A set of updates for clocksource and clockevent drivers:

- A fix for the prescaler of the ARM global timer where the prescaler
     mask define only covered 4 bits while it is actully 8 bits wide. This
     restricted obviously the possible range of the prescaler adjustments.
 
   - A fix for the RISC-V timer which prevents a timer interrupt being
     raised while the timer is initialized.
 
   - A set of device tree updates to support new system on chips in various
     drivers.
 
   - Kernel-doc and other cleanups all over the place.
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Merge tag 'timers-core-2024-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull more clocksource updates from Thomas Gleixner:
 "A set of updates for clocksource and clockevent drivers:

   - A fix for the prescaler of the ARM global timer where the prescaler
     mask define only covered 4 bits while it is actully 8 bits wide.
     This obviously restricted the possible range of prescaler
     adjustments

   - A fix for the RISC-V timer which prevents a timer interrupt being
     raised while the timer is initialized

   - A set of device tree updates to support new system on chips in
     various drivers

   - Kernel-doc and other cleanups all over the place"

* tag 'timers-core-2024-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource/drivers/timer-riscv: Clear timer interrupt on timer initialization
  dt-bindings: timer: Add support for cadence TTC PWM
  clocksource/drivers/arm_global_timer: Simplify prescaler register access
  clocksource/drivers/arm_global_timer: Guard against division by zero
  clocksource/drivers/arm_global_timer: Make gt_target_rate unsigned long
  dt-bindings: timer: add Ralink SoCs system tick counter
  clocksource: arm_global_timer: fix non-kernel-doc comment
  clocksource/drivers/arm_global_timer: Remove stray tab
  clocksource/drivers/arm_global_timer: Fix maximum prescaler value
  clocksource/drivers/imx-sysctr: Add i.MX95 support
  clocksource/drivers/imx-sysctr: Drop use global variables
  dt-bindings: timer: nxp,sysctr-timer: support i.MX95
  dt-bindings: timer: renesas: ostm: Document RZ/Five SoC
  dt-bindings: timer: renesas,tmu: Document input capture interrupt
  clocksource/drivers/ti-32K: Fix misuse of "/**" comment
  clocksource/drivers/stm32: Fix all kernel-doc warnings
  dt-bindings: timer: exynos4210-mct: Add google,gs101-mct compatible
  clocksource/drivers/imx: Fix -Wunused-but-set-variable warning

Documentation/devicetree/bindings/timer/cdns,ttc.yaml

@@ -32,12 +32,23 @@ properties:
     description: |
       Bit width of the timer, necessary if not 16.
 
+  "#pwm-cells":
+    const: 3
+
 required:
   - compatible
   - reg
-  - interrupts
   - clocks
 
+allOf:
+  - if:
+      not:
+        required:
+          - "#pwm-cells"
+    then:
+      required:
+        - interrupts
+
 additionalProperties: false
 
 examples:
@@ -50,3 +61,12 @@ examples:
         clocks = <&cpu_clk 3>;
         timer-width = <32>;
     };
+
+  - |
+    pwm: pwm@f8002000 {
+        compatible = "cdns,ttc";
+        reg = <0xf8002000 0x1000>;
+        clocks = <&cpu_clk 3>;
+        timer-width = <32>;
+        #pwm-cells = <3>;
+    };

Documentation/devicetree/bindings/timer/nxp,sysctr-timer.yaml

@@ -18,7 +18,9 @@ description: |
 
 properties:
   compatible:
-    const: nxp,sysctr-timer
+    enum:
+      - nxp,imx95-sysctr-timer
+      - nxp,sysctr-timer
 
   reg:
     maxItems: 1

Documentation/devicetree/bindings/timer/ralink,cevt-systick.yaml

@@ -0,0 +1,38 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/timer/ralink,cevt-systick.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: System tick counter present in Ralink family SoCs
+
+maintainers:
+  - Sergio Paracuellos <sergio.paracuellos@gmail.com>
+
+properties:
+  compatible:
+    const: ralink,cevt-systick
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    systick@d00 {
+        compatible = "ralink,cevt-systick";
+        reg = <0xd00 0x10>;
+
+        interrupt-parent = <&cpuintc>;
+        interrupts = <7>;
+    };
+...

