OpenCloudOS-Kernel/drivers/clk/ingenic/tcu.c

497 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* JZ47xx SoCs TCU clocks driver
* Copyright (C) 2019 Paul Cercueil <paul@crapouillou.net>
*/
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/clockchips.h>
#include <linux/mfd/ingenic-tcu.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/syscore_ops.h>
#include <dt-bindings/clock/ingenic,tcu.h>
/* 8 channels max + watchdog + OST */
#define TCU_CLK_COUNT 10
#undef pr_fmt
#define pr_fmt(fmt) "ingenic-tcu-clk: " fmt
enum tcu_clk_parent {
TCU_PARENT_PCLK,
TCU_PARENT_RTC,
TCU_PARENT_EXT,
};
struct ingenic_soc_info {
unsigned int num_channels;
bool has_ost;
bool has_tcu_clk;
bool allow_missing_tcu_clk;
};
struct ingenic_tcu_clk_info {
struct clk_init_data init_data;
u8 gate_bit;
u8 tcsr_reg;
};
struct ingenic_tcu_clk {
struct clk_hw hw;
unsigned int idx;
struct ingenic_tcu *tcu;
const struct ingenic_tcu_clk_info *info;
};
struct ingenic_tcu {
const struct ingenic_soc_info *soc_info;
struct regmap *map;
struct clk *clk;
struct clk_hw_onecell_data *clocks;
};
static struct ingenic_tcu *ingenic_tcu;
static inline struct ingenic_tcu_clk *to_tcu_clk(struct clk_hw *hw)
{
return container_of(hw, struct ingenic_tcu_clk, hw);
}
static int ingenic_tcu_enable(struct clk_hw *hw)
{
struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
const struct ingenic_tcu_clk_info *info = tcu_clk->info;
struct ingenic_tcu *tcu = tcu_clk->tcu;
regmap_write(tcu->map, TCU_REG_TSCR, BIT(info->gate_bit));
return 0;
}
static void ingenic_tcu_disable(struct clk_hw *hw)
{
struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
const struct ingenic_tcu_clk_info *info = tcu_clk->info;
struct ingenic_tcu *tcu = tcu_clk->tcu;
regmap_write(tcu->map, TCU_REG_TSSR, BIT(info->gate_bit));
}
static int ingenic_tcu_is_enabled(struct clk_hw *hw)
{
struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
const struct ingenic_tcu_clk_info *info = tcu_clk->info;
unsigned int value;
regmap_read(tcu_clk->tcu->map, TCU_REG_TSR, &value);
return !(value & BIT(info->gate_bit));
}
static bool ingenic_tcu_enable_regs(struct clk_hw *hw)
{
struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
const struct ingenic_tcu_clk_info *info = tcu_clk->info;
struct ingenic_tcu *tcu = tcu_clk->tcu;
bool enabled = false;
/*
* According to the programming manual, a timer channel's registers can
* only be accessed when the channel's stop bit is clear.
*/
enabled = !!ingenic_tcu_is_enabled(hw);
regmap_write(tcu->map, TCU_REG_TSCR, BIT(info->gate_bit));
return enabled;
}
static void ingenic_tcu_disable_regs(struct clk_hw *hw)
{
struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
const struct ingenic_tcu_clk_info *info = tcu_clk->info;
struct ingenic_tcu *tcu = tcu_clk->tcu;
regmap_write(tcu->map, TCU_REG_TSSR, BIT(info->gate_bit));
}
static u8 ingenic_tcu_get_parent(struct clk_hw *hw)
{
struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
const struct ingenic_tcu_clk_info *info = tcu_clk->info;
unsigned int val = 0;
int ret;
ret = regmap_read(tcu_clk->tcu->map, info->tcsr_reg, &val);
