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-rw-r--r--drivers/clk/imx/clk-imx1.c1
-rw-r--r--drivers/clk/imx/clk-imx27.c1
-rw-r--r--drivers/clk/imx/clk-imx31.c1
-rw-r--r--drivers/clk/imx/clk-imx35.c1
-rw-r--r--drivers/clocksource/Kconfig9
-rw-r--r--drivers/clocksource/Makefile1
-rw-r--r--drivers/clocksource/hyperv_timer.c54
-rw-r--r--drivers/clocksource/ingenic-timer.c10
-rw-r--r--drivers/clocksource/timer-cadence-ttc.c19
-rw-r--r--drivers/clocksource/timer-imx-gpt.c25
-rw-r--r--drivers/clocksource/timer-loongson1-pwm.c236
11 files changed, 298 insertions, 60 deletions
diff --git a/drivers/clk/imx/clk-imx1.c b/drivers/clk/imx/clk-imx1.c
index 22fc7491ba00..f6ea7e5052d5 100644
--- a/drivers/clk/imx/clk-imx1.c
+++ b/drivers/clk/imx/clk-imx1.c
@@ -10,7 +10,6 @@
#include <linux/of.h>
#include <linux/of_address.h>
#include <dt-bindings/clock/imx1-clock.h>
-#include <soc/imx/timer.h>
#include <asm/irq.h>
#include "clk.h"
diff --git a/drivers/clk/imx/clk-imx27.c b/drivers/clk/imx/clk-imx27.c
index 5d177125728d..99618ded0939 100644
--- a/drivers/clk/imx/clk-imx27.c
+++ b/drivers/clk/imx/clk-imx27.c
@@ -8,7 +8,6 @@
#include <linux/of_address.h>
#include <dt-bindings/clock/imx27-clock.h>
#include <soc/imx/revision.h>
-#include <soc/imx/timer.h>
#include <asm/irq.h>
#include "clk.h"
diff --git a/drivers/clk/imx/clk-imx31.c b/drivers/clk/imx/clk-imx31.c
index c44e18c6f63f..4c8d9ff0b2ad 100644
--- a/drivers/clk/imx/clk-imx31.c
+++ b/drivers/clk/imx/clk-imx31.c
@@ -11,7 +11,6 @@
#include <linux/of.h>
#include <linux/of_address.h>
#include <soc/imx/revision.h>
-#include <soc/imx/timer.h>
#include <asm/irq.h>
#include "clk.h"
diff --git a/drivers/clk/imx/clk-imx35.c b/drivers/clk/imx/clk-imx35.c
index 7dcbaea3fea3..3b6fdb4e0be7 100644
--- a/drivers/clk/imx/clk-imx35.c
+++ b/drivers/clk/imx/clk-imx35.c
@@ -10,7 +10,6 @@
#include <linux/of.h>
#include <linux/err.h>
#include <soc/imx/revision.h>
-#include <soc/imx/timer.h>
#include <asm/irq.h>
#include "clk.h"
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 526382dc7482..c4d671a5a13d 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -612,6 +612,15 @@ config TIMER_IMX_SYS_CTR
Enable this option to use i.MX system counter timer as a
clockevent.
+config CLKSRC_LOONGSON1_PWM
+ bool "Clocksource using Loongson1 PWM"
+ depends on MACH_LOONGSON32 || COMPILE_TEST
+ select MIPS_EXTERNAL_TIMER
+ select TIMER_OF
+ help
+ Enable this option to use Loongson1 PWM timer as clocksource
+ instead of the performance counter.