Documentation/devicetree/bindings/timer/renesas,ostm.yaml

@@ -23,7 +23,7 @@ properties:
       - enum:
           - renesas,r7s72100-ostm  # RZ/A1H
           - renesas,r7s9210-ostm   # RZ/A2M
-          - renesas,r9a07g043-ostm # RZ/G2UL
+          - renesas,r9a07g043-ostm # RZ/G2UL and RZ/Five
           - renesas,r9a07g044-ostm # RZ/G2{L,LC}
           - renesas,r9a07g054-ostm # RZ/V2L
       - const: renesas,ostm        # Generic

Documentation/devicetree/bindings/timer/renesas,tmu.yaml

@@ -46,7 +46,19 @@ properties:
 
   interrupts:
     minItems: 2
-    maxItems: 3
+    items:
+      - description: Underflow interrupt, channel 0
+      - description: Underflow interrupt, channel 1
+      - description: Underflow interrupt, channel 2
+      - description: Input capture interrupt, channel 2
+
+  interrupt-names:
+    minItems: 2
+    items:
+      - const: tuni0
+      - const: tuni1
+      - const: tuni2
+      - const: ticpi2
 
   clocks:
     maxItems: 1
@@ -100,7 +112,9 @@ examples:
             reg = <0xffd80000 0x30>;
             interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>,
                          <GIC_SPI 33 IRQ_TYPE_LEVEL_HIGH>,
-                         <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
+                         <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>,
+                         <GIC_SPI 35 IRQ_TYPE_LEVEL_HIGH>;
+            interrupt-names = "tuni0", "tuni1", "tuni2", "ticpi2";
             clocks = <&mstp0_clks R8A7779_CLK_TMU0>;
             clock-names = "fck";
             power-domains = <&sysc R8A7779_PD_ALWAYS_ON>;

Documentation/devicetree/bindings/timer/samsung,exynos4210-mct.yaml

@@ -26,6 +26,7 @@ properties:
       - items:
           - enum:
               - axis,artpec8-mct
+              - google,gs101-mct
               - samsung,exynos3250-mct
               - samsung,exynos5250-mct
               - samsung,exynos5260-mct
@@ -127,6 +128,7 @@ allOf:
           contains:
             enum:
               - axis,artpec8-mct
+              - google,gs101-mct
               - samsung,exynos5260-mct
               - samsung,exynos5420-mct
               - samsung,exynos5433-mct

drivers/clocksource/arm_global_timer.c

@@ -9,6 +9,7 @@
 
 #include <linux/init.h>
 #include <linux/interrupt.h>
+#include <linux/bitfield.h>
 #include <linux/clocksource.h>
 #include <linux/clockchips.h>
 #include <linux/cpu.h>
@@ -31,10 +32,7 @@
 #define GT_CONTROL_COMP_ENABLE		BIT(1)	/* banked */
 #define GT_CONTROL_IRQ_ENABLE		BIT(2)	/* banked */
 #define GT_CONTROL_AUTO_INC		BIT(3)	/* banked */
-#define GT_CONTROL_PRESCALER_SHIFT      8
+#define GT_CONTROL_PRESCALER_MASK	GENMASK(15, 8)
-#define GT_CONTROL_PRESCALER_MAX        0xF
-#define GT_CONTROL_PRESCALER_MASK       (GT_CONTROL_PRESCALER_MAX << \
-					 GT_CONTROL_PRESCALER_SHIFT)
 
 #define GT_INT_STATUS	0x0c
 #define GT_INT_STATUS_EVENT_FLAG	BIT(0)
@@ -52,7 +50,8 @@
  */
 static void __iomem *gt_base;
 static struct notifier_block gt_clk_rate_change_nb;
-static u32 gt_psv_new, gt_psv_bck, gt_target_rate;
+static u32 gt_psv_new, gt_psv_bck;
+static unsigned long gt_target_rate;
 static int gt_ppi;
 static struct clock_event_device __percpu *gt_evt;
 
@@ -88,7 +87,7 @@ static u64 gt_counter_read(void)
 	return _gt_counter_read();
 }
 
