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linux/drivers/clocksource/sh_mtu2.c
Ulf Hansson fc51989062 PM: domains: Rename pm_genpd_syscore_poweroff|poweron() 
To better describe what the pm_genpd_syscore_poweroff|poweron() functions
actually do, let's rename them to dev_pm_genpd_suspend|resume() and update
the rather few callers of them accordingly (a couple of clocksource
drivers).

Moreover, let's take the opportunity to add some documentation of these
exported functions, as that is currently missing.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-10 20:42:01 +01:00

534 lines
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// SPDX-License-Identifier: GPL-2.0
/*
* SuperH Timer Support - MTU2
*
* Copyright (C) 2009 Magnus Damm
*/
#include <linux/clk.h>
#include <linux/clockchips.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
#include <linux/sh_timer.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#ifdef CONFIG_SUPERH
#include <asm/platform_early.h>
#endif
struct sh_mtu2_device;
struct sh_mtu2_channel {
struct sh_mtu2_device *mtu;
unsigned int index;
void __iomem *base;
struct clock_event_device ced;
};
struct sh_mtu2_device {
struct platform_device *pdev;
void __iomem *mapbase;
struct clk *clk;
raw_spinlock_t lock; /* Protect the shared registers */
struct sh_mtu2_channel *channels;
unsigned int num_channels;
bool has_clockevent;
};
#define TSTR -1 /* shared register */
#define TCR 0 /* channel register */
#define TMDR 1 /* channel register */
#define TIOR 2 /* channel register */
#define TIER 3 /* channel register */
#define TSR 4 /* channel register */
#define TCNT 5 /* channel register */
#define TGR 6 /* channel register */
#define TCR_CCLR_NONE (0 << 5)
#define TCR_CCLR_TGRA (1 << 5)
#define TCR_CCLR_TGRB (2 << 5)
#define TCR_CCLR_SYNC (3 << 5)
#define TCR_CCLR_TGRC (5 << 5)
#define TCR_CCLR_TGRD (6 << 5)
#define TCR_CCLR_MASK (7 << 5)
#define TCR_CKEG_RISING (0 << 3)
#define TCR_CKEG_FALLING (1 << 3)
#define TCR_CKEG_BOTH (2 << 3)
#define TCR_CKEG_MASK (3 << 3)
/* Values 4 to 7 are channel-dependent */
#define TCR_TPSC_P1 (0 << 0)
#define TCR_TPSC_P4 (1 << 0)
#define TCR_TPSC_P16 (2 << 0)
#define TCR_TPSC_P64 (3 << 0)
#define TCR_TPSC_CH0_TCLKA (4 << 0)
#define TCR_TPSC_CH0_TCLKB (5 << 0)
#define TCR_TPSC_CH0_TCLKC (6 << 0)
#define TCR_TPSC_CH0_TCLKD (7 << 0)
#define TCR_TPSC_CH1_TCLKA (4 << 0)
#define TCR_TPSC_CH1_TCLKB (5 << 0)
#define TCR_TPSC_CH1_P256 (6 << 0)
#define TCR_TPSC_CH1_TCNT2 (7 << 0)
#define TCR_TPSC_CH2_TCLKA (4 << 0)
#define TCR_TPSC_CH2_TCLKB (5 << 0)
#define TCR_TPSC_CH2_TCLKC (6 << 0)
#define TCR_TPSC_CH2_P1024 (7 << 0)
#define TCR_TPSC_CH34_P256 (4 << 0)
#define TCR_TPSC_CH34_P1024 (5 << 0)
#define TCR_TPSC_CH34_TCLKA (6 << 0)
#define TCR_TPSC_CH34_TCLKB (7 << 0)
#define TCR_TPSC_MASK (7 << 0)
#define TMDR_BFE (1 << 6)
#define TMDR_BFB (1 << 5)
#define TMDR_BFA (1 << 4)
#define TMDR_MD_NORMAL (0 << 0)
#define TMDR_MD_PWM_1 (2 << 0)