+
config CLKSRC_ST_LPC
bool "Low power clocksource found in the LPC" if COMPILE_TEST
select TIMER_OF if OF
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index f12d3987a960..5d93c9e3fc55 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -89,3 +89,4 @@ obj-$(CONFIG_MICROCHIP_PIT64B) += timer-microchip-pit64b.o
obj-$(CONFIG_MSC313E_TIMER) += timer-msc313e.o
obj-$(CONFIG_GOLDFISH_TIMER) += timer-goldfish.o
obj-$(CONFIG_GXP_TIMER) += timer-gxp.o
+obj-$(CONFIG_CLKSRC_LOONGSON1_PWM) += timer-loongson1-pwm.o
diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c
index bcd9042a0c9f..9fc008c16636 100644
--- a/drivers/clocksource/hyperv_timer.c
+++ b/drivers/clocksource/hyperv_timer.c
@@ -475,15 +475,9 @@ static u64 notrace read_hv_clock_msr_cs(struct clocksource *arg)
return read_hv_clock_msr();
}
-static u64 notrace read_hv_sched_clock_msr(void)
-{
- return (read_hv_clock_msr() - hv_sched_clock_offset) *
- (NSEC_PER_SEC / HV_CLOCK_HZ);
-}
-
static struct clocksource hyperv_cs_msr = {
.name = "hyperv_clocksource_msr",
- .rating = 500,
+ .rating = 495,
.read = read_hv_clock_msr_cs,
.mask = CLOCKSOURCE_MASK(64),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
@@ -513,7 +507,7 @@ static __always_inline void hv_setup_sched_clock(void *sched_clock)
static __always_inline void hv_setup_sched_clock(void *sched_clock) {}
#endif /* CONFIG_GENERIC_SCHED_CLOCK */
-static bool __init hv_init_tsc_clocksource(void)
+static void __init hv_init_tsc_clocksource(void)
{
union hv_reference_tsc_msr tsc_msr;
@@ -524,17 +518,14 @@ static bool __init hv_init_tsc_clocksource(void)
* Hyper-V Reference TSC rating, causing the generic TSC to be used.
* TSC_INVARIANT is not offered on ARM64, so the Hyper-V Reference
* TSC will be preferred over the virtualized ARM64 arch counter.
- * While the Hyper-V MSR clocksource won't be used since the
- * Reference TSC clocksource is present, change its rating as
- * well for consistency.
*/
if (ms_hyperv.features & HV_ACCESS_TSC_INVARIANT) {
hyperv_cs_tsc.rating = 250;
- hyperv_cs_msr.rating = 250;
+ hyperv_cs_msr.rating = 245;
}
if (!(ms_hyperv.features & HV_MSR_REFERENCE_TSC_AVAILABLE))
- return false;
+ return;
hv_read_reference_counter = read_hv_clock_tsc;
@@ -565,33 +556,34 @@ static bool __init hv_init_tsc_clocksource(void)
clocksource_register_hz(&hyperv_cs_tsc, NSEC_PER_SEC/100);
- hv_sched_clock_offset = hv_read_reference_counter();
- hv_setup_sched_clock(read_hv_sched_clock_tsc);
-
- return true;
+ /*
+ * If TSC is invariant, then let it stay as the sched clock since it
+ * will be faster than reading the TSC page. But if not invariant, use
+ * the TSC page so that live migrations across hosts with different
+ * frequencies is handled correctly.
+ */
+ if (!(ms_hyperv.features & HV_ACCESS_TSC_INVARIANT)) {
+ hv_sched_clock_offset = hv_read_reference_counter();
+ hv_setup_sched_clock(read_hv_sched_clock_tsc);
+ }
}
void __init hv_init_clocksource(void)
{
/*
- * Try to set up the TSC page clocksource. If it succeeds, we're
- * done. Otherwise, set up the MSR clocksource. At least one of
- * these will always be available except on very old versions of
- * Hyper-V on x86. In that case we won't have a Hyper-V
+ * Try to set up the TSC page clocksource, then the MSR clocksource.
+ * At least one of these will always be available except on very old
+ * versions of Hyper-V on x86. In that case we won't have a Hyper-V
* clocksource, but Linux will still run with a clocksource based
* on the emulated PIT or LAPIC timer.
+ *
+ * Never use the MSR clocksource as sched clock. It's too slow.
+ * Better to use the native sched clock as the fallback.
