From nobody Wed Apr 1 11:13:16 2026 Received: from smtpout-03.galae.net (smtpout-03.galae.net [185.246.85.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E79A540B6F2 for ; Tue, 31 Mar 2026 15:26:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.246.85.4 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774970793; cv=none; b=a7bw6IgK/Ix27kfIibFZtvl0aowIb+yIfGZeb6ORJ8AbSlOqBvx4AnS+5rgoHn/LWFlcujCWuK+8qNAHXcNSEZnDLr6LjVk2nRGQGNHD11MJcS0u6EzTS0dOmiTUE7Ck/Y9T3l4aBAyd7E8rFxm48Zsi6EvkT6C8vmAucp+TqPE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774970793; c=relaxed/simple; bh=68jz09bkdX5VCBt3lhHifrcT2xDbugxcG1OphrZl0yQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=TyMexj0ka5bmY/vRMPR0jG1djy/aTQn4F3F2ESZPNeFGi77b1MJiIwEC4/ho1IdmuU4584CRnHq3WBwsGWZKouSYE/MorV5sLyH9mqROuCQTETWAglcAkgXRs5wcHrepQOfmgjlGKjP7TIALKsFBkLlBXQ/KLQ02x5YvbHJQ2PA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=p7kaJrVU; arc=none smtp.client-ip=185.246.85.4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="p7kaJrVU" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-03.galae.net (Postfix) with ESMTPS id 2D9E94E4288A; Tue, 31 Mar 2026 15:26:28 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id F060E6029D; Tue, 31 Mar 2026 15:26:27 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 75D6F10450349; Tue, 31 Mar 2026 17:26:25 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1774970787; h=from:subject:date:message-id:to:cc:mime-version: content-transfer-encoding:in-reply-to:references; bh=Bf9vVyYNNyHX0sd0tzX+my/IB3kLEr65JMLXf+rZwuQ=; b=p7kaJrVUih7smTw83SindBiczPSy/Ank0GBZ4Obo53gphftpQNQf0HbeLTuyYYDWHyapG+ FbX2zFRjFT9OVItsUpjvcG1NZ6bMtKvQ6dfFyhPr4JvSqSd+GLkJTfx6jHQUCPCeTrjCC8 Zkus3c2r7GaJqbDrZQrdfg+IgY+ntpbE9daViCwTw94RrJQQzPNInopHz64PVCKybcfdRX jo9BzHNGUGB1glgW89kprnUHgKfw3nF2khDJ/K134BNxvBdlcxWOp4xnVZLQk3JwULNhHr P1AScABeCpLNeLKcH7riyOlDP8ar+jxnvhmxjPLSGa+uLxnD9owDzHKsmog+bw== From: "Herve Codina (Schneider Electric)" To: Wolfram Sang , Herve Codina , Daniel Lezcano , Thomas Gleixner , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Geert Uytterhoeven , Magnus Damm Cc: linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Pascal Eberhard , Miquel Raynal , Thomas Petazzoni Subject: [PATCH 2/4] clocksource/drivers: Add support for the Renesas RZ/N1 timers Date: Tue, 31 Mar 2026 17:26:13 +0200 Message-ID: <20260331152616.197031-3-herve.codina@bootlin.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260331152616.197031-1-herve.codina@bootlin.com> References: <20260331152616.197031-1-herve.codina@bootlin.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Last-TLS-Session-Version: TLSv1.3 Content-Type: text/plain; charset="utf-8" The Renesas RZ/N1 timer block controller is the controller in charge of timers available in the Renesas RZ/N1 SoCs family. This controller handles 8 timers: - 6 16-bit timers - 2 32-bit timers Each timer has its own interrupt, its own prescaler that can be used to device the clock by 25 and all of them can work in either one-shot or periodic mode. Signed-off-by: Herve Codina (Schneider Electric) --- drivers/clocksource/Kconfig | 10 + drivers/clocksource/Makefile | 1 + drivers/clocksource/timer-rzn1.c | 442 +++++++++++++++++++++++++++++++ 3 files changed, 453 insertions(+) create mode 100644 drivers/clocksource/timer-rzn1.c diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index fd9112706545..31cf40880ece 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -152,6 +152,16 @@ config REALTEK_OTTO_TIMER RT8391, RTL8392, RTL8393 and RTL8396 and chips of the RTL930x series such as RTL9301, RTL9302 or RTL9303. =20 +config RZN1_TIMER + bool "Renesas RZ/N1 Timer" + depends on HAS_IOMEM && COMMON_CLK && (ARCH_RZN1 || COMPILE_TEST) + help + Enables support for RZ/N1 SoC timers. + A timers block in RZ/N1 SoCs is composed of 8 timers + - 6 16-bit timers + - 2 32-bit timers + Two timers blocks are available in RZ/N1 SoCs. + config SUN4I_TIMER bool "Sun4i timer driver" if COMPILE_TEST depends on HAS_IOMEM diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index b46376af6b49..464ec6690ab6 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -96,3 +96,4 @@ obj-$(CONFIG_EP93XX_TIMER) +=3D timer-ep93xx.o obj-$(CONFIG_RALINK_TIMER) +=3D timer-ralink.o obj-$(CONFIG_NXP_STM_TIMER) +=3D timer-nxp-stm.o obj-$(CONFIG_RTK_SYSTIMER) +=3D timer-realtek.o +obj-$(CONFIG_RZN1_TIMER) +=3D timer-rzn1.o diff --git a/drivers/clocksource/timer-rzn1.c b/drivers/clocksource/timer-r= zn1.c new file mode 100644 index 000000000000..1b95b0b5cd3b --- /dev/null +++ b/drivers/clocksource/timer-rzn1.c @@ -0,0 +1,442 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * RZ/N1 timers driver + * + * Copyright (C) 2026 Schneider-Electric + * + * Author: Herve Codina + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Per-timer register offsets */ +#define RZN1_TIMER_LOAD_COUNT_REG 0x00 +#define RZN1_TIMER_CURRENT_COUNT_REG 0x04 +#define RZN1_TIMER_CONTROL_REG 0x08 +#define RZN1_TIMER_CONTROL_INT_UNMASK BIT(3) +#define RZN1_TIMER_CONTROL_ENABLE BIT(2) +#define RZN1_TIMER_CONTROL_AUTORELOAD BIT(1) +#define RZN1_TIMER_CONTROL_PRESCALER_DIV25 BIT(0) +#define RZN1_TIMER_CLEAR_INT_REG 0x0c +#define RZN1_TIMER_STATUS_INT0_REG 0x10 +#define RZN1_TIMER_STATUS_INT1_REG 0x14 + +/* + * 8 timers are available. Among those 8 timers, the first 6 timers are 16= -bit + * timers and the last two ones are 32-bit timers. + */ +#define RZN1_TIMER_BASE_INDEX_16BIT_TIMERS 0 +#define RZN1_TIMER_NB_16BIT_TIMERS 6 + +#define RZN1_TIMER_BASE_INDEX_32BIT_TIMER 6 +#define RZN1_TIMER_NB_32BIT_TIMERS 2 + +#define RZN1_TIMER_IS_16BIT_TIMER(_i) ((_i) < RZN1_TIMER_BASE_INDEX_32BIT_= TIMER) + +/* Total numbers of timers */ +#define RZN1_TIMER_NB_TIMERS (RZN1_TIMER_NB_16BIT_TIMERS + \ + RZN1_TIMER_NB_32BIT_TIMERS) + +/* Offset of registers related to the timer number _i in the timers regs a= rea */ +#define RZN1_TIMER_REGS_OFFSET(_i) (0x20 * (_i)) + +struct rzn1_timer { + void __iomem *base; + unsigned int width; + unsigned long rate; + unsigned long hz_period; + struct clock_event_device ced; +}; + +static int rzn1_timer_config(struct rzn1_timer *timer, u32 period, bool is= _periodic) +{ + u32 ctrl; + + ctrl =3D readl(timer->base + RZN1_TIMER_CONTROL_REG); + + /* Disable the timer */ + writel(ctrl & ~RZN1_TIMER_CONTROL_ENABLE, + timer->base + RZN1_TIMER_CONTROL_REG); + + /* Set the new period */ + writel(period, timer->base + RZN1_TIMER_LOAD_COUNT_REG); + + /* Prepare the timer mode */ + if (is_periodic) + ctrl |=3D RZN1_TIMER_CONTROL_AUTORELOAD; + else + ctrl &=3D ~RZN1_TIMER_CONTROL_AUTORELOAD; + + /* + * Enable the timer. + * + * This automatically resets the CURRENT_COUNT register. + */ + ctrl |=3D RZN1_TIMER_CONTROL_ENABLE; + writel(ctrl, timer->base + RZN1_TIMER_CONTROL_REG); + + return 0; +} + +static void rzn1_timer_disable(struct rzn1_timer *timer) +{ + u32 ctrl; + + ctrl =3D readl(timer->base + RZN1_TIMER_CONTROL_REG); + ctrl &=3D ~RZN1_TIMER_CONTROL_ENABLE; + writel(ctrl, timer->base + RZN1_TIMER_CONTROL_REG); +} + +static void rzn1_timer_int_enable(struct rzn1_timer *timer) +{ + u32 ctrl; + + ctrl =3D readl(timer->base + RZN1_TIMER_CONTROL_REG); + ctrl |=3D RZN1_TIMER_CONTROL_INT_UNMASK; + writel(ctrl, timer->base + RZN1_TIMER_CONTROL_REG); +} + +static irqreturn_t rzn1_timer_interrupt(int irq, void *dev_id) +{ + struct rzn1_timer *timer =3D dev_id; + + /* Ack the interrupt */ + readl(timer->base + RZN1_TIMER_CLEAR_INT_REG); + + timer->ced.event_handler(&timer->ced); + return IRQ_HANDLED; +} + +static int rzn1_clkevt_set_next_event(unsigned long cycles, + struct clock_event_device *evt) +{ + struct rzn1_timer *timer =3D container_of(evt, struct rzn1_timer, ced); + + return rzn1_timer_config(timer, cycles, false); +} + +static int rzn1_clkevt_shutdown(struct clock_event_device *evt) +{ + struct rzn1_timer *timer =3D container_of(evt, struct rzn1_timer, ced); + + rzn1_timer_disable(timer); + return 0; +} + +static int rzn1_clkevt_set_periodic(struct clock_event_device *evt) +{ + struct rzn1_timer *timer =3D container_of(evt, struct rzn1_timer, ced); + + rzn1_timer_config(timer, timer->hz_period, true); + return 0; +} + +/* + * This global lock is used to prevent race conditions during global timers + * test and set operation in case the driver is using the async probe opti= on. + */ +static DEFINE_MUTEX(rzn1_global_timers_lock); + +static int rzn1_timer_instance; + +/* scheduler and clocksource */ +static struct rzn1_timer *rzn1_sched_clock; + +static u64 notrace rzn1_sched_read(void) +{ + return readl_relaxed(rzn1_sched_clock->base + RZN1_TIMER_CURRENT_COUNT_RE= G); +} + +static u64 rzn1_clksrc_read(struct clocksource *cs) +{ + return readl_relaxed(rzn1_sched_clock->base + RZN1_TIMER_CURRENT_COUNT_RE= G); +} + +static struct clocksource rzn1_clocksource =3D { + .name =3D "rzn1_timer_clocksource", + .rating =3D 200, + .flags =3D CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_SUSPEND_NONSTOP, + .read =3D rzn1_clksrc_read, +}; + +/* Timers table where 32-bit timers will be assigned per-cpu */ +static struct rzn1_timer *rzn1_tab_timers; + +static int rzn1_local_timer_starting_cpu(unsigned int cpu) +{ + struct rzn1_timer *timer; + + if (cpu > RZN1_TIMER_NB_32BIT_TIMERS) + return -EINVAL; + + timer =3D &rzn1_tab_timers[cpu + RZN1_TIMER_BASE_INDEX_32BIT_TIMER]; + + timer->ced.cpumask =3D cpumask_of(cpu); + irq_force_affinity(timer->ced.irq, cpumask_of(cpu)); + clockevents_config_and_register(&timer->ced, timer->rate, 1, + GENMASK(timer->width - 1, 0)); + + return 0; +} + +static void rzn1_timer_init(struct rzn1_timer *timer, unsigned int index, + void __iomem *timers_base, unsigned long clock_rate) +{ + timer->base =3D timers_base + RZN1_TIMER_REGS_OFFSET(index); + + /* Disable the timer */ + writel(0, timer->base + RZN1_TIMER_CONTROL_REG); + + /* Clear potential interrupts */ + readl(timer->base + RZN1_TIMER_CLEAR_INT_REG); + + if (RZN1_TIMER_IS_16BIT_TIMER(index)) { + timer->width =3D 16; + /* + * Enable pre-scaler for 16-bit timers. + * + * Timers are fed by a 25MHz clock. With this pre-scaler (1/25) + * enabled, the 16-bit timers resolution is 1 microsecond. + */ + writel(RZN1_TIMER_CONTROL_PRESCALER_DIV25, + timer->base + RZN1_TIMER_CONTROL_REG); + timer->rate =3D clock_rate / 25; + } else { + timer->width =3D 32; + timer->rate =3D clock_rate; + } + timer->hz_period =3D