* [PATCH v4 1/3] MIPS: Loongson32: Remove deprecated PWM timer clocksource
2023-05-12 10:37 [PATCH v4 0/3] Move Loongson1 PWM timer to clocksource framework Keguang Zhang
@ 2023-05-12 10:37 ` Keguang Zhang
2023-05-12 10:37 ` [PATCH v4 2/3] dt-bindings: timer: Add Loongson-1 clocksource Keguang Zhang
2023-05-12 10:37 ` [PATCH v4 3/3] clocksource: loongson1: Move PWM timer to clocksource framework Keguang Zhang
2 siblings, 0 replies; 5+ messages in thread
From: Keguang Zhang @ 2023-05-12 10:37 UTC (permalink / raw)
To: linux-kernel, devicetree, linux-mips
Cc: Daniel Lezcano, Thomas Gleixner, Rob Herring, Krzysztof Kozlowski,
Thomas Bogendoerfer, Stephen Boyd, Keguang Zhang
The Loongson1 PWM timer will be moved to clocksource framework.
Then, the old driver is no longer needed.
Remove the deprecated code and update the Kconfig.
Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>
---
V3 -> V4: None
V2 -> V3: Remove the reference to regs-pwm.h
V1 -> V2: Delete the obsolete header file regs-pwm.h
---
.../include/asm/mach-loongson32/loongson1.h | 1 -
.../include/asm/mach-loongson32/regs-pwm.h | 25 ---
arch/mips/loongson32/Kconfig | 37 ---
arch/mips/loongson32/common/time.c | 210 ------------------
4 files changed, 273 deletions(-)
delete mode 100644 arch/mips/include/asm/mach-loongson32/regs-pwm.h
diff --git a/arch/mips/include/asm/mach-loongson32/loongson1.h b/arch/mips/include/asm/mach-loongson32/loongson1.h
index eb3ddbec1752..d8f9dec0ecc3 100644
--- a/arch/mips/include/asm/mach-loongson32/loongson1.h
+++ b/arch/mips/include/asm/mach-loongson32/loongson1.h
@@ -47,7 +47,6 @@
#include <regs-clk.h>
#include <regs-mux.h>
-#include <regs-pwm.h>
#include <regs-rtc.h>
#include <regs-wdt.h>
diff --git a/arch/mips/include/asm/mach-loongson32/regs-pwm.h b/arch/mips/include/asm/mach-loongson32/regs-pwm.h
deleted file mode 100644
index ec870c82d492..000000000000
--- a/arch/mips/include/asm/mach-loongson32/regs-pwm.h
+++ /dev/null
@@ -1,25 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/*
- * Copyright (c) 2014 Zhang, Keguang <keguang.zhang@gmail.com>
- *
- * Loongson 1 PWM Register Definitions.
- */
-
-#ifndef __ASM_MACH_LOONGSON32_REGS_PWM_H
-#define __ASM_MACH_LOONGSON32_REGS_PWM_H
-
-/* Loongson 1 PWM Timer Register Definitions */
-#define PWM_CNT 0x0
-#define PWM_HRC 0x4
-#define PWM_LRC 0x8
-#define PWM_CTRL 0xc
-
-/* PWM Control Register Bits */
-#define CNT_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)
-
-#endif /* __ASM_MACH_LOONGSON32_REGS_PWM_H */
diff --git a/arch/mips/loongson32/Kconfig b/arch/mips/loongson32/Kconfig
index 2ef9da0016df..a7c500959577 100644
--- a/arch/mips/loongson32/Kconfig
+++ b/arch/mips/loongson32/Kconfig
@@ -35,41 +35,4 @@ config LOONGSON1_LS1C
select COMMON_CLK
endchoice
-menuconfig CEVT_CSRC_LS1X
- bool "Use PWM Timer for clockevent/clocksource"
- select MIPS_EXTERNAL_TIMER
- depends on CPU_LOONGSON32
- help
- This option changes the default clockevent/clocksource to PWM Timer,
- and is required by Loongson1 CPUFreq support.
-
- If unsure, say N.
-
-choice
- prompt "Select clockevent/clocksource"
- depends on CEVT_CSRC_LS1X
- default TIMER_USE_PWM0
-
-config TIMER_USE_PWM0
- bool "Use PWM Timer 0"
- help
- Use PWM Timer 0 as the default clockevent/clocksourcer.
-
-config TIMER_USE_PWM1
- bool "Use PWM Timer 1"
- help
- Use PWM Timer 1 as the default clockevent/clocksourcer.
