2023-12-19 14:55:18

by Xingyu Wu

[permalink] [raw]
Subject: [PATCH v8 0/3] Add timer driver for StarFive JH7110 RISC-V SoC

This patch serises are to add timer driver for the StarFive JH7110
RISC-V SoC. The first patch adds documentation to describe device
tree bindings. The subsequent patch adds timer driver and support
JH7110 SoC. The last patch adds device node about timer in JH7110
dts.

This timer has four free-running 32 bit counters and runs in 24MHz
clock on StarFive JH7110 SoC. And each channel(counter) triggers
an interrupt when timeout. They support one-shot mode and
continuous-run mode.

This timer is used as global timer and register clockevent for each
CPU core after riscv-timer registration on the StarFive JH7110 SoC.

Changes since v7:
- Rebased on 6.7-rc6.
- Modified the Kconfig file and added selection in SOC_STARFIVE.
- Used the timer as a global timer and registered as clockevent
for each CPU core.
- Dropped the timeout function in the interrupt handler callback.
- Changed the way in the functions of jh7110_timer_tick_resume() and
jh7110_timer_resume().
- Dropped the registration of clocksource in the probe.

v7: https://lore.kernel.org/all/[email protected]/

Changes since v6:
- Rebased on 6.6-rc6.
- Used sizeof() instead of the numbers of characters about names.
- Added devm_add_action_or_reset() to release the resets and
clocksources in the case of remove or error in the probe.
- Added flags to check each clocksource is suceessfully registered and
used in the release function.
- Dropped the variable of irq in the jh7110_clkevt struct.
- Dropped the wrappers and used enum definitions and writel() calls
directly.

v6: https://lore.kernel.org/all/[email protected]/

Changes since v5:
- Rebased on 6.6-rc5.
- Changed the number about characters of name.
- Made the clkevt->periodic to a local variable.
- Dropped the variables of device and base.
- Used clkevt->evt.irq directly and dropped the extra copy of irq.

V5: https://lore.kernel.org/all/[email protected]/

Changes since v4:
- Rebased on 6.5.
- Dropped the useless enum and used value directly when writing
registers.
- Modified the description in Kconfig.
- Add the reviewed tag in patch 3.

v4: https://lore.kernel.org/all/[email protected]/

Changes since v3:
- Rebased on 6.5-rc6
- Dropped the useless enum names like 'JH7110_TIMER_CH_0'.
- Dropped the platform data about JH7110 and used the register offsets
directly.
- Drroped the useless functions of clk_disable_unprepare().

v3: https://lore.kernel.org/all/[email protected]/

Changes since v2:
- Rebased on 6.4-rc7.
- Merged the header file into the c file.
- Renamed the functions from 'starfive_' to 'jh7110_'
- Used function 'clocksource_register_hz' instead of
'clocksource_mmio_init'.

v2: https://lore.kernel.org/all/[email protected]/

Changes since v1:
- Added description about timer and modified properties' description
in dt-bindings.
- Dropped the 'interrupt-names' and 'clock-frequency' in dt-bindings.
- Renamed the functions and added 'starfive_'
- Modified that the driver probe by platform bus.

v1: https://lore.kernel.org/all/[email protected]/

Xingyu Wu (3):
dt-bindings: timer: Add timer for StarFive JH7110 SoC
clocksource: Add JH7110 timer driver
riscv: dts: jh7110: starfive: Add timer node

.../bindings/timer/starfive,jh7110-timer.yaml | 96 +++++
MAINTAINERS | 7 +
arch/riscv/Kconfig.socs | 1 +
arch/riscv/boot/dts/starfive/jh7110.dtsi | 20 +
drivers/clocksource/Kconfig | 9 +
drivers/clocksource/Makefile | 1 +
drivers/clocksource/timer-jh7110.c | 360 ++++++++++++++++++
include/linux/cpuhotplug.h | 1 +
8 files changed, 495 insertions(+)
create mode 100644 Documentation/devicetree/bindings/timer/starfive,jh7110-timer.yaml
create mode 100644 drivers/clocksource/timer-jh7110.c

--
2.25.1



2023-12-19 14:59:35

by Xingyu Wu

[permalink] [raw]
Subject: [PATCH v8 3/3] riscv: dts: jh7110: starfive: Add timer node

Add the timer node for the Starfive JH7110 SoC.

Reviewed-by: Emil Renner Berthing <[email protected]>
Reviewed-by: Walker Chen <[email protected]>
Signed-off-by: Xingyu Wu <[email protected]>
---
arch/riscv/boot/dts/starfive/jh7110.dtsi | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)

diff --git a/arch/riscv/boot/dts/starfive/jh7110.dtsi b/arch/riscv/boot/dts/starfive/jh7110.dtsi
index 45213cdf50dc..46836da9940f 100644
--- a/arch/riscv/boot/dts/starfive/jh7110.dtsi
+++ b/arch/riscv/boot/dts/starfive/jh7110.dtsi
@@ -904,6 +904,26 @@ sysgpio: pinctrl@13040000 {
#gpio-cells = <2>;
};