DIV_ROUND_UP(timer->rate, HZ); +} + +static void rzn1_timer_clkevt_init_ced(struct rzn1_timer *timer, const cha= r *name, + int irq) +{ + timer->ced.features =3D CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + timer->ced.set_next_event =3D rzn1_clkevt_set_next_event; + timer->ced.set_state_shutdown =3D rzn1_clkevt_shutdown; + timer->ced.set_state_periodic =3D rzn1_clkevt_set_periodic; + timer->ced.cpumask =3D cpu_possible_mask; + + /* + * 32-bit timers are fed with a 25 MHz clock directly derived from the + * main PLL (1 GHz). The arch timer, ARMv7 CP15 in RZ/N1 SoCs, is fed + * with to a 6.25 MHz clock. + * + * The clock of the RZ/N1 timers block is a stable one and the RZ/N1 + * timers have a higher resolution than the ARM CP15 one. + * + * Also those 32-bit RZ/N1 timers are assigned per-cpu. + * + * Use a high rating for the 32-bit RZ/N1 timers in order to have them + * chosen by the system. + */ + timer->ced.rating =3D timer->width =3D=3D 16 ? 200 : 460; + timer->ced.owner =3D THIS_MODULE; + timer->ced.name =3D name; + timer->ced.irq =3D irq; +} + +static int rzn1_timer_probe_first(struct platform_device *pdev, struct rzn= 1_timer *tab_timers, + void __iomem *base, unsigned long clock_rate) +{ + struct device *dev =3D &pdev->dev; + struct rzn1_timer *timer; + unsigned int i; + char *name; + int irq; + int ret; + + /* + * Probe the first instance. In that case, timers are assigned as + * follow: + * - First 16-bit timer: clocksource and sched_clock + * - Other 16-bit timers: clock events for all possible CPUs + * - 32-bit timers: clock events per CPU + * + * First step, perform all operation that could fail without calling + * clockevents_config_and_register(), sched_clock_register() nor + * cpuhp_setup_state(). Those operation don't have unregister nor + * teardown counterparts and so, once called, we cannot remove the + * related resource. + */ + + /* + * First step for 16-bit timers except the first one and all 32-bit + * timers. + */ + for (i =3D RZN1_TIMER_BASE_INDEX_16BIT_TIMERS + 1; i < RZN1_TIMER_NB_TIME= RS; i++) { + timer =3D &tab_timers[i]; + + rzn1_timer_init(timer, i, base, clock_rate); + + irq =3D platform_get_irq(pdev, i); + if (irq < 0) + return irq; + + name =3D devm_kasprintf(dev, GFP_KERNEL, "%s-%u", dev_name(dev), i); + if (!name) + return -ENOMEM; + + rzn1_timer_clkevt_init_ced(timer, name, irq); + + ret =3D devm_request_irq(dev, timer->ced.irq, rzn1_timer_interrupt, + IRQF_TIMER, timer->ced.name, timer); + if (ret < 0) + return dev_err_probe(dev, irq, "timer%d: Failed to request IRQ\n", i); + + rzn1_timer_int_enable(timer); + } + + /* + * Second step, almost all operations that can fail have been called. + * Timers are ready to work. Start with the last operation that can fail, + * installing and invoking hotplug callbacks + */ + rzn1_tab_timers =3D tab_timers; + ret =3D cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, + "clockevents/rzn1/global_timer:starting", + rzn1_local_timer_starting_cpu, NULL); + if (ret < 0) + return dev_err_probe(dev, ret, "Setup CPU hotplug state failed\n"); + + /* + * At this point, no more operations can fail. Perform remaining + * operations. Starting by handling the first 16-bit timer + */ + timer =3D &tab_timers[RZN1_TIMER_BASE_INDEX_16BIT_TIMERS]; + + rzn1_timer_init(timer, RZN1_TIMER_BASE_INDEX_16BIT_TIMERS, base, clock_ra= te); + rzn1_timer_config(timer, GENMASK(timer->width - 1, 0), true); + + rzn1_sched_clock =3D timer; + + sched_clock_register(rzn1_sched_read, rzn1_sched_clock->width, rzn1_sched= _clock->rate); + + rzn1_clocksource.mask =3D CLOCKSOURCE_MASK(rzn1_sched_clock->width); + clocksource_register_hz(&rzn1_clocksource, rzn1_sched_clock->rate); + + /* + * Register clockevents only for 16-bit timers. 