-/**
+/*
  * To ensure that updates to comparator value register do not set the
  * Interrupt Status Register proceed as follows:
  * 1. Clear the Comp Enable bit in the Timer Control Register.
@@ -247,7 +246,7 @@ static void gt_write_presc(u32 psv)
 
 	reg = readl(gt_base + GT_CONTROL);
 	reg &= ~GT_CONTROL_PRESCALER_MASK;
-	reg |= psv << GT_CONTROL_PRESCALER_SHIFT;
+	reg |= FIELD_PREP(GT_CONTROL_PRESCALER_MASK, psv);
 	writel(reg, gt_base + GT_CONTROL);
 }
 
@@ -256,8 +255,7 @@ static u32 gt_read_presc(void)
 	u32 reg;
 
 	reg = readl(gt_base + GT_CONTROL);
-	reg &= GT_CONTROL_PRESCALER_MASK;
+	return FIELD_GET(GT_CONTROL_PRESCALER_MASK, reg);
-	return reg >> GT_CONTROL_PRESCALER_SHIFT;
 }
 
 static void __init gt_delay_timer_init(void)
@@ -272,9 +270,9 @@ static int __init gt_clocksource_init(void)
 	writel(0, gt_base + GT_COUNTER0);
 	writel(0, gt_base + GT_COUNTER1);
 	/* set prescaler and enable timer on all the cores */
-	writel(((CONFIG_ARM_GT_INITIAL_PRESCALER_VAL - 1) <<
+	writel(FIELD_PREP(GT_CONTROL_PRESCALER_MASK,
-		GT_CONTROL_PRESCALER_SHIFT)
+			  CONFIG_ARM_GT_INITIAL_PRESCALER_VAL - 1) |
-	       | GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL);
+	       GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL);
 
 #ifdef CONFIG_CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
 	sched_clock_register(gt_sched_clock_read, 64, gt_target_rate);
@@ -290,18 +288,17 @@ static int gt_clk_rate_change_cb(struct notifier_block *nb,
 	switch (event) {
 	case PRE_RATE_CHANGE:
 	{
-		int psv;
+		unsigned long psv;
 
-		psv = DIV_ROUND_CLOSEST(ndata->new_rate,
+		psv = DIV_ROUND_CLOSEST(ndata->new_rate, gt_target_rate);
-					gt_target_rate);
+		if (!psv ||
-
+		    abs(gt_target_rate - (ndata->new_rate / psv)) > MAX_F_ERR)
-		if (abs(gt_target_rate - (ndata->new_rate / psv)) > MAX_F_ERR)
 			return NOTIFY_BAD;
 
 		psv--;
 
 		/* prescaler within legal range? */
-		if (psv < 0 || psv > GT_CONTROL_PRESCALER_MAX)
+		if (!FIELD_FIT(GT_CONTROL_PRESCALER_MASK, psv))
 			return NOTIFY_BAD;
 
 		/*

drivers/clocksource/timer-imx-gpt.c

@@ -258,9 +258,8 @@ static irqreturn_t mxc_timer_interrupt(int irq, void *dev_id)
 {
 	struct clock_event_device *ced = dev_id;
 	struct imx_timer *imxtm = to_imx_timer(ced);
-	uint32_t tstat;
 
-	tstat = readl_relaxed(imxtm->base + imxtm->gpt->reg_tstat);
+	readl_relaxed(imxtm->base + imxtm->gpt->reg_tstat);
 
 	imxtm->gpt->gpt_irq_acknowledge(imxtm);
 

drivers/clocksource/timer-imx-sysctr.c

@@ -4,48 +4,62 @@
 
 #include <linux/interrupt.h>
 #include <linux/clockchips.h>
+#include <linux/slab.h>
 
 #include "timer-of.h"
 
 #define CMP_OFFSET	0x10000
+#define RD_OFFSET	0x20000
 
 #define CNTCV_LO	0x8
 #define CNTCV_HI	0xc
 #define CMPCV_LO	(CMP_OFFSET + 0x20)
 #define CMPCV_HI	(CMP_OFFSET + 0x24)
 #define CMPCR		(CMP_OFFSET + 0x2c)
+#define CNTCV_LO_IMX95	(RD_OFFSET + 0x8)
+#define CNTCV_HI_IMX95	(RD_OFFSET + 0xc)
 
 #define SYS_CTR_EN		0x1
 #define SYS_CTR_IRQ_MASK	0x2
 
 #define SYS_CTR_CLK_DIV		0x3
 
-static void __iomem *sys_ctr_base __ro_after_init;
+struct sysctr_private {
-static u32 cmpcr __ro_after_init;
+	u32 cmpcr;
+	u32 lo_off;
+	u32 hi_off;
+};
 