*/
- if (hv_init_tsc_clocksource())
- return;
-
- if (!(ms_hyperv.features & HV_MSR_TIME_REF_COUNT_AVAILABLE))
- return;
-
- hv_read_reference_counter = read_hv_clock_msr;
- clocksource_register_hz(&hyperv_cs_msr, NSEC_PER_SEC/100);
+ hv_init_tsc_clocksource();
- hv_sched_clock_offset = hv_read_reference_counter();
- hv_setup_sched_clock(read_hv_sched_clock_msr);
+ if (ms_hyperv.features & HV_MSR_TIME_REF_COUNT_AVAILABLE)
+ clocksource_register_hz(&hyperv_cs_msr, NSEC_PER_SEC/100);
}
void __init hv_remap_tsc_clocksource(void)
diff --git a/drivers/clocksource/ingenic-timer.c b/drivers/clocksource/ingenic-timer.c
index 089ce64b1c3f..154ee5f7954a 100644
--- a/drivers/clocksource/ingenic-timer.c
+++ b/drivers/clocksource/ingenic-timer.c
@@ -369,7 +369,7 @@ static int __init ingenic_tcu_probe(struct platform_device *pdev)
return 0;
}
-static int __maybe_unused ingenic_tcu_suspend(struct device *dev)
+static int ingenic_tcu_suspend(struct device *dev)
{
struct ingenic_tcu *tcu = dev_get_drvdata(dev);
unsigned int cpu;
@@ -382,7 +382,7 @@ static int __maybe_unused ingenic_tcu_suspend(struct device *dev)
return 0;
}
-static int __maybe_unused ingenic_tcu_resume(struct device *dev)
+static int ingenic_tcu_resume(struct device *dev)
{
struct ingenic_tcu *tcu = dev_get_drvdata(dev);
unsigned int cpu;
@@ -406,7 +406,7 @@ err_timer_clk_disable:
return ret;
}
-static const struct dev_pm_ops __maybe_unused ingenic_tcu_pm_ops = {
+static const struct dev_pm_ops ingenic_tcu_pm_ops = {
/* _noirq: We want the TCU clocks to be gated last / ungated first */
.suspend_noirq = ingenic_tcu_suspend,
.resume_noirq = ingenic_tcu_resume,
@@ -415,9 +415,7 @@ static const struct dev_pm_ops __maybe_unused ingenic_tcu_pm_ops = {
static struct platform_driver ingenic_tcu_driver = {
.driver = {
.name = "ingenic-tcu-timer",
-#ifdef CONFIG_PM_SLEEP
- .pm = &ingenic_tcu_pm_ops,
-#endif
+ .pm = pm_sleep_ptr(&ingenic_tcu_pm_ops),
.of_match_table = ingenic_tcu_of_match,
},
};
diff --git a/drivers/clocksource/timer-cadence-ttc.c b/drivers/clocksource/timer-cadence-ttc.c
index 4efd0cf3b602..0d52e28fea4d 100644
--- a/drivers/clocksource/timer-cadence-ttc.c
+++ b/drivers/clocksource/timer-cadence-ttc.c
@@ -486,10 +486,10 @@ static int __init ttc_timer_probe(struct platform_device *pdev)
* and use it. Note that the event timer uses the interrupt and it's the
* 2nd TTC hence the irq_of_parse_and_map(,1)
*/
- timer_baseaddr = of_iomap(timer, 0);
- if (!timer_baseaddr) {
+ timer_baseaddr = devm_of_iomap(&pdev->dev, timer, 0, NULL);
+ if (IS_ERR(timer_baseaddr)) {
pr_err("ERROR: invalid timer base address\n");
- return -ENXIO;
+ return PTR_ERR(timer_baseaddr);
}
irq = irq_of_parse_and_map(timer, 1);
@@ -513,20 +513,27 @@ static int __init ttc_timer_probe(struct platform_device *pdev)
clk_ce = of_clk_get(timer, clksel);
if (IS_ERR(clk_ce)) {
pr_err("ERROR: timer input clock not found\n");
- return PTR_ERR(clk_ce);
+ ret = PTR_ERR(clk_ce);
+ goto put_clk_cs;
}
ret = ttc_setup_clocksource(clk_cs, timer_baseaddr, timer_width);
if (ret)
- return ret;
+ goto put_clk_ce;
ret = ttc_setup_clockevent(clk_ce, timer_baseaddr + 4, irq);
if (ret)
- return ret;
+ goto put_clk_ce;
pr_info("%pOFn #0 at %p, irq=%d\n", timer, timer_baseaddr, irq);
return 0;
+
+put_clk_ce:
+ clk_put(clk_ce);
+put_clk_cs:
+ clk_put(clk_cs);
+ return ret;
}
static const struct of_device_id ttc_timer_of_match[] = {
diff --git a/drivers/clocksource/timer-imx-gpt.c b/drivers/clocksource/timer-imx-gpt.c
index ca3e4cbc80c6..28ab4f1a7c71 100644
--- a/drivers/clocksource/timer-imx-gpt.c
+++ b/drivers/clocksource/timer-imx-gpt.c
@@ -16,7 +16,6 @@
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
-#include <soc/imx/timer.h>
/*
* There are 4 versions of the timer hardware on Freescale MXC hardware.
