From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A27EFC433F5 for ; Mon, 6 Sep 2021 18:36:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 908A86069E for ; Mon, 6 Sep 2021 18:36:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244575AbhIFShj (ORCPT ); Mon, 6 Sep 2021 14:37:39 -0400 Received: from mga14.intel.com ([192.55.52.115]:47238 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244435AbhIFShi (ORCPT ); Mon, 6 Sep 2021 14:37:38 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10099"; a="219714204" X-IronPort-AV: E=Sophos;i="5.85,273,1624345200"; d="scan'208";a="219714204" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Sep 2021 11:36:33 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.85,273,1624345200"; d="scan'208";a="579716470" Received: from bspteam04.iind.intel.com ([10.106.46.142]) by orsmga004.jf.intel.com with ESMTP; 06 Sep 2021 11:36:29 -0700 From: shruthi.sanil@intel.com To: daniel.lezcano@linaro.org, tglx@linutronix.de, robh+dt@kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Cc: andriy.shevchenko@linux.intel.com, kris.pan@linux.intel.com, mgross@linux.intel.com, srikanth.thokala@intel.com, lakshmi.bai.raja.subramanian@intel.com, mallikarjunappa.sangannavar@intel.com, shruthi.sanil@intel.com Subject: [PATCH v6 2/2] clocksource: Add Intel Keem Bay timer support Date: Tue, 7 Sep 2021 00:06:21 +0530 Message-Id: <20210906183621.21075-3-shruthi.sanil@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210906183621.21075-1-shruthi.sanil@intel.com> References: <20210906183621.21075-1-shruthi.sanil@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Shruthi Sanil The Intel Keem Bay timer driver supports clocksource and clockevent features for the timer IP used in Intel Keem Bay SoC. The timer block supports 1 free running counter and 8 timers. The free running counter can be used as a clocksource and the timers can be used as clockevent. Each timer is capable of generating individual interrupt. Both the features are enabled through the timer general config register. Reviewed-by: Andy Shevchenko Signed-off-by: Shruthi Sanil --- MAINTAINERS | 5 + drivers/clocksource/Kconfig | 11 ++ drivers/clocksource/Makefile | 1 + drivers/clocksource/timer-keembay.c | 252 ++++++++++++++++++++++++++++ 4 files changed, 269 insertions(+) create mode 100644 drivers/clocksource/timer-keembay.c diff --git a/MAINTAINERS b/MAINTAINERS index 4278b389218e..f6559dd92971 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9506,6 +9506,11 @@ F: drivers/crypto/keembay/keembay-ocs-hcu-core.c F: drivers/crypto/keembay/ocs-hcu.c F: drivers/crypto/keembay/ocs-hcu.h +INTEL KEEM BAY TIMER SUPPORT +M: Shruthi Sanil +S: Maintained +F: drivers/clocksource/timer-keembay.c + INTEL MANAGEMENT ENGINE (mei) M: Tomas Winkler L: linux-kernel@vger.kernel.org diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 0f5e3983951a..0dcf2c5aaaf2 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -708,4 +708,15 @@ config MICROCHIP_PIT64B modes and high resolution. It is used as a clocksource and a clockevent. +config KEEMBAY_TIMER + bool "Intel Keem Bay timer" + depends on ARCH_KEEMBAY || COMPILE_TEST + select TIMER_OF + help + This option enables the support for the Intel Keem Bay + general purpose timer and free running counter driver. + Each timer can generate an individual interrupt and + supports oneshot and periodic modes. + The 64-bit counter can be used as a clock source. + endmenu diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index c17ee32a7151..ea319063ba47 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -88,3 +88,4 @@ obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o obj-$(CONFIG_HYPERV_TIMER) += hyperv_timer.o obj-$(CONFIG_MICROCHIP_PIT64B) += timer-microchip-pit64b.o +obj-$(CONFIG_KEEMBAY_TIMER) += timer-keembay.o diff --git a/drivers/clocksource/timer-keembay.c b/drivers/clocksource/timer-keembay.c new file mode 100644 index 000000000000..8647a05edf2e --- /dev/null +++ b/drivers/clocksource/timer-keembay.c @@ -0,0 +1,252 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Intel Keem Bay Timer driver + * + * Copyright (C) 2020 Intel Corporation + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "timer-of.h" + +/* Timer register offset */ +#define TIM_CNT_VAL_OFFSET 0x0 +#define TIM_RELOAD_VAL_OFFSET 0x4 +#define TIM_CONFIG_OFFSET 0x8 + +/* Bit fields of timer general config register */ +#define TIM_CONFIG_PRESCALER_ENABLE BIT(2) +#define TIM_CONFIG_COUNTER_ENABLE BIT(0) + +/* Bit fields of timer config register */ +#define TIM_CONFIG_INTERRUPT_PENDING BIT(4) +#define TIM_CONFIG_INTERRUPT_ENABLE BIT(2) +#define TIM_CONFIG_RESTART BIT(1) +#define TIM_CONFIG_ENABLE BIT(0) + +#define TIM_GEN_MASK GENMASK(31, 12) +#define TIM_RATING 200 +#define TIM_CLKSRC_MASK_BITS 64 + +#define TIMER_NAME_SIZE 25 + +/* Provides a unique ID for each timer */ +static DEFINE_IDA(keembay_timer_ida); + +static inline void keembay_timer_enable(void __iomem *base, u32 flags) +{ + writel(TIM_CONFIG_ENABLE | flags, base + TIM_CONFIG_OFFSET); +} + +static inline void keembay_timer_disable(void __iomem *base) +{ + writel(0x0, base + TIM_CONFIG_OFFSET); +} + +static inline void keembay_timer_update_counter(void __iomem *base, u32 val) +{ + writel(val, base + TIM_CNT_VAL_OFFSET); + writel(val, base + TIM_RELOAD_VAL_OFFSET); +} + +static inline void keembay_timer_clear_pending_int(void __iomem *base) +{ + u32 val; + + val = readl(base + TIM_CONFIG_OFFSET); + val &= ~TIM_CONFIG_INTERRUPT_PENDING; + writel(val, base + TIM_CONFIG_OFFSET); +} + +static int keembay_timer_set_next_event(unsigned long evt, struct clock_event_device *ce) +{ + u32 flags = TIM_CONFIG_INTERRUPT_ENABLE; + struct timer_of *to = to_timer_of(ce); + void __iomem *tim_base = timer_of_base(to); + + keembay_timer_disable(tim_base); + keembay_timer_update_counter(tim_base, evt); + keembay_timer_enable(tim_base, flags); + + return 0; +} + +static int keembay_timer_periodic(struct clock_event_device *ce) +{ + u32 flags = TIM_CONFIG_INTERRUPT_ENABLE | TIM_CONFIG_RESTART; + struct timer_of *to = to_timer_of(ce); + void __iomem *tim_base = timer_of_base(to); + + keembay_timer_disable(tim_base); + keembay_timer_update_counter(tim_base, timer_of_period(to)); + keembay_timer_enable(tim_base, flags); + + return 0; +} + +static int keembay_timer_shutdown(struct clock_event_device *ce) +{ + struct timer_of *to = to_timer_of(ce); + + keembay_timer_disable(timer_of_base(to)); + + return 0; +} + +static irqreturn_t keembay_timer_isr(int irq, void *dev_id) +{ + struct clock_event_device *evt = dev_id; + struct timer_of *to = to_timer_of(evt); + void __iomem *tim_base = timer_of_base(to); + u32 val; + + val = readl(tim_base + TIM_CONFIG_OFFSET); + + if (val & TIM_CONFIG_RESTART) { + /* Clear interrupt for periodic timer*/ + keembay_timer_clear_pending_int(tim_base); + } else { + /* Disable the timer for one shot timer */ + keembay_timer_disable(tim_base); + } + + evt->event_handler(evt); + + return IRQ_HANDLED; +} + +static int __init keembay_clockevent_init(struct device_node *np) +{ + struct timer_of *keembay_ce_to; + struct regmap *regmap; + char *timer_name; + int timer_id; + int ret; + u32 val; + + regmap = device_node_to_regmap(np->parent); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + + ret = regmap_read(regmap, TIM_CONFIG_OFFSET, &val); + if (ret) + return ret; + + /* Prescaler bit must be enabled for the timer to function */ + if (!