[PATCH 1/2] dt-bindings: clocksource: Add Spreadtrum SC9860 timer

[PATCH 1/2] dt-bindings: clocksource: Add Spreadtrum SC9860 timer

[Baolin Wang]

This patch adds documentation of device tree bindings for the timers
found on Spreadtrum SC9860 platform.

Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com>
---
 .../bindings/timer/spreadtrum,sprd-timer.txt       |   20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/timer/spreadtrum,sprd-timer.txt

diff --git a/Documentation/devicetree/bindings/timer/spreadtrum,sprd-timer.txt b/Documentation/devicetree/bindings/timer/spreadtrum,sprd-timer.txt
new file mode 100644
index 0000000..f9d5eb9
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/spreadtrum,sprd-timer.txt
@@ -0,0 +1,20 @@
+Spreadtrum timers
+
+The Spreadtrum SC9860 platform provides 3 general-purpose timers.
+These timers can support 32bit or 64bit counter, as well as supporting
+period mode or one-shot mode, and they are can be wakeup source
+during deep sleep.
+
+Required properties:
+- compatible: should be "sprd,sc9860-timer" for SC9860 platform.
+- reg: The register address of the timer device.
+- interrupts: Should contain the interrupt for the timer device.
+- clock-frequency: The frequency of the clock that drives the counter, in Hz.
+
+Example:
+	timer@40050000 {
+		compatible = "sprd,sc9860-timer";
+		reg = <0 0x40050000 0 0x20>;
+		interrupts = <GIC_SPI 26 IRQ_TYPE_LEVEL_HIGH>;
+		clock-frequency = <32768>;
+	};
-- 
1.7.9.5

[PATCH 2/2] clocksource: sprd: Add timer driver for Spreadtrum SC9860 platform

[Baolin Wang]

The Spreadtrum SC9860 platform will use the architected timers as local
clock events, but we also need a broadcast timer device to wakeup the
cpus when the cpus are in sleep mode.

Thus this patch registers the timer0 to be a broadcast timer supporting
periodic and oneshot events.

Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com>
---
 drivers/clocksource/Kconfig      |    8 ++
 drivers/clocksource/Makefile     |    1 +
 drivers/clocksource/sprd-timer.c |  213 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 222 insertions(+)
 create mode 100644 drivers/clocksource/sprd-timer.c

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index cc60620..aa05132 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -467,6 +467,14 @@ config MTK_TIMER
 	help
 	  Support for Mediatek timer driver.
 
+config SPRD_TIMER
+	bool "Spreadtrum timer driver"
+	depends on GENERIC_CLOCKEVENTS
+	depends on ARCH_SPRD || COMPILE_TEST
+	select TIMER_OF
+	help
+	  Enables the support for the Spreadtrum timer driver.
+
 config SYS_SUPPORTS_SH_MTU2
         bool
 
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index dbc1ad1..c657d3d 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -53,6 +53,7 @@ obj-$(CONFIG_CLKSRC_TI_32K)	+= timer-ti-32k.o
 obj-$(CONFIG_CLKSRC_NPS)	+= timer-nps.o
 obj-$(CONFIG_OXNAS_RPS_TIMER)	+= timer-oxnas-rps.o
 obj-$(CONFIG_OWL_TIMER)		+= owl-timer.o
+obj-$(CONFIG_SPRD_TIMER)	+= sprd-timer.o
 