32-bit timers clockevents + * are registered by CPU hotplug startup function set previously by the + * cpuhp_setup_state() call. + */ + for (i =3D RZN1_TIMER_BASE_INDEX_16BIT_TIMERS + 1; i < RZN1_TIMER_NB_16BI= T_TIMERS; i++) { + timer =3D &tab_timers[i]; + clockevents_config_and_register(&timer->ced, timer->rate, + 1, GENMASK(timer->width - 1, 0)); + } + + return 0; +} + +static int rzn1_timer_probe_other(struct platform_device *pdev, struct rzn= 1_timer *tab_timers, + void __iomem *base, unsigned long clock_rate) +{ + struct device *dev =3D &pdev->dev; + struct rzn1_timer *timer; + unsigned int i; + char *name; + int irq; + int ret; + + /* + * Probe other instance(s), i.e. not the first one. In that case, + * all timers are used as clock events and available for all possible + * CPUs + * + * First step, perform all operation that could fail without calling + * clockevents_config_and_register(). Unregister counterpart does not + * exist and so, once called, we cannot remove the related resource. + */ + for (i =3D 0; i < RZN1_TIMER_NB_TIMERS; i++) { + timer =3D &tab_timers[i]; + + rzn1_timer_init(timer, i, base, clock_rate); + + irq =3D platform_get_irq(pdev, i); + if (irq < 0) + return irq; + + name =3D devm_kasprintf(dev, GFP_KERNEL, "%s-%u", dev_name(dev), i); + if (!name) + return -ENOMEM; + + rzn1_timer_clkevt_init_ced(timer, name, irq); + + ret =3D devm_request_irq(dev, timer->ced.irq, rzn1_timer_interrupt, + IRQF_TIMER, timer->ced.name, timer); + if (ret < 0) + return dev_err_probe(dev, irq, "timer%d: Failed to request IRQ\n", i); + + rzn1_timer_int_enable(timer); + } + + /* + * Second step, all operation that can fail have been called. We can + * register our timers + */ + + for (i =3D 0; i < RZN1_TIMER_NB_TIMERS; i++) { + timer =3D &tab_timers[i]; + clockevents_config_and_register(&timer->ced, timer->rate, + 1, GENMASK(timer->width - 1, 0)); + } + + return 0; +} + +static int rzn1_timer_probe(struct platform_device *pdev) +{ + struct device *dev =3D &pdev->dev; + struct rzn1_timer *tab_timers; + unsigned long clock_rate; + void __iomem *base; + struct clk *clk; + int ret; + + tab_timers =3D devm_kcalloc(dev, RZN1_TIMER_NB_TIMERS, sizeof(*tab_timers= ), + GFP_KERNEL); + if (!tab_timers) + return -ENOMEM; + + base =3D devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(base)) + return PTR_ERR(base); + + clk =3D devm_clk_get_enabled(dev, "pclk"); + if (IS_ERR(clk)) + return dev_err_probe(dev, PTR_ERR(clk), "Failed to get pclk\n"); + + clock_rate =3D clk_get_rate(clk); + + scoped_guard(mutex, &rzn1_global_timers_lock) { + ret =3D !rzn1_timer_instance ? + rzn1_timer_probe_first(pdev, tab_timers, base, clock_rate) : + rzn1_timer_probe_other(pdev, tab_timers, base, clock_rate); + if (!ret) + rzn1_timer_instance++; + } + + return ret; +} + +static const struct of_device_id rzn1_timer_of_match[] =3D { + { .compatible =3D "renesas,rzn1-timer", }, + { /* sentinel */ } +}; + +static struct platform_driver rzn1_timer_driver =3D { + .driver =3D { + .name =3D "rzn1_timer", + .of_match_table =3D rzn1_timer_of_match, + }, +}; +builtin_platform_driver_probe(rzn1_timer_driver, rzn1_timer_probe); --=20 2.53.0