-static void sysctr_timer_enable(bool enable)
+static void sysctr_timer_enable(struct clock_event_device *evt, bool enable)
 {
-	writel(enable ? cmpcr | SYS_CTR_EN : cmpcr, sys_ctr_base + CMPCR);
+	struct timer_of *to = to_timer_of(evt);
+	struct sysctr_private *priv = to->private_data;
+	void __iomem *base = timer_of_base(to);
+
+	writel(enable ? priv->cmpcr | SYS_CTR_EN : priv->cmpcr, base + CMPCR);
 }
 
-static void sysctr_irq_acknowledge(void)
+static void sysctr_irq_acknowledge(struct clock_event_device *evt)
 {
 	/*
 	 * clear the enable bit(EN =0) will clear
 	 * the status bit(ISTAT = 0), then the interrupt
 	 * signal will be negated(acknowledged).
 	 */
-	sysctr_timer_enable(false);
+	sysctr_timer_enable(evt, false);
 }
 
-static inline u64 sysctr_read_counter(void)
+static inline u64 sysctr_read_counter(struct clock_event_device *evt)
 {
+	struct timer_of *to = to_timer_of(evt);
+	struct sysctr_private *priv = to->private_data;
+	void __iomem *base = timer_of_base(to);
 	u32 cnt_hi, tmp_hi, cnt_lo;
 
 	do {
-		cnt_hi = readl_relaxed(sys_ctr_base + CNTCV_HI);
+		cnt_hi = readl_relaxed(base + priv->hi_off);
-		cnt_lo = readl_relaxed(sys_ctr_base + CNTCV_LO);
+		cnt_lo = readl_relaxed(base + priv->lo_off);
-		tmp_hi = readl_relaxed(sys_ctr_base + CNTCV_HI);
+		tmp_hi = readl_relaxed(base + priv->hi_off);
 	} while (tmp_hi != cnt_hi);
 
 	return  ((u64) cnt_hi << 32) | cnt_lo;
@@ -54,22 +68,24 @@ static inline u64 sysctr_read_counter(void)
 static int sysctr_set_next_event(unsigned long delta,
 				 struct clock_event_device *evt)
 {
+	struct timer_of *to = to_timer_of(evt);
+	void __iomem *base = timer_of_base(to);
 	u32 cmp_hi, cmp_lo;
 	u64 next;
 
-	sysctr_timer_enable(false);
+	sysctr_timer_enable(evt, false);
 
-	next = sysctr_read_counter();
+	next = sysctr_read_counter(evt);
 
 	next += delta;
 
 	cmp_hi = (next >> 32) & 0x00fffff;
 	cmp_lo = next & 0xffffffff;
 
-	writel_relaxed(cmp_hi, sys_ctr_base + CMPCV_HI);
+	writel_relaxed(cmp_hi, base + CMPCV_HI);
-	writel_relaxed(cmp_lo, sys_ctr_base + CMPCV_LO);
+	writel_relaxed(cmp_lo, base + CMPCV_LO);
 
-	sysctr_timer_enable(true);
+	sysctr_timer_enable(evt, true);
 
 	return 0;
 }
@@ -81,7 +97,7 @@ static int sysctr_set_state_oneshot(struct clock_event_device *evt)
 
 static int sysctr_set_state_shutdown(struct clock_event_device *evt)
 {
-	sysctr_timer_enable(false);
+	sysctr_timer_enable(evt, false);
 
 	return 0;
 }
@@ -90,7 +106,7 @@ static irqreturn_t sysctr_timer_interrupt(int irq, void *dev_id)
 {
 	struct clock_event_device *evt = dev_id;
 
-	sysctr_irq_acknowledge();
+	sysctr_irq_acknowledge(evt);
 
 	evt->event_handler(evt);
 
@@ -117,34 +133,75 @@ static struct timer_of to_sysctr = {
 	},
 };
 
-static void __init sysctr_clockevent_init(void)
+static int __init __sysctr_timer_init(struct device_node *np)
 {
-	to_sysctr.clkevt.cpumask = cpu_possible_mask;
+	struct sysctr_private *priv;
+	void __iomem *base;
+	int ret;
 