#define TMDR_MD_PWM_2 (3 << 0)
#define TMDR_MD_PHASE_1 (4 << 0)
#define TMDR_MD_PHASE_2 (5 << 0)
#define TMDR_MD_PHASE_3 (6 << 0)
#define TMDR_MD_PHASE_4 (7 << 0)
#define TMDR_MD_PWM_SYNC (8 << 0)
#define TMDR_MD_PWM_COMP_CREST (13 << 0)
#define TMDR_MD_PWM_COMP_TROUGH (14 << 0)
#define TMDR_MD_PWM_COMP_BOTH (15 << 0)
#define TMDR_MD_MASK (15 << 0)
#define TIOC_IOCH(n) ((n) << 4)
#define TIOC_IOCL(n) ((n) << 0)
#define TIOR_OC_RETAIN (0 << 0)
#define TIOR_OC_0_CLEAR (1 << 0)
#define TIOR_OC_0_SET (2 << 0)
#define TIOR_OC_0_TOGGLE (3 << 0)
#define TIOR_OC_1_CLEAR (5 << 0)
#define TIOR_OC_1_SET (6 << 0)
#define TIOR_OC_1_TOGGLE (7 << 0)
#define TIOR_IC_RISING (8 << 0)
#define TIOR_IC_FALLING (9 << 0)
#define TIOR_IC_BOTH (10 << 0)
#define TIOR_IC_TCNT (12 << 0)
#define TIOR_MASK (15 << 0)
#define TIER_TTGE (1 << 7)
#define TIER_TTGE2 (1 << 6)
#define TIER_TCIEU (1 << 5)
#define TIER_TCIEV (1 << 4)
#define TIER_TGIED (1 << 3)
#define TIER_TGIEC (1 << 2)
#define TIER_TGIEB (1 << 1)
#define TIER_TGIEA (1 << 0)
#define TSR_TCFD (1 << 7)
#define TSR_TCFU (1 << 5)
#define TSR_TCFV (1 << 4)
#define TSR_TGFD (1 << 3)
#define TSR_TGFC (1 << 2)
#define TSR_TGFB (1 << 1)
#define TSR_TGFA (1 << 0)
static unsigned long mtu2_reg_offs[] = {
[TCR] = 0,
[TMDR] = 1,
[TIOR] = 2,
[TIER] = 4,
[TSR] = 5,
[TCNT] = 6,
[TGR] = 8,
};
static inline unsigned long sh_mtu2_read(struct sh_mtu2_channel *ch, int reg_nr)
{
unsigned long offs;
if (reg_nr == TSTR)
return ioread8(ch->mtu->mapbase + 0x280);
offs = mtu2_reg_offs[reg_nr];
if ((reg_nr == TCNT) || (reg_nr == TGR))
return ioread16(ch->base + offs);
else
return ioread8(ch->base + offs);
}
static inline void sh_mtu2_write(struct sh_mtu2_channel *ch, int reg_nr,
unsigned long value)
{
unsigned long offs;
if (reg_nr == TSTR)
return iowrite8(value, ch->mtu->mapbase + 0x280);
offs = mtu2_reg_offs[reg_nr];
if ((reg_nr == TCNT) || (reg_nr == TGR))
iowrite16(value, ch->base + offs);
else
iowrite8(value, ch->base + offs);
}
static void sh_mtu2_start_stop_ch(struct sh_mtu2_channel *ch, int start)
{
unsigned long flags, value;
/* start stop register shared by multiple timer channels */
raw_spin_lock_irqsave(&ch->mtu->lock, flags);
value = sh_mtu2_read(ch, TSTR);
if (start)
value |= 1 << ch->index;
else
value &= ~(1 << ch->index);
sh_mtu2_write(ch, TSTR, value);
raw_spin_unlock_irqrestore(&ch->mtu->lock, flags);
}
static int sh_mtu2_enable(struct sh_mtu2_channel *ch)
{
unsigned long periodic;
unsigned long rate;
int ret;
pm_runtime_get_sync(&ch->mtu->pdev->dev);
dev_pm_syscore_device(&ch->mtu->pdev->dev, true);
/* enable clock */
ret = clk_enable(ch->mtu->clk);
if (ret) {
dev_err(&ch->mtu->pdev->dev, "ch%u: cannot enable clock\n",
ch->index);
return ret;
}
/* make sure channel is disabled */
sh_mtu2_start_stop_ch(ch, 0);
rate = clk_get_rate(ch->mtu->clk) / 64;
periodic = (rate + HZ/2) / HZ;
/*
* "Periodic Counter Operation"
* Clear on TGRA compare match, divide clock by 64.