+ timer@13050000 {
+ compatible = "starfive,jh7110-timer";
+ reg = <0x0 0x13050000 0x0 0x10000>;
+ interrupts = <69>, <70>, <71>, <72>;
+ clocks = <&syscrg JH7110_SYSCLK_TIMER_APB>,
+ <&syscrg JH7110_SYSCLK_TIMER0>,
+ <&syscrg JH7110_SYSCLK_TIMER1>,
+ <&syscrg JH7110_SYSCLK_TIMER2>,
+ <&syscrg JH7110_SYSCLK_TIMER3>;
+ clock-names = "apb", "ch0", "ch1",
+ "ch2", "ch3";
+ resets = <&syscrg JH7110_SYSRST_TIMER_APB>,
+ <&syscrg JH7110_SYSRST_TIMER0>,
+ <&syscrg JH7110_SYSRST_TIMER1>,
+ <&syscrg JH7110_SYSRST_TIMER2>,
+ <&syscrg JH7110_SYSRST_TIMER3>;
+ reset-names = "apb", "ch0", "ch1",
+ "ch2", "ch3";
+ };
+
watchdog@13070000 {
compatible = "starfive,jh7110-wdt";
reg = <0x0 0x13070000 0x0 0x10000>;
--
2.25.1


2023-12-19 14:59:53

by Xingyu Wu

[permalink] [raw]
Subject: [PATCH v8 2/3] clocksource: Add JH7110 timer driver

Add timer driver for the StarFive JH7110 SoC and select it by
CONFIG_SOC_STARFIVE.

This timer has four free-running and independent 32-bit counters.
Each channel(counter) can trigger an interrupt when timeout even
CPU is sleeping. So this timer is used as global timer and register
clockevent for each CPU core after riscv-timer registration on the
StarFive JH7110 SoC.

Signed-off-by: Xingyu Wu <[email protected]>
---
MAINTAINERS | 7 +
arch/riscv/Kconfig.socs | 1 +
drivers/clocksource/Kconfig | 9 +
drivers/clocksource/Makefile | 1 +
drivers/clocksource/timer-jh7110.c | 360 +++++++++++++++++++++++++++++
include/linux/cpuhotplug.h | 1 +
6 files changed, 379 insertions(+)
create mode 100644 drivers/clocksource/timer-jh7110.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 9104430e148e..fe0e803606a5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -20617,6 +20617,13 @@ S: Maintained
F: Documentation/devicetree/bindings/sound/starfive,jh7110-tdm.yaml
F: sound/soc/starfive/jh7110_tdm.c

+STARFIVE JH7110 TIMER DRIVER
+M: Samin Guo <[email protected]>
+M: Xingyu Wu <[email protected]>
+S: Supported
+F: Documentation/devicetree/bindings/timer/starfive,jh7110-timer.yaml
+F: drivers/clocksource/timer-jh7110.c
+
STARFIVE JH71X0 CLOCK DRIVERS
M: Emil Renner Berthing <[email protected]>
M: Hal Feng <[email protected]>
diff --git a/arch/riscv/Kconfig.socs b/arch/riscv/Kconfig.socs
index e08e91c49abe..e986590f40b0 100644
--- a/arch/riscv/Kconfig.socs
+++ b/arch/riscv/Kconfig.socs
@@ -35,6 +35,7 @@ config SOC_STARFIVE
select PINCTRL
select RESET_CONTROLLER
select ARM_AMBA
+ select STARFIVE_JH7110_TIMER
help
This enables support for StarFive SoC platform hardware.

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 34faa0320ece..3f273f07a258 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -641,6 +641,15 @@ config RISCV_TIMER
is accessed via both the SBI and the rdcycle instruction. This is
required for all RISC-V systems.