 obj-$(CONFIG_ARC_TIMERS)		+= arc_timer.o
 obj-$(CONFIG_ARM_ARCH_TIMER)		+= arm_arch_timer.o
diff --git a/drivers/clocksource/sprd-timer.c b/drivers/clocksource/sprd-timer.c
new file mode 100644
index 0000000..6fec0c5
--- /dev/null
+++ b/drivers/clocksource/sprd-timer.c
@@ -0,0 +1,213 @@
+/*
+ * Copyright (C) 2017 Spreadtrum Communications Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define TIMER_NAME		"sprd_timer"
+
+#define TIMER_LOAD_LO		0x0
+#define TIMER_LOAD_HI		0x4
+#define TIMER_VALUE_LO		0x8
+#define TIMER_VALUE_HI		0xc
+
+#define TIMER_CTL		0x10
+#define TIMER_CTL_PERIOD_MODE	BIT(0)
+#define TIMER_CTL_ENABLE	BIT(1)
+#define TIMER_CTL_64BIT_WIDTH	BIT(16)
+
+#define TIMER_INT		0x14
+#define TIMER_INT_EN		BIT(0)
+#define TIMER_INT_RAW_STS	BIT(1)
+#define TIMER_INT_MASK_STS	BIT(2)
+#define TIMER_INT_CLR		BIT(3)
+
+#define TIMER_VALUE_SHDW_LO	0x18
+#define TIMER_VALUE_SHDW_HI	0x1c
+
+#define TIMER_VALUE_LO_MASK	GENMASK(31, 0)
+#define TIMER_VALUE_HI_SHIFT	32
+
+struct sprd_timer_device {
+	struct clock_event_device ce;
+	void __iomem *base;
+	u32 freq;
+	int irq;
+};
+
+static inline struct sprd_timer_device *
+to_sprd_timer(struct clock_event_device *c)
+{
+	return container_of(c, struct sprd_timer_device, ce);
+}
+
+static void sprd_timer_enable(struct sprd_timer_device *timer, u32 flag)
+{
+	u32 val = readl_relaxed(timer->base + TIMER_CTL);
+
+	val |= TIMER_CTL_ENABLE;
+	if (flag & TIMER_CTL_64BIT_WIDTH)
+		val |= TIMER_CTL_64BIT_WIDTH;
+	else
+		val &= ~TIMER_CTL_64BIT_WIDTH;
+
+	if (flag & TIMER_CTL_PERIOD_MODE)
+		val |= TIMER_CTL_PERIOD_MODE;
+	else
+		val &= ~TIMER_CTL_PERIOD_MODE;
+
+	writel_relaxed(val, timer->base + TIMER_CTL);
+}
+
+static void sprd_timer_disable(struct sprd_timer_device *timer)
+{
+	u32 val = readl_relaxed(timer->base + TIMER_CTL);
+
+	val &= ~TIMER_CTL_ENABLE;
+	writel_relaxed(val, timer->base + TIMER_CTL);
+}
+
+static void sprd_timer_update_counter(struct sprd_timer_device *timer,
+				      unsigned long cycles)
+{
+	writel_relaxed(cycles & TIMER_VALUE_LO_MASK,
+		       timer->base + TIMER_LOAD_LO);
+	writel_relaxed(cycles >> TIMER_VALUE_HI_SHIFT,
+		       timer->base + TIMER_LOAD_HI);
+}
+
+static void sprd_timer_enable_interrupt(struct sprd_timer_device *timer)
+{
+	writel_relaxed(TIMER_INT_EN, timer->base + TIMER_INT);
+}
+
+static void sprd_timer_clear_interrupt(struct sprd_timer_device *timer)
+{
+	u32 val = readl_relaxed(timer->base + TIMER_INT);
+
+	val |= TIMER_INT_CLR;
+	writel_relaxed(val, timer->base + TIMER_INT);
+}
+
+static int sprd_timer_set_next_event(unsigned long cycles,
+				     struct clock_event_device *ce)
+{
+	struct sprd_timer_device *timer = to_sprd_timer(ce);
+
