Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer updates from Thomas Gleixner:
 "The timer department delivers the following christmas presents:

  Core code:

   - Use proper seqcount initializer to make lockdep happy

   - SPDX annotations and cleanup of license boilerplates

   - Use DEFINE_SHOW_ATTRIBUTE() instead of open coding it

   - Minor cleanups

  Driver code:

   - Add the sched_clock for the arc timer (Alexey Brodkin)

   - Change the file timer names for riscv, rockchip, tegra20, sun4i and
     meson6 (Daniel Lezcano)

   - Add the DT bindings for r8a7796, r8a77470 and r8a774a1 (Biju Das)

   - Remove the early platform driver registration for timer-ti-dm
     (Bartosz Golaszewski)

   - Provide the sched_clock for the riscv timer (Anup Patel)

   - Add support for ARM64 for the imx-gpt and convert the imx-tpm to
     the timer-of API (Anson Huang)

   - Remove useless irq protection for the imx-gpt (Clément Péron)

   - Remove a duplicate function name for the vt8500 (Dan Carpenter)

   - Remove obsolete inclusion of <asm/smp_twd.h> for the tegra20 (Geert
     Uytterhoeven)

   - Demote the prcmu and the custom sched_clock for the dbx500 and the
     ux500 (Linus Walleij)

   - Add a new timer clock for the RDA8810PL (Manivannan Sadhasivam)

   - Rename the macro to stick to the register name and add the delay
     timer (Martin Blumenstingl)

   - Switch the bcm2835 to the SPDX identifier (Stefan Wahren)

   - Fix the interrupt register access on the fttmr010 (Tao Ren)

   - Add missing of_node_put in the initialization path on the
     integrator-ap (Yangtao Li)"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
  dt-bindings: timer: Document RDA8810PL SoC timer
  clocksource/drivers/rda: Add clock driver for RDA8810PL SoC
  clocksource/drivers/meson6: Change name meson6_timer timer-meson6
  clocksource/drivers/sun4i: Change name sun4i_timer to timer-sun4i
  clocksource/drivers/tegra20: Change name tegra20_timer to timer-tegra20
  clocksource/drivers/rockchip: Change name rockchip_timer to timer-rockchip
  clocksource/drivers/riscv: Change name riscv_timer to timer-riscv
  clocksource/drivers/riscv_timer: Provide the sched_clock
  clocksource/drivers/timer-imx-tpm: Specify clock name for timer-of
  clocksource/drivers/fttmr010: Fix invalid interrupt register access
  clocksource/drivers/integrator-ap: Add missing of_node_put()
  clocksource/drivers/bcm2835: Switch to SPDX identifier
  dt-bindings: timer: renesas, cmt: Document r8a774a1 CMT support
  clocksource/drivers/timer-imx-tpm: Convert the driver to timer-of
  clocksource/drivers/arc_timer: Utilize generic sched_clock
  dt-bindings: timer: renesas, cmt: Document r8a77470 CMT support
  dt-bindings: timer: renesas, cmt: Document r8a7796 CMT support
  clocksource/drivers/imx-gpt: Remove unnecessary irq protection
  clocksource/drivers/imx-gpt: Add support for ARM64
  clocksource/drivers/meson6_timer: Implement the ARM delay timer
  ...

Documentation/devicetree/bindings/timer/rda,8810pl-timer.txt

+RDA Micro RDA8810PL Timer
+
+Required properties:
+- compatible      :  "rda,8810pl-timer"
+- reg             :  Offset and length of the register set for the device.
+- interrupts      :  Should contain two interrupts.
+- interrupt-names :  Should be "hwtimer", "ostimer".
+
+Example:
+
+		apb@20900000 {
+			compatible = "simple-bus";
+			...
+			timer@10000 {
+				compatible = "rda,8810pl-timer";
+				reg = <0x10000 0x1000>;
+				interrupts = <16 IRQ_TYPE_LEVEL_HIGH>,
+					     <17 IRQ_TYPE_LEVEL_HIGH>;
+				interrupt-names = "hwtimer", "ostimer";
+			};

Documentation/devicetree/bindings/timer/renesas,cmt.txt

@@ -28,6 +28,10 @@ Required Properties:
     - "renesas,r8a7744-cmt1" for the 48-bit CMT1 device included in r8a7744.
     - "renesas,r8a7745-cmt0" for the 32-bit CMT0 device included in r8a7745.
     - "renesas,r8a7745-cmt1" for the 48-bit CMT1 device included in r8a7745.
+    - "renesas,r8a77470-cmt0" for the 32-bit CMT0 device included in r8a77470.
+    - "renesas,r8a77470-cmt1" for the 48-bit CMT1 device included in r8a77470.
+    - "renesas,r8a774a1-cmt0" for the 32-bit CMT0 device included in r8a774a1.
+    - "renesas,r8a774a1-cmt1" for the 48-bit CMT1 device included in r8a774a1.
     - "renesas,r8a7790-cmt0" for the 32-bit CMT0 device included in r8a7790.
     - "renesas,r8a7790-cmt1" for the 48-bit CMT1 device included in r8a7790.
     - "renesas,r8a7791-cmt0" for the 32-bit CMT0 device included in r8a7791.
@@ -36,6 +40,8 @@ Required Properties:
     - "renesas,r8a7793-cmt1" for the 48-bit CMT1 device included in r8a7793.
     - "renesas,r8a7794-cmt0" for the 32-bit CMT0 device included in r8a7794.
     - "renesas,r8a7794-cmt1" for the 48-bit CMT1 device included in r8a7794.
+    - "renesas,r8a7796-cmt0" for the 32-bit CMT0 device included in r8a7796.
+    - "renesas,r8a7796-cmt1" for the 48-bit CMT1 device included in r8a7796.
     - "renesas,r8a77970-cmt0" for the 32-bit CMT0 device included in r8a77970.
     - "renesas,r8a77970-cmt1" for the 48-bit CMT1 device included in r8a77970.
     - "renesas,r8a77980-cmt0" for the 32-bit CMT0 device included in r8a77980.
@@ -47,9 +53,12 @@ Required Properties:
 		and RZ/G1.
 		These are fallbacks for r8a73a4, R-Car Gen2 and RZ/G1 entries
 		listed above.
-    - "renesas,rcar-gen3-cmt0" for 32-bit CMT0 devices included in R-Car Gen3.
-    - "renesas,rcar-gen3-cmt1" for 48-bit CMT1 devices included in R-Car Gen3.
-		These are fallbacks for R-Car Gen3 entries listed above.
+    - "renesas,rcar-gen3-cmt0" for 32-bit CMT0 devices included in R-Car Gen3
+		and RZ/G2.
+    - "renesas,rcar-gen3-cmt1" for 48-bit CMT1 devices included in R-Car Gen3
+		and RZ/G2.
+		These are fallbacks for R-Car Gen3 and RZ/G2 entries listed
+		above.
 
   - reg: base address and length of the registers block for the timer module.
   - interrupts: interrupt-specifier for the timer, one per channel.

arch/arc/Kconfig

@@ -26,6 +26,7 @@ config ARC
 	select GENERIC_IRQ_SHOW
 	select GENERIC_PCI_IOMAP
 	select GENERIC_PENDING_IRQ if SMP
+	select GENERIC_SCHED_CLOCK
 	select GENERIC_SMP_IDLE_THREAD
 	select HAVE_ARCH_KGDB
 	select HAVE_ARCH_TRACEHOOK

drivers/clocksource/Kconfig

@@ -105,6 +105,14 @@ config OWL_TIMER
 	help
 	  Enables the support for the Actions Semi Owl timer driver.
 
+config RDA_TIMER
+	bool "RDA timer driver" if COMPILE_TEST
+	depends on GENERIC_CLOCKEVENTS
+	select CLKSRC_MMIO
+	select TIMER_OF
+	help
+	  Enables the support for the RDA Micro timer driver.
+
 config SUN4I_TIMER
 	bool "Sun4i timer driver" if COMPILE_TEST
 	depends on HAS_IOMEM
@@ -163,12 +171,6 @@ config CLKSRC_NOMADIK_MTU
 	  to multiple interrupt generating programmable
 	  32-bit free running decrementing counters.
 
-config CLKSRC_NOMADIK_MTU_SCHED_CLOCK
-	bool
-	depends on CLKSRC_NOMADIK_MTU
-	help
-	  Use the Multi Timer Unit as the sched_clock.
-
 config CLKSRC_DBX500_PRCMU
 	bool "Clocksource PRCMU Timer" if COMPILE_TEST
 	depends on HAS_IOMEM
@@ -226,13 +228,6 @@ config INTEGRATOR_AP_TIMER
 	help
 	  Enables support for the Integrator-ap timer.
 