+config STARFIVE_JH7110_TIMER
+ bool "Timer for the STARFIVE JH7110 SoC" if COMPILE_TEST
+ select TIMER_OF
+ select CLKSRC_MMIO
+ help
+ This enables the timer for StarFive JH7110 SoC. On RISC-V platform,
+ the system has started RISCV_TIMER, but you can also use this timer
+ which can provide four channels of higher rating on the JH7110 SoC.
+
config CLINT_TIMER
bool "CLINT Timer for the RISC-V platform" if COMPILE_TEST
depends on GENERIC_SCHED_CLOCK && RISCV
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 4bb856e4df55..8dc2f0ea2d0f 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -80,6 +80,7 @@ obj-$(CONFIG_INGENIC_TIMER) += ingenic-timer.o
obj-$(CONFIG_CLKSRC_ST_LPC) += clksrc_st_lpc.o
obj-$(CONFIG_X86_NUMACHIP) += numachip.o
obj-$(CONFIG_RISCV_TIMER) += timer-riscv.o
+obj-$(CONFIG_STARFIVE_JH7110_TIMER) += timer-jh7110.o
obj-$(CONFIG_CLINT_TIMER) += timer-clint.o
obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o
obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o
diff --git a/drivers/clocksource/timer-jh7110.c b/drivers/clocksource/timer-jh7110.c
new file mode 100644
index 000000000000..bd93e71969c2
--- /dev/null
+++ b/drivers/clocksource/timer-jh7110.c
@@ -0,0 +1,360 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Starfive JH7110 Timer driver
+ *
+ * Copyright (C) 2023 StarFive Technology Co., Ltd.
+ *
+ * This timer has four free-running and independent 32-bit counters and runs in 24MHz
+ * clock on the StarFive JH7110 SoC. Each channel(counter) can trigger an interrupt
+ * when timeout even CPU is sleeping. They support one-shot mode and continuous-run mode.
+ *
+ * Each channel is used as a global timer that serves each cpu core:
+ * JH7110 Timer Channel 0 -- CPU 0
+ * JH7110 Timer Channel 1 -- CPU 1
+ * JH7110 Timer Channel 2 -- CPU 2
+ * JH7110 Timer Channel 3 -- CPU 3
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/iopoll.h>
+#include <linux/irq.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+/* Bias: Ch0-0x0, Ch1-0x40, Ch2-0x80, and so on. */
+#define JH7110_TIMER_CH_LEN 0x40
+#define JH7110_TIMER_CH_BASE(x) ((x) * JH7110_TIMER_CH_LEN)
+#define JH7110_TIMER_CH_MAX 4
+
+#define JH7110_DELAY_US 0
+#define JH7110_TIMEOUT_US 10000
+#define JH7110_CLOCKEVENT_RATING 300
+#define JH7110_TIMER_MAX_TICKS 0xffffffff
+#define JH7110_TIMER_MIN_TICKS 0xf
+
+#define JH7110_TIMER_INT_STATUS 0x00 /*
+ * RO[0:4]: Interrupt Status for channel0~4
+ * Only valid on the JH7110_TIMER_CH_BASE(0)
+ */
+#define JH7110_TIMER_CTL 0x04 /* RW[0]: 0-continuous run, 1-single run */
+#define JH7110_TIMER_LOAD 0x08 /* RW: load value to counter */
+#define JH7110_TIMER_ENABLE 0x10 /* RW[0]: timer enable register */
+#define JH7110_TIMER_RELOAD 0x14 /* RW: write 1 or 0 both reload counter */
+#define JH7110_TIMER_VALUE 0x18 /* RO: timer value register */
+#define JH7110_TIMER_INT_CLR 0x20 /* RW: timer interrupt clear register */
+#define JH7110_TIMER_INT_MASK 0x24 /* RW[0]: timer interrupt mask register */
+
+#define JH7110_TIMER_RELOAD_VALID 0
+#define JH7110_TIMER_INT_CLR_ENA BIT(0)
+#define JH7110_TIMER_INT_CLR_AVA_MASK BIT(1)
+
+#define JH7110_PERCPU_GET_CLKEVT (&jh7110_timer_info.clkevt[smp_processor_id()])
+
+struct jh7110_clkevt {
+ struct clk *clk;
+ struct reset_control *rst;
+ void __iomem *base;
+ u32 reload_val;
+ int irq;
+ char name[sizeof("jh7110-timer.chX")];
+};
+
+struct jh7110_timer_priv {
+ struct reset_control *prst;
+ struct device *dev;
+ struct jh7110_clkevt clkevt[JH7110_TIMER_CH_MAX];
+};
+
+/* 0:continuous-run mode, 1:single-run mode */
+enum jh7110_timer_mode {
+ JH7110_TIMER_MODE_CONTIN,
+ JH7110_TIMER_MODE_SINGLE,
+};
+
+/* Interrupt Mask, 0:Unmask, 1:Mask */
+enum jh7110_timer_int_mask {
+ JH7110_TIMER_INT_ENA,
+ JH7110_TIMER_INT_DIS,
+};
+
+enum jh7110_timer_enable {
+ JH7110_TIMER_DIS,
+ JH7110_TIMER_ENA,
+};
+
+static struct jh7110_timer_priv jh7110_timer_info;
+
+/*
+ * BIT(0): Read value represent channel int status.
+ * Write 1 to this bit to clear interrupt. Write 0 has no effects.
+ * BIT(1): "1" means that it is clearing interrupt. BIT(0) can not be written.
