From patchwork Wed Feb 8 23:14:40 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Lezcano X-Patchwork-Id: 9563757 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 6EAE66020F for ; Wed, 8 Feb 2017 23:18:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 24CFB2852B for ; Wed, 8 Feb 2017 23:18:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 19D0028532; Wed, 8 Feb 2017 23:18:15 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_SORBS_SPAM,T_DKIM_INVALID autolearn=no version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 6BA262852B for ; Wed, 8 Feb 2017 23:18:14 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1cbbUU-0002Rp-Ao; Wed, 08 Feb 2017 23:17:34 +0000 Received: from mail-wm0-f44.google.com ([74.125.82.44]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1cbbUJ-0002Ds-Hh for linux-arm-kernel@lists.infradead.org; Wed, 08 Feb 2017 23:17:30 +0000 Received: by mail-wm0-f44.google.com with SMTP id v77so3311767wmv.0 for ; Wed, 08 Feb 2017 15:17:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=+/OLq0bm37ktKVVxBmJBERbHcromzX0GHVJsMb5cck8=; b=fofeUhTONLSo11pkFxQTF3Mkjn+CXKXHXND9c4sIIS1P5mHHbyps5UgZMLTR9gQ47+ Z571R3QJkIVNGEKgDtX7HLmr5V0a0iSknKHin+xsqcCNoPUFIi5pILwegq7nGfzxrscj 9+nFMRJuJ8tPp4xLiKgK07RKuq7MaFVuC3YLk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=+/OLq0bm37ktKVVxBmJBERbHcromzX0GHVJsMb5cck8=; b=VlTeVcOy+1QL2nbab6hOkv4s//kaRzEfVMZzpSrCqKmL0jEEuEB6jBC6LIaTBBc8L+ Oo7T0CkUXVid/durULTJsy32RZAOWj39QMxF/Ip3IVbaXq5jHTeKejnYoFxcGlBq5goj jkqseUUtpQWip5WXIdZEFSWtKSOSF2efG9rTT73kaatbu0jxRg8h3UeNcL/wG7S156j7 lx8xGHmgXQiE4KOH6sDzz1jQee7pWtRHsBiR3pV/Lgw5jHQN3qYpZQu5DxNy/NyAf+Ip 4D8mg0t/WPoJ1ObaAMtCF+RuRfp5ki0sE9+A9/718mePmX0kM+Gjlz2oWqG8BrzNOkkx 0m/Q== X-Gm-Message-State: AMke39lzudmOF3JvbXC7UKPTlv/aml/GfQg9bO7ePlIHzJu96sI5igQuBFhnrrobpYRRH89A X-Received: by 10.28.141.199 with SMTP id p190mr372734wmd.89.1486595761597; Wed, 08 Feb 2017 15:16:01 -0800 (PST) Received: from mai.lan ([2001:41d0:fe90:b800:3f16:bcf7:601c:a13b]) by smtp.gmail.com with ESMTPSA id u42sm15422821wrc.1.2017.02.08.15.15.59 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 08 Feb 2017 15:16:00 -0800 (PST) From: Daniel Lezcano To: tglx@linutronix.de Subject: [PATCH 06/10] clocksource/drivers/ostm: Add renesas-ostm timer driver Date: Thu, 9 Feb 2017 00:14:40 +0100 Message-Id: <1486595685-10232-6-git-send-email-daniel.lezcano@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1486595685-10232-1-git-send-email-daniel.lezcano@linaro.org> References: <20170208231208.GB12695@mai> <1486595685-10232-1-git-send-email-daniel.lezcano@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170208_151724_069933_AE2E619E X-CRM114-Status: GOOD ( 24.68 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Magnus Damm , Russell King , open list , "open list:ARM/SHMOBILE ARM ARCHITECTURE" , Chris Brandt , Simon Horman , "moderated list:ARM SUB-ARCHITECTURES" MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Chris Brandt This patch adds a OSTM driver for the Renesas architecture. The OS Timer (OSTM) has independent channels that can be used as a freerun or interval times. This driver uses the first probed device as a clocksource and then any additional devices as clock events. Signed-off-by: Chris Brandt Signed-off-by: Daniel Lezcano --- arch/arm/mach-shmobile/Kconfig | 1 + drivers/clocksource/Kconfig | 7 + drivers/clocksource/Makefile | 1 + drivers/clocksource/renesas-ostm.c | 265 +++++++++++++++++++++++++++++++++++++ 4 files changed, 274 insertions(+) create mode 100644 drivers/clocksource/renesas-ostm.c diff --git a/arch/arm/mach-shmobile/Kconfig b/arch/arm/mach-shmobile/Kconfig index 2bb4b09..ad7d604 100644 --- a/arch/arm/mach-shmobile/Kconfig +++ b/arch/arm/mach-shmobile/Kconfig @@ -57,6 +57,7 @@ config ARCH_R7S72100 select PM select PM_GENERIC_DOMAINS select SYS_SUPPORTS_SH_MTU2 + select RENESAS_OSTM config ARCH_R8A73A4 bool "R-Mobile APE6 (R8A73A40)" diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index afef0e8..4002d6d 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -484,6 +484,13 @@ config SH_TIMER_MTU2 Timer Pulse Unit 2 (MTU2) hardware available on SoCs from Renesas. This hardware comes with 16 bit-timer registers. +config RENESAS_OSTM + bool "Renesas OSTM timer driver" if COMPILE_TEST + depends on GENERIC_CLOCKEVENTS + select CLKSRC_MMIO + help + Enables the support for the Renesas OSTM. + config SH_TIMER_TMU bool "Renesas TMU timer driver" if COMPILE_TEST depends on GENERIC_CLOCKEVENTS diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index dbbee80..d227d13 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -9,6 +9,7 @@ obj-$(CONFIG_CS5535_CLOCK_EVENT_SRC) += cs5535-clockevt.o obj-$(CONFIG_CLKSRC_JCORE_PIT) += jcore-pit.o obj-$(CONFIG_SH_TIMER_CMT) += sh_cmt.o obj-$(CONFIG_SH_TIMER_MTU2) += sh_mtu2.o +obj-$(CONFIG_RENESAS_OSTM) += renesas-ostm.o obj-$(CONFIG_SH_TIMER_TMU) += sh_tmu.o obj-$(CONFIG_EM_TIMER_STI) += em_sti.o obj-$(CONFIG_CLKBLD_I8253) += i8253.o diff --git a/drivers/clocksource/renesas-ostm.c b/drivers/clocksource/renesas-ostm.c new file mode 100644 index 0000000..c76f576 --- /dev/null +++ b/drivers/clocksource/renesas-ostm.c @@ -0,0 +1,265 @@ +/* + * Renesas Timer Support - OSTM + * + * Copyright (C) 2017 Renesas Electronics America, Inc. + * Copyright (C) 2017 Chris Brandt + * + * 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 + * + * 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 +#include +#include +#include +#include +#include +#include + +/* + * The OSTM contains independent channels. + * The first OSTM channel probed will be set up as a free running + * clocksource. Additionally we will use this clocksource for the system + * schedule timer sched_clock(). + * + * The second (or more) channel probed will be set up as an interrupt + * driven clock event. + */ + +struct ostm_device { + void __iomem *base; + unsigned long ticks_per_jiffy; + struct clock_event_device ced; +}; + +static void __iomem *system_clock; /* For sched_clock() */ + +/* OSTM REGISTERS */ +#define OSTM_CMP 0x000 /* RW,32 */ +#define OSTM_CNT 0x004 /* R,32 */ +#define OSTM_TE 0x010 /* R,8 */ +#define OSTM_TS 0x014 /* W,8 */ +#define OSTM_TT 0x018 /* W,8 */ +#define OSTM_CTL 0x020 /* RW,8 */ + +#define TE 0x01 +#define TS 0x01 +#define TT 0x01 +#define CTL_PERIODIC 0x00 +#define CTL_ONESHOT 0x02 +#define CTL_FREERUN 0x02 + +static struct ostm_device *ced_to_ostm(struct clock_event_device *ced) +{ + return container_of(ced, struct ostm_device, ced); +} + +static void ostm_timer_stop(struct ostm_device *ostm) +{ + if (readb(ostm->base + OSTM_TE) & TE) { + writeb(TT, ostm->base + OSTM_TT); + + /* + * Read back the register simply to confirm the write operation + * has completed since I/O writes can sometimes get queued by + * the bus architecture. + */ + while (readb(ostm->base + OSTM_TE) & TE) + ; + } +} + +static int __init ostm_init_clksrc(struct ostm_device *ostm, unsigned long rate) +{ + /* + * irq not used (clock sources don't use interrupts) + */ + + ostm_timer_stop(ostm); + + writel(0, ostm->base + OSTM_CMP); + writeb(CTL_FREERUN, ostm->base + OSTM_CTL); + writeb(TS, ostm->base + OSTM_TS); + + return clocksource_mmio_init(ostm->base + OSTM_CNT, + "ostm", rate, + 300, 32, clocksource_mmio_readl_up); +} + +static u64 notrace ostm_read_sched_clock(void) +{ + return