-config CLKSRC_DBX500_PRCMU_SCHED_CLOCK
-	bool "Clocksource PRCMU Timer sched_clock"
-	depends on (CLKSRC_DBX500_PRCMU && !CLKSRC_NOMADIK_MTU_SCHED_CLOCK)
-	default y
-	help
-	  Use the always on PRCMU Timer as sched_clock
-
 config CLKSRC_EFM32
 	bool "Clocksource for Energy Micro's EFM32 SoCs" if !ARCH_EFM32
 	depends on OF && ARM && (ARCH_EFM32 || COMPILE_TEST)
@@ -290,6 +285,7 @@ config CLKSRC_MPS2
 
 config ARC_TIMERS
 	bool "Support for 32-bit TIMERn counters in ARC Cores" if COMPILE_TEST
+	depends on GENERIC_SCHED_CLOCK
 	select TIMER_OF
 	help
 	  These are legacy 32-bit TIMER0 and TIMER1 counters found on all ARC cores
@@ -580,7 +576,7 @@ config H8300_TPU
 
 config CLKSRC_IMX_GPT
 	bool "Clocksource using i.MX GPT" if COMPILE_TEST
-	depends on ARM && CLKDEV_LOOKUP
+	depends on (ARM || ARM64) && CLKDEV_LOOKUP
 	select CLKSRC_MMIO
 
 config CLKSRC_IMX_TPM
@@ -611,7 +607,7 @@ config ATCPIT100_TIMER
 
 config RISCV_TIMER
 	bool "Timer for the RISC-V platform"
-	depends on RISCV
+	depends on GENERIC_SCHED_CLOCK && RISCV
 	default y
 	select TIMER_PROBE
 	select TIMER_OF

drivers/clocksource/Makefile

@@ -20,7 +20,7 @@ obj-$(CONFIG_OMAP_DM_TIMER)	+= timer-ti-dm.o
 obj-$(CONFIG_DW_APB_TIMER)	+= dw_apb_timer.o
 obj-$(CONFIG_DW_APB_TIMER_OF)	+= dw_apb_timer_of.o
 obj-$(CONFIG_FTTMR010_TIMER)	+= timer-fttmr010.o
-obj-$(CONFIG_ROCKCHIP_TIMER)      += rockchip_timer.o
+obj-$(CONFIG_ROCKCHIP_TIMER)      += timer-rockchip.o
 obj-$(CONFIG_CLKSRC_NOMADIK_MTU)	+= nomadik-mtu.o
 obj-$(CONFIG_CLKSRC_DBX500_PRCMU)	+= clksrc-dbx500-prcmu.o
 obj-$(CONFIG_ARMADA_370_XP_TIMER)	+= timer-armada-370-xp.o
@@ -32,10 +32,10 @@ obj-$(CONFIG_MXS_TIMER)		+= mxs_timer.o
 obj-$(CONFIG_CLKSRC_PXA)	+= pxa_timer.o
 obj-$(CONFIG_PRIMA2_TIMER)	+= timer-prima2.o
 obj-$(CONFIG_U300_TIMER)	+= timer-u300.o
-obj-$(CONFIG_SUN4I_TIMER)	+= sun4i_timer.o
+obj-$(CONFIG_SUN4I_TIMER)	+= timer-sun4i.o
 obj-$(CONFIG_SUN5I_HSTIMER)	+= timer-sun5i.o
-obj-$(CONFIG_MESON6_TIMER)	+= meson6_timer.o
-obj-$(CONFIG_TEGRA_TIMER)	+= tegra20_timer.o
+obj-$(CONFIG_MESON6_TIMER)	+= timer-meson6.o
+obj-$(CONFIG_TEGRA_TIMER)	+= timer-tegra20.o
 obj-$(CONFIG_VT8500_TIMER)	+= timer-vt8500.o
 obj-$(CONFIG_NSPIRE_TIMER)	+= timer-zevio.o
 obj-$(CONFIG_BCM_KONA_TIMER)	+= bcm_kona_timer.o
@@ -57,6 +57,7 @@ obj-$(CONFIG_OXNAS_RPS_TIMER)	+= timer-oxnas-rps.o
 obj-$(CONFIG_OWL_TIMER)		+= timer-owl.o
 obj-$(CONFIG_SPRD_TIMER)	+= timer-sprd.o
 obj-$(CONFIG_NPCM7XX_TIMER)	+= timer-npcm7xx.o
+obj-$(CONFIG_RDA_TIMER)		+= timer-rda.o
 
 obj-$(CONFIG_ARC_TIMERS)		+= arc_timer.o
 obj-$(CONFIG_ARM_ARCH_TIMER)		+= arm_arch_timer.o
@@ -78,6 +79,6 @@ obj-$(CONFIG_H8300_TPU)			+= h8300_tpu.o
 obj-$(CONFIG_CLKSRC_ST_LPC)		+= clksrc_st_lpc.o
 obj-$(CONFIG_X86_NUMACHIP)		+= numachip.o
 obj-$(CONFIG_ATCPIT100_TIMER)		+= timer-atcpit100.o
-obj-$(CONFIG_RISCV_TIMER)		+= riscv_timer.o
+obj-$(CONFIG_RISCV_TIMER)		+= timer-riscv.o
 obj-$(CONFIG_CSKY_MP_TIMER)		+= timer-mp-csky.o
 obj-$(CONFIG_GX6605S_TIMER)		+= timer-gx6605s.o

drivers/clocksource/arc_timer.c

@@ -23,6 +23,7 @@
 #include <linux/cpu.h>
 #include <linux/of.h>
 #include <linux/of_irq.h>
+#include <linux/sched_clock.h>
 
 #include <soc/arc/timers.h>
 #include <soc/arc/mcip.h>
@@ -88,6 +89,11 @@ static u64 arc_read_gfrc(struct clocksource *cs)
 	return (((u64)h) << 32) | l;
 }
 
+static notrace u64 arc_gfrc_clock_read(void)
+{
+	return arc_read_gfrc(NULL);
+}
+
 static struct clocksource arc_counter_gfrc = {
 	.name   = "ARConnect GFRC",
 	.rating = 400,
@@ -111,6 +117,8 @@ static int __init arc_cs_setup_gfrc(struct device_node *node)
 	if (ret)
 		return ret;
 
+	sched_clock_register(arc_gfrc_clock_read, 64, arc_timer_freq);
+
 	return clocksource_register_hz(&arc_counter_gfrc, arc_timer_freq);
 }
 TIMER_OF_DECLARE(arc_gfrc, "snps,archs-timer-gfrc", arc_cs_setup_gfrc);
@@ -139,6 +147,11 @@ static u64 arc_read_rtc(struct clocksource *cs)
 	return (((u64)h) << 32) | l;
 }
 
+static notrace u64 arc_rtc_clock_read(void)
+{
+	return arc_read_rtc(NULL);
+}
+
 static struct clocksource arc_counter_rtc = {
 	.name   = "ARCv2 RTC",
 	.rating = 350,
@@ -170,6 +183,8 @@ static int __init arc_cs_setup_rtc(struct device_node *node)
 
 	write_aux_reg(AUX_RTC_CTRL, 1);
 
+	sched_clock_register(arc_rtc_clock_read, 64, arc_timer_freq);
+
 	return clocksource_register_hz(&arc_counter_rtc, arc_timer_freq);
 }
 TIMER_OF_DECLARE(arc_rtc, "snps,archs-timer-rtc", arc_cs_setup_rtc);
@@ -185,6 +200,11 @@ static u64 arc_read_timer1(struct clocksource *cs)
 	return (u64) read_aux_reg(ARC_REG_TIMER1_CNT);
 }
 
+static notrace u64 arc_timer1_clock_read(void)
+{
+	return arc_read_timer1(NULL);
+}
+
 static struct clocksource arc_counter_timer1 = {
 	.name   = "ARC Timer1",
 	.rating = 300,
@@ -209,6 +229,8 @@ static int __init arc_cs_setup_timer1(struct device_node *node)
 	write_aux_reg(ARC_REG_TIMER1_CNT, 0);
 	write_aux_reg(ARC_REG_TIMER1_CTRL, TIMER_CTRL_NH);
 
+	sched_clock_register(arc_timer1_clock_read, 32, arc_timer_freq);
+
 	return clocksource_register_hz(&arc_counter_timer1, arc_timer_freq);
 }
 

drivers/clocksource/bcm2835_timer.c

+// SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright 2012 Simon Arlott
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
 #include <linux/bitops.h>

drivers/clocksource/clksrc-dbx500-prcmu.c

@@ -15,7 +15,6 @@
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/clockchips.h>
-#include <linux/sched_clock.h>
 
 #define RATE_32K		32768
 
@@ -26,8 +25,6 @@
 #define PRCMU_TIMER_DOWNCOUNT	0x4
 #define PRCMU_TIMER_MODE	0x8
 
-#define SCHED_CLOCK_MIN_WRAP 131072 /* 2^32 / 32768 */
-
 static void __iomem *clksrc_dbx500_timer_base;
 
 static u64 notrace clksrc_dbx500_prcmu_read(struct clocksource *cs)
@@ -46,24 +43,12 @@ static u64 notrace clksrc_dbx500_prcmu_read(struct clocksource *cs)
 
 static struct clocksource clocksource_dbx500_prcmu = {
 	.name		= "dbx500-prcmu-timer",
-	.rating		= 300,
+	.rating		= 100,
 	.read		= clksrc_dbx500_prcmu_read,
 	.mask		= CLOCKSOURCE_MASK(32),
-	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_SUSPEND_NONSTOP,
 };
 