+ */
+static int jh7110_timer_int_is_clearing(struct jh7110_clkevt *clkevt)
+{
+ u32 value;
+
+ /* Waiting interrupt can be cleared */
+ return readl_poll_timeout_atomic(clkevt->base + JH7110_TIMER_INT_CLR, value,
+ !(value & JH7110_TIMER_INT_CLR_AVA_MASK),
+ JH7110_DELAY_US, JH7110_TIMEOUT_US);
+}
+
+static int jh7110_timer_start(struct jh7110_clkevt *clkevt)
+{
+ int ret;
+
+ /* Disable and clear interrupt first */
+ writel(JH7110_TIMER_INT_DIS, clkevt->base + JH7110_TIMER_INT_MASK);
+ ret = jh7110_timer_int_is_clearing(clkevt);
+ if (ret)
+ return ret;
+
+ writel(JH7110_TIMER_INT_CLR_ENA, (clkevt->base + JH7110_TIMER_INT_CLR));
+ writel(JH7110_TIMER_INT_ENA, clkevt->base + JH7110_TIMER_INT_MASK);
+ writel(JH7110_TIMER_ENA, clkevt->base + JH7110_TIMER_ENABLE);
+
+ return 0;
+}
+
+static int jh7110_timer_shutdown(struct clock_event_device *evt)
+{
+ struct jh7110_clkevt *clkevt = JH7110_PERCPU_GET_CLKEVT;
+ int ret = 0;
+
+ writel(JH7110_TIMER_DIS, clkevt->base + JH7110_TIMER_ENABLE);
+ ret = jh7110_timer_int_is_clearing(clkevt);
+ if (!ret)
+ writel(JH7110_TIMER_INT_CLR_ENA, (clkevt->base + JH7110_TIMER_INT_CLR));
+
+ return ret;
+}
+
+static void jh7110_timer_suspend(struct clock_event_device *evt)
+{
+ struct jh7110_clkevt *clkevt = JH7110_PERCPU_GET_CLKEVT;
+
+ clkevt->reload_val = readl(clkevt->base + JH7110_TIMER_LOAD);
+ jh7110_timer_shutdown(evt);
+}
+
+static int jh7110_timer_tick_resume(struct clock_event_device *evt)
+{
+ struct jh7110_clkevt *clkevt = JH7110_PERCPU_GET_CLKEVT;
+
+ writel(clkevt->reload_val, clkevt->base + JH7110_TIMER_LOAD);
+ writel(JH7110_TIMER_RELOAD_VALID, clkevt->base + JH7110_TIMER_RELOAD);
+ return jh7110_timer_start(clkevt);
+}
+
+static void jh7110_timer_resume(struct clock_event_device *evt)
+{
+ jh7110_timer_tick_resume(evt);
+}
+
+/* IRQ handler for the timer */
+static irqreturn_t jh7110_timer_interrupt(int irq, void *data)
+{
+ struct clock_event_device *evt = data;
+ struct jh7110_clkevt *clkevt = &jh7110_timer_info.clkevt[0];
+ u8 cpu_id = smp_processor_id();
+ u32 reg = readl(clkevt->base + JH7110_TIMER_INT_STATUS);
+
+ /* Check interrupt status and channel(cpu) ID */
+ if (!(reg & BIT(cpu_id)))
+ return IRQ_NONE;
+
+ clkevt = &jh7110_timer_info.clkevt[cpu_id];
+ writel(JH7110_TIMER_INT_CLR_ENA, (clkevt->base + JH7110_TIMER_INT_CLR));
+
+ if (evt->event_handler)
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static int jh7110_timer_set_periodic(struct clock_event_device *evt)
+{
+ struct jh7110_clkevt *clkevt = JH7110_PERCPU_GET_CLKEVT;
+
+ writel(JH7110_TIMER_MODE_CONTIN, clkevt->base + JH7110_TIMER_CTL);
+ return 0;
+}
+
+static int jh7110_timer_set_oneshot(struct clock_event_device *evt)
+{
+ struct jh7110_clkevt *clkevt = JH7110_PERCPU_GET_CLKEVT;
+
+ writel(JH7110_TIMER_MODE_SINGLE, clkevt->base + JH7110_TIMER_CTL);
+ return 0;
+}
+
+static int jh7110_timer_set_next_event(unsigned long next,
+ struct clock_event_device *evt)
+{
+ struct jh7110_clkevt *clkevt = JH7110_PERCPU_GET_CLKEVT;
+
+ writel(JH7110_TIMER_MODE_SINGLE, clkevt->base + JH7110_TIMER_CTL);
+ writel(next, clkevt->base + JH7110_TIMER_LOAD);
+
+ return jh7110_timer_start(clkevt);
+}
+
+static DEFINE_PER_CPU(struct clock_event_device, jh7110_clock_event) = {
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .rating = JH7110_CLOCKEVENT_RATING,
+ .set_state_shutdown = jh7110_timer_shutdown,
+ .set_state_periodic = jh7110_timer_set_periodic,
+ .set_state_oneshot = jh7110_timer_set_oneshot,
+ .set_state_oneshot_stopped = jh7110_timer_shutdown,
+ .tick_resume = jh7110_timer_tick_resume,
+ .set_next_event = jh7110_timer_set_next_event,
+ .suspend = jh7110_timer_suspend,
+ .resume = jh7110_timer_resume,
+};
+
+static int jh7110_timer_starting_cpu(unsigned int cpu)
+{
+ struct clock_event_device *evt = per_cpu_ptr(&jh7110_clock_event, cpu);
+ struct jh7110_timer_priv *priv = &jh7110_timer_info;
+ int ret;
+ u32 rate;
+
+ if (cpu >= JH7110_TIMER_CH_MAX)
+ return -ENOMEM;
+
+ ret = clk_prepare_enable(priv->clkevt[cpu].clk);
+ if (ret)
+ return ret;
+
+ ret = reset_control_deassert(priv->clkevt[cpu].rst);