(val & TIM_CONFIG_PRESCALER_ENABLE)) { + pr_err("%pOF: Prescaler is not enabled\n", np); + ret = -ENODEV; + } + + keembay_ce_to = kzalloc(sizeof(*keembay_ce_to), GFP_KERNEL); + if (!keembay_ce_to) + ret = -ENOMEM; + + timer_id = ida_alloc(&keembay_timer_ida, GFP_KERNEL); + if (timer_id < 0) { + ret = timer_id; + goto err_keembay_ce_to_free; + } + + timer_name = kasprintf(GFP_KERNEL, "keembay_timer%d", timer_id); + if (!timer_name) { + ret = -ENOMEM; + goto err_free_ida; + } + + keembay_ce_to->flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK; + keembay_ce_to->clkevt.name = timer_name; + keembay_ce_to->clkevt.cpumask = cpumask_of(0); + keembay_ce_to->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT | + CLOCK_EVT_FEAT_DYNIRQ; + keembay_ce_to->clkevt.rating = TIM_RATING; + keembay_ce_to->clkevt.set_next_event = keembay_timer_set_next_event; + keembay_ce_to->clkevt.set_state_periodic = keembay_timer_periodic; + keembay_ce_to->clkevt.set_state_shutdown = keembay_timer_shutdown; + keembay_ce_to->of_irq.handler = keembay_timer_isr; + keembay_ce_to->of_irq.flags = IRQF_TIMER; + + ret = timer_of_init(np, keembay_ce_to); + if (ret) + goto err_timer_name_free; + + ret = regmap_read(regmap, TIM_RELOAD_VAL_OFFSET, &val); + if (ret) + goto err_timer_name_free; + + keembay_ce_to->of_clk.rate = keembay_ce_to->of_clk.rate / (val + 1); + + clockevents_config_and_register(&keembay_ce_to->clkevt, + timer_of_rate(keembay_ce_to), + 1, + U32_MAX); + + return 0; + +err_timer_name_free: + kfree(timer_name); +err_free_ida: + ida_free(&keembay_timer_ida, timer_id); +err_keembay_ce_to_free: + kfree(keembay_ce_to); + + return ret; +} + +static struct timer_of keembay_cs_to = { + .flags = TIMER_OF_BASE | TIMER_OF_CLOCK, +}; + +static u64 notrace keembay_clocksource_read(struct clocksource *cs) +{ + return lo_hi_readq(timer_of_base(&keembay_cs_to)); +} + +static struct clocksource keembay_counter = { + .name = "keembay_sys_counter", + .rating = TIM_RATING, + .read = keembay_clocksource_read, + .mask = CLOCKSOURCE_MASK(TIM_CLKSRC_MASK_BITS), + .flags = CLOCK_SOURCE_IS_CONTINUOUS | + CLOCK_SOURCE_SUSPEND_NONSTOP, +}; + +static int __init keembay_clocksource_init(struct device_node *np) +{ + struct regmap *regmap; + u32 val; + int ret; + + regmap = device_node_to_regmap(np->parent); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + + ret = regmap_read(regmap, TIM_CONFIG_OFFSET, &val); + if (ret) + return ret; + + /* Free Running Counter bit must be enabled for counter to function */ + if (!(val & TIM_CONFIG_COUNTER_ENABLE)) { + pr_err("%pOF: free running counter is not enabled\n", np); + return -ENODEV; + } + + ret = timer_of_init(np, &keembay_cs_to); + if (ret) + return ret; + + return clocksource_register_hz(&keembay_counter, timer_of_rate(&keembay_cs_to)); +} + +TIMER_OF_DECLARE(keembay_clockevent, "intel,keembay-timer", keembay_clockevent_init); +TIMER_OF_DECLARE(keembay_clocksource, "intel,keembay-counter", keembay_clocksource_init); -- 2.17.1