-#ifdef CONFIG_CLKSRC_DBX500_PRCMU_SCHED_CLOCK
-
-static u64 notrace dbx500_prcmu_sched_clock_read(void)
-{
-	if (unlikely(!clksrc_dbx500_timer_base))
-		return 0;
-
-	return clksrc_dbx500_prcmu_read(&clocksource_dbx500_prcmu);
-}
-
-#endif
-
 static int __init clksrc_dbx500_prcmu_init(struct device_node *node)
 {
 	clksrc_dbx500_timer_base = of_iomap(node, 0);
@@ -81,9 +66,6 @@ static int __init clksrc_dbx500_prcmu_init(struct device_node *node)
 		writel(TIMER_DOWNCOUNT_VAL,
 		       clksrc_dbx500_timer_base + PRCMU_TIMER_REF);
 	}
-#ifdef CONFIG_CLKSRC_DBX500_PRCMU_SCHED_CLOCK
-	sched_clock_register(dbx500_prcmu_sched_clock_read, 32, RATE_32K);
-#endif
 	return clocksource_register_hz(&clocksource_dbx500_prcmu, RATE_32K);
 }
 TIMER_OF_DECLARE(dbx500_prcmu, "stericsson,db8500-prcmu-timer-4",

drivers/clocksource/nomadik-mtu.c

@@ -69,7 +69,6 @@ static u32 clk_prescale;
 static u32 nmdk_cycle;		/* write-once */
 static struct delay_timer mtu_delay_timer;
 
-#ifdef CONFIG_CLKSRC_NOMADIK_MTU_SCHED_CLOCK
 /*
  * Override the global weak sched_clock symbol with this
  * local implementation which uses the clocksource to get some
@@ -82,7 +81,6 @@ static u64 notrace nomadik_read_sched_clock(void)
 
 	return -readl(mtu_base + MTU_VAL(0));
 }
-#endif
 
 static unsigned long nmdk_timer_read_current_timer(void)
 {
@@ -234,9 +232,7 @@ static int __init nmdk_timer_init(void __iomem *base, int irq,
 		return ret;
 	}
 
-#ifdef CONFIG_CLKSRC_NOMADIK_MTU_SCHED_CLOCK
 	sched_clock_register(nomadik_read_sched_clock, 32, rate);
-#endif
 
 	/* Timer 1 is used for events, register irq and clockevents */
 	setup_irq(irq, &nmdk_timer_irq);

drivers/clocksource/timer-fttmr010.c

@@ -21,7 +21,7 @@
 #include <linux/delay.h>
 
 /*
- * Register definitions for the timers
+ * Register definitions common for all the timer variants.
  */
 #define TIMER1_COUNT		(0x00)
 #define TIMER1_LOAD		(0x04)
@@ -36,9 +36,10 @@
 #define TIMER3_MATCH1		(0x28)
 #define TIMER3_MATCH2		(0x2c)
 #define TIMER_CR		(0x30)
-#define TIMER_INTR_STATE	(0x34)
-#define TIMER_INTR_MASK		(0x38)
 
+/*
+ * Control register (TMC30) bit fields for fttmr010/gemini/moxart timers.
+ */
 #define TIMER_1_CR_ENABLE	BIT(0)
 #define TIMER_1_CR_CLOCK	BIT(1)
 #define TIMER_1_CR_INT		BIT(2)
@@ -53,8 +54,9 @@
 #define TIMER_3_CR_UPDOWN	BIT(11)
 
 /*
- * The Aspeed AST2400 moves bits around in the control register
- * and lacks bits for setting the timer to count upwards.
+ * Control register (TMC30) bit fields for aspeed ast2400/ast2500 timers.
+ * The aspeed timers move bits around in the control register and lacks
+ * bits for setting the timer to count upwards.
  */
 #define TIMER_1_CR_ASPEED_ENABLE	BIT(0)
 #define TIMER_1_CR_ASPEED_CLOCK		BIT(1)
@@ -66,6 +68,18 @@
 #define TIMER_3_CR_ASPEED_CLOCK		BIT(9)
 #define TIMER_3_CR_ASPEED_INT		BIT(10)
 
+/*
+ * Interrupt status/mask register definitions for fttmr010/gemini/moxart
+ * timers.
+ * The registers don't exist and they are not needed on aspeed timers
+ * because:
+ *   - aspeed timer overflow interrupt is controlled by bits in Control
+ *     Register (TMC30).
+ *   - aspeed timers always generate interrupt when either one of the
+ *     Match registers equals to Status register.
+ */
+#define TIMER_INTR_STATE	(0x34)
+#define TIMER_INTR_MASK		(0x38)
 #define TIMER_1_INT_MATCH1	BIT(0)
 #define TIMER_1_INT_MATCH2	BIT(1)
 #define TIMER_1_INT_OVERFLOW	BIT(2)
@@ -80,7 +94,7 @@
 struct fttmr010 {
 	void __iomem *base;
 	unsigned int tick_rate;
-	bool count_down;
+	bool is_aspeed;
 	u32 t1_enable_val;
 	struct clock_event_device clkevt;
 #ifdef CONFIG_ARM
@@ -130,7 +144,7 @@ static int fttmr010_timer_set_next_event(unsigned long cycles,
 	cr &= ~fttmr010->t1_enable_val;
 	writel(cr, fttmr010->base + TIMER_CR);
 
-	if (fttmr010->count_down) {
+	if (fttmr010->is_aspeed) {
 		/*
 		 * ASPEED Timer Controller will load TIMER1_LOAD register
 		 * into TIMER1_COUNT register when the timer is re-enabled.
@@ -175,16 +189,17 @@ static int fttmr010_timer_set_oneshot(struct clock_event_device *evt)
 
 	/* Setup counter start from 0 or ~0 */
 	writel(0, fttmr010->base + TIMER1_COUNT);
-	if (fttmr010->count_down)
+	if (fttmr010->is_aspeed) {
 		writel(~0, fttmr010->base + TIMER1_LOAD);
-	else
+	} else {
 		writel(0, fttmr010->base + TIMER1_LOAD);
 
-	/* Enable interrupt */
-	cr = readl(fttmr010->base + TIMER_INTR_MASK);
-	cr &= ~(TIMER_1_INT_OVERFLOW | TIMER_1_INT_MATCH2);
-	cr |= TIMER_1_INT_MATCH1;
-	writel(cr, fttmr010->base + TIMER_INTR_MASK);
+		/* Enable interrupt */
+		cr = readl(fttmr010->base + TIMER_INTR_MASK);
+		cr &= ~(TIMER_1_INT_OVERFLOW | TIMER_1_INT_MATCH2);
+		cr |= TIMER_1_INT_MATCH1;
+		writel(cr, fttmr010->base + TIMER_INTR_MASK);
+	}
 
 	return 0;
 }
@@ -201,9 +216,8 @@ static int fttmr010_timer_set_periodic(struct clock_event_device *evt)
 	writel(cr, fttmr010->base + TIMER_CR);
 
 	/* Setup timer to fire at 1/HZ intervals. */
-	if (fttmr010->count_down) {
+	if (fttmr010->is_aspeed) {
 		writel(period, fttmr010->base + TIMER1_LOAD);
-		writel(0, fttmr010->base + TIMER1_MATCH1);
 	} else {
 		cr = 0xffffffff - (period - 1);
 		writel(cr, fttmr010->base + TIMER1_COUNT);
@@ -281,23 +295,21 @@ static int __init fttmr010_common_init(struct device_node *np, bool is_aspeed)
 	}
 
 	/*
-	 * The Aspeed AST2400 moves bits around in the control register,
-	 * otherwise it works the same.
+	 * The Aspeed timers move bits around in the control register.
 	 */
 	if (is_aspeed) {
 		fttmr010->t1_enable_val = TIMER_1_CR_ASPEED_ENABLE |
 			TIMER_1_CR_ASPEED_INT;
-		/* Downward not available */
-		fttmr010->count_down = true;
+		fttmr010->is_aspeed = true;
 	} else {
 		fttmr010->t1_enable_val = TIMER_1_CR_ENABLE | TIMER_1_CR_INT;
-	}
 
-	/*
-	 * Reset the interrupt mask and status
-	 */
-	writel(TIMER_INT_ALL_MASK, fttmr010->base + TIMER_INTR_MASK);
-	writel(0, fttmr010->base + TIMER_INTR_STATE);
+		/*
+		 * Reset the interrupt mask and status
+		 */
+		writel(TIMER_INT_ALL_MASK, fttmr010->base + TIMER_INTR_MASK);
+		writel(0, fttmr010->base + TIMER_INTR_STATE);
+	}
 
 	/*
 	 * Enable timer 1 count up, timer 2 count up, except on Aspeed,
@@ -306,9 +318,8 @@ static int __init fttmr010_common_init(struct device_node *np, bool is_aspeed)
 	if (is_aspeed)
 		val = TIMER_2_CR_ASPEED_ENABLE;
 	else {
-		val = TIMER_2_CR_ENABLE;
-		if (!fttmr010->count_down)
-			val |= TIMER_1_CR_UPDOWN | TIMER_2_CR_UPDOWN;
+		val = TIMER_2_CR_ENABLE | TIMER_1_CR_UPDOWN |
+			TIMER_2_CR_UPDOWN;
 	}
 	writel(val, fttmr010->base + TIMER_CR);
 