+ if (ret)
+ return ret;
+
+ rate = clk_get_rate(priv->clkevt[cpu].clk);
+ evt->cpumask = cpumask_of(cpu);
+ evt->irq = priv->clkevt[cpu].irq;
+ evt->name = priv->clkevt[cpu].name;
+ clockevents_config_and_register(evt, rate, JH7110_TIMER_MIN_TICKS,
+ JH7110_TIMER_MAX_TICKS);
+
+ ret = devm_request_irq(priv->dev, evt->irq, jh7110_timer_interrupt,
+ IRQF_TIMER | IRQF_IRQPOLL,
+ evt->name, evt);
+ if (ret)
+ return ret;
+
+ ret = irq_set_affinity(evt->irq, cpumask_of(cpu));
+ if (ret)
+ return ret;
+
+ /* Use one-shot mode */
+ writel(JH7110_TIMER_MODE_SINGLE, (priv->clkevt[cpu].base + JH7110_TIMER_CTL));
+
+ return jh7110_timer_start(&priv->clkevt[cpu]);
+}
+
+static void jh7110_timer_release(void *data)
+{
+ struct jh7110_timer_priv *priv = data;
+ int i;
+
+ for (i = 0; i < JH7110_TIMER_CH_MAX; i++) {
+ /* Disable each channel of timer */
+ if (priv->clkevt[i].base)
+ writel(JH7110_TIMER_DIS, priv->clkevt[i].base + JH7110_TIMER_ENABLE);
+
+ /* Avoid no initialization in the loop of the probe */
+ if (!IS_ERR_OR_NULL(priv->clkevt[i].rst))
+ reset_control_assert(priv->clkevt[i].rst);
+
+ if (!IS_ERR_OR_NULL(priv->clkevt[i].clk))
+ clk_disable_unprepare(priv->clkevt[i].clk);
+ }
+
+ reset_control_assert(priv->prst);
+}
+
+static int jh7110_timer_probe(struct platform_device *pdev)
+{
+ struct jh7110_timer_priv *priv = &jh7110_timer_info;
+ struct jh7110_clkevt *clkevt;
+ struct clk *pclk;
+ void __iomem *base;
+ int ch;
+ int ret;
+ char name[sizeof("chX")];
+
+ base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(base))
+ return dev_err_probe(&pdev->dev, PTR_ERR(base),
+ "failed to map registers\n");
+
+ priv->prst = devm_reset_control_get_exclusive(&pdev->dev, "apb");
+ if (IS_ERR(priv->prst))
+ return dev_err_probe(&pdev->dev, PTR_ERR(priv->prst),
+ "failed to get apb reset\n");
+
+ pclk = devm_clk_get_enabled(&pdev->dev, "apb");
+ if (IS_ERR(pclk))
+ return dev_err_probe(&pdev->dev, PTR_ERR(pclk),
+ "failed to get & enable apb clock\n");
+
+ ret = reset_control_deassert(priv->prst);
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret, "failed to deassert apb reset\n");
+
+ ret = devm_add_action_or_reset(&pdev->dev, jh7110_timer_release, priv);
+ if (ret)
+ return ret;
+
+ priv->dev = &pdev->dev;
+ for (ch = 0; ch < JH7110_TIMER_CH_MAX; ch++) {
+ clkevt = &priv->clkevt[ch];
+ snprintf(name, sizeof(name), "ch%d", ch);
+
+ clkevt->base = base + JH7110_TIMER_CH_BASE(ch);
+ /* Ensure timer is disabled */
+ writel(JH7110_TIMER_DIS, clkevt->base + JH7110_TIMER_ENABLE);
+ if (!jh7110_timer_int_is_clearing(clkevt))
+ writel(JH7110_TIMER_INT_CLR_ENA, (clkevt->base + JH7110_TIMER_INT_CLR));
+
+ clkevt->rst = devm_reset_control_get_exclusive(&pdev->dev, name);
+ if (IS_ERR(clkevt->rst))
+ return PTR_ERR(clkevt->rst);
+
+ clkevt->clk = devm_clk_get(&pdev->dev, name);
+ if (IS_ERR(clkevt->clk))
+ return PTR_ERR(clkevt->clk);
+
+ clkevt->irq = platform_get_irq(pdev, ch);
+ if (clkevt->irq < 0)
+ return clkevt->irq;
+
+ snprintf(clkevt->name, sizeof(clkevt->name), "jh7110-timer.ch%d", ch);
+ }
+
+ return cpuhp_setup_state(CPUHP_AP_JH7110_TIMER_STARTING,
+ "clockevents/jh7110/timer:starting",
+ jh7110_timer_starting_cpu, NULL);
+}
+
+static const struct of_device_id jh7110_timer_match[] = {
+ { .compatible = "starfive,jh7110-timer", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, jh7110_timer_match);
+
+static struct platform_driver jh7110_timer_driver = {
+ .probe = jh7110_timer_probe,
+ .driver = {
+ .name = "jh7110-timer",
+ .of_match_table = jh7110_timer_match,
+ },
+};
+module_platform_driver(jh7110_timer_driver);
+
+MODULE_AUTHOR("Xingyu Wu <[email protected]>");
+MODULE_DESCRIPTION("StarFive JH7110 timer driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index efc0c0b07efb..f28a3aaf93f9 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -187,6 +187,7 @@ enum cpuhp_state {
CPUHP_AP_CSKY_TIMER_STARTING,
CPUHP_AP_TI_GP_TIMER_STARTING,
CPUHP_AP_HYPERV_TIMER_STARTING,
+ CPUHP_AP_JH7110_TIMER_STARTING,
/* Must be the last timer callback */
CPUHP_AP_DUMMY_TIMER_STARTING,
CPUHP_AP_ARM_XEN_STARTING,
--
2.25.1