WARN_ONCE(ret < 0, "Unable to read TCSR %d", tcu_clk->idx);
return ffs(val & TCU_TCSR_PARENT_CLOCK_MASK) - 1;
}
static int ingenic_tcu_set_parent(struct clk_hw *hw, u8 idx)
{
struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
const struct ingenic_tcu_clk_info *info = tcu_clk->info;
bool was_enabled;
int ret;
was_enabled = ingenic_tcu_enable_regs(hw);
ret = regmap_update_bits(tcu_clk->tcu->map, info->tcsr_reg,
TCU_TCSR_PARENT_CLOCK_MASK, BIT(idx));
WARN_ONCE(ret < 0, "Unable to update TCSR %d", tcu_clk->idx);
if (!was_enabled)
ingenic_tcu_disable_regs(hw);
return 0;
}
static unsigned long ingenic_tcu_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
const struct ingenic_tcu_clk_info *info = tcu_clk->info;
unsigned int prescale;
int ret;
ret = regmap_read(tcu_clk->tcu->map, info->tcsr_reg, &prescale);
WARN_ONCE(ret < 0, "Unable to read TCSR %d", tcu_clk->idx);
prescale = (prescale & TCU_TCSR_PRESCALE_MASK) >> TCU_TCSR_PRESCALE_LSB;
return parent_rate >> (prescale * 2);
}
static u8 ingenic_tcu_get_prescale(unsigned long rate, unsigned long req_rate)
{
u8 prescale;
for (prescale = 0; prescale < 5; prescale++)
if ((rate >> (prescale * 2)) <= req_rate)
return prescale;
return 5; /* /1024 divider */
}
static int ingenic_tcu_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
unsigned long rate = req->best_parent_rate;
u8 prescale;
if (req->rate > rate) {
req->rate = rate;
return 0;
}
prescale = ingenic_tcu_get_prescale(rate, req->rate);
req->rate = rate >> (prescale * 2);
return 0;
}
static int ingenic_tcu_set_rate(struct clk_hw *hw, unsigned long req_rate,
unsigned long parent_rate)
{
struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw);
const struct ingenic_tcu_clk_info *info = tcu_clk->info;
u8 prescale = ingenic_tcu_get_prescale(parent_rate, req_rate);
bool was_enabled;
int ret;
was_enabled = ingenic_tcu_enable_regs(hw);
ret = regmap_update_bits(tcu_clk->tcu->map, info->tcsr_reg,
TCU_TCSR_PRESCALE_MASK,
prescale << TCU_TCSR_PRESCALE_LSB);
WARN_ONCE(ret < 0, "Unable to update TCSR %d", tcu_clk->idx);
if (!was_enabled)
ingenic_tcu_disable_regs(hw);
return 0;
}
static const struct clk_ops ingenic_tcu_clk_ops = {
.get_parent = ingenic_tcu_get_parent,
.set_parent = ingenic_tcu_set_parent,
.recalc_rate = ingenic_tcu_recalc_rate,
.determine_rate = ingenic_tcu_determine_rate,
.set_rate = ingenic_tcu_set_rate,
.enable = ingenic_tcu_enable,
.disable = ingenic_tcu_disable,
.is_enabled = ingenic_tcu_is_enabled,
};
static const char * const ingenic_tcu_timer_parents[] = {
[TCU_PARENT_PCLK] = "pclk",
[TCU_PARENT_RTC] = "rtc",
[TCU_PARENT_EXT] = "ext",
};
#define DEF_TIMER(_name, _gate_bit, _tcsr) \
{ \
.init_data = { \
.name = _name, \
.parent_names = ingenic_tcu_timer_parents, \
.num_parents = ARRAY_SIZE(ingenic_tcu_timer_parents),\
.ops = &ingenic_tcu_clk_ops, \
.flags = CLK_SET_RATE_UNGATE, \
}, \
.gate_bit = _gate_bit, \
.tcsr_reg = _tcsr, \
}
static const struct ingenic_tcu_clk_info ingenic_tcu_clk_info[] = {
[TCU_CLK_TIMER0] = DEF_TIMER("timer0", 0, TCU_REG_TCSRc(0)),
[TCU_CLK_TIMER1] = DEF_TIMER("timer1", 1, TCU_REG_TCSRc(1)),