@@ -321,7 +332,7 @@ static int __init fttmr010_common_init(struct device_node *np, bool is_aspeed)
 	writel(0, fttmr010->base + TIMER2_MATCH1);
 	writel(0, fttmr010->base + TIMER2_MATCH2);
 
-	if (fttmr010->count_down) {
+	if (fttmr010->is_aspeed) {
 		writel(~0, fttmr010->base + TIMER2_LOAD);
 		clocksource_mmio_init(fttmr010->base + TIMER2_COUNT,
 				      "FTTMR010-TIMER2",
@@ -371,7 +382,7 @@ static int __init fttmr010_common_init(struct device_node *np, bool is_aspeed)
 
 #ifdef CONFIG_ARM
 	/* Also use this timer for delays */
-	if (fttmr010->count_down)
+	if (fttmr010->is_aspeed)
 		fttmr010->delay_timer.read_current_timer =
 			fttmr010_read_current_timer_down;
 	else

drivers/clocksource/timer-imx-gpt.c

@@ -141,21 +141,25 @@ static u64 notrace mxc_read_sched_clock(void)
 	return sched_clock_reg ? readl_relaxed(sched_clock_reg) : 0;
 }
 
+#if defined(CONFIG_ARM)
 static struct delay_timer imx_delay_timer;
 
 static unsigned long imx_read_current_timer(void)
 {
 	return readl_relaxed(sched_clock_reg);
 }
+#endif
 
 static int __init mxc_clocksource_init(struct imx_timer *imxtm)
 {
 	unsigned int c = clk_get_rate(imxtm->clk_per);
 	void __iomem *reg = imxtm->base + imxtm->gpt->reg_tcn;
 
+#if defined(CONFIG_ARM)
 	imx_delay_timer.read_current_timer = &imx_read_current_timer;
 	imx_delay_timer.freq = c;
 	register_current_timer_delay(&imx_delay_timer);
+#endif
 
 	sched_clock_reg = reg;
 
@@ -198,15 +202,8 @@ static int v2_set_next_event(unsigned long evt,
 static int mxc_shutdown(struct clock_event_device *ced)
 {
 	struct imx_timer *imxtm = to_imx_timer(ced);
-	unsigned long flags;
 	u32 tcn;
 
-	/*
-	 * The timer interrupt generation is disabled at least
-	 * for enough time to call mxc_set_next_event()
-	 */
-	local_irq_save(flags);
-
 	/* Disable interrupt in GPT module */
 	imxtm->gpt->gpt_irq_disable(imxtm);
 
@@ -221,21 +218,12 @@ static int mxc_shutdown(struct clock_event_device *ced)
 	printk(KERN_INFO "%s: changing mode\n", __func__);
 #endif /* DEBUG */
 
-	local_irq_restore(flags);
-
 	return 0;
 }
 
 static int mxc_set_oneshot(struct clock_event_device *ced)
 {
 	struct imx_timer *imxtm = to_imx_timer(ced);
-	unsigned long flags;
-
-	/*
-	 * The timer interrupt generation is disabled at least
-	 * for enough time to call mxc_set_next_event()
-	 */
-	local_irq_save(flags);
 
 	/* Disable interrupt in GPT module */
 	imxtm->gpt->gpt_irq_disable(imxtm);
@@ -260,7 +248,6 @@ static int mxc_set_oneshot(struct clock_event_device *ced)
 	 * mode switching
 	 */
 	imxtm->gpt->gpt_irq_enable(imxtm);
-	local_irq_restore(flags);
 
 	return 0;
 }

drivers/clocksource/timer-imx-tpm.c

@@ -12,6 +12,8 @@
 #include <linux/of_irq.h>
 #include <linux/sched_clock.h>
 
+#include "timer-of.h"
+
 #define TPM_PARAM			0x4
 #define TPM_PARAM_WIDTH_SHIFT		16
 #define TPM_PARAM_WIDTH_MASK		(0xff << 16)
@@ -33,9 +35,7 @@
 #define TPM_C0V				0x24
 
 static int counter_width;
-static int rating;
 static void __iomem *timer_base;
-static struct clock_event_device clockevent_tpm;
 
 static inline void tpm_timer_disable(void)
 {
@@ -80,19 +80,6 @@ static u64 notrace tpm_read_sched_clock(void)
 	return tpm_read_counter();
 }
 
-static int __init tpm_clocksource_init(unsigned long rate)
-{
-	tpm_delay_timer.read_current_timer = &tpm_read_current_timer;
-	tpm_delay_timer.freq = rate;
-	register_current_timer_delay(&tpm_delay_timer);
-
-	sched_clock_register(tpm_read_sched_clock, counter_width, rate);
-
-	return clocksource_mmio_init(timer_base + TPM_CNT, "imx-tpm",
-				     rate, rating, counter_width,
-				     clocksource_mmio_readl_up);
-}
-
 static int tpm_set_next_event(unsigned long delta,
 				struct clock_event_device *evt)
 {
@@ -137,74 +124,80 @@ static irqreturn_t tpm_timer_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static struct clock_event_device clockevent_tpm = {
-	.name			= "i.MX7ULP TPM Timer",
-	.features		= CLOCK_EVT_FEAT_ONESHOT,
-	.set_state_oneshot	= tpm_set_state_oneshot,
-	.set_next_event		= tpm_set_next_event,
-	.set_state_shutdown	= tpm_set_state_shutdown,
+static struct timer_of to_tpm = {
+	.flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
+	.clkevt = {
+		.name			= "i.MX7ULP TPM Timer",
+		.rating			= 200,
+		.features		= CLOCK_EVT_FEAT_ONESHOT,
+		.set_state_shutdown	= tpm_set_state_shutdown,
+		.set_state_oneshot	= tpm_set_state_oneshot,
+		.set_next_event		= tpm_set_next_event,
+		.cpumask		= cpu_possible_mask,
+	},
+	.of_irq = {
+		.handler		= tpm_timer_interrupt,
+		.flags			= IRQF_TIMER | IRQF_IRQPOLL,
+	},
+	.of_clk = {
+		.name = "per",
+	},
 };
 
-static int __init tpm_clockevent_init(unsigned long rate, int irq)
+static int __init tpm_clocksource_init(void)
 {
-	int ret;
+	tpm_delay_timer.read_current_timer = &tpm_read_current_timer;
+	tpm_delay_timer.freq = timer_of_rate(&to_tpm) >> 3;
+	register_current_timer_delay(&tpm_delay_timer);
 
-	ret = request_irq(irq, tpm_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
-			  "i.MX7ULP TPM Timer", &clockevent_tpm);
+	sched_clock_register(tpm_read_sched_clock, counter_width,
+			     timer_of_rate(&to_tpm) >> 3);
 
-	clockevent_tpm.rating = rating;
-	clockevent_tpm.cpumask = cpumask_of(0);
-	clockevent_tpm.irq = irq;
-	clockevents_config_and_register(&clockevent_tpm, rate, 300,
-					GENMASK(counter_width - 1, 1));
+	return clocksource_mmio_init(timer_base + TPM_CNT,
+				     "imx-tpm",
+				     timer_of_rate(&to_tpm) >> 3,
+				     to_tpm.clkevt.rating,
+				     counter_width,
+				     clocksource_mmio_readl_up);
+}
 
-	return ret;
+static void __init tpm_clockevent_init(void)
+{
+	clockevents_config_and_register(&to_tpm.clkevt,
+					timer_of_rate(&to_tpm) >> 3,
+					300,
+					GENMASK(counter_width - 1,
+					1));
 }
 
 static int __init tpm_timer_init(struct device_node *np)
 {
-	struct clk *ipg, *per;
-	int irq, ret;
-	u32 rate;
-
-	timer_base = of_iomap(np, 0);
-	if (!timer_base) {
-		pr_err("tpm: failed to get base address\n");
-		return -ENXIO;
-	}
-
-	irq = irq_of_parse_and_map(np, 0);
-	if (!irq) {
-		pr_err("tpm: failed to get irq\n");
-		ret = -ENOENT;
-		goto err_iomap;
-	}
+	struct clk *ipg;
+	int ret;
 
 	ipg = of_clk_get_by_name(np, "ipg");
-	per = of_clk_get_by_name(np, "per");
-	if (IS_ERR(ipg) || IS_ERR(per)) {
-		pr_err("tpm: failed to get ipg or per clk\n");
-		ret = -ENODEV;
-		goto err_clk_get;
+	if (IS_ERR(ipg)) {
+		pr_err("tpm: failed to get ipg clk\n");
+		return -ENODEV;
 	}
-
 	/* enable clk before accessing registers */
 	ret = clk_prepare_enable(ipg);
 	if (ret) {
 		pr_err("tpm: ipg clock enable failed (%d)\n", ret);
-		goto err_clk_get;
+		clk_put(ipg);
+		return ret;
 	}
 
-	ret = clk_prepare_enable(per);
-	if (ret) {
-		pr_err("tpm: per clock enable failed (%d)\n", ret);
-		goto err_per_clk_enable;
-	}
+	ret = timer_of_init(np, &to_tpm);
+	if (ret)
+		return ret;
+
+	timer_base = timer_of_base(&to_tpm);
 