@@ -25,6 +24,12 @@
* - MX25, MX31, MX35, MX37, MX51, MX6Q(rev1.0)
* - MX6DL, MX6SX, MX6Q(rev1.1+)
*/
+enum imx_gpt_type {
+ GPT_TYPE_IMX1, /* i.MX1 */
+ GPT_TYPE_IMX21, /* i.MX21/27 */
+ GPT_TYPE_IMX31, /* i.MX31/35/25/37/51/6Q */
+ GPT_TYPE_IMX6DL, /* i.MX6DL/SX/SL */
+};
/* defines common for all i.MX */
#define MXC_TCTL 0x00
@@ -93,13 +98,11 @@ static void imx1_gpt_irq_disable(struct imx_timer *imxtm)
tmp = readl_relaxed(imxtm->base + MXC_TCTL);
writel_relaxed(tmp & ~MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL);
}
-#define imx21_gpt_irq_disable imx1_gpt_irq_disable
static void imx31_gpt_irq_disable(struct imx_timer *imxtm)
{
writel_relaxed(0, imxtm->base + V2_IR);
}
-#define imx6dl_gpt_irq_disable imx31_gpt_irq_disable
static void imx1_gpt_irq_enable(struct imx_timer *imxtm)
{
@@ -108,13 +111,11 @@ static void imx1_gpt_irq_enable(struct imx_timer *imxtm)
tmp = readl_relaxed(imxtm->base + MXC_TCTL);
writel_relaxed(tmp | MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL);
}
-#define imx21_gpt_irq_enable imx1_gpt_irq_enable
static void imx31_gpt_irq_enable(struct imx_timer *imxtm)
{
writel_relaxed(1<<0, imxtm->base + V2_IR);
}
-#define imx6dl_gpt_irq_enable imx31_gpt_irq_enable
static void imx1_gpt_irq_acknowledge(struct imx_timer *imxtm)
{
@@ -131,7 +132,6 @@ static void imx31_gpt_irq_acknowledge(struct imx_timer *imxtm)
{
writel_relaxed(V2_TSTAT_OF1, imxtm->base + V2_TSTAT);
}
-#define imx6dl_gpt_irq_acknowledge imx31_gpt_irq_acknowledge
static void __iomem *sched_clock_reg;
@@ -296,7 +296,6 @@ static void imx1_gpt_setup_tctl(struct imx_timer *imxtm)
tctl_val = MX1_2_TCTL_FRR | MX1_2_TCTL_CLK_PCLK1 | MXC_TCTL_TEN;
writel_relaxed(tctl_val, imxtm->base + MXC_TCTL);
}
-#define imx21_gpt_setup_tctl imx1_gpt_setup_tctl
static void imx31_gpt_setup_tctl(struct imx_timer *imxtm)
{
@@ -343,10 +342,10 @@ static const struct imx_gpt_data imx21_gpt_data = {
.reg_tstat = MX1_2_TSTAT,
.reg_tcn = MX1_2_TCN,
.reg_tcmp = MX1_2_TCMP,
- .gpt_irq_enable = imx21_gpt_irq_enable,
- .gpt_irq_disable = imx21_gpt_irq_disable,
+ .gpt_irq_enable = imx1_gpt_irq_enable,
+ .gpt_irq_disable = imx1_gpt_irq_disable,
.gpt_irq_acknowledge = imx21_gpt_irq_acknowledge,
- .gpt_setup_tctl = imx21_gpt_setup_tctl,
+ .gpt_setup_tctl = imx1_gpt_setup_tctl,
.set_next_event = mx1_2_set_next_event,
};
@@ -365,9 +364,9 @@ static const struct imx_gpt_data imx6dl_gpt_data = {
.reg_tstat = V2_TSTAT,
.reg_tcn = V2_TCN,
.reg_tcmp = V2_TCMP,
- .gpt_irq_enable = imx6dl_gpt_irq_enable,
- .gpt_irq_disable = imx6dl_gpt_irq_disable,
- .gpt_irq_acknowledge = imx6dl_gpt_irq_acknowledge,
+ .gpt_irq_enable = imx31_gpt_irq_enable,
+ .gpt_irq_disable = imx31_gpt_irq_disable,
+ .gpt_irq_acknowledge = imx31_gpt_irq_acknowledge,
.gpt_setup_tctl = imx6dl_gpt_setup_tctl,
.set_next_event = v2_set_next_event,
};
diff --git a/drivers/clocksource/timer-loongson1-pwm.c b/drivers/clocksource/timer-loongson1-pwm.c
new file mode 100644
index 000000000000..6335fee03017
--- /dev/null
+++ b/drivers/clocksource/timer-loongson1-pwm.c
@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Clocksource driver for Loongson-1 SoC
