From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757888AbbLBJio (ORCPT ); Wed, 2 Dec 2015 04:38:44 -0500 Received: from eu-smtp-delivery-143.mimecast.com ([146.101.78.143]:31246 "EHLO eu-smtp-delivery-143.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756582AbbLBJdh (ORCPT ); Wed, 2 Dec 2015 04:33:37 -0500 From: Vladimir Murzin To: arnd@arndb.de, linux@arm.linux.org.uk, gregkh@linuxfoundation.org, daniel.lezcano@linaro.org, tglx@linutronix.de, u.kleine-koenig@pengutronix.de, afaerber@suse.de, mcoquelin.stm32@gmail.com Cc: Mark.Rutland@arm.com, Pawel.Moll@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, jslaby@suse.cz, robh+dt@kernel.org, devicetree@vger.kernel.org, linux-serial@vger.kernel.org, linux-api@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v1 02/10] clockevents/drivers: add MPS2 Timer driver Date: Wed, 2 Dec 2015 09:33:02 +0000 Message-Id: <1449048790-25859-3-git-send-email-vladimir.murzin@arm.com> X-Mailer: git-send-email 2.0.0 In-Reply-To: <1449048790-25859-1-git-send-email-vladimir.murzin@arm.com> References: <1449048790-25859-1-git-send-email-vladimir.murzin@arm.com> X-OriginalArrivalTime: 02 Dec 2015 09:33:28.0933 (UTC) FILETIME=[806E4150:01D12CE4] X-MC-Unique: X25DlLpeQ-qy0us3Z8g4kQ-5 Content-Type: text/plain; charset=WINDOWS-1252 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id tB29coiU002423 MPS2 platform has simple 32 bits general purpose countdown timers. The driver uses the first detected timer as a clocksource and the rest of the timers as a clockevent Signed-off-by: Vladimir Murzin --- drivers/clocksource/Kconfig | 5 + drivers/clocksource/Makefile | 1 + drivers/clocksource/mps2-timer.c | 277 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 283 insertions(+) create mode 100644 drivers/clocksource/mps2-timer.c diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 2eb5f0e..8bca09c 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -137,6 +137,11 @@ config CLKSRC_STM32 depends on OF && ARM && (ARCH_STM32 || COMPILE_TEST) select CLKSRC_MMIO +config CLKSRC_MPS2 + bool "Clocksource for MPS2 SoCs" if COMPILE_TEST + depends on OF && ARM + select CLKSRC_MMIO + config ARM_ARCH_TIMER bool select CLKSRC_OF if OF diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 56bd16e..7033b9c 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -39,6 +39,7 @@ obj-$(CONFIG_CLKSRC_EFM32) += time-efm32.o obj-$(CONFIG_CLKSRC_STM32) += timer-stm32.o obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exynos_mct.o obj-$(CONFIG_CLKSRC_LPC32XX) += time-lpc32xx.o +obj-$(CONFIG_CLKSRC_MPS2) += mps2-timer.o obj-$(CONFIG_CLKSRC_SAMSUNG_PWM) += samsung_pwm_timer.o obj-$(CONFIG_FSL_FTM_TIMER) += fsl_ftm_timer.o obj-$(CONFIG_VF_PIT_TIMER) += vf_pit_timer.o diff --git a/drivers/clocksource/mps2-timer.c b/drivers/clocksource/mps2-timer.c new file mode 100644 index 0000000..3e19af5 --- /dev/null +++ b/drivers/clocksource/mps2-timer.c @@ -0,0 +1,277 @@ +/* + * Copyright (C) 2015 ARM Limited + * + * Author: Vladimir Murzin + * + * 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. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define TIMER_CTRL 0x0 +#define TIMER_CTRL_ENABLE BIT(0) +#define TIMER_CTRL_IE BIT(3) + +#define TIMER_VALUE 0x4 +#define TIMER_RELOAD 0x8 +#define TIMER_INT 0xc + +struct clockevent_mps2 { + void __iomem *reg; + u32 clock_count_per_tick; + struct clock_event_device clkevt; +}; + +static void __iomem *sched_clock_base; + +static u64 notrace mps2_sched_read(void) +{ + return ~readl_relaxed(sched_clock_base + TIMER_VALUE); +} + +static inline struct clockevent_mps2 *to_mps2_clkevt(struct