+	sprd_timer_disable(timer);
+	sprd_timer_update_counter(timer, cycles);
+	sprd_timer_enable(timer, TIMER_CTL_64BIT_WIDTH);
+
+	return 0;
+}
+
+static int sprd_timer_set_periodic(struct clock_event_device *ce)
+{
+	struct sprd_timer_device *timer = to_sprd_timer(ce);
+	unsigned long cycles = DIV_ROUND_UP(timer->freq, HZ);
+
+	sprd_timer_disable(timer);
+	sprd_timer_update_counter(timer, cycles);
+	sprd_timer_enable(timer, TIMER_CTL_64BIT_WIDTH | TIMER_CTL_PERIOD_MODE);
+
+	return 0;
+}
+
+static int sprd_timer_shutdown(struct clock_event_device *ce)
+{
+	struct sprd_timer_device *timer = to_sprd_timer(ce);
+
+	sprd_timer_disable(timer);
+	return 0;
+}
+
+static irqreturn_t sprd_timer_interrupt(int irq, void *dev_id)
+{
+	struct sprd_timer_device *timer = dev_id;
+
+	sprd_timer_clear_interrupt(timer);
+
+	if (clockevent_state_oneshot(&timer->ce))
+		sprd_timer_disable(timer);
+
+	timer->ce.event_handler(&timer->ce);
+	return IRQ_HANDLED;
+}
+
+static void __init sprd_timer_clkevt_init(struct sprd_timer_device *timer)
+{
+	timer->ce.features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_PERIODIC |
+				CLOCK_EVT_FEAT_ONESHOT;
+	timer->ce.set_next_event = sprd_timer_set_next_event;
+	timer->ce.set_state_periodic = sprd_timer_set_periodic;
+	timer->ce.set_state_shutdown = sprd_timer_shutdown;
+	timer->ce.name = TIMER_NAME;
+	timer->ce.rating = 300;
+	timer->ce.irq = timer->irq;
+	timer->ce.cpumask = cpu_possible_mask;
+
+	sprd_timer_enable_interrupt(timer);
+	clockevents_config_and_register(&timer->ce, timer->freq, 1, UINT_MAX);
+}
+
+static int __init sprd_timer_init(struct device_node *np)
+{
+	struct sprd_timer_device *timer;
+	int ret;
+
+	timer = kzalloc(sizeof(*timer), GFP_KERNEL);
+	if (!timer)
+		return -ENOMEM;
+
+	ret = of_property_read_u32(np, "clock-frequency", &timer->freq);
+	if (ret) {
+		pr_err("failed to get clock frequency\n");
+		goto err_freq;
+	}
+
+	timer->base = of_iomap(np, 0);
+	if (!timer->base) {
+		pr_err("%s: unable to map resource\n", np->name);
+		ret = -ENXIO;
+		goto err_freq;
+	}
+
+	timer->irq = irq_of_parse_and_map(np, 0);
+	if (timer->irq < 0) {
+		pr_crit("%s: unable to parse timer irq\n", np->name);
+		ret = timer->irq;
+		goto err_map_irq;
+	}
+
+	ret = request_irq(timer->irq, sprd_timer_interrupt, IRQF_TIMER,
+			  TIMER_NAME, timer);
+	if (ret) {
+		pr_err("failed to setup irq %d\n", timer->irq);
+		goto err_request_irq;
+	}
+
+	sprd_timer_clkevt_init(timer);
+
+	return 0;
+
+err_request_irq:
+	irq_dispose_mapping(timer->irq);
+err_map_irq:
+	iounmap(timer->base);
+err_freq:
+	kfree(timer);
+
+	return ret;
+}
+
+TIMER_OF_DECLARE(sc9860_timer, "sprd,sc9860-timer", sprd_timer_init);
-- 
1.7.9.5