+ *
+ * Copyright (c) 2023 Keguang Zhang <keguang.zhang@gmail.com>
+ */
+
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/sizes.h>
+#include "timer-of.h"
+
+/* Loongson-1 PWM Timer Register Definitions */
+#define PWM_CNTR 0x0
+#define PWM_HRC 0x4
+#define PWM_LRC 0x8
+#define PWM_CTRL 0xc
+
+/* PWM Control Register Bits */
+#define INT_LRC_EN BIT(11)
+#define INT_HRC_EN BIT(10)
+#define CNTR_RST BIT(7)
+#define INT_SR BIT(6)
+#define INT_EN BIT(5)
+#define PWM_SINGLE BIT(4)
+#define PWM_OE BIT(3)
+#define CNT_EN BIT(0)
+
+#define CNTR_WIDTH 24
+
+DEFINE_RAW_SPINLOCK(ls1x_timer_lock);
+
+struct ls1x_clocksource {
+ void __iomem *reg_base;
+ unsigned long ticks_per_jiffy;
+ struct clocksource clksrc;
+};
+
+static inline struct ls1x_clocksource *to_ls1x_clksrc(struct clocksource *c)
+{
+ return container_of(c, struct ls1x_clocksource, clksrc);
+}
+
+static inline void ls1x_pwmtimer_set_period(unsigned int period,
+ struct timer_of *to)
+{
+ writel(period, timer_of_base(to) + PWM_LRC);
+ writel(period, timer_of_base(to) + PWM_HRC);
+}
+
+static inline void ls1x_pwmtimer_clear(struct timer_of *to)
+{
+ writel(0, timer_of_base(to) + PWM_CNTR);
+}
+
+static inline void ls1x_pwmtimer_start(struct timer_of *to)
+{
+ writel((INT_EN | PWM_OE | CNT_EN), timer_of_base(to) + PWM_CTRL);
+}
+
+static inline void ls1x_pwmtimer_stop(struct timer_of *to)
+{
+ writel(0, timer_of_base(to) + PWM_CTRL);
+}
+
+static inline void ls1x_pwmtimer_irq_ack(struct timer_of *to)
+{
+ int val;
+
+ val = readl(timer_of_base(to) + PWM_CTRL);
+ val |= INT_SR;
+ writel(val, timer_of_base(to) + PWM_CTRL);
+}
+
+static irqreturn_t ls1x_clockevent_isr(int irq, void *dev_id)
+{
+ struct clock_event_device *clkevt = dev_id;
+ struct timer_of *to = to_timer_of(clkevt);
+
+ ls1x_pwmtimer_irq_ack(to);
+ ls1x_pwmtimer_clear(to);
+ ls1x_pwmtimer_start(to);
+
+ clkevt->event_handler(clkevt);
+
+ return IRQ_HANDLED;
+}
+
+static int ls1x_clockevent_set_state_periodic(struct clock_event_device *clkevt)
+{
+ struct timer_of *to = to_timer_of(clkevt);
+
+ raw_spin_lock(&ls1x_timer_lock);
+ ls1x_pwmtimer_set_period(timer_of_period(to), to);
+ ls1x_pwmtimer_clear(to);
+ ls1x_pwmtimer_start(to);
+ raw_spin_unlock(&ls1x_timer_lock);
+
+ return 0;
+}
+
+static int ls1x_clockevent_tick_resume(struct clock_event_device *clkevt)
+{
+ raw_spin_lock(&ls1x_timer_lock);
+ ls1x_pwmtimer_start(to_timer_of(clkevt));
+ raw_spin_unlock(&ls1x_timer_lock);
+
+ return 0;
+}
+
+static int ls1x_clockevent_set_state_shutdown(struct clock_event_device *clkevt)
+{
+ raw_spin_lock(&ls1x_timer_lock);
+ ls1x_pwmtimer_stop(to_timer_of(clkevt));
+ raw_spin_unlock(&ls1x_timer_lock);
+
+ return 0;
+}
+
+static int ls1x_clockevent_set_next(unsigned long evt,
+ struct clock_event_device *clkevt)
+{
+ struct timer_of *to = to_timer_of(clkevt);
+
+ raw_spin_lock(&ls1x_timer_lock);
+ ls1x_pwmtimer_set_period(evt, to);
+ ls1x_pwmtimer_clear(to);
+ ls1x_pwmtimer_start(to);
+ raw_spin_unlock(&ls1x_timer_lock);
+
+ return 0;
+}
+
+static struct timer_of ls1x_to = {