clock_event_device *c) +{ + return container_of(c, struct clockevent_mps2, clkevt); +} + +static void clockevent_mps2_writel(u32 val, struct clock_event_device *c, u32 offset) +{ + writel(val, to_mps2_clkevt(c)->reg + offset); +} + +static int mps2_timer_shutdown(struct clock_event_device *ce) +{ + clockevent_mps2_writel(0, ce, TIMER_RELOAD); + clockevent_mps2_writel(0, ce, TIMER_CTRL); + + return 0; +} + +static int mps2_timer_set_next_event(unsigned long next, struct clock_event_device *ce) +{ + clockevent_mps2_writel(next, ce, TIMER_VALUE); + clockevent_mps2_writel(TIMER_CTRL_IE | TIMER_CTRL_ENABLE, ce, TIMER_CTRL); + + return 0; +} + +static int mps2_timer_set_periodic(struct clock_event_device *ce) +{ + u32 clock_count_per_tick = to_mps2_clkevt(ce)->clock_count_per_tick; + + clockevent_mps2_writel(clock_count_per_tick, ce, TIMER_RELOAD); + clockevent_mps2_writel(clock_count_per_tick, ce, TIMER_VALUE); + clockevent_mps2_writel(TIMER_CTRL_IE | TIMER_CTRL_ENABLE, ce, TIMER_CTRL); + + return 0; +} + +static irqreturn_t mps2_timer_interrupt(int irq, void *dev_id) +{ + struct clockevent_mps2 *ce = dev_id; + u32 status = readl(ce->reg + TIMER_INT); + + if (!status) { + pr_warn("spuirous interrupt\n"); + return IRQ_NONE; + } + + writel(1, ce->reg + TIMER_INT); + + ce->clkevt.event_handler(&ce->clkevt); + + return IRQ_HANDLED; +} + +static int __init mps2_clockevent_init(struct device_node *np) +{ + void __iomem *base; + struct clk *clk; + struct clockevent_mps2 *ce; + u32 rate; + int irq, ret; + const char *name = "mps2-clkevt"; + + ret = of_property_read_u32(np, "clock-frequency", &rate); + if (ret) { + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + pr_err("failed to get clock for clockevent: %d\n", ret); + goto err_clk_get; + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("failed to enable clock for clockevent: %d\n", ret); + clk_put(clk); + goto err_clk_enable; + } + + rate = clk_get_rate(clk); + } + + base = of_iomap(np, 0); + if (!base) { + ret = -EADDRNOTAVAIL; + pr_err("failed to map register for clockevent: %d\n", ret); + goto err_iomap; + } + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + ret = -ENOENT; + pr_err("failed to get irq for clockevent: %d\n", ret); + goto err_get_irq; + } + + ce = kzalloc(sizeof(struct clockevent_mps2), GFP_KERNEL); + if (!ce) { + ret = -ENOMEM; + pr_err("failed to allocate clockevent: %d\n", ret); + goto err_ce_alloc; + } + + ce->reg = base; + ce->clock_count_per_tick = DIV_ROUND_CLOSEST(rate, HZ); + ce->clkevt.irq = irq; + ce->clkevt.name = name; + ce->clkevt.rating = 200; + ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + ce->clkevt.cpumask = cpu_possible_mask; + ce->clkevt.set_state_shutdown = mps2_timer_shutdown, + ce->clkevt.set_state_periodic = mps2_timer_set_periodic, + ce->clkevt.set_state_oneshot = mps2_timer_shutdown, + ce->clkevt.set_next_event = mps2_timer_set_next_event; + + /* Ensure timer is disabled */ + writel(0, base + TIMER_CTRL); + + ret = request_irq(irq, mps2_timer_interrupt, IRQF_TIMER, name, ce); + if (ret) { + pr_err("failed to request irq: %d\n", ret); + goto err_ia_alloc; + } + + clockevents_config_and_register(&ce->clkevt, rate, 0xf, 0xffffffff); + + return 0; + +err_ia_alloc: + kfree(ce); +err_ce_alloc: +err_get_irq: + iounmap(base); +err_iomap: + clk_disable_unprepare(clk); +err_clk_enable: + clk_put(clk); +err_clk_get: + return ret; +} + +static int __init mps2_clocksource_init(struct device_node *np) +{ + void __iomem *base; + struct clk *clk; + u32 rate; + int ret; + const char *name = "mps2-clksrc"; + + ret = of_property_read_u32(np, "clock-frequency", &rate); + if (ret) { + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + pr_err("failed to get clock for clocksource: %d\n", ret); + goto err_clk_get; + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("failed to enable clock for clocksource: %d\n", ret); + clk_put(clk); + goto err_clk_enable; + } + + rate = clk_get_rate(clk); + } + + base = of_iomap(np, 0); + if (!base) { + ret = -EADDRNOTAVAIL; + pr_err("failed to map register for clocksource: %d\n", ret); + goto err_iomap; + } + + /* Ensure timer is disabled */ + writel(0, base + TIMER_CTRL); + + /* ... and set it up as free-running clocksource */ + writel(0xffffffff, base + TIMER_VALUE); + writel(0xffffffff, base + TIMER_RELOAD); + + writel(TIMER_CTRL_ENABLE, base + TIMER_CTRL); + + ret = clocksource_mmio_init(base + TIMER_VALUE, name, + rate, 200, 32, + clocksource_mmio_readl_down); + if (ret) { + pr_err("failed to init clocksource: %d\n", ret); + goto err_clocksource_init; + } + + sched_clock_base = base; + sched_clock_register(mps2_sched_read, 32, rate); + + return 0; + +err_clocksource_init: + iounmap(base); +err_iomap: + clk_disable_unprepare(clk); +err_clk_enable: + clk_put(clk); +err_clk_get: + return ret; +} + +static void __init mps2_timer_init(struct device_node *np) +{ + static int has_clocksource, has_clockevent; + int ret; + + if (!has_clocksource) { + ret = mps2_clocksource_init(np); + if (!ret) { + has_clocksource = 1; + return; + } + } + + if (!has_clockevent) { + ret = mps2_clockevent_init(np); + if (!ret) { + has_clockevent = 1; + return; + } + } +} + +CLOCKSOURCE_OF_DECLARE(mps2_timer, "arm,mps2-timer", mps2_timer_init); -- 1.7.9.5 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladimir Murzin Subject: [PATCH v1 02/10] clockevents/drivers: add MPS2 Timer driver Date: Wed, 2 Dec 2015 09:33:02 +0000 Message-ID: <1449048790-25859-3-git-send-email-vladimir.murzin@arm.com> References: <1449048790-25859-1-git-send-email-vladimir.murzin@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1449048790-25859-1-git-send-email-vladimir.murzin@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: arnd@arndb.de, linux@arm.linux.org.uk, gregkh@linuxfoundation.org, daniel.lezcano@linaro.org, tglx@linutronix.de, u.kleine-koenig@pengutronix.de, afaerber@suse.de, mcoquelin.stm32@gmail.com Cc: Mark.Rutland@arm.com, devicetree@vger.kernel.org, Pawel.Moll@arm.com, ijc+devicetree@hellion.org.uk, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, linux-serial@vger.kernel.org, galak@codeaurora.org, jslaby@suse.cz, linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org MPS2 platform has simple 32 bits general purpose countdown timers. The driver uses the first detected timer as a clocksource and the rest of the timers as a clockevent Signed-off-by: Vladimir Murzin --- drivers/clocksource/Kconfig | 5 + drivers/clocksource/Makefile | 1 + drivers/clocksource/mps2-timer.c | 277 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 283 insertions(+) create mode 100644 drivers/clocksource/mps2-timer.c diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 2eb5f0e..8bca09c 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -137,6 +137,11 @@ config CLKSRC_STM32 depends on OF && ARM && (ARCH_STM32 || COMPILE_TEST) select CLKSRC_MMIO +config CLKSRC_MPS2 + bool "Clocksource for MPS2 SoCs" if COMPILE_TEST + depends on OF && ARM + select CLKSRC_MMIO + config ARM_ARCH_TIMER bool select CLKSRC_OF if OF diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 56bd16e..7033b9c 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -39,6 +39,7 @@ obj-$(CONFIG_CLKSRC_EFM32) += time-efm32.o