-	counter_width = (readl(timer_base + TPM_PARAM) & TPM_PARAM_WIDTH_MASK)
-		>> TPM_PARAM_WIDTH_SHIFT;
+	counter_width = (readl(timer_base + TPM_PARAM)
+		& TPM_PARAM_WIDTH_MASK) >> TPM_PARAM_WIDTH_SHIFT;
 	/* use rating 200 for 32-bit counter and 150 for 16-bit counter */
-	rating = counter_width == 0x20 ? 200 : 150;
+	to_tpm.clkevt.rating = counter_width == 0x20 ? 200 : 150;
 
 	/*
 	 * Initialize tpm module to a known state
@@ -229,29 +222,13 @@ static int __init tpm_timer_init(struct device_node *np)
 	writel(TPM_SC_CMOD_INC_PER_CNT |
 		(counter_width == 0x20 ?
 		TPM_SC_CMOD_DIV_DEFAULT : TPM_SC_CMOD_DIV_MAX),
-		     timer_base + TPM_SC);
+		timer_base + TPM_SC);
 
 	/* set MOD register to maximum for free running mode */
 	writel(GENMASK(counter_width - 1, 0), timer_base + TPM_MOD);
 
-	rate = clk_get_rate(per) >> 3;
-	ret = tpm_clocksource_init(rate);
-	if (ret)
-		goto err_per_clk_enable;
-
-	ret = tpm_clockevent_init(rate, irq);
-	if (ret)
-		goto err_per_clk_enable;
-
-	return 0;
+	tpm_clockevent_init();
 
-err_per_clk_enable:
-	clk_disable_unprepare(ipg);
-err_clk_get:
-	clk_put(per);
-	clk_put(ipg);
-err_iomap:
-	iounmap(timer_base);
-	return ret;
+	return tpm_clocksource_init();
 }
 TIMER_OF_DECLARE(imx7ulp, "fsl,imx7ulp-tpm", tpm_timer_init);

drivers/clocksource/timer-integrator-ap.c

@@ -181,8 +181,7 @@ static int __init integrator_ap_timer_init_of(struct device_node *node)
 	int irq;
 	struct clk *clk;
 	unsigned long rate;
-	struct device_node *pri_node;
-	struct device_node *sec_node;
+	struct device_node *alias_node;
 
 	base = of_io_request_and_map(node, 0, "integrator-timer");
 	if (IS_ERR(base))
@@ -204,7 +203,18 @@ static int __init integrator_ap_timer_init_of(struct device_node *node)
 		return err;
 	}
 
-	pri_node = of_find_node_by_path(path);
+	alias_node = of_find_node_by_path(path);
+
+	/*
+	 * The pointer is used as an identifier not as a pointer, we
+	 * can drop the refcount on the of__node immediately after
+	 * getting it.
+	 */
+	of_node_put(alias_node);
+
+	if (node == alias_node)
+		/* The primary timer lacks IRQ, use as clocksource */
+		return integrator_clocksource_init(rate, base);
 
 	err = of_property_read_string(of_aliases,
 				"arm,timer-secondary", &path);
@@ -213,14 +223,11 @@ static int __init integrator_ap_timer_init_of(struct device_node *node)
 		return err;
 	}
 
+	alias_node = of_find_node_by_path(path);
 
-	sec_node = of_find_node_by_path(path);
-
-	if (node == pri_node)
-		/* The primary timer lacks IRQ, use as clocksource */
-		return integrator_clocksource_init(rate, base);
+	of_node_put(alias_node);
 
-	if (node == sec_node) {
+	if (node == alias_node) {
 		/* The secondary timer will drive the clock event */
 		irq = irq_of_parse_and_map(node, 0);
 		return integrator_clockevent_init(rate, base, irq);

drivers/clocksource/meson6_timer.c → drivers/clocksource/timer-meson6.c

@@ -10,6 +10,8 @@
  * warranty of any kind, whether express or implied.
  */
 
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
 #include <linux/clk.h>
 #include <linux/clockchips.h>
 #include <linux/interrupt.h>
@@ -20,80 +22,112 @@
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 
-#define CED_ID			0
-#define CSD_ID			4
+#ifdef CONFIG_ARM
+#include <linux/delay.h>
+#endif
+
+#define MESON_ISA_TIMER_MUX					0x00
+#define MESON_ISA_TIMER_MUX_TIMERD_EN				BIT(19)
+#define MESON_ISA_TIMER_MUX_TIMERC_EN				BIT(18)
+#define MESON_ISA_TIMER_MUX_TIMERB_EN				BIT(17)
+#define MESON_ISA_TIMER_MUX_TIMERA_EN				BIT(16)
+#define MESON_ISA_TIMER_MUX_TIMERD_MODE				BIT(15)
+#define MESON_ISA_TIMER_MUX_TIMERC_MODE				BIT(14)
+#define MESON_ISA_TIMER_MUX_TIMERB_MODE				BIT(13)
+#define MESON_ISA_TIMER_MUX_TIMERA_MODE				BIT(12)
+#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_MASK		GENMASK(10, 8)
+#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_SYSTEM_CLOCK	0x0
+#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_1US		0x1
+#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_10US		0x2
+#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_100US		0x3
+#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_1MS		0x4
+#define MESON_ISA_TIMER_MUX_TIMERD_INPUT_CLOCK_MASK		GENMASK(7, 6)
+#define MESON_ISA_TIMER_MUX_TIMERC_INPUT_CLOCK_MASK		GENMASK(5, 4)
+#define MESON_ISA_TIMER_MUX_TIMERB_INPUT_CLOCK_MASK		GENMASK(3, 2)
+#define MESON_ISA_TIMER_MUX_TIMERA_INPUT_CLOCK_MASK		GENMASK(1, 0)
+#define MESON_ISA_TIMER_MUX_TIMERABCD_INPUT_CLOCK_1US		0x0
+#define MESON_ISA_TIMER_MUX_TIMERABCD_INPUT_CLOCK_10US		0x1
+#define MESON_ISA_TIMER_MUX_TIMERABCD_INPUT_CLOCK_100US		0x0
+#define MESON_ISA_TIMER_MUX_TIMERABCD_INPUT_CLOCK_1MS		0x3
+
+#define MESON_ISA_TIMERA					0x04
+#define MESON_ISA_TIMERB					0x08
+#define MESON_ISA_TIMERC					0x0c
+#define MESON_ISA_TIMERD					0x10
+#define MESON_ISA_TIMERE					0x14
 
-#define TIMER_ISA_MUX		0
-#define TIMER_ISA_VAL(t)	(((t) + 1) << 2)
-
-#define TIMER_INPUT_BIT(t)	(2 * (t))
-#define TIMER_ENABLE_BIT(t)	(16 + (t))
-#define TIMER_PERIODIC_BIT(t)	(12 + (t))
-
-#define TIMER_CED_INPUT_MASK	(3UL << TIMER_INPUT_BIT(CED_ID))
-#define TIMER_CSD_INPUT_MASK	(7UL << TIMER_INPUT_BIT(CSD_ID))
+static void __iomem *timer_base;
 
-#define TIMER_CED_UNIT_1US	0
-#define TIMER_CSD_UNIT_1US	1
+#ifdef CONFIG_ARM
+static unsigned long meson6_read_current_timer(void)
+{
+	return readl_relaxed(timer_base + MESON_ISA_TIMERE);
+}
 
-static void __iomem *timer_base;
+static struct delay_timer meson6_delay_timer = {
+	.read_current_timer = meson6_read_current_timer,
+	.freq = 1000 * 1000,
+};
+#endif
 
 static u64 notrace meson6_timer_sched_read(void)
 {
-	return (u64)readl(timer_base + TIMER_ISA_VAL(CSD_ID));
+	return (u64)readl(timer_base + MESON_ISA_TIMERE);
 }
 
-static void meson6_clkevt_time_stop(unsigned char timer)
+static void meson6_clkevt_time_stop(void)
 {
-	u32 val = readl(timer_base + TIMER_ISA_MUX);
+	u32 val = readl(timer_base + MESON_ISA_TIMER_MUX);
 
-	writel(val & ~TIMER_ENABLE_BIT(timer), timer_base + TIMER_ISA_MUX);
+	writel(val & ~MESON_ISA_TIMER_MUX_TIMERA_EN,
+	       timer_base + MESON_ISA_TIMER_MUX);
 }
 
-static void meson6_clkevt_time_setup(unsigned char timer, unsigned long delay)
+static void meson6_clkevt_time_setup(unsigned long delay)
 {
-	writel(delay, timer_base + TIMER_ISA_VAL(timer));
+	writel(delay, timer_base + MESON_ISA_TIMERA);
 }
 
-static void meson6_clkevt_time_start(unsigned char timer, bool periodic)
+static void meson6_clkevt_time_start(bool periodic)
 {
-	u32 val = readl(timer_base + TIMER_ISA_MUX);
+	u32 val = readl(timer_base + MESON_ISA_TIMER_MUX);
 
 	if (periodic)
-		val |= TIMER_PERIODIC_BIT(timer);
+		val |= MESON_ISA_TIMER_MUX_TIMERA_MODE;
 	else
-		val &= ~TIMER_PERIODIC_BIT(timer);
+		val &= ~MESON_ISA_TIMER_MUX_TIMERA_MODE;
 