2023-12-20 14:00:47

by Emil Renner Berthing

[permalink] [raw]
Subject: Re: [PATCH v8 2/3] clocksource: Add JH7110 timer driver

Xingyu Wu wrote:
> Add timer driver for the StarFive JH7110 SoC and select it by
> CONFIG_SOC_STARFIVE.
>
> This timer has four free-running and independent 32-bit counters.
> Each channel(counter) can trigger an interrupt when timeout even
> CPU is sleeping. So this timer is used as global timer and register
> clockevent for each CPU core after riscv-timer registration on the
> StarFive JH7110 SoC.
>
> Signed-off-by: Xingyu Wu <[email protected]>
> ---
> MAINTAINERS | 7 +
> arch/riscv/Kconfig.socs | 1 +
> drivers/clocksource/Kconfig | 9 +
> drivers/clocksource/Makefile | 1 +
> drivers/clocksource/timer-jh7110.c | 360 +++++++++++++++++++++++++++++
> include/linux/cpuhotplug.h | 1 +
> 6 files changed, 379 insertions(+)
> create mode 100644 drivers/clocksource/timer-jh7110.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 9104430e148e..fe0e803606a5 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -20617,6 +20617,13 @@ S: Maintained
> F: Documentation/devicetree/bindings/sound/starfive,jh7110-tdm.yaml
> F: sound/soc/starfive/jh7110_tdm.c
>
> +STARFIVE JH7110 TIMER DRIVER
> +M: Samin Guo <[email protected]>

Last time I sent a mail to [email protected] it bounced. Was that just
a temporary error?

/Emil

> +M: Xingyu Wu <[email protected]>
> +S: Supported
> +F: Documentation/devicetree/bindings/timer/starfive,jh7110-timer.yaml
> +F: drivers/clocksource/timer-jh7110.c
> +
> STARFIVE JH71X0 CLOCK DRIVERS
> M: Emil Renner Berthing <[email protected]>
> M: Hal Feng <[email protected]>

2023-12-21 01:58:46

by Xingyu Wu

[permalink] [raw]
Subject: Re: [PATCH v8 2/3] clocksource: Add JH7110 timer driver

On 2023/12/20 21:59, Emil Renner Berthing wrote:
> Xingyu Wu wrote:
>> Add timer driver for the StarFive JH7110 SoC and select it by
>> CONFIG_SOC_STARFIVE.
>>
>> This timer has four free-running and independent 32-bit counters.
>> Each channel(counter) can trigger an interrupt when timeout even
>> CPU is sleeping. So this timer is used as global timer and register
>> clockevent for each CPU core after riscv-timer registration on the
>> StarFive JH7110 SoC.
>>
>> Signed-off-by: Xingyu Wu <[email protected]>
>> ---
>> MAINTAINERS | 7 +
>> arch/riscv/Kconfig.socs | 1 +
>> drivers/clocksource/Kconfig | 9 +
>> drivers/clocksource/Makefile | 1 +
>> drivers/clocksource/timer-jh7110.c | 360 +++++++++++++++++++++++++++++
>> include/linux/cpuhotplug.h | 1 +
>> 6 files changed, 379 insertions(+)
>> create mode 100644 drivers/clocksource/timer-jh7110.c
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index 9104430e148e..fe0e803606a5 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -20617,6 +20617,13 @@ S: Maintained
>> F: Documentation/devicetree/bindings/sound/starfive,jh7110-tdm.yaml
>> F: sound/soc/starfive/jh7110_tdm.c
>>
>> +STARFIVE JH7110 TIMER DRIVER
>> +M: Samin Guo <[email protected]>
>
> Last time I sent a mail to [email protected] it bounced. Was that just
> a temporary error?
>
> /Emil

Oh, This email has been deactivated and I don't have his other personal email.
I had dropped it in the driver but forget it here.
Will fix.

Thanks,
Xingyu Wu

>
>> +M: Xingyu Wu <[email protected]>
>> +S: Supported
>> +F: Documentation/devicetree/bindings/timer/starfive,jh7110-timer.yaml
>> +F: drivers/clocksource/timer-jh7110.c
>> +
>> STARFIVE JH71X0 CLOCK DRIVERS
>> M: Emil Renner Berthing <[email protected]>
>> M: Hal Feng <[email protected]>


2024-02-27 01:27:12

by Xingyu Wu

[permalink] [raw]
Subject: 回复: [PATCH v8 0/3] Add timer driver for Sta rFive JH7110 RISC-V SoC

Hi Daniel,

Could you please help to review this patch and give your comments if you have time?
Thanks.

Best regards,
Xingyu Wu

-----?ʼ?ԭ??-----
??????: Xingyu Wu <[email protected]>
????ʱ??: 2023??12??19?? 22:54
?ռ???: Daniel Lezcano <[email protected]>; Thomas Gleixner <[email protected]>; Emil Renner Berthing <[email protected]>; Christophe JAILLET <[email protected]>
????: [email protected]; [email protected]; Rob Herring <[email protected]>; Krzysztof Kozlowski <[email protected]>; Paul Walmsley <[email protected]>; Palmer Dabbelt <[email protected]>; Albert Ou <[email protected]>; Philipp Zabel <[email protected]>; Walker Chen <[email protected]>; Xingyu Wu <[email protected]>; [email protected]; Conor Dooley <[email protected]>
????: [PATCH v8 0/3] Add timer driver for StarFive JH7110 RISC-V SoC

This patch serises are to add timer driver for the StarFive JH7110 RISC-V SoC. The first patch adds documentation to describe device tree bindings. The subsequent patch adds timer driver and support
JH7110 SoC. The last patch adds device node about timer in JH7110 dts.