Re: [PATCH 2/2] clocksource: sprd: Add timer driver for Spreadtrum SC9860 platform

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 4617 bytes --]

Hi Baolin,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on tip/timers/core]
[also build test WARNING on v4.14 next-20171124]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Baolin-Wang/dt-bindings-clocksource-Add-Spreadtrum-SC9860-timer/20171125-090749
config: i386-allmodconfig (attached as .config)
compiler: gcc-6 (Debian 6.4.0-9) 6.4.0 20171026
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All warnings (new ones prefixed by >>):

   In file included from arch/x86/include/asm/realmode.h:14:0,
                    from arch/x86/include/asm/acpi.h:33,
                    from arch/x86/include/asm/fixmap.h:19,
                    from arch/x86/include/asm/apic.h:10,
                    from arch/x86/include/asm/smp.h:12,
                    from include/linux/smp.h:63,
                    from include/linux/topology.h:33,
                    from include/linux/gfp.h:8,
                    from include/linux/idr.h:16,
                    from include/linux/kernfs.h:14,
                    from include/linux/sysfs.h:15,
                    from include/linux/kobject.h:21,
                    from include/linux/of.h:21,
                    from include/linux/clocksource.h:18,
                    from drivers/clocksource/sprd-timer.c:7:
   drivers/clocksource/sprd-timer.c: In function 'sprd_timer_update_counter':
>> drivers/clocksource/sprd-timer.c:85:24: warning: right shift count >= width of type [-Wshift-count-overflow]
     writel_relaxed(cycles >> TIMER_VALUE_HI_SHIFT,
                           ^
   arch/x86/include/asm/io.h:87:39: note: in definition of macro 'writel_relaxed'
    #define writel_relaxed(v, a) __writel(v, a)
                                          ^

vim +85 drivers/clocksource/sprd-timer.c

   > 7	#include <linux/clocksource.h>
     8	#include <linux/clockchips.h>
     9	#include <linux/init.h>
    10	#include <linux/interrupt.h>
    11	#include <linux/sched_clock.h>
    12	#include <linux/slab.h>
    13	#include <linux/of.h>
    14	#include <linux/of_address.h>
    15	#include <linux/of_irq.h>
    16	
    17	#define TIMER_NAME		"sprd_timer"
    18	
    19	#define TIMER_LOAD_LO		0x0
    20	#define TIMER_LOAD_HI		0x4
    21	#define TIMER_VALUE_LO		0x8
    22	#define TIMER_VALUE_HI		0xc
    23	
    24	#define TIMER_CTL		0x10
    25	#define TIMER_CTL_PERIOD_MODE	BIT(0)
    26	#define TIMER_CTL_ENABLE	BIT(1)
    27	#define TIMER_CTL_64BIT_WIDTH	BIT(16)
    28	
    29	#define TIMER_INT		0x14
    30	#define TIMER_INT_EN		BIT(0)
    31	#define TIMER_INT_RAW_STS	BIT(1)
    32	#define TIMER_INT_MASK_STS	BIT(2)
    33	#define TIMER_INT_CLR		BIT(3)
    34	
    35	#define TIMER_VALUE_SHDW_LO	0x18
    36	#define TIMER_VALUE_SHDW_HI	0x1c
    37	
    38	#define TIMER_VALUE_LO_MASK	GENMASK(31, 0)
    39	#define TIMER_VALUE_HI_SHIFT	32
    40	
    41	struct sprd_timer_device {
    42		struct clock_event_device ce;
    43		void __iomem *base;
    44		u32 freq;
    45		int irq;
    46	};
    47	
    48	static inline struct sprd_timer_device *
    49	to_sprd_timer(struct clock_event_device *c)
    50	{
    51		return container_of(c, struct sprd_timer_device, ce);
    52	}
    53	
    54	static void sprd_timer_enable(struct sprd_timer_device *timer, u32 flag)
    55	{
    56		u32 val = readl_relaxed(timer->base + TIMER_CTL);
    57	
    58		val |= TIMER_CTL_ENABLE;
    59		if (flag & TIMER_CTL_64BIT_WIDTH)
    60			val |= TIMER_CTL_64BIT_WIDTH;
    61		else
    62			val &= ~TIMER_CTL_64BIT_WIDTH;
    63	
    64		if (flag & TIMER_CTL_PERIOD_MODE)
    65			val |= TIMER_CTL_PERIOD_MODE;
    66		else
    67			val &= ~TIMER_CTL_PERIOD_MODE;
    68	
    69		writel_relaxed(val, timer->base + TIMER_CTL);
    70	}
    71	
    72	static void sprd_timer_disable(struct sprd_timer_device *timer)
    73	{
    74		u32 val = readl_relaxed(timer->base + TIMER_CTL);
    75	
    76		val &= ~TIMER_CTL_ENABLE;
    77		writel_relaxed(val, timer->base + TIMER_CTL);
    78	}
    79	
    80	static void sprd_timer_update_counter(struct sprd_timer_device *timer,
    81					      unsigned long cycles)
    82	{
    83		writel_relaxed(cycles & TIMER_VALUE_LO_MASK,
    84			       timer->base + TIMER_LOAD_LO);
  > 85		writel_relaxed(cycles >> TIMER_VALUE_HI_SHIFT,
    86			       timer->base + TIMER_LOAD_HI);
    87	}
    88	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 61854 bytes --]