*/
sh_mtu2_write(ch, TCR, TCR_CCLR_TGRA | TCR_TPSC_P64);
sh_mtu2_write(ch, TIOR, TIOC_IOCH(TIOR_OC_0_CLEAR) |
TIOC_IOCL(TIOR_OC_0_CLEAR));
sh_mtu2_write(ch, TGR, periodic);
sh_mtu2_write(ch, TCNT, 0);
sh_mtu2_write(ch, TMDR, TMDR_MD_NORMAL);
sh_mtu2_write(ch, TIER, TIER_TGIEA);
/* enable channel */
sh_mtu2_start_stop_ch(ch, 1);
return 0;
}
static void sh_mtu2_disable(struct sh_mtu2_channel *ch)
{
/* disable channel */
sh_mtu2_start_stop_ch(ch, 0);
/* stop clock */
clk_disable(ch->mtu->clk);
dev_pm_syscore_device(&ch->mtu->pdev->dev, false);
pm_runtime_put(&ch->mtu->pdev->dev);
}
static irqreturn_t sh_mtu2_interrupt(int irq, void *dev_id)
{
struct sh_mtu2_channel *ch = dev_id;
/* acknowledge interrupt */
sh_mtu2_read(ch, TSR);
sh_mtu2_write(ch, TSR, ~TSR_TGFA);
/* notify clockevent layer */
ch->ced.event_handler(&ch->ced);
return IRQ_HANDLED;
}
static struct sh_mtu2_channel *ced_to_sh_mtu2(struct clock_event_device *ced)
{
return container_of(ced, struct sh_mtu2_channel, ced);
}
static int sh_mtu2_clock_event_shutdown(struct clock_event_device *ced)
{
struct sh_mtu2_channel *ch = ced_to_sh_mtu2(ced);
if (clockevent_state_periodic(ced))
sh_mtu2_disable(ch);
return 0;
}
static int sh_mtu2_clock_event_set_periodic(struct clock_event_device *ced)
{
struct sh_mtu2_channel *ch = ced_to_sh_mtu2(ced);
if (clockevent_state_periodic(ced))
sh_mtu2_disable(ch);
dev_info(&ch->mtu->pdev->dev, "ch%u: used for periodic clock events\n",
ch->index);
sh_mtu2_enable(ch);
return 0;
}
static void sh_mtu2_clock_event_suspend(struct clock_event_device *ced)
{
dev_pm_genpd_suspend(&ced_to_sh_mtu2(ced)->mtu->pdev->dev);
}
static void sh_mtu2_clock_event_resume(struct clock_event_device *ced)
{
dev_pm_genpd_resume(&ced_to_sh_mtu2(ced)->mtu->pdev->dev);
}
static void sh_mtu2_register_clockevent(struct sh_mtu2_channel *ch,
const char *name)
{
struct clock_event_device *ced = &ch->ced;
ced->name = name;
ced->features = CLOCK_EVT_FEAT_PERIODIC;
ced->rating = 200;
ced->cpumask = cpu_possible_mask;
ced->set_state_shutdown = sh_mtu2_clock_event_shutdown;
ced->set_state_periodic = sh_mtu2_clock_event_set_periodic;
ced->suspend = sh_mtu2_clock_event_suspend;
ced->resume = sh_mtu2_clock_event_resume;
dev_info(&ch->mtu->pdev->dev, "ch%u: used for clock events\n",
ch->index);
clockevents_register_device(ced);
}
static int sh_mtu2_register(struct sh_mtu2_channel *ch, const char *name)
{
ch->mtu->has_clockevent = true;
sh_mtu2_register_clockevent(ch, name);
return 0;
}
static const unsigned int sh_mtu2_channel_offsets[] = {
0x300, 0x380, 0x000,
};
static int sh_mtu2_setup_channel(struct sh_mtu2_channel *ch, unsigned int index,
struct sh_mtu2_device *mtu)
{
char name[6];
int irq;
int ret;
ch->mtu = mtu;
sprintf(name, "tgi%ua", index);
irq = platform_get_irq_byname(mtu->pdev, name);
if (irq < 0) {
/* Skip channels with no declared interrupt. */
return 0;
}
ret = request_irq(irq, sh_mtu2_interrupt,
IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
dev_name(&ch->mtu->pdev->dev), ch);
if (ret) {
dev_err(&ch->mtu->pdev->dev, "ch%u: failed to request irq %d\n",
index, irq);
return ret;
}
ch->base = mtu->mapbase + sh_mtu2_channel_offsets[index];
ch->index = index;
return sh_mtu2_register(ch, dev_name(&mtu->pdev->dev));
}