-	writel(val | TIMER_ENABLE_BIT(timer), timer_base + TIMER_ISA_MUX);
+	writel(val | MESON_ISA_TIMER_MUX_TIMERA_EN,
+	       timer_base + MESON_ISA_TIMER_MUX);
 }
 
 static int meson6_shutdown(struct clock_event_device *evt)
 {
-	meson6_clkevt_time_stop(CED_ID);
+	meson6_clkevt_time_stop();
 	return 0;
 }
 
 static int meson6_set_oneshot(struct clock_event_device *evt)
 {
-	meson6_clkevt_time_stop(CED_ID);
-	meson6_clkevt_time_start(CED_ID, false);
+	meson6_clkevt_time_stop();
+	meson6_clkevt_time_start(false);
 	return 0;
 }
 
 static int meson6_set_periodic(struct clock_event_device *evt)
 {
-	meson6_clkevt_time_stop(CED_ID);
-	meson6_clkevt_time_setup(CED_ID, USEC_PER_SEC / HZ - 1);
-	meson6_clkevt_time_start(CED_ID, true);
+	meson6_clkevt_time_stop();
+	meson6_clkevt_time_setup(USEC_PER_SEC / HZ - 1);
+	meson6_clkevt_time_start(true);
 	return 0;
 }
 
 static int meson6_clkevt_next_event(unsigned long evt,
 				    struct clock_event_device *unused)
 {
-	meson6_clkevt_time_stop(CED_ID);
-	meson6_clkevt_time_setup(CED_ID, evt);
-	meson6_clkevt_time_start(CED_ID, false);
+	meson6_clkevt_time_stop();
+	meson6_clkevt_time_setup(evt);
+	meson6_clkevt_time_start(false);
 
 	return 0;
 }
@@ -144,22 +178,24 @@ static int __init meson6_timer_init(struct device_node *node)
 	}
 
 	/* Set 1us for timer E */
-	val = readl(timer_base + TIMER_ISA_MUX);
-	val &= ~TIMER_CSD_INPUT_MASK;
-	val |= TIMER_CSD_UNIT_1US << TIMER_INPUT_BIT(CSD_ID);
-	writel(val, timer_base + TIMER_ISA_MUX);
+	val = readl(timer_base + MESON_ISA_TIMER_MUX);
+	val &= ~MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_MASK;
+	val |= FIELD_PREP(MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_MASK,
+			  MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_1US);
+	writel(val, timer_base + MESON_ISA_TIMER_MUX);
 
 	sched_clock_register(meson6_timer_sched_read, 32, USEC_PER_SEC);
-	clocksource_mmio_init(timer_base + TIMER_ISA_VAL(CSD_ID), node->name,
+	clocksource_mmio_init(timer_base + MESON_ISA_TIMERE, node->name,
 			      1000 * 1000, 300, 32, clocksource_mmio_readl_up);
 
 	/* Timer A base 1us */
-	val &= ~TIMER_CED_INPUT_MASK;
-	val |= TIMER_CED_UNIT_1US << TIMER_INPUT_BIT(CED_ID);
-	writel(val, timer_base + TIMER_ISA_MUX);
+	val &= ~MESON_ISA_TIMER_MUX_TIMERA_INPUT_CLOCK_MASK;
+	val |= FIELD_PREP(MESON_ISA_TIMER_MUX_TIMERA_INPUT_CLOCK_MASK,
+			  MESON_ISA_TIMER_MUX_TIMERABCD_INPUT_CLOCK_1US);
+	writel(val, timer_base + MESON_ISA_TIMER_MUX);
 
 	/* Stop the timer A */
-	meson6_clkevt_time_stop(CED_ID);
+	meson6_clkevt_time_stop();
 
 	ret = setup_irq(irq, &meson6_timer_irq);
 	if (ret) {
@@ -172,6 +208,12 @@ static int __init meson6_timer_init(struct device_node *node)
 
 	clockevents_config_and_register(&meson6_clockevent, USEC_PER_SEC,
 					1, 0xfffe);
+
+#ifdef CONFIG_ARM
+	/* Also use MESON_ISA_TIMERE for delays */
+	register_current_timer_delay(&meson6_delay_timer);
+#endif
+
 	return 0;
 }
 TIMER_OF_DECLARE(meson6, "amlogic,meson6-timer",

drivers/clocksource/timer-rda.c

+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * RDA8810PL SoC timer driver
+ *
+ * Copyright RDA Microelectronics Company Limited
+ * Copyright (c) 2017 Andreas Färber
+ * Copyright (c) 2018 Manivannan Sadhasivam
+ *
+ * RDA8810PL has two independent timers: OSTIMER (56 bit) and HWTIMER (64 bit).
+ * Each timer provides optional interrupt support. In this driver, OSTIMER is
+ * used for clockevents and HWTIMER is used for clocksource.
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+
+#include "timer-of.h"
+
+#define RDA_OSTIMER_LOADVAL_L	0x000
+#define RDA_OSTIMER_CTRL	0x004
+#define RDA_HWTIMER_LOCKVAL_L	0x024
+#define RDA_HWTIMER_LOCKVAL_H	0x028
+#define RDA_TIMER_IRQ_MASK_SET	0x02c
+#define RDA_TIMER_IRQ_MASK_CLR	0x030
+#define RDA_TIMER_IRQ_CLR	0x034
+
+#define RDA_OSTIMER_CTRL_ENABLE		BIT(24)
+#define RDA_OSTIMER_CTRL_REPEAT		BIT(28)
+#define RDA_OSTIMER_CTRL_LOAD		BIT(30)
+
+#define RDA_TIMER_IRQ_MASK_OSTIMER	BIT(0)
+
+#define RDA_TIMER_IRQ_CLR_OSTIMER	BIT(0)
+
+static int rda_ostimer_start(void __iomem *base, bool periodic, u64 cycles)
+{
+	u32 ctrl, load_l;
+
+	load_l = (u32)cycles;
+	ctrl = ((cycles >> 32) & 0xffffff);
+	ctrl |= RDA_OSTIMER_CTRL_LOAD | RDA_OSTIMER_CTRL_ENABLE;
+	if (periodic)
+		ctrl |= RDA_OSTIMER_CTRL_REPEAT;
+
+	/* Enable ostimer interrupt first */
+	writel_relaxed(RDA_TIMER_IRQ_MASK_OSTIMER,
+		       base + RDA_TIMER_IRQ_MASK_SET);
+
+	/* Write low 32 bits first, high 24 bits are with ctrl */
+	writel_relaxed(load_l, base + RDA_OSTIMER_LOADVAL_L);
+	writel_relaxed(ctrl, base + RDA_OSTIMER_CTRL);
+
+	return 0;
+}
+
+static int rda_ostimer_stop(void __iomem *base)
+{
+	/* Disable ostimer interrupt first */
+	writel_relaxed(RDA_TIMER_IRQ_MASK_OSTIMER,
+		       base + RDA_TIMER_IRQ_MASK_CLR);
+
+	writel_relaxed(0, base + RDA_OSTIMER_CTRL);
+
+	return 0;
+}
+
+static int rda_ostimer_set_state_shutdown(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+
+	rda_ostimer_stop(timer_of_base(to));
+
+	return 0;
+}
+
+static int rda_ostimer_set_state_oneshot(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+
+	rda_ostimer_stop(timer_of_base(to));
+
+	return 0;
+}
+
+static int rda_ostimer_set_state_periodic(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+	unsigned long cycles_per_jiffy;
+
+	rda_ostimer_stop(timer_of_base(to));
+
+	cycles_per_jiffy = ((unsigned long long)NSEC_PER_SEC / HZ *
+			     evt->mult) >> evt->shift;
+	rda_ostimer_start(timer_of_base(to), true, cycles_per_jiffy);
+
+	return 0;
+}
+
+static int rda_ostimer_tick_resume(struct clock_event_device *evt)
+{
+	return 0;
+}
+
+static int rda_ostimer_set_next_event(unsigned long evt,
+				      struct clock_event_device *ev)
+{
+	struct timer_of *to = to_timer_of(ev);
+
+	rda_ostimer_start(timer_of_base(to), false, evt);
+
+	return 0;
+}
+
+static irqreturn_t rda_ostimer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+	struct timer_of *to = to_timer_of(evt);
+
+	/* clear timer int */
+	writel_relaxed(RDA_TIMER_IRQ_CLR_OSTIMER,
+		       timer_of_base(to) + RDA_TIMER_IRQ_CLR);
+
+	if (evt->event_handler)
+		evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct timer_of rda_ostimer_of = {
+	.flags = TIMER_OF_IRQ | TIMER_OF_BASE,
+
+	.clkevt = {
+		.name = "rda-ostimer",
+		.rating = 250,
+		.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
+			    CLOCK_EVT_FEAT_DYNIRQ,
+		.set_state_shutdown = rda_ostimer_set_state_shutdown,
+		.set_state_oneshot = rda_ostimer_set_state_oneshot,
+		.set_state_periodic = rda_ostimer_set_state_periodic,
+		.tick_resume = rda_ostimer_tick_resume,
+		.set_next_event	= rda_ostimer_set_next_event,
+	},
+
+	.of_base = {
+		.name = "rda-timer",
+		.index = 0,
+	},
+
+	.of_irq = {
+		.name = "ostimer",
+		.handler = rda_ostimer_interrupt,
+		.flags = IRQF_TIMER,
+	},
+};
+
+static u64 rda_hwtimer_read(struct clocksource *cs)
+{
+	void __iomem *base = timer_of_base(&rda_ostimer_of);
+	u32 lo, hi;
+
+	/* Always read low 32 bits first */
+	do {
+		lo = readl_relaxed(base + RDA_HWTIMER_LOCKVAL_L);
+		hi = readl_relaxed(base + RDA_HWTIMER_LOCKVAL_H);
+	} while (hi != readl_relaxed(base + RDA_HWTIMER_LOCKVAL_H));
+
+	return ((u64)hi << 32) | lo;
+}
+
+static struct clocksource rda_hwtimer_clocksource = {
+	.name           = "rda-timer",
+	.rating         = 400,
+	.read           = rda_hwtimer_read,
+	.mask           = CLOCKSOURCE_MASK(64),
+	.flags          = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int __init rda_timer_init(struct device_node *np)
+{
+	unsigned long rate = 2000000;
+	int ret;
+
+	ret = timer_of_init(np, &rda_ostimer_of);
+	if (ret)
+		return ret;
+
+	clocksource_register_hz(&rda_hwtimer_clocksource, rate);
+
+	clockevents_config_and_register(&rda_ostimer_of.clkevt, rate,
+					0x2, UINT_MAX);
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(rda8810pl, "rda,8810pl-timer", rda_timer_init);

