reset_deassert_bulk(&priv->resets);
ret = clk_get_by_index(dev, 0, &clk);
if (ret)
return ret;
uc_priv->clock_rate = clk_get_rate(&clk);
clk_free(&clk);
/* init timer */
writel(0xffffffff, priv->regs + DW_APB_LOAD_VAL);
writel(0xffffffff, priv->regs + DW_APB_CURR_VAL);
setbits_le32(priv->regs + DW_APB_CTRL, 0x3);
return 0;
}
static int dw_apb_timer_of_to_plat(struct udevice *dev)
{
struct dw_apb_timer_priv *priv = dev_get_priv(dev);
priv->regs = dev_read_addr(dev);
return 0;
}
static int dw_apb_timer_remove(struct udevice *dev)
{
struct dw_apb_timer_priv *priv = dev_get_priv(dev);
return reset_release_bulk(&priv->resets);
}
static const struct timer_ops dw_apb_timer_ops = {
.get_count = dw_apb_timer_get_count,
};
static const struct udevice_id dw_apb_timer_ids[] = {
{ .compatible = "snps,dw-apb-timer" },
{}
};
U_BOOT_DRIVER(dw_apb_timer) = {
.name = "dw_apb_timer",
.id = UCLASS_TIMER,
.ops = &dw_apb_timer_ops,
.probe = dw_apb_timer_probe,
.of_match = dw_apb_timer_ids,
.of_to_plat = dw_apb_timer_of_to_plat,
.remove = dw_apb_timer_remove,
.priv_auto = sizeof(struct dw_apb_timer_priv),
};