Re: [PATCH 2/2] clocksource: sprd: Add timer driver for Spreadtrum SC9860 platform

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 3096 bytes --]

Hi Baolin,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on tip/timers/core]
[also build test WARNING on v4.14 next-20171124]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Baolin-Wang/dt-bindings-clocksource-Add-Spreadtrum-SC9860-timer/20171125-090749
config: arm-allmodconfig (attached as .config)
compiler: arm-linux-gnueabi-gcc (Debian 7.2.0-11) 7.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=arm 

All warnings (new ones prefixed by >>):

   In file included from include/linux/swab.h:4:0,
                    from include/uapi/linux/byteorder/big_endian.h:12,
                    from include/linux/byteorder/big_endian.h:4,
                    from arch/arm/include/uapi/asm/byteorder.h:19,
                    from include/asm-generic/bitops/le.h:5,
                    from arch/arm/include/asm/bitops.h:340,
                    from include/linux/bitops.h:37,
                    from include/linux/kernel.h:10,
                    from include/linux/list.h:8,
                    from include/linux/preempt.h:10,
                    from include/linux/spinlock.h:50,
                    from include/linux/seqlock.h:35,
                    from include/linux/time.h:5,
                    from include/uapi/linux/timex.h:56,
                    from include/linux/timex.h:56,
                    from include/linux/clocksource.h:12,
                    from drivers/clocksource/sprd-timer.c:7:
   drivers/clocksource/sprd-timer.c: In function 'sprd_timer_update_counter':
   drivers/clocksource/sprd-timer.c:85:24: warning: right shift count >= width of type [-Wshift-count-overflow]
     writel_relaxed(cycles >> TIMER_VALUE_HI_SHIFT,
                           ^
   include/uapi/linux/swab.h:113:54: note: in definition of macro '__swab32'
    #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
                                                         ^
   include/linux/byteorder/generic.h:87:21: note: in expansion of macro '__cpu_to_le32'
    #define cpu_to_le32 __cpu_to_le32
                        ^~~~~~~~~~~~~
>> drivers/clocksource/sprd-timer.c:85:2: note: in expansion of macro 'writel_relaxed'
     writel_relaxed(cycles >> TIMER_VALUE_HI_SHIFT,
     ^~~~~~~~~~~~~~

vim +/writel_relaxed +85 drivers/clocksource/sprd-timer.c

    79	
    80	static void sprd_timer_update_counter(struct sprd_timer_device *timer,
    81					      unsigned long cycles)
    82	{
    83		writel_relaxed(cycles & TIMER_VALUE_LO_MASK,
    84			       timer->base + TIMER_LOAD_LO);
  > 85		writel_relaxed(cycles >> TIMER_VALUE_HI_SHIFT,
    86			       timer->base + TIMER_LOAD_HI);
    87	}
    88	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 64025 bytes --]

Re: [PATCH 1/2] dt-bindings: clocksource: Add Spreadtrum SC9860 timer

[Rob Herring]

On Fri, Nov 24, 2017 at 01:37:47PM +0800, Baolin Wang wrote:
> This patch adds documentation of device tree bindings for the timers
> found on Spreadtrum SC9860 platform.
> 
> Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com>
> ---
>  .../bindings/timer/spreadtrum,sprd-timer.txt       |   20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/timer/spreadtrum,sprd-timer.txt

Acked-by: Rob Herring <robh@kernel.org>

Re: [PATCH 1/2] dt-bindings: clocksource: Add Spreadtrum SC9860 timer

[Baolin Wang]

Hi,

On 27 November 2017 at 06:17, Rob Herring <robh@kernel.org> wrote:
> On Fri, Nov 24, 2017 at 01:37:47PM +0800, Baolin Wang wrote:
>> This patch adds documentation of device tree bindings for the timers
>> found on Spreadtrum SC9860 platform.
>>
>> Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com>
>> ---
>>  .../bindings/timer/spreadtrum,sprd-timer.txt       |   20 ++++++++++++++++++++
>>  1 file changed, 20 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/timer/spreadtrum,sprd-timer.txt
>
> Acked-by: Rob Herring <robh@kernel.org>

Thanks Rob.