drivers/clocksource/riscv_timer.c → drivers/clocksource/timer-riscv.c

@@ -8,6 +8,7 @@
 #include <linux/cpu.h>
 #include <linux/delay.h>
 #include <linux/irq.h>
+#include <linux/sched_clock.h>
 #include <asm/smp.h>
 #include <asm/sbi.h>
 
@@ -49,6 +50,11 @@ static unsigned long long riscv_clocksource_rdtime(struct clocksource *cs)
 	return get_cycles64();
 }
 
+static u64 riscv_sched_clock(void)
+{
+	return get_cycles64();
+}
+
 static DEFINE_PER_CPU(struct clocksource, riscv_clocksource) = {
 	.name		= "riscv_clocksource",
 	.rating		= 300,
@@ -97,6 +103,9 @@ static int __init riscv_timer_init_dt(struct device_node *n)
 	cs = per_cpu_ptr(&riscv_clocksource, cpuid);
 	clocksource_register_hz(cs, riscv_timebase);
 
+	sched_clock_register(riscv_sched_clock,
+			BITS_PER_LONG, riscv_timebase);
+
 	error = cpuhp_setup_state(CPUHP_AP_RISCV_TIMER_STARTING,
 			 "clockevents/riscv/timer:starting",
 			 riscv_timer_starting_cpu, riscv_timer_dying_cpu);

drivers/clocksource/tegra20_timer.c → drivers/clocksource/timer-tegra20.c

@@ -30,7 +30,6 @@
 #include <linux/delay.h>
 
 #include <asm/mach/time.h>
-#include <asm/smp_twd.h>
 
 #define RTC_SECONDS            0x08
 #define RTC_SHADOW_SECONDS     0x0c

drivers/clocksource/timer-ti-dm.c

@@ -991,7 +991,6 @@ static struct platform_driver omap_dm_timer_driver = {
 	},
 };
 
-early_platform_init("earlytimer", &omap_dm_timer_driver);
 module_platform_driver(omap_dm_timer_driver);
 
 MODULE_DESCRIPTION("OMAP Dual-Mode Timer Driver");

drivers/clocksource/timer-vt8500.c

@@ -145,7 +145,7 @@ static int __init vt8500_timer_init(struct device_node *np)
 
 	ret = clocksource_register_hz(&clocksource, VT8500_TIMER_HZ);
 	if (ret) {
-		pr_err("%s: vt8500_timer_init: clocksource_register failed for %s\n",
+		pr_err("%s: clocksource_register failed for %s\n",
 		       __func__, clocksource.name);
 		return ret;
 	}

include/linux/hrtimer.h

+// SPDX-License-Identifier: GPL-2.0
 /*
- *  include/linux/hrtimer.h
- *
  *  hrtimers - High-resolution kernel timers
  *
  *   Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
@@ -9,8 +8,6 @@
  *  data type definitions, declarations, prototypes
  *
  *  Started by: Thomas Gleixner and Ingo Molnar
- *
- *  For licencing details see kernel-base/COPYING
  */
 #ifndef _LINUX_HRTIMER_H
 #define _LINUX_HRTIMER_H

kernel/time/alarmtimer.c

+// SPDX-License-Identifier: GPL-2.0
 /*
  * Alarmtimer interface
  *
@@ -10,10 +11,6 @@
  * Copyright (C) 2010 IBM Corperation
  *
  * Author: John Stultz <john.stultz@linaro.org>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 #include <linux/time.h>
 #include <linux/hrtimer.h>

kernel/time/clockevents.c

+// SPDX-License-Identifier: GPL-2.0
 /*
- * linux/kernel/time/clockevents.c
- *
  * This file contains functions which manage clock event devices.
  *
  * Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de>
  * Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar
  * Copyright(C) 2006-2007, Timesys Corp., Thomas Gleixner
- *
- * This code is licenced under the GPL version 2. For details see
- * kernel-base/COPYING.
  */
 
 #include <linux/clockchips.h>
@@ -39,10 +35,8 @@ static u64 cev_delta2ns(unsigned long latch, struct clock_event_device *evt,
 	u64 clc = (u64) latch << evt->shift;
 	u64 rnd;
 
-	if (unlikely(!evt->mult)) {
+	if (WARN_ON(!evt->mult))
 		evt->mult = 1;
-		WARN_ON(1);
-	}
 	rnd = (u64) evt->mult - 1;
 
 	/*
@@ -164,10 +158,8 @@ void clockevents_switch_state(struct clock_event_device *dev,
 		 * on it, so fix it up and emit a warning:
 		 */
 		if (clockevent_state_oneshot(dev)) {
-			if (unlikely(!dev->mult)) {
+			if (WARN_ON(!dev->mult))
 				dev->mult = 1;
-				WARN_ON(1);
-			}
 		}
 	}
 }
@@ -315,10 +307,8 @@ int clockevents_program_event(struct clock_event_device *dev, ktime_t expires,
 	int64_t delta;
 	int rc;
 
-	if (unlikely(expires < 0)) {
-		WARN_ON_ONCE(1);
+	if (WARN_ON_ONCE(expires < 0))
 		return -ETIME;
-	}
 
 	dev->next_event = expires;
 

kernel/time/clocksource.c

+// SPDX-License-Identifier: GPL-2.0+
 /*
- * linux/kernel/time/clocksource.c
- *
  * This file contains the functions which manage clocksource drivers.
  *
  * Copyright (C) 2004, 2005 IBM, John Stultz (johnstul@us.ibm.com)
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- * TODO WishList:
- *   o Allow clocksource drivers to be unregistered
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

kernel/time/hrtimer.c

+// SPDX-License-Identifier: GPL-2.0
 /*
- *  linux/kernel/hrtimer.c
- *
  *  Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de>
  *  Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar
  *  Copyright(C) 2006-2007  Timesys Corp., Thomas Gleixner
  *
  *  High-resolution kernel timers
  *
- *  In contrast to the low-resolution timeout API implemented in
- *  kernel/timer.c, hrtimers provide finer resolution and accuracy
- *  depending on system configuration and capabilities.
- *
- *  These timers are currently used for:
- *   - itimers
- *   - POSIX timers
- *   - nanosleep
- *   - precise in-kernel timing
+ *  In contrast to the low-resolution timeout API, aka timer wheel,
+ *  hrtimers provide finer resolution and accuracy depending on system
+ *  configuration and capabilities.
  *
  *  Started by: Thomas Gleixner and Ingo Molnar
  *
  *  Credits:
- *	based on kernel/timer.c
+ *	Based on the original timer wheel code
  *
  *	Help, testing, suggestions, bugfixes, improvements were
  *	provided by:
  *
  *	George Anzinger, Andrew Morton, Steven Rostedt, Roman Zippel
  *	et. al.
- *
- *  For licencing details see kernel-base/COPYING
  */
 
 #include <linux/cpu.h>

kernel/time/itimer.c

 // SPDX-License-Identifier: GPL-2.0
 /*
- * linux/kernel/itimer.c
- *
  * Copyright (C) 1992 Darren Senn
  */
 

kernel/time/jiffies.c

-/***********************************************************************
-* linux/kernel/time/jiffies.c
-*
-* This file contains the jiffies based clocksource.
-*
-* Copyright (C) 2004, 2005 IBM, John Stultz (johnstul@us.ibm.com)
-*
-* This program is free software; you can redistribute it and/or modify
-* it under the terms of the GNU General Public License as published by
-* the Free Software Foundation; either version 2 of the License, or
-* (at your option) any later version.
-*
-* This program is distributed in the hope that it will be useful,
-* but WITHOUT ANY WARRANTY; without even the implied warranty of
-* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-* GNU General Public License for more details.
-*
-* You should have received a copy of the GNU General Public License
-* along with this program; if not, write to the Free Software
-* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-*
-************************************************************************/
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * This file contains the jiffies based clocksource.
+ *
+ * Copyright (C) 2004, 2005 IBM, John Stultz (johnstul@us.ibm.com)
+ */
 #include <linux/clocksource.h>
 #include <linux/jiffies.h>
 #include <linux/module.h>

kernel/time/ntp.c

@@ -17,7 +17,6 @@
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/rtc.h>
-#include <linux/math64.h>
 
