OpenCloudOS-Kernel/drivers/clk/bcm/clk-bcm63268-timer.c

217 lines
5.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* BCM63268 Timer Clock and Reset Controller Driver
*
* Copyright (C) 2023 Álvaro Fernández Rojas <noltari@gmail.com>
*/
#include <linux/clk-provider.h>
#include <linux/container_of.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/reset-controller.h>
#include <linux/spinlock.h>
#include <dt-bindings/clock/bcm63268-clock.h>
#define BCM63268_TIMER_RESET_SLEEP_MIN_US 10000
#define BCM63268_TIMER_RESET_SLEEP_MAX_US 20000
struct bcm63268_tclkrst_hw {
void __iomem *regs;
spinlock_t lock;
struct reset_controller_dev rcdev;
struct clk_hw_onecell_data data;
};
struct bcm63268_tclk_table_entry {
const char * const name;
u8 bit;
};
static const struct bcm63268_tclk_table_entry bcm63268_timer_clocks[] = {
{
.name = "ephy1",
.bit = BCM63268_TCLK_EPHY1,
}, {
.name = "ephy2",
.bit = BCM63268_TCLK_EPHY2,
}, {
.name = "ephy3",
.bit = BCM63268_TCLK_EPHY3,
}, {
.name = "gphy1",
.bit = BCM63268_TCLK_GPHY1,
}, {
.name = "dsl",
.bit = BCM63268_TCLK_DSL,
}, {
.name = "wakeon_ephy",
.bit = BCM63268_TCLK_WAKEON_EPHY,
}, {
.name = "wakeon_dsl",
.bit = BCM63268_TCLK_WAKEON_DSL,
}, {
.name = "fap1_pll",
.bit = BCM63268_TCLK_FAP1,
}, {
.name = "fap2_pll",
.bit = BCM63268_TCLK_FAP2,
}, {
.name = "uto_50",
.bit = BCM63268_TCLK_UTO_50,
}, {
.name = "uto_extin",
.bit = BCM63268_TCLK_UTO_EXTIN,
}, {
.name = "usb_ref",
.bit = BCM63268_TCLK_USB_REF,
}, {
/* sentinel */
}
};
static inline struct bcm63268_tclkrst_hw *
to_bcm63268_timer_reset(struct reset_controller_dev *rcdev)
{
return container_of(rcdev, struct bcm63268_tclkrst_hw, rcdev);
}
static int bcm63268_timer_reset_update(struct reset_controller_dev *rcdev,
unsigned long id, bool assert)
{
struct bcm63268_tclkrst_hw *reset = to_bcm63268_timer_reset(rcdev);
unsigned long flags;
uint32_t val;
spin_lock_irqsave(&reset->lock, flags);
val = __raw_readl(reset->regs);
if (assert)
val &= ~BIT(id);
else
val |= BIT(id);
__raw_writel(val, reset->regs);
spin_unlock_irqrestore(&reset->lock, flags);
return 0;
}
static int bcm63268_timer_reset_assert(struct reset_controller_dev *rcdev,
unsigned long id)
{
return bcm63268_timer_reset_update(rcdev, id, true);
}
static int bcm63268_timer_reset_deassert(struct reset_controller_dev *rcdev,
unsigned long id)
{
return bcm63268_timer_reset_update(rcdev, id, false);
}
static int bcm63268_timer_reset_reset(struct reset_controller_dev *rcdev,
unsigned long id)
{
bcm63268_timer_reset_update(rcdev, id, true);
usleep_range(BCM63268_TIMER_RESET_SLEEP_MIN_US,
BCM63268_TIMER_RESET_SLEEP_MAX_US);
bcm63268_timer_reset_update(rcdev, id, false);
/*
* Ensure component is taken out reset state by sleeping also after
* deasserting the reset. Otherwise, the component may not be ready
* for operation.
*/
usleep_range(BCM63268_TIMER_RESET_SLEEP_MIN_US,
BCM63268_TIMER_RESET_SLEEP_MAX_US);
return 0;
}
static int bcm63268_timer_reset_status(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct bcm63268_tclkrst_hw *reset = to_bcm63268_timer_reset(rcdev);
return !(__raw_readl(reset->regs) & BIT(id));
}
static const struct reset_control_ops bcm63268_timer_reset_ops = {
.assert = bcm63268_timer_reset_assert,
.deassert = bcm63268_timer_reset_deassert,
.reset = bcm63268_timer_reset_reset,
.status = bcm63268_timer_reset_status,
};
static int bcm63268_tclk_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
const struct bcm63268_tclk_table_entry *entry;
struct bcm63268_tclkrst_hw *hw;
struct clk_hw *clk;
u8 maxbit = 0;
int i, ret;
for (entry = bcm63268_timer_clocks; entry->name; entry++)
maxbit = max(maxbit, entry->bit);
maxbit++;
hw = devm_kzalloc(&pdev->dev, struct_size(hw, data.hws, maxbit),
GFP_KERNEL);
if (!hw)
return -ENOMEM;
platform_set_drvdata(pdev, hw);
spin_lock_init(&hw->lock);
hw->data.num = maxbit;
for (i = 0; i < maxbit; i++)
hw->data.hws[i] = ERR_PTR(-ENODEV);
hw->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(hw->regs))
return PTR_ERR(hw->regs);
for (entry = bcm63268_timer_clocks; entry->name; entry++) {
clk = devm_clk_hw_register_gate(dev, entry->name, NULL, 0,
hw->regs, entry->bit,
CLK_GATE_BIG_ENDIAN,
&hw->lock);
if (IS_ERR(clk))
return PTR_ERR(clk);
hw->data.hws[entry->bit] = clk;
}
ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
&hw->data);
if (ret)
return ret;
hw->rcdev.of_node = dev->of_node;
hw->rcdev.ops = &bcm63268_timer_reset_ops;
ret = devm_reset_controller_register(dev, &hw->rcdev);
if (ret)
dev_err(dev, "Failed to register reset controller\n");
return 0;
}
static const struct of_device_id bcm63268_tclk_dt_ids[] = {
{ .compatible = "brcm,bcm63268-timer-clocks" },
{ /* sentinel */ }
};
static struct platform_driver bcm63268_tclk = {
.probe = bcm63268_tclk_probe,
.driver = {
.name = "bcm63268-timer-clock",
.of_match_table = bcm63268_tclk_dt_ids,
},
};
builtin_platform_driver(bcm63268_tclk);