[TCU_CLK_TIMER2] = DEF_TIMER("timer2", 2, TCU_REG_TCSRc(2)),
[TCU_CLK_TIMER3] = DEF_TIMER("timer3", 3, TCU_REG_TCSRc(3)),
[TCU_CLK_TIMER4] = DEF_TIMER("timer4", 4, TCU_REG_TCSRc(4)),
[TCU_CLK_TIMER5] = DEF_TIMER("timer5", 5, TCU_REG_TCSRc(5)),
[TCU_CLK_TIMER6] = DEF_TIMER("timer6", 6, TCU_REG_TCSRc(6)),
[TCU_CLK_TIMER7] = DEF_TIMER("timer7", 7, TCU_REG_TCSRc(7)),
};
static const struct ingenic_tcu_clk_info ingenic_tcu_watchdog_clk_info =
DEF_TIMER("wdt", 16, TCU_REG_WDT_TCSR);
static const struct ingenic_tcu_clk_info ingenic_tcu_ost_clk_info =
DEF_TIMER("ost", 15, TCU_REG_OST_TCSR);
#undef DEF_TIMER
static int __init ingenic_tcu_register_clock(struct ingenic_tcu *tcu,
unsigned int idx, enum tcu_clk_parent parent,
const struct ingenic_tcu_clk_info *info,
struct clk_hw_onecell_data *clocks)
{
struct ingenic_tcu_clk *tcu_clk;
int err;
tcu_clk = kzalloc(sizeof(*tcu_clk), GFP_KERNEL);
if (!tcu_clk)
return -ENOMEM;
tcu_clk->hw.init = &info->init_data;
tcu_clk->idx = idx;
tcu_clk->info = info;
tcu_clk->tcu = tcu;
/* Reset channel and clock divider, set default parent */
ingenic_tcu_enable_regs(&tcu_clk->hw);
regmap_update_bits(tcu->map, info->tcsr_reg, 0xffff, BIT(parent));
ingenic_tcu_disable_regs(&tcu_clk->hw);
err = clk_hw_register(NULL, &tcu_clk->hw);
if (err) {
kfree(tcu_clk);
return err;
}
clocks->hws[idx] = &tcu_clk->hw;
return 0;
}
static const struct ingenic_soc_info jz4740_soc_info = {
.num_channels = 8,
.has_ost = false,
.has_tcu_clk = true,
};
static const struct ingenic_soc_info jz4725b_soc_info = {
.num_channels = 6,
.has_ost = true,
.has_tcu_clk = true,
};
static const struct ingenic_soc_info jz4770_soc_info = {
.num_channels = 8,
.has_ost = true,
.has_tcu_clk = false,
};
static const struct ingenic_soc_info x1000_soc_info = {
.num_channels = 8,
.has_ost = false, /* X1000 has OST, but it not belong TCU */
.has_tcu_clk = true,
.allow_missing_tcu_clk = true,
};
static const struct of_device_id __maybe_unused ingenic_tcu_of_match[] __initconst = {
{ .compatible = "ingenic,jz4740-tcu", .data = &jz4740_soc_info, },
{ .compatible = "ingenic,jz4725b-tcu", .data = &jz4725b_soc_info, },
{ .compatible = "ingenic,jz4760-tcu", .data = &jz4770_soc_info, },
{ .compatible = "ingenic,jz4770-tcu", .data = &jz4770_soc_info, },
{ .compatible = "ingenic,x1000-tcu", .data = &x1000_soc_info, },
{ /* sentinel */ }
};
static int __init ingenic_tcu_probe(struct device_node *np)
{
const struct of_device_id *id = of_match_node(ingenic_tcu_of_match, np);
struct ingenic_tcu *tcu;
struct regmap *map;
unsigned int i;
int ret;
map = device_node_to_regmap(np);
if (IS_ERR(map))
return PTR_ERR(map);
tcu = kzalloc(sizeof(*tcu), GFP_KERNEL);
if (!tcu)
return -ENOMEM;
tcu->map = map;
tcu->soc_info = id->data;
if (tcu->soc_info->has_tcu_clk) {
tcu->clk = of_clk_get_by_name(np, "tcu");
if (IS_ERR(tcu->clk)) {
ret = PTR_ERR(tcu->clk);
/*
* Old device trees for some SoCs did not include the
* TCU clock because this driver (incorrectly) didn't
* use it. In this case we complain loudly and attempt
* to continue without the clock, which might work if
* booting with workarounds like "clk_ignore_unused".