This timer has four free-running 32 bit counters and runs in 24MHz clock on StarFive JH7110 SoC. And each channel(counter) triggers an interrupt when timeout. They support one-shot mode and continuous-run mode.

This timer is used as global timer and register clockevent for each CPU core after riscv-timer registration on the StarFive JH7110 SoC.

Changes since v7:
- Rebased on 6.7-rc6.
- Modified the Kconfig file and added selection in SOC_STARFIVE.
- Used the timer as a global timer and registered as clockevent
for each CPU core.
- Dropped the timeout function in the interrupt handler callback.
- Changed the way in the functions of jh7110_timer_tick_resume() and
jh7110_timer_resume().
- Dropped the registration of clocksource in the probe.

v7: https://lore.kernel.org/all/[email protected]/

Changes since v6:
- Rebased on 6.6-rc6.
- Used sizeof() instead of the numbers of characters about names.
- Added devm_add_action_or_reset() to release the resets and
clocksources in the case of remove or error in the probe.
- Added flags to check each clocksource is suceessfully registered and
used in the release function.
- Dropped the variable of irq in the jh7110_clkevt struct.
- Dropped the wrappers and used enum definitions and writel() calls
directly.

v6: https://lore.kernel.org/all/[email protected]/

Changes since v5:
- Rebased on 6.6-rc5.
- Changed the number about characters of name.
- Made the clkevt->periodic to a local variable.
- Dropped the variables of device and base.
- Used clkevt->evt.irq directly and dropped the extra copy of irq.

V5: https://lore.kernel.org/all/[email protected]/

Changes since v4:
- Rebased on 6.5.
- Dropped the useless enum and used value directly when writing
registers.
- Modified the description in Kconfig.
- Add the reviewed tag in patch 3.

v4: https://lore.kernel.org/all/[email protected]/

Changes since v3:
- Rebased on 6.5-rc6
- Dropped the useless enum names like 'JH7110_TIMER_CH_0'.
- Dropped the platform data about JH7110 and used the register offsets
directly.
- Drroped the useless functions of clk_disable_unprepare().

v3: https://lore.kernel.org/all/[email protected]/

Changes since v2:
- Rebased on 6.4-rc7.
- Merged the header file into the c file.
- Renamed the functions from 'starfive_' to 'jh7110_'
- Used function 'clocksource_register_hz' instead of
'clocksource_mmio_init'.

v2: https://lore.kernel.org/all/[email protected]/

Changes since v1:
- Added description about timer and modified properties' description
in dt-bindings.
- Dropped the 'interrupt-names' and 'clock-frequency' in dt-bindings.
- Renamed the functions and added 'starfive_'
- Modified that the driver probe by platform bus.

v1: https://lore.kernel.org/all/[email protected]/

Xingyu Wu (3):
dt-bindings: timer: Add timer for StarFive JH7110 SoC
clocksource: Add JH7110 timer driver
riscv: dts: jh7110: starfive: Add timer node

.../bindings/timer/starfive,jh7110-timer.yaml | 96 +++++
MAINTAINERS | 7 +
arch/riscv/Kconfig.socs | 1 +
arch/riscv/boot/dts/starfive/jh7110.dtsi | 20 +
drivers/clocksource/Kconfig | 9 +
drivers/clocksource/Makefile | 1 +
drivers/clocksource/timer-jh7110.c | 360 ++++++++++++++++++
include/linux/cpuhotplug.h | 1 +
8 files changed, 495 insertions(+)
create mode 100644 Documentation/devicetree/bindings/timer/starfive,jh7110-timer.yaml
create mode 100644 drivers/clocksource/timer-jh7110.c

--
2.25.1

2024-02-27 16:33:09

by Thomas Gleixner

[permalink] [raw]
Subject: Re: [PATCH v8 2/3] clocksource: Add JH7110 timer driver

On Tue, Dec 19 2023 at 22:54, Xingyu Wu wrote:
> +
> +struct jh7110_clkevt {
> + struct clk *clk;
> + struct reset_control *rst;
> + void __iomem *base;
> + u32 reload_val;
> + int irq;
> + char name[sizeof("jh7110-timer.chX")];
> +};
> +
> +struct jh7110_timer_priv {
> + struct reset_control *prst;
> + struct device *dev;
> + struct jh7110_clkevt clkevt[JH7110_TIMER_CH_MAX];
> +};

Please format your data structures according to documentation:

https://www.kernel.org/doc/html/latest/process/maintainer-tip.html#struct-declarations-and-initializers

> +/* IRQ handler for the timer */
> +static irqreturn_t jh7110_timer_interrupt(int irq, void *data)
> +{
> + struct clock_event_device *evt = data;
> + struct jh7110_clkevt *clkevt = &jh7110_timer_info.clkevt[0];
> + u8 cpu_id = smp_processor_id();
> + u32 reg = readl(clkevt->base + JH7110_TIMER_INT_STATUS);

https://www.kernel.org/doc/html/latest/process/maintainer-tip.html#variable-declarations