-	clockevents_config_and_register(&to_sysctr.clkevt,
+	priv = kzalloc(sizeof(struct sysctr_private), GFP_KERNEL);
-					timer_of_rate(&to_sysctr),
+	if (!priv)
-					0xff, 0x7fffffff);
+		return -ENOMEM;
-}
-
-static int __init sysctr_timer_init(struct device_node *np)
-{
-	int ret = 0;
 
 	ret = timer_of_init(np, &to_sysctr);
-	if (ret)
+	if (ret) {
+		kfree(priv);
 		return ret;
+	}
 
 	if (!of_property_read_bool(np, "nxp,no-divider")) {
 		/* system counter clock is divided by 3 internally */
 		to_sysctr.of_clk.rate /= SYS_CTR_CLK_DIV;
 	}
 
-	sys_ctr_base = timer_of_base(&to_sysctr);
+	to_sysctr.clkevt.cpumask = cpu_possible_mask;
-	cmpcr = readl(sys_ctr_base + CMPCR);
+	to_sysctr.private_data = priv;
-	cmpcr &= ~SYS_CTR_EN;
 
-	sysctr_clockevent_init();
+	base = timer_of_base(&to_sysctr);
+	priv->cmpcr = readl(base + CMPCR) & ~SYS_CTR_EN;
 
 	return 0;
 }
+
+static int __init sysctr_timer_init(struct device_node *np)
+{
+	struct sysctr_private *priv;
+	int ret;
+
+	ret = __sysctr_timer_init(np);
+	if (ret)
+		return ret;
+
+	priv = to_sysctr.private_data;
+	priv->lo_off = CNTCV_LO;
+	priv->hi_off = CNTCV_HI;
+
+	clockevents_config_and_register(&to_sysctr.clkevt,
+					timer_of_rate(&to_sysctr),
+					0xff, 0x7fffffff);
+
+	return 0;
+}
+
+static int __init sysctr_timer_imx95_init(struct device_node *np)
+{
+	struct sysctr_private *priv;
+	int ret;
+
+	ret = __sysctr_timer_init(np);
+	if (ret)
+		return ret;
+
+	priv = to_sysctr.private_data;
+	priv->lo_off = CNTCV_LO_IMX95;
+	priv->hi_off = CNTCV_HI_IMX95;
+
+	clockevents_config_and_register(&to_sysctr.clkevt,
+					timer_of_rate(&to_sysctr),
+					0xff, 0x7fffffff);
+
+	return 0;
+}
+
 TIMER_OF_DECLARE(sysctr_timer, "nxp,sysctr-timer", sysctr_timer_init);
+TIMER_OF_DECLARE(sysctr_timer_imx95, "nxp,imx95-sysctr-timer", sysctr_timer_imx95_init);

drivers/clocksource/timer-riscv.c

@@ -108,6 +108,9 @@ static int riscv_timer_starting_cpu(unsigned int cpu)
 {
 	struct clock_event_device *ce = per_cpu_ptr(&riscv_clock_event, cpu);
 
+	/* Clear timer interrupt */
+	riscv_clock_event_stop();
+
 	ce->cpumask = cpumask_of(cpu);
 	ce->irq = riscv_clock_event_irq;
 	if (riscv_timer_cannot_wake_cpu)

drivers/clocksource/timer-stm32.c

@@ -73,7 +73,7 @@ static void stm32_timer_of_bits_set(struct timer_of *to, int bits)
  * Accessor helper to get the number of bits in the timer-of private
  * structure.
  *
- * Returns an integer corresponding to the number of bits.
+ * Returns: an integer corresponding to the number of bits.
  */
 static int stm32_timer_of_bits_get(struct timer_of *to)
 {
@@ -177,7 +177,7 @@ static irqreturn_t stm32_clock_event_handler(int irq, void *dev_id)
 }
 
 /**
- * stm32_timer_width - Sort out the timer width (32/16)
+ * stm32_timer_set_width - Sort out the timer width (32/16)
  * @to: a pointer to a timer-of structure
  *
  * Write the 32-bit max value and read/return the result. If the timer

drivers/clocksource/timer-ti-32k.c

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-only
-/**
+/*
  * timer-ti-32k.c - OMAP2 32k Timer Support
  *
  * Copyright (C) 2009 Nokia Corporation