static int sh_mtu2_map_memory(struct sh_mtu2_device *mtu)
{
struct resource *res;
res = platform_get_resource(mtu->pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(&mtu->pdev->dev, "failed to get I/O memory\n");
return -ENXIO;
}
mtu->mapbase = ioremap(res->start, resource_size(res));
if (mtu->mapbase == NULL)
return -ENXIO;
return 0;
}
static int sh_mtu2_setup(struct sh_mtu2_device *mtu,
struct platform_device *pdev)
{
unsigned int i;
int ret;
mtu->pdev = pdev;
raw_spin_lock_init(&mtu->lock);
/* Get hold of clock. */
mtu->clk = clk_get(&mtu->pdev->dev, "fck");
if (IS_ERR(mtu->clk)) {
dev_err(&mtu->pdev->dev, "cannot get clock\n");
return PTR_ERR(mtu->clk);
}
ret = clk_prepare(mtu->clk);
if (ret < 0)
goto err_clk_put;
/* Map the memory resource. */
ret = sh_mtu2_map_memory(mtu);
if (ret < 0) {
dev_err(&mtu->pdev->dev, "failed to remap I/O memory\n");
goto err_clk_unprepare;
}
/* Allocate and setup the channels. */
ret = platform_irq_count(pdev);
if (ret < 0)
goto err_unmap;
mtu->num_channels = min_t(unsigned int, ret,
ARRAY_SIZE(sh_mtu2_channel_offsets));
mtu->channels = kcalloc(mtu->num_channels, sizeof(*mtu->channels),
GFP_KERNEL);
if (mtu->channels == NULL) {
ret = -ENOMEM;
goto err_unmap;
}
for (i = 0; i < mtu->num_channels; ++i) {
ret = sh_mtu2_setup_channel(&mtu->channels[i], i, mtu);
if (ret < 0)
goto err_unmap;
}
platform_set_drvdata(pdev, mtu);
return 0;
err_unmap:
kfree(mtu->channels);
iounmap(mtu->mapbase);
err_clk_unprepare:
clk_unprepare(mtu->clk);
err_clk_put:
clk_put(mtu->clk);
return ret;
}
static int sh_mtu2_probe(struct platform_device *pdev)
{
struct sh_mtu2_device *mtu = platform_get_drvdata(pdev);
int ret;
if (!is_sh_early_platform_device(pdev)) {
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
}
if (mtu) {
dev_info(&pdev->dev, "kept as earlytimer\n");
goto out;
}
mtu = kzalloc(sizeof(*mtu), GFP_KERNEL);
if (mtu == NULL)
return -ENOMEM;
ret = sh_mtu2_setup(mtu, pdev);
if (ret) {
kfree(mtu);
pm_runtime_idle(&pdev->dev);
return ret;
}
if (is_sh_early_platform_device(pdev))
return 0;
out:
if (mtu->has_clockevent)
pm_runtime_irq_safe(&pdev->dev);
else
pm_runtime_idle(&pdev->dev);
return 0;
}
static int sh_mtu2_remove(struct platform_device *pdev)
{
return -EBUSY; /* cannot unregister clockevent */
}
static const struct platform_device_id sh_mtu2_id_table[] = {
{ "sh-mtu2", 0 },
{ },
};
MODULE_DEVICE_TABLE(platform, sh_mtu2_id_table);
static const struct of_device_id sh_mtu2_of_table[] __maybe_unused = {
{ .compatible = "renesas,mtu2" },
{ }
};
MODULE_DEVICE_TABLE(of, sh_mtu2_of_table);
static struct platform_driver sh_mtu2_device_driver = {
.probe = sh_mtu2_probe,
.remove = sh_mtu2_remove,
.driver = {
.name = "sh_mtu2",
.of_match_table = of_match_ptr(sh_mtu2_of_table),
},
.id_table = sh_mtu2_id_table,
};
static int __init sh_mtu2_init(void)
{
return platform_driver_register(&sh_mtu2_device_driver);
}
static void __exit sh_mtu2_exit(void)
{
platform_driver_unregister(&sh_mtu2_device_driver);
}
#ifdef CONFIG_SUPERH
sh_early_platform_init("earlytimer", &sh_mtu2_device_driver);
#endif
subsys_initcall(sh_mtu2_init);
module_exit(sh_mtu2_exit);
MODULE_AUTHOR("Magnus Damm");
MODULE_DESCRIPTION("SuperH MTU2 Timer Driver");
MODULE_LICENSE("GPL v2");
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