+ .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
+ .clkevt = {
+ .name = "ls1x-pwmtimer",
+ .features = CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 300,
+ .set_next_event = ls1x_clockevent_set_next,
+ .set_state_periodic = ls1x_clockevent_set_state_periodic,
+ .set_state_oneshot = ls1x_clockevent_set_state_shutdown,
+ .set_state_shutdown = ls1x_clockevent_set_state_shutdown,
+ .tick_resume = ls1x_clockevent_tick_resume,
+ },
+ .of_irq = {
+ .handler = ls1x_clockevent_isr,
+ .flags = IRQF_TIMER,
+ },
+};
+
+/*
+ * Since the PWM timer overflows every two ticks, its not very useful
+ * to just read by itself. So use jiffies to emulate a free
+ * running counter:
+ */
+static u64 ls1x_clocksource_read(struct clocksource *cs)
+{
+ struct ls1x_clocksource *ls1x_cs = to_ls1x_clksrc(cs);
+ unsigned long flags;
+ int count;
+ u32 jifs;
+ static int old_count;
+ static u32 old_jifs;
+
+ raw_spin_lock_irqsave(&ls1x_timer_lock, flags);
+ /*
+ * Although our caller may have the read side of xtime_lock,
+ * this is now a seqlock, and we are cheating in this routine
+ * by having side effects on state that we cannot undo if
+ * there is a collision on the seqlock and our caller has to
+ * retry. (Namely, old_jifs and old_count.) So we must treat
+ * jiffies as volatile despite the lock. We read jiffies
+ * before latching the timer count to guarantee that although
+ * the jiffies value might be older than the count (that is,
+ * the counter may underflow between the last point where
+ * jiffies was incremented and the point where we latch the
+ * count), it cannot be newer.
+ */
+ jifs = jiffies;
+ /* read the count */
+ count = readl(ls1x_cs->reg_base + PWM_CNTR);
+
+ /*
+ * It's possible for count to appear to go the wrong way for this
+ * reason:
+ *
+ * The timer counter underflows, but we haven't handled the resulting
+ * interrupt and incremented jiffies yet.
+ *
+ * Previous attempts to handle these cases intelligently were buggy, so
+ * we just do the simple thing now.
+ */
+ if (count < old_count && jifs == old_jifs)
+ count = old_count;
+
+ old_count = count;
+ old_jifs = jifs;
+
+ raw_spin_unlock_irqrestore(&ls1x_timer_lock, flags);
+
+ return (u64)(jifs * ls1x_cs->ticks_per_jiffy) + count;
+}
+
+static struct ls1x_clocksource ls1x_clocksource = {
+ .clksrc = {
+ .name = "ls1x-pwmtimer",
+ .rating = 300,
+ .read = ls1x_clocksource_read,
+ .mask = CLOCKSOURCE_MASK(CNTR_WIDTH),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+ },
+};
+
+static int __init ls1x_pwm_clocksource_init(struct device_node *np)
+{
+ struct timer_of *to = &ls1x_to;
+ int ret;
+
+ ret = timer_of_init(np, to);
+ if (ret)
+ return ret;
+
+ clockevents_config_and_register(&to->clkevt, timer_of_rate(to),
+ 0x1, GENMASK(CNTR_WIDTH - 1, 0));
+
+ ls1x_clocksource.reg_base = timer_of_base(to);
+ ls1x_clocksource.ticks_per_jiffy = timer_of_period(to);
+
+ return clocksource_register_hz(&ls1x_clocksource.clksrc,
+ timer_of_rate(to));
+}
+
+TIMER_OF_DECLARE(ls1x_pwm_clocksource, "loongson,ls1b-pwmtimer",
+ ls1x_pwm_clocksource_init);