-
-config TIMER_USE_PWM2
- bool "Use PWM Timer 2"
- help
- Use PWM Timer 2 as the default clockevent/clocksourcer.
-
-config TIMER_USE_PWM3
- bool "Use PWM Timer 3"
- help
- Use PWM Timer 3 as the default clockevent/clocksourcer.
-
-endchoice
-
endif # MACH_LOONGSON32
diff --git a/arch/mips/loongson32/common/time.c b/arch/mips/loongson32/common/time.c
index 965c04aa56fd..74ad2b17918d 100644
--- a/arch/mips/loongson32/common/time.c
+++ b/arch/mips/loongson32/common/time.c
@@ -5,208 +5,8 @@
#include <linux/clk.h>
#include <linux/of_clk.h>
-#include <linux/interrupt.h>
-#include <linux/sizes.h>
#include <asm/time.h>
-#include <loongson1.h>
-#include <platform.h>
-
-#ifdef CONFIG_CEVT_CSRC_LS1X
-
-#if defined(CONFIG_TIMER_USE_PWM1)
-#define LS1X_TIMER_BASE LS1X_PWM1_BASE
-#define LS1X_TIMER_IRQ LS1X_PWM1_IRQ
-
-#elif defined(CONFIG_TIMER_USE_PWM2)
-#define LS1X_TIMER_BASE LS1X_PWM2_BASE
-#define LS1X_TIMER_IRQ LS1X_PWM2_IRQ
-
-#elif defined(CONFIG_TIMER_USE_PWM3)
-#define LS1X_TIMER_BASE LS1X_PWM3_BASE
-#define LS1X_TIMER_IRQ LS1X_PWM3_IRQ
-
-#else
-#define LS1X_TIMER_BASE LS1X_PWM0_BASE
-#define LS1X_TIMER_IRQ LS1X_PWM0_IRQ
-#endif
-
-DEFINE_RAW_SPINLOCK(ls1x_timer_lock);
-
-static void __iomem *timer_reg_base;
-static uint32_t ls1x_jiffies_per_tick;
-
-static inline void ls1x_pwmtimer_set_period(uint32_t period)
-{
- __raw_writel(period, timer_reg_base + PWM_HRC);
- __raw_writel(period, timer_reg_base + PWM_LRC);
-}
-
-static inline void ls1x_pwmtimer_restart(void)
-{
- __raw_writel(0x0, timer_reg_base + PWM_CNT);
- __raw_writel(INT_EN | CNT_EN, timer_reg_base + PWM_CTRL);
-}
-
-void __init ls1x_pwmtimer_init(void)
-{
- timer_reg_base = ioremap(LS1X_TIMER_BASE, SZ_16);
- if (!timer_reg_base)
- panic("Failed to remap timer registers");
-
- ls1x_jiffies_per_tick = DIV_ROUND_CLOSEST(mips_hpt_frequency, HZ);
-
- ls1x_pwmtimer_set_period(ls1x_jiffies_per_tick);
- ls1x_pwmtimer_restart();
-}
-
-static u64 ls1x_clocksource_read(struct clocksource *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 = __raw_readl(timer_reg_base + PWM_CNT);
-
- /*
- * 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_jiffies_per_tick) + count;
-}
-
-static struct clocksource ls1x_clocksource = {
- .name = "ls1x-pwmtimer",
- .read = ls1x_clocksource_read,
- .mask = CLOCKSOURCE_MASK(24),
- .flags = CLOCK_SOURCE_IS_CONTINUOUS,
-};
-
-static irqreturn_t ls1x_clockevent_isr(int irq, void *devid)
-{
- struct clock_event_device *cd = devid;
-
- ls1x_pwmtimer_restart();
- cd->event_handler(cd);
-
- return IRQ_HANDLED;
-}
-
-static int ls1x_clockevent_set_state_periodic(struct clock_event_device *cd)
-{
- raw_spin_lock(&ls1x_timer_lock);
- ls1x_pwmtimer_set_period(ls1x_jiffies_per_tick);
- ls1x_pwmtimer_restart();
- __raw_writel(INT_EN | CNT_EN, timer_reg_base + PWM_CTRL);
- raw_spin_unlock(&ls1x_timer_lock);
-
- return 0;
-}
-
-static int ls1x_clockevent_tick_resume(struct clock_event_device *cd)
-{
- raw_spin_lock(&ls1x_timer_lock);
- __raw_writel(INT_EN | CNT_EN, timer_reg_base + PWM_CTRL);
- raw_spin_unlock(&ls1x_timer_lock);
-
- return 0;
-}
-
-static int ls1x_clockevent_set_state_shutdown(struct clock_event_device *cd)
-{
- raw_spin_lock(&ls1x_timer_lock);