-- 
Baolin Wang
Best Regards

Re: [PATCH 2/2] clocksource: sprd: Add timer driver for Spreadtrum SC9860 platform

[Baolin Wang]

On 25 November 2017 at 13:00, kbuild test robot <lkp@intel.com> wrote:
> Hi Baolin,
>
> Thank you for the patch! Perhaps something to improve:
>
> [auto build test WARNING on tip/timers/core]
> [also build test WARNING on v4.14 next-20171124]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>
> url:    https://github.com/0day-ci/linux/commits/Baolin-Wang/dt-bindings-clocksource-Add-Spreadtrum-SC9860-timer/20171125-090749
> config: arm-allmodconfig (attached as .config)
> compiler: arm-linux-gnueabi-gcc (Debian 7.2.0-11) 7.2.0
> reproduce:
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # save the attached .config to linux build tree
>         make.cross ARCH=arm
>
> All warnings (new ones prefixed by >>):
>
>    In file included from include/linux/swab.h:4:0,
>                     from include/uapi/linux/byteorder/big_endian.h:12,
>                     from include/linux/byteorder/big_endian.h:4,
>                     from arch/arm/include/uapi/asm/byteorder.h:19,
>                     from include/asm-generic/bitops/le.h:5,
>                     from arch/arm/include/asm/bitops.h:340,
>                     from include/linux/bitops.h:37,
>                     from include/linux/kernel.h:10,
>                     from include/linux/list.h:8,
>                     from include/linux/preempt.h:10,
>                     from include/linux/spinlock.h:50,
>                     from include/linux/seqlock.h:35,
>                     from include/linux/time.h:5,
>                     from include/uapi/linux/timex.h:56,
>                     from include/linux/timex.h:56,
>                     from include/linux/clocksource.h:12,
>                     from drivers/clocksource/sprd-timer.c:7:
>    drivers/clocksource/sprd-timer.c: In function 'sprd_timer_update_counter':
>    drivers/clocksource/sprd-timer.c:85:24: warning: right shift count >= width of type [-Wshift-count-overflow]
>      writel_relaxed(cycles >> TIMER_VALUE_HI_SHIFT,

OK. I will fix this warning in next version. Thanks.

>                            ^
>    include/uapi/linux/swab.h:113:54: note: in definition of macro '__swab32'
>     #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
>                                                          ^
>    include/linux/byteorder/generic.h:87:21: note: in expansion of macro '__cpu_to_le32'
>     #define cpu_to_le32 __cpu_to_le32
>                         ^~~~~~~~~~~~~
>>> drivers/clocksource/sprd-timer.c:85:2: note: in expansion of macro 'writel_relaxed'
>      writel_relaxed(cycles >> TIMER_VALUE_HI_SHIFT,
>      ^~~~~~~~~~~~~~
>
> vim +/writel_relaxed +85 drivers/clocksource/sprd-timer.c
>
>     79
>     80  static void sprd_timer_update_counter(struct sprd_timer_device *timer,
>     81                                        unsigned long cycles)
>     82  {
>     83          writel_relaxed(cycles & TIMER_VALUE_LO_MASK,
>     84                         timer->base + TIMER_LOAD_LO);
>   > 85          writel_relaxed(cycles >> TIMER_VALUE_HI_SHIFT,
>     86                         timer->base + TIMER_LOAD_HI);
>     87  }
>     88
>
> ---
> 0-DAY kernel test infrastructure                Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all                   Intel Corporation



-- 
Baolin.wang
Best Regards