readl(system_clock); +} + +static void __init ostm_init_sched_clock(struct ostm_device *ostm, + unsigned long rate) +{ + system_clock = ostm->base + OSTM_CNT; + sched_clock_register(ostm_read_sched_clock, 32, rate); +} + +static int ostm_clock_event_next(unsigned long delta, + struct clock_event_device *ced) +{ + struct ostm_device *ostm = ced_to_ostm(ced); + + ostm_timer_stop(ostm); + + writel(delta, ostm->base + OSTM_CMP); + writeb(CTL_ONESHOT, ostm->base + OSTM_CTL); + writeb(TS, ostm->base + OSTM_TS); + + return 0; +} + +static int ostm_shutdown(struct clock_event_device *ced) +{ + struct ostm_device *ostm = ced_to_ostm(ced); + + ostm_timer_stop(ostm); + + return 0; +} +static int ostm_set_periodic(struct clock_event_device *ced) +{ + struct ostm_device *ostm = ced_to_ostm(ced); + + if (clockevent_state_oneshot(ced) || clockevent_state_periodic(ced)) + ostm_timer_stop(ostm); + + writel(ostm->ticks_per_jiffy - 1, ostm->base + OSTM_CMP); + writeb(CTL_PERIODIC, ostm->base + OSTM_CTL); + writeb(TS, ostm->base + OSTM_TS); + + return 0; +} + +static int ostm_set_oneshot(struct clock_event_device *ced) +{ + struct ostm_device *ostm = ced_to_ostm(ced); + + ostm_timer_stop(ostm); + + return 0; +} + +static irqreturn_t ostm_timer_interrupt(int irq, void *dev_id) +{ + struct ostm_device *ostm = dev_id; + + if (clockevent_state_oneshot(&ostm->ced)) + ostm_timer_stop(ostm); + + /* notify clockevent layer */ + if (ostm->ced.event_handler) + ostm->ced.event_handler(&ostm->ced); + + return IRQ_HANDLED; +} + +static int __init ostm_init_clkevt(struct ostm_device *ostm, int irq, + unsigned long rate) +{ + struct clock_event_device *ced = &ostm->ced; + int ret = -ENXIO; + + ret = request_irq(irq, ostm_timer_interrupt, + IRQF_TIMER | IRQF_IRQPOLL, + "ostm", ostm); + if (ret) { + pr_err("ostm: failed to request irq\n"); + return ret; + } + + ced->name = "ostm"; + ced->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC; + ced->set_state_shutdown = ostm_shutdown; + ced->set_state_periodic = ostm_set_periodic; + ced->set_state_oneshot = ostm_set_oneshot; + ced->set_next_event = ostm_clock_event_next; + ced->shift = 32; + ced->rating = 300; + ced->cpumask = cpumask_of(0); + clockevents_config_and_register(ced, rate, 0xf, 0xffffffff); + + return 0; +} + +static int __init ostm_init(struct device_node *np) +{ + struct ostm_device *ostm; + int ret = -EFAULT; + struct clk *ostm_clk = NULL; + int irq; + unsigned long rate; + + ostm = kzalloc(sizeof(*ostm), GFP_KERNEL); + if (!ostm) + return -ENOMEM; + + ostm->base = of_iomap(np, 0); + if (!ostm->base) { + pr_err("ostm: failed to remap I/O memory\n"); + goto err; + } + + irq = irq_of_parse_and_map(np, 0); + if (irq < 0) { + pr_err("ostm: Failed to get irq\n"); + goto err; + } + + ostm_clk = of_clk_get(np, 0); + if (IS_ERR(ostm_clk)) { + pr_err("ostm: Failed to get clock\n"); + ostm_clk = NULL; + goto err; + } + + ret = clk_prepare_enable(ostm_clk); + if (ret) { + pr_err("ostm: Failed to enable clock\n"); + goto err; + } + + rate = clk_get_rate(ostm_clk); + ostm->ticks_per_jiffy = (rate + HZ / 2) / HZ; + + /* + * First probed device will be used as system clocksource. Any + * additional devices will be used as clock events. + */ + if (!system_clock) { + ret = ostm_init_clksrc(ostm, rate); + + if (!ret) { + ostm_init_sched_clock(ostm, rate); + pr_info("ostm: used for clocksource\n"); + } + + } else { + ret = ostm_init_clkevt(ostm, irq, rate); + + if (!ret) + pr_info("ostm: used for clock events\n"); + } + +err: + if (ret) { + clk_disable_unprepare(ostm_clk); + iounmap(ostm->base); + kfree(ostm); + return ret; + } + + return 0; +} + +CLOCKSOURCE_OF_DECLARE(ostm, "renesas,ostm", ostm_init);