- __raw_writel(__raw_readl(timer_reg_base + PWM_CTRL) & ~CNT_EN,
- timer_reg_base + PWM_CTRL);
- raw_spin_unlock(&ls1x_timer_lock);
-
- return 0;
-}
-
-static int ls1x_clockevent_set_next(unsigned long evt,
- struct clock_event_device *cd)
-{
- raw_spin_lock(&ls1x_timer_lock);
- ls1x_pwmtimer_set_period(evt);
- ls1x_pwmtimer_restart();
- raw_spin_unlock(&ls1x_timer_lock);
-
- return 0;
-}
-
-static struct clock_event_device ls1x_clockevent = {
- .name = "ls1x-pwmtimer",
- .features = CLOCK_EVT_FEAT_PERIODIC,
- .rating = 300,
- .irq = LS1X_TIMER_IRQ,
- .set_next_event = ls1x_clockevent_set_next,
- .set_state_shutdown = ls1x_clockevent_set_state_shutdown,
- .set_state_periodic = ls1x_clockevent_set_state_periodic,
- .set_state_oneshot = ls1x_clockevent_set_state_shutdown,
- .tick_resume = ls1x_clockevent_tick_resume,
-};
-
-static void __init ls1x_time_init(void)
-{
- struct clock_event_device *cd = &ls1x_clockevent;
- int ret;
-
- if (!mips_hpt_frequency)
- panic("Invalid timer clock rate");
-
- ls1x_pwmtimer_init();
-
- clockevent_set_clock(cd, mips_hpt_frequency);
- cd->max_delta_ns = clockevent_delta2ns(0xffffff, cd);
- cd->max_delta_ticks = 0xffffff;
- cd->min_delta_ns = clockevent_delta2ns(0x000300, cd);
- cd->min_delta_ticks = 0x000300;
- cd->cpumask = cpumask_of(smp_processor_id());
- clockevents_register_device(cd);
-
- ls1x_clocksource.rating = 200 + mips_hpt_frequency / 10000000;
- ret = clocksource_register_hz(&ls1x_clocksource, mips_hpt_frequency);
- if (ret)
- panic(KERN_ERR "Failed to register clocksource: %d\n", ret);
-
- if (request_irq(LS1X_TIMER_IRQ, ls1x_clockevent_isr,
- IRQF_PERCPU | IRQF_TIMER, "ls1x-pwmtimer",
- &ls1x_clockevent))
- pr_err("Failed to register ls1x-pwmtimer interrupt\n");
-}
-#endif /* CONFIG_CEVT_CSRC_LS1X */
-
void __init plat_time_init(void)
{
struct clk *clk = NULL;
@@ -214,20 +14,10 @@ void __init plat_time_init(void)
/* initialize LS1X clocks */
of_clk_init(NULL);
-#ifdef CONFIG_CEVT_CSRC_LS1X
- /* setup LS1X PWM timer */
- clk = clk_get(NULL, "ls1x-pwmtimer");
- if (IS_ERR(clk))
- panic("unable to get timer clock, err=%ld", PTR_ERR(clk));
-
- mips_hpt_frequency = clk_get_rate(clk);
- ls1x_time_init();
-#else
/* setup mips r4k timer */
clk = clk_get(NULL, "cpu_clk");
if (IS_ERR(clk))
panic("unable to get cpu clock, err=%ld", PTR_ERR(clk));
mips_hpt_frequency = clk_get_rate(clk) / 2;
-#endif /* CONFIG_CEVT_CSRC_LS1X */
}
--
2.39.2
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v4 2/3] dt-bindings: timer: Add Loongson-1 clocksource
2023-05-12 10:37 [PATCH v4 0/3] Move Loongson1 PWM timer to clocksource framework Keguang Zhang
2023-05-12 10:37 ` [PATCH v4 1/3] MIPS: Loongson32: Remove deprecated PWM timer clocksource Keguang Zhang
@ 2023-05-12 10:37 ` Keguang Zhang
2023-05-13 9:35 ` Krzysztof Kozlowski
2023-05-12 10:37 ` [PATCH v4 3/3] clocksource: loongson1: Move PWM timer to clocksource framework Keguang Zhang
2 siblings, 1 reply; 5+ messages in thread
From: Keguang Zhang @ 2023-05-12 10:37 UTC (permalink / raw)
To: linux-kernel, devicetree, linux-mips
Cc: Daniel Lezcano, Thomas Gleixner, Rob Herring, Krzysztof Kozlowski,
Thomas Bogendoerfer, Stephen Boyd, Keguang Zhang
Add devicetree binding document for Loongson-1 clocksource.
Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>
---
V3 -> V4: Replaced the wildcard compatible string with specific one
V2 -> V3: None
V1 -> V2: None
---
.../timer/loongson,ls1x-pwmtimer.yaml | 48 +++++++++++++++++++
1 file changed, 48 insertions(+)
create mode 100644 Documentation/devicetree/bindings/timer/loongson,ls1x-pwmtimer.yaml
diff --git a/Documentation/devicetree/bindings/timer/loongson,ls1x-pwmtimer.yaml b/Documentation/devicetree/bindings/timer/loongson,ls1x-pwmtimer.yaml
new file mode 100644
index 000000000000..ad61ae55850b
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/loongson,ls1x-pwmtimer.yaml
@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/timer/loongson,ls1x-pwmtimer.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Loongson-1 PWM timer
+
+maintainers:
+ - Keguang Zhang <keguang.zhang@gmail.com>
+
+description:
+ Loongson-1 PWM timer can be used for system clock source
+ and clock event timers.
+
+properties:
+ compatible:
+ const: loongson,ls1b-pwmtimer
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+ - clocks
+ - interrupts
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/clock/loongson,ls1x-clk.h>
+ #include <dt-bindings/interrupt-controller/irq.h>
+ clocksource: timer@1fe5c030 {
+ compatible = "loongson,ls1b-pwmtimer";
+ reg = <0x1fe5c030 0x10>;
+
+ clocks = <&clkc LS1X_CLKID_APB>;
+ interrupt-parent = <&intc0>;
+ interrupts = <20 IRQ_TYPE_LEVEL_HIGH>;
+ };
--
2.39.2
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH v4 2/3] dt-bindings: timer: Add Loongson-1 clocksource
2023-05-12 10:37 ` [PATCH v4 2/3] dt-bindings: timer: Add Loongson-1 clocksource Keguang Zhang
@ 2023-05-13 9:35 ` Krzysztof Kozlowski
0 siblings, 0 replies; 5+ messages in thread
From: Krzysztof Kozlowski @ 2023-05-13 9:35 UTC (permalink / raw)
To: Keguang Zhang, linux-kernel, devicetree, linux-mips
Cc: Daniel Lezcano, Thomas Gleixner, Rob Herring, Krzysztof Kozlowski,
Thomas Bogendoerfer, Stephen Boyd
On 12/05/2023 12:37, Keguang Zhang wrote:
> Add devicetree binding document for Loongson-1 clocksource.
>
> Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>
> ---
> V3 -> V4: Replaced the wildcard compatible string with specific one
> V2 -> V3: None
> V1 -> V2: None
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Best regards,
Krzysztof
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v4 3/3] clocksource: loongson1: Move PWM timer to clocksource framework
2023-05-12 10:37 [PATCH v4 0/3] Move Loongson1 PWM timer to clocksource framework Keguang Zhang
2023-05-12 10:37 ` [PATCH v4 1/3] MIPS: Loongson32: Remove deprecated PWM timer clocksource Keguang Zhang
2023-05-12 10:37 ` [PATCH v4 2/3] dt-bindings: timer: Add Loongson-1 clocksource Keguang Zhang
@ 2023-05-12 10:37 ` Keguang Zhang
2 siblings, 0 replies; 5+ messages in thread
From: Keguang Zhang @ 2023-05-12 10:37 UTC (permalink / raw)
To: linux-kernel, devicetree, linux-mips
Cc: Daniel Lezcano, Thomas Gleixner, Rob Herring, Krzysztof Kozlowski,
Thomas Bogendoerfer, Stephen Boyd, Keguang Zhang
This patch moves most part of arch/mips/loongson32/common/time.c
into drivers/clocksource.
Adapt the driver to clocksource framework with devicetree support
and updates Kconfig/Makefile options.
Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>
---
V3 -> V4: Change the wildcard compatible string to the specific one
V2 -> V3: None
V1 -> V2: None
---
drivers/clocksource/Kconfig | 9 +
drivers/clocksource/Makefile | 1 +
drivers/clocksource/timer-loongson1-pwm.c | 236 ++++++++++++++++++++++
3 files changed, 246 insertions(+)
create mode 100644 drivers/clocksource/timer-loongson1-pwm.c
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 5fc8f0e7fb38..6e37b26d532d 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -603,6 +603,15 @@ 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 64ab547de97b..f969a9eedfca 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -88,3 +88,4 @@ 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/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);
--
2.39.2
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