> + /* Check interrupt status and channel(cpu) ID */
> + if (!(reg & BIT(cpu_id)))
> + return IRQ_NONE;
> +
> + clkevt = &jh7110_timer_info.clkevt[cpu_id];
> + writel(JH7110_TIMER_INT_CLR_ENA, (clkevt->base + JH7110_TIMER_INT_CLR));
> +
> + if (evt->event_handler)
> + evt->event_handler(evt);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int jh7110_timer_set_periodic(struct clock_event_device *evt)
> +{
> + struct jh7110_clkevt *clkevt = JH7110_PERCPU_GET_CLKEVT;
> +
> + writel(JH7110_TIMER_MODE_CONTIN, clkevt->base + JH7110_TIMER_CTL);
> + return 0;
> +}
> +
> +static int jh7110_timer_set_oneshot(struct clock_event_device *evt)
> +{
> + struct jh7110_clkevt *clkevt = JH7110_PERCPU_GET_CLKEVT;
> +
> + writel(JH7110_TIMER_MODE_SINGLE, clkevt->base + JH7110_TIMER_CTL);
> + return 0;
> +}
> +
> +static int jh7110_timer_set_next_event(unsigned long next,
> + struct clock_event_device *evt)
> +{
> + struct jh7110_clkevt *clkevt = JH7110_PERCPU_GET_CLKEVT;
> +
> + writel(JH7110_TIMER_MODE_SINGLE, clkevt->base + JH7110_TIMER_CTL);
> + writel(next, clkevt->base + JH7110_TIMER_LOAD);
> +
> + return jh7110_timer_start(clkevt);
> +}
> +
> +static DEFINE_PER_CPU(struct clock_event_device, jh7110_clock_event) = {
> + .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
> + .rating = JH7110_CLOCKEVENT_RATING,
> + .set_state_shutdown = jh7110_timer_shutdown,
> + .set_state_periodic = jh7110_timer_set_periodic,
> + .set_state_oneshot = jh7110_timer_set_oneshot,
> + .set_state_oneshot_stopped = jh7110_timer_shutdown,
> + .tick_resume = jh7110_timer_tick_resume,
> + .set_next_event = jh7110_timer_set_next_event,
> + .suspend = jh7110_timer_suspend,
> + .resume = jh7110_timer_resume,
> +};

See formatting rules.

> +static int jh7110_timer_starting_cpu(unsigned int cpu)
> +{
> + struct clock_event_device *evt = per_cpu_ptr(&jh7110_clock_event, cpu);
> + struct jh7110_timer_priv *priv = &jh7110_timer_info;
> + int ret;
> + u32 rate;
> +
> + if (cpu >= JH7110_TIMER_CH_MAX)
> + return -ENOMEM;
> +
> + ret = clk_prepare_enable(priv->clkevt[cpu].clk);
> + if (ret)
> + return ret;
> +
> + ret = reset_control_deassert(priv->clkevt[cpu].rst);
> + if (ret)
> + return ret;
> +
> + rate = clk_get_rate(priv->clkevt[cpu].clk);
> + evt->cpumask = cpumask_of(cpu);
> + evt->irq = priv->clkevt[cpu].irq;
> + evt->name = priv->clkevt[cpu].name;
> + clockevents_config_and_register(evt, rate, JH7110_TIMER_MIN_TICKS,
> + JH7110_TIMER_MAX_TICKS);
> +
> + ret = devm_request_irq(priv->dev, evt->irq, jh7110_timer_interrupt,
> + IRQF_TIMER | IRQF_IRQPOLL,
> + evt->name, evt);

How is this all supposed to work from a CPU hotplug state callback which
runs in the early bringup phase with interrupts disabled? clk_prepare()
which is invoked from clk_prepare_enable() can sleep and
devm_request_irq() can sleep too.

Did you ever test this with the required debug config options enabled?

https://www.kernel.org/doc/html/latest/process/submit-checklist.html

Obviously not.

> + if (ret)
> + return ret;
> +
> + ret = irq_set_affinity(evt->irq, cpumask_of(cpu));
> + if (ret)
> + return ret;
> + /* Use one-shot mode */
> + writel(JH7110_TIMER_MODE_SINGLE, (priv->clkevt[cpu].base + JH7110_TIMER_CTL));
> +
> + return jh7110_timer_start(&priv->clkevt[cpu]);
> +}
> +
> +static void jh7110_timer_release(void *data)
> +{
> + struct jh7110_timer_priv *priv = data;
> + int i;
> +
> + for (i = 0; i < JH7110_TIMER_CH_MAX; i++) {
> + /* Disable each channel of timer */
> + if (priv->clkevt[i].base)
> + writel(JH7110_TIMER_DIS, priv->clkevt[i].base + JH7110_TIMER_ENABLE);
> +
> + /* Avoid no initialization in the loop of the probe */
> + if (!IS_ERR_OR_NULL(priv->clkevt[i].rst))
> + reset_control_assert(priv->clkevt[i].rst);
> +
> + if (!IS_ERR_OR_NULL(priv->clkevt[i].clk))
> + clk_disable_unprepare(priv->clkevt[i].clk);

Same problem. And of course this does not undo the other steps of
jh7110_timer_starting_cpu() so if you offline a CPU and then online it
again the callback will fail because the clockevent is already
registered and the interrupt requested. Clearly untested too.

Thanks,

tglx