*/
if (tcu->soc_info->allow_missing_tcu_clk && ret == -EINVAL) {
pr_warn("TCU clock missing from device tree, please update your device tree\n");
tcu->clk = NULL;
} else {
pr_crit("Cannot get TCU clock from device tree\n");
goto err_free_tcu;
}
} else {
ret = clk_prepare_enable(tcu->clk);
if (ret) {
pr_crit("Unable to enable TCU clock\n");
goto err_put_clk;
}
}
}
tcu->clocks = kzalloc(struct_size(tcu->clocks, hws, TCU_CLK_COUNT),
GFP_KERNEL);
if (!tcu->clocks) {
ret = -ENOMEM;
goto err_clk_disable;
}
tcu->clocks->num = TCU_CLK_COUNT;
for (i = 0; i < tcu->soc_info->num_channels; i++) {
ret = ingenic_tcu_register_clock(tcu, i, TCU_PARENT_EXT,
&ingenic_tcu_clk_info[i],
tcu->clocks);
if (ret) {
pr_crit("cannot register clock %d\n", i);
goto err_unregister_timer_clocks;
}
}
/*
* We set EXT as the default parent clock for all the TCU clocks
* except for the watchdog one, where we set the RTC clock as the
* parent. Since the EXT and PCLK are much faster than the RTC clock,
* the watchdog would kick after a maximum time of 5s, and we might
* want a slower kicking time.
*/
ret = ingenic_tcu_register_clock(tcu, TCU_CLK_WDT, TCU_PARENT_RTC,
&ingenic_tcu_watchdog_clk_info,
tcu->clocks);
if (ret) {
pr_crit("cannot register watchdog clock\n");
goto err_unregister_timer_clocks;
}
if (tcu->soc_info->has_ost) {
ret = ingenic_tcu_register_clock(tcu, TCU_CLK_OST,
TCU_PARENT_EXT,
&ingenic_tcu_ost_clk_info,
tcu->clocks);
if (ret) {
pr_crit("cannot register ost clock\n");
goto err_unregister_watchdog_clock;
}
}
ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, tcu->clocks);
if (ret) {
pr_crit("cannot add OF clock provider\n");
goto err_unregister_ost_clock;
}
ingenic_tcu = tcu;
return 0;
err_unregister_ost_clock:
if (tcu->soc_info->has_ost)
clk_hw_unregister(tcu->clocks->hws[i + 1]);
err_unregister_watchdog_clock:
clk_hw_unregister(tcu->clocks->hws[i]);
err_unregister_timer_clocks:
for (i = 0; i < tcu->clocks->num; i++)
if (tcu->clocks->hws[i])
clk_hw_unregister(tcu->clocks->hws[i]);
kfree(tcu->clocks);
err_clk_disable:
if (tcu->clk)
clk_disable_unprepare(tcu->clk);
err_put_clk:
if (tcu->clk)
clk_put(tcu->clk);
err_free_tcu:
kfree(tcu);
return ret;
}
static int __maybe_unused tcu_pm_suspend(void)
{
struct ingenic_tcu *tcu = ingenic_tcu;
if (tcu->clk)
clk_disable(tcu->clk);
return 0;
}
static void __maybe_unused tcu_pm_resume(void)
{
struct ingenic_tcu *tcu = ingenic_tcu;
if (tcu->clk)
clk_enable(tcu->clk);
}
static struct syscore_ops __maybe_unused tcu_pm_ops = {
.suspend = tcu_pm_suspend,
.resume = tcu_pm_resume,
};
static void __init ingenic_tcu_init(struct device_node *np)
{
int ret = ingenic_tcu_probe(np);
if (ret)
pr_crit("Failed to initialize TCU clocks: %d\n", ret);
if (IS_ENABLED(CONFIG_PM_SLEEP))
register_syscore_ops(&tcu_pm_ops);
}
CLK_OF_DECLARE_DRIVER(jz4740_cgu, "ingenic,jz4740-tcu", ingenic_tcu_init);
CLK_OF_DECLARE_DRIVER(jz4725b_cgu, "ingenic,jz4725b-tcu", ingenic_tcu_init);
CLK_OF_DECLARE_DRIVER(jz4760_cgu, "ingenic,jz4760-tcu", ingenic_tcu_init);
CLK_OF_DECLARE_DRIVER(jz4770_cgu, "ingenic,jz4770-tcu", ingenic_tcu_init);
CLK_OF_DECLARE_DRIVER(x1000_cgu, "ingenic,x1000-tcu", ingenic_tcu_init);