obj-$(CONFIG_CLKSRC_STM32) += timer-stm32.o obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exynos_mct.o obj-$(CONFIG_CLKSRC_LPC32XX) += time-lpc32xx.o +obj-$(CONFIG_CLKSRC_MPS2) += mps2-timer.o obj-$(CONFIG_CLKSRC_SAMSUNG_PWM) += samsung_pwm_timer.o obj-$(CONFIG_FSL_FTM_TIMER) += fsl_ftm_timer.o obj-$(CONFIG_VF_PIT_TIMER) += vf_pit_timer.o diff --git a/drivers/clocksource/mps2-timer.c b/drivers/clocksource/mps2-timer.c new file mode 100644 index 0000000..3e19af5 --- /dev/null +++ b/drivers/clocksource/mps2-timer.c @@ -0,0 +1,277 @@ +/* + * Copyright (C) 2015 ARM Limited + * + * Author: Vladimir Murzin + * + * 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. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define TIMER_CTRL 0x0 +#define TIMER_CTRL_ENABLE BIT(0) +#define TIMER_CTRL_IE BIT(3) + +#define TIMER_VALUE 0x4 +#define TIMER_RELOAD 0x8 +#define TIMER_INT 0xc + +struct clockevent_mps2 { + void __iomem *reg; + u32 clock_count_per_tick; + struct clock_event_device clkevt; +}; + +static void __iomem *sched_clock_base; + +static u64 notrace mps2_sched_read(void) +{ + return ~readl_relaxed(sched_clock_base + TIMER_VALUE); +} + +static inline struct clockevent_mps2 *to_mps2_clkevt(struct clock_event_device *c) +{ + return container_of(c, struct clockevent_mps2, clkevt); +} + +static void clockevent_mps2_writel(u32 val, struct clock_event_device *c, u32 offset) +{ + writel(val, to_mps2_clkevt(c)->reg + offset); +} + +static int mps2_timer_shutdown(struct clock_event_device *ce) +{ + clockevent_mps2_writel(0, ce, TIMER_RELOAD); + clockevent_mps2_writel(0, ce, TIMER_CTRL); + + return 0; +} + +static int mps2_timer_set_next_event(unsigned long next, struct clock_event_device *ce) +{ + clockevent_mps2_writel(next, ce, TIMER_VALUE); + clockevent_mps2_writel(TIMER_CTRL_IE | TIMER_CTRL_ENABLE, ce, TIMER_CTRL); + + return 0; +} + +static int mps2_timer_set_periodic(struct clock_event_device *ce) +{ + u32 clock_count_per_tick = to_mps2_clkevt(ce)->clock_count_per_tick; + + clockevent_mps2_writel(clock_count_per_tick, ce, TIMER_RELOAD); + clockevent_mps2_writel(clock_count_per_tick, ce, TIMER_VALUE); + clockevent_mps2_writel(TIMER_CTRL_IE | TIMER_CTRL_ENABLE, ce, TIMER_CTRL); + + return 0; +} + +static irqreturn_t mps2_timer_interrupt(int irq, void *dev_id) +{ + struct clockevent_mps2 *ce = dev_id; + u32 status = readl(ce->reg + TIMER_INT); + + if (!status) { + pr_warn("spuirous interrupt\n"); + return IRQ_NONE; + } + + writel(1, ce->reg + TIMER_INT); + + ce->clkevt.event_handler(&ce->clkevt); + + return IRQ_HANDLED; +} + +static int __init mps2_clockevent_init(struct device_node *np) +{ + void __iomem *base; + struct clk *clk; + struct clockevent_mps2 *ce; + u32 rate; + int irq, ret; + const char *name = "mps2-clkevt"; + + ret = of_property_read_u32(np, "clock-frequency", &rate); + if (ret) { + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + pr_err("failed to get clock for clockevent: %d\n", ret); + goto err_clk_get; + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("failed to enable clock for clockevent: %d\n", ret); + clk_put(clk); + goto err_clk_enable; + } + + rate = clk_get_rate(clk); + } + + base = of_iomap(np, 0); + if (!base) { + ret = -EADDRNOTAVAIL; + pr_err("failed to map register for clockevent: %d\n", ret); + goto err_iomap; + } + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + ret = -ENOENT; + pr_err("failed to get irq for clockevent: %d\n", ret); + goto err_get_irq; + } + + ce = kzalloc(sizeof(struct clockevent_mps2), GFP_KERNEL); + if (!ce) { + ret = -ENOMEM; + pr_err("failed to allocate clockevent: %d\n", ret); + goto err_ce_alloc; + } + + ce->reg = base; + ce->clock_count_per_tick = DIV_ROUND_CLOSEST(rate, HZ); + ce->clkevt.irq = irq; + ce->clkevt.name = name; + ce->clkevt.rating = 200; + ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + ce->clkevt.cpumask = cpu_possible_mask; + ce->clkevt.set_state_shutdown = mps2_timer_shutdown, + ce->clkevt.set_state_periodic = mps2_timer_set_periodic, + ce->clkevt.set_state_oneshot = mps2_timer_shutdown, + ce->clkevt.set_next_event = mps2_timer_set_next_event; + + /* Ensure timer is disabled */ + writel(0, base + TIMER_CTRL); + + ret = request_irq(irq, mps2_timer_interrupt, IRQF_TIMER, name, ce); + if (ret) { + pr_err("failed to request irq: %d\n", ret); + goto err_ia_alloc; + } + + clockevents_config_and_register(&ce->clkevt, rate, 0xf, 0xffffffff); + + return 0; + +err_ia_alloc: + kfree(ce); +err_ce_alloc: +err_get_irq: + iounmap(base); +err_iomap: + clk_disable_unprepare(clk); +err_clk_enable: + clk_put(clk); +err_clk_get: + return ret; +} + +static int __init mps2_clocksource_init(struct device_node *np) +{ + void __iomem *base; + struct clk *clk; + u32 rate; + int ret; + const char *name = "mps2-clksrc"; + + ret = of_property_read_u32(np, "clock-frequency", &rate); + if (ret) { + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + pr_err("failed to get clock for clocksource: %d\n", ret); + goto err_clk_get; + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("failed to enable clock for clocksource: %d\n", ret); + clk_put(clk); + goto err_clk_enable; + } + + rate = clk_get_rate(clk); + } + + base = of_iomap(np, 0); + if (!base) { + ret = -EADDRNOTAVAIL; + pr_err("failed to map register for clocksource: %d\n", ret); + goto err_iomap; + } + + /* Ensure timer is disabled */ + writel(0, base + TIMER_CTRL); + + /* ... and set it up as free-running clocksource */ + writel(0xffffffff, base + TIMER_VALUE); + writel(0xffffffff, base + TIMER_RELOAD); + + writel(TIMER_CTRL_ENABLE, base + TIMER_CTRL); + + ret = clocksource_mmio_init(base + TIMER_VALUE, name, + rate, 200, 32, + clocksource_mmio_readl_down); + if (ret) { + pr_err("failed to init clocksource: %d\n", ret); + goto err_clocksource_init; + } + + sched_clock_base = base; + sched_clock_register(mps2_sched_read, 32, rate); + + return 0; + +err_clocksource_init: + iounmap(base); +err_iomap: + clk_disable_unprepare(clk); +err_clk_enable: + clk_put(clk); +err_clk_get: + return ret; +} + +static void __init mps2_timer_init(struct device_node *np) +{ + static int has_clocksource, has_clockevent; + int ret; + + if (!has_clocksource) { + ret = mps2_clocksource_init(np); + if (!ret) { + has_clocksource = 1; + return; + } + } + + if (!has_clockevent) { + ret = mps2_clockevent_init(np); + if (!ret) { + has_clockevent = 1; + return; + } + } +} + +CLOCKSOURCE_OF_DECLARE(mps2_timer, "arm,mps2-timer", mps2_timer_init); -- 1.7.9.5 From mboxrd@z Thu Jan 1 00:00:00 1970 From: vladimir.murzin@arm.com (Vladimir Murzin) Date: Wed, 2 Dec 2015 09:33:02 +0000 Subject: [PATCH v1 02/10] clockevents/drivers: add MPS2 Timer driver In-Reply-To: <1449048790-25859-1-git-send-email-vladimir.murzin@arm.com> References: <1449048790-25859-1-git-send-email-vladimir.murzin@arm.com> Message-ID: <1449048790-25859-3-git-send-email-vladimir.murzin@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org MPS2 platform has simple 32 bits general purpose countdown timers. The driver uses the first detected timer as a clocksource and the rest of the timers as a clockevent Signed-off-by: Vladimir Murzin --- drivers/clocksource/Kconfig | 5 + drivers/clocksource/Makefile | 1 + drivers/clocksource/mps2-timer.c | 277 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 283 insertions(+) create mode 100644 drivers/clocksource/mps2-timer.c diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 2eb5f0e..8bca09c 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -137,6 +137,11 @@ config CLKSRC_STM32 depends on OF && ARM && (ARCH_STM32 || COMPILE_TEST) select CLKSRC_MMIO +config CLKSRC_MPS2 + bool "Clocksource for MPS2 SoCs" if COMPILE_TEST + depends on OF && ARM + select CLKSRC_MMIO + config ARM_ARCH_TIMER bool select CLKSRC_OF if OF diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 56bd16e..7033b9c 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -39,6 +39,7 @@ obj-$(CONFIG_CLKSRC_EFM32) += time-efm32.o obj-$(CONFIG_CLKSRC_STM32) += timer-stm32.o obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exynos_mct.o obj-$(CONFIG_CLKSRC_LPC32XX) += time-lpc32xx.o +obj-$(CONFIG_CLKSRC_MPS2) += mps2-timer.o obj-$(CONFIG_CLKSRC_SAMSUNG_PWM) += samsung_pwm_timer.o obj-$(CONFIG_FSL_FTM_TIMER) += fsl_ftm_timer.o obj-$(CONFIG_VF_PIT_TIMER) += vf_pit_timer.o diff --git a/drivers/clocksource/mps2-timer.c b/drivers/clocksource/mps2-timer.c new file mode 100644 index 0000000..3e19af5 --- /dev/null +++ b/drivers/clocksource/mps2-timer.c @@ -0,0 +1,277 @@ +/* + * Copyright (C) 2015 ARM Limited + * + * Author: Vladimir Murzin + * + * 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. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define TIMER_CTRL 0x0 +#define TIMER_CTRL_ENABLE BIT(0) +#define TIMER_CTRL_IE BIT(3) + +#define TIMER_VALUE 0x4 +#define TIMER_RELOAD 0x8 +#define TIMER_INT 0xc + +struct clockevent_mps2 { + void __iomem *reg; + u32 clock_count_per_tick; + struct clock_event_device clkevt; +}; + +static void __iomem *sched_clock_base; + +static u64 notrace mps2_sched_read(void) +{ + return ~readl_relaxed(sched_clock_base + TIMER_VALUE); +} + +static inline struct clockevent_mps2 *to_mps2_clkevt(struct clock_event_device *c) +{ + return container_of(c, struct clockevent_mps2, clkevt); +} + +static void clockevent_mps2_writel(u32 val, struct clock_event_device *c, u32 offset) +{ + writel(val, to_mps2_clkevt(c)->reg + offset); +} + +static int mps2_timer_shutdown(struct clock_event_device *ce) +{ + clockevent_mps2_writel(0, ce, TIMER_RELOAD); + clockevent_mps2_writel(0, ce, TIMER_CTRL); + + return 0; +} + +static int mps2_timer_set_next_event(unsigned long next, struct clock_event_device *ce) +{ + clockevent_mps2_writel(next, ce, TIMER_VALUE); + clockevent_mps2_writel(TIMER_CTRL_IE | TIMER_CTRL_ENABLE, ce, TIMER_CTRL); + + return 0; +} + +static int mps2_timer_set_periodic(struct clock_event_device *ce) +{ + u32 clock_count_per_tick = to_mps2_clkevt(ce)->clock_count_per_tick; + + clockevent_mps2_writel(clock_count_per_tick, ce, TIMER_RELOAD); + clockevent_mps2_writel(clock_count_per_tick, ce, TIMER_VALUE); + clockevent_mps2_writel(TIMER_CTRL_IE | TIMER_CTRL_ENABLE, ce, TIMER_CTRL); + + return 0; +} + +static irqreturn_t mps2_timer_interrupt(int irq, void *dev_id) +{ + struct clockevent_mps2 *ce = dev_id; + u32 status = readl(ce->reg + TIMER_INT); + + if (!status) { + pr_warn("spuirous interrupt\n"); + return IRQ_NONE; + } + + writel(1, ce->reg + TIMER_INT); + + ce->clkevt.event_handler(&ce->clkevt); + + return IRQ_HANDLED; +} + +static int __init mps2_clockevent_init(struct device_node *np) +{ + void __iomem *base; + struct clk *clk; + struct clockevent_mps2 *ce; + u32 rate; + int irq, ret; + const char *name = "mps2-clkevt"; + + ret = of_property_read_u32(np, "clock-frequency", &rate); + if (ret) { + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + pr_err("failed to get clock for clockevent: %d\n", ret); + goto err_clk_get; + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("failed to enable clock for clockevent: %d\n", ret); + clk_put(clk); + goto err_clk_enable; + } + + rate = clk_get_rate(clk); + } + + base = of_iomap(np, 0); + if (!base) { + ret = -EADDRNOTAVAIL; + pr_err("failed to map register for clockevent: %d\n", ret); + goto err_iomap; + } + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + ret = -ENOENT; + pr_err("failed to get irq for clockevent: %d\n", ret); + goto err_get_irq; + } + + ce = kzalloc(sizeof(struct clockevent_mps2), GFP_KERNEL); + if (!ce) { + ret = -ENOMEM; + pr_err("failed to allocate clockevent: %d\n", ret); + goto err_ce_alloc; + } + + ce->reg = base; + ce->clock_count_per_tick = DIV_ROUND_CLOSEST(rate, HZ); + ce->clkevt.irq = irq; + ce->clkevt.name = name; + ce->clkevt.rating = 200; + ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + ce->clkevt.cpumask = cpu_possible_mask; + ce->clkevt.set_state_shutdown = mps2_timer_shutdown, + ce->clkevt.set_state_periodic = mps2_timer_set_periodic, + ce->clkevt.set_state_oneshot = mps2_timer_shutdown, + ce->clkevt.set_next_event = mps2_timer_set_next_event; + + /* Ensure timer is disabled */ + writel(0, base + TIMER_CTRL); + + ret = request_irq(irq, mps2_timer_interrupt, IRQF_TIMER, name, ce); + if (ret) { + pr_err("failed to request irq: %d\n", ret); + goto err_ia_alloc; + } + + clockevents_config_and_register(&ce->clkevt, rate, 0xf, 0xffffffff); + + return 0; + +err_ia_alloc: + kfree(ce); +err_ce_alloc: +err_get_irq: + iounmap(base); +err_iomap: + clk_disable_unprepare(clk); +err_clk_enable: + clk_put(clk); +err_clk_get: + return ret; +} + +static int __init mps2_clocksource_init(struct device_node *np) +{ + void __iomem *base; + struct clk *clk; + u32 rate; + int ret; + const char *name = "mps2-clksrc"; + + ret = of_property_read_u32(np, "clock-frequency", &rate); + if (ret) { + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + pr_err("failed to get clock for clocksource: %d\n", ret); + goto err_clk_get; + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("failed to enable clock for clocksource: %d\n", ret); + clk_put(clk); + goto err_clk_enable; + } + + rate = clk_get_rate(clk); + } + + base = of_iomap(np, 0); + if (!base) { + ret = -EADDRNOTAVAIL; + pr_err("failed to map register for clocksource: %d\n", ret); + goto err_iomap; + } + + /* Ensure timer is disabled */ + writel(0, base + TIMER_CTRL); + + /* ... and set it up as free-running clocksource */ + writel(0xffffffff, base + TIMER_VALUE); + writel(0xffffffff, base + TIMER_RELOAD); + + writel(TIMER_CTRL_ENABLE, base + TIMER_CTRL); + + ret = clocksource_mmio_init(base + TIMER_VALUE, name, + rate, 200, 32, + clocksource_mmio_readl_down); + if (ret) { + pr_err("failed to init clocksource: %d\n", ret); + goto err_clocksource_init; + } + + sched_clock_base = base; + sched_clock_register(mps2_sched_read, 32, rate); + + return 0; + +err_clocksource_init: + iounmap(base); +err_iomap: + clk_disable_unprepare(clk); +err_clk_enable: + clk_put(clk); +err_clk_get: + return ret; +} + +static void __init mps2_timer_init(struct device_node *np) +{ + static int has_clocksource, has_clockevent; + int ret; + + if (!has_clocksource) { + ret = mps2_clocksource_init(np); + if (!ret) { + has_clocksource = 1; + return; + } + } + + if (!has_clockevent) { + ret = mps2_clockevent_init(np); + if (!ret) { + has_clockevent = 1; + return; + } + } +} + +CLOCKSOURCE_OF_DECLARE(mps2_timer, "arm,mps2-timer", mps2_timer_init); -- 1.7.9.5