 #include "ntp_internal.h"
 #include "timekeeping_internal.h"

kernel/time/posix-clock.c

+// SPDX-License-Identifier: GPL-2.0+
 /*
- * posix-clock.c - support for dynamic clock devices
+ * Support for dynamic clock devices
  *
  * Copyright (C) 2010 OMICRON electronics GmbH
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
- *  (at your option) any later version.
- *
- *  This program is distributed in the hope that it will be useful,
- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  GNU General Public License for more details.
- *
- *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 #include <linux/device.h>
 #include <linux/export.h>

kernel/time/posix-stubs.c

+// SPDX-License-Identifier: GPL-2.0
 /*
  * Dummy stubs used when CONFIG_POSIX_TIMERS=n
  *
  * Created by:  Nicolas Pitre, July 2016
  * Copyright:   (C) 2016 Linaro Limited
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 
 #include <linux/linkage.h>

kernel/time/posix-timers.c

+// SPDX-License-Identifier: GPL-2.0+
 /*
- * linux/kernel/posix-timers.c
- *
- *
  * 2002-10-15  Posix Clocks & timers
  *                           by George Anzinger george@mvista.com
- *
  *			     Copyright (C) 2002 2003 by MontaVista Software.
  *
  * 2004-06-01  Fix CLOCK_REALTIME clock/timer TIMER_ABSTIME bug.
  *			     Copyright (C) 2004 Boris Hu
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or (at
- * your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
-
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- * MontaVista Software | 1237 East Arques Avenue | Sunnyvale | CA 94085 | USA
- */
-
-/* These are all the functions necessary to implement
- * POSIX clocks & timers
+ * These are all the functions necessary to implement POSIX clocks & timers
  */
 #include <linux/mm.h>
 #include <linux/interrupt.h>

kernel/time/sched_clock.c

+// SPDX-License-Identifier: GPL-2.0
 /*
- * sched_clock.c: Generic sched_clock() support, to extend low level
- *                hardware time counters to full 64-bit ns values.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * Generic sched_clock() support, to extend low level hardware time
+ * counters to full 64-bit ns values.
  */
 #include <linux/clocksource.h>
 #include <linux/init.h>

kernel/time/test_udelay.c

+// SPDX-License-Identifier: GPL-2.0
 /*
  * udelay() test kernel module
  *
@@ -7,15 +8,6 @@
  * Specifying usecs of 0 or negative values will run multiples tests.
  *
  * Copyright (C) 2014 Google, Inc.
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
  */
 
 #include <linux/debugfs.h>

kernel/time/tick-broadcast-hrtimer.c

 // SPDX-License-Identifier: GPL-2.0
 /*
- * linux/kernel/time/tick-broadcast-hrtimer.c
- * This file emulates a local clock event device
- * via a pseudo clock device.
+ * Emulate a local clock event device via a pseudo clock device.
  */
 #include <linux/cpu.h>
 #include <linux/err.h>

kernel/time/tick-broadcast.c

+// SPDX-License-Identifier: GPL-2.0
 /*
- * linux/kernel/time/tick-broadcast.c
- *
  * This file contains functions which emulate a local clock-event
  * device via a broadcast event source.
  *
  * Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de>
  * Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar
  * Copyright(C) 2006-2007, Timesys Corp., Thomas Gleixner
- *
- * This code is licenced under the GPL version 2. For details see
- * kernel-base/COPYING.
  */
 #include <linux/cpu.h>
 #include <linux/err.h>

kernel/time/tick-common.c

+// SPDX-License-Identifier: GPL-2.0
 /*
- * linux/kernel/time/tick-common.c
- *
  * This file contains the base functions to manage periodic tick
  * related events.
  *
  * Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de>
  * Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar
  * Copyright(C) 2006-2007, Timesys Corp., Thomas Gleixner
- *
- * This code is licenced under the GPL version 2. For details see
- * kernel-base/COPYING.
  */
 #include <linux/cpu.h>
 #include <linux/err.h>

kernel/time/tick-oneshot.c

+// SPDX-License-Identifier: GPL-2.0
 /*
- * linux/kernel/time/tick-oneshot.c
- *
  * This file contains functions which manage high resolution tick
  * related events.
  *
  * Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de>
  * Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar
  * Copyright(C) 2006-2007, Timesys Corp., Thomas Gleixner
- *
- * This code is licenced under the GPL version 2. For details see
- * kernel-base/COPYING.
  */
 #include <linux/cpu.h>
 #include <linux/err.h>

kernel/time/tick-sched.c

+// SPDX-License-Identifier: GPL-2.0
 /*
- *  linux/kernel/time/tick-sched.c
- *
  *  Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de>
  *  Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar
  *  Copyright(C) 2006-2007  Timesys Corp., Thomas Gleixner
@@ -8,8 +7,6 @@
  *  No idle tick implementation for low and high resolution timers
  *
  *  Started by: Thomas Gleixner and Ingo Molnar
- *
- *  Distribute under GPLv2.
  */
 #include <linux/cpu.h>
 #include <linux/err.h>

kernel/time/time.c

+// SPDX-License-Identifier: GPL-2.0
 /*
- *  linux/kernel/time.c
- *
  *  Copyright (C) 1991, 1992  Linus Torvalds
  *
- *  This file contains the interface functions for the various
- *  time related system calls: time, stime, gettimeofday, settimeofday,
- *			       adjtime
- */
-/*
- * Modification history kernel/time.c
+ *  This file contains the interface functions for the various time related
+ *  system calls: time, stime, gettimeofday, settimeofday, adjtime
+ *
+ * Modification history:
  *
  * 1993-09-02    Philip Gladstone
  *      Created file with time related functions from sched/core.c and adjtimex()

kernel/time/timeconst.bc

+/* SPDX-License-Identifier: GPL-2.0 */
+
 scale=0
 
 define gcd(a,b) {

kernel/time/timeconv.c

+// SPDX-License-Identifier: LGPL-2.0+
 /*
  * Copyright (C) 1993, 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
  * This file is part of the GNU C Library.

kernel/time/timecounter.c

+// SPDX-License-Identifier: GPL-2.0+
 /*
- * linux/kernel/time/timecounter.c
- *
- * based on code that migrated away from
- * linux/kernel/time/clocksource.c
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
+ * Based on clocksource code. See commit 74d23cc704d1
  */
-
 #include <linux/export.h>
 #include <linux/timecounter.h>
 

kernel/time/timekeeping.c

+// SPDX-License-Identifier: GPL-2.0
 /*
- *  linux/kernel/time/timekeeping.c
- *
- *  Kernel timekeeping code and accessor functions
- *
- *  This code was moved from linux/kernel/timer.c.
- *  Please see that file for copyright and history logs.
- *
+ *  Kernel timekeeping code and accessor functions. Based on code from
+ *  timer.c, moved in commit 8524070b7982.
  */
-
 #include <linux/timekeeper_internal.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
@@ -50,7 +45,9 @@ enum timekeeping_adv_mode {
 static struct {
 	seqcount_t		seq;
 	struct timekeeper	timekeeper;
-} tk_core ____cacheline_aligned;
+} tk_core ____cacheline_aligned = {
+	.seq = SEQCNT_ZERO(tk_core.seq),
+};
 
 static DEFINE_RAW_SPINLOCK(timekeeper_lock);
 static struct timekeeper shadow_timekeeper;

kernel/time/timekeeping_debug.c

+// SPDX-License-Identifier: GPL-2.0+
 /*
  * debugfs file to track time spent in suspend
  *
  * Copyright (c) 2011, Google, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
  */
 
 #include <linux/debugfs.h>
@@ -28,7 +19,7 @@
 
 static unsigned int sleep_time_bin[NUM_BINS] = {0};
 
-static int tk_debug_show_sleep_time(struct seq_file *s, void *data)
+static int tk_debug_sleep_time_show(struct seq_file *s, void *data)
 {
 	unsigned int bin;
 	seq_puts(s, "      time (secs)        count\n");
@@ -42,18 +33,7 @@ static int tk_debug_show_sleep_time(struct seq_file *s, void *data)
 	}
 	return 0;
 }
-
-static int tk_debug_sleep_time_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, tk_debug_show_sleep_time, NULL);
-}
-
-static const struct file_operations tk_debug_sleep_time_fops = {
-	.open		= tk_debug_sleep_time_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
+DEFINE_SHOW_ATTRIBUTE(tk_debug_sleep_time);
 
 static int __init tk_debug_sleep_time_init(void)
 {

kernel/time/timer.c

+// SPDX-License-Identifier: GPL-2.0
 /*
- *  linux/kernel/timer.c
- *
  *  Kernel internal timers
  *
  *  Copyright (C) 1991, 1992  Linus Torvalds

kernel/time/timer_list.c

+// SPDX-License-Identifier: GPL-2.0
 /*
- * kernel/time/timer_list.c
- *
  * List pending timers
  *
  * Copyright(C) 2006, Red Hat, Inc., Ingo Molnar
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 
 #include <linux/proc_fs.h>