Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756130Ab3EYLJe (ORCPT ); Sat, 25 May 2013 07:09:34 -0400 Received: from mail-pa0-f51.google.com ([209.85.220.51]:59139 "EHLO mail-pa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756074Ab3EYLJa (ORCPT ); Sat, 25 May 2013 07:09:30 -0400 From: Daniel Tang To: linux-arm-kernel@lists.infradead.org, "linux@arm.linux.org.uk ARM Linux" Cc: Daniel Tang , Linus Walleij , Arnd Bergmann , "fabian@ritter-vogt.de Vogt" , Lionel Debroux , linux-kernel@vger.kernel.org, John Stultz , Thomas Gleixner Subject: [RFC PATCHv4 4/6] clocksource: TI-Nspire timer support Date: Sat, 25 May 2013 21:08:05 +1000 Message-Id: <1369480087-24786-5-git-send-email-dt.tangr@gmail.com> X-Mailer: git-send-email 1.8.1.3 In-Reply-To: <1369480087-24786-1-git-send-email-dt.tangr@gmail.com> References: <1369480087-24786-1-git-send-email-dt.tangr@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8620 Lines: 307 Add clocksource and clockevent driver for the TI-Nspire. Signed-off-by: Daniel Tang --- .../devicetree/bindings/timer/lsi,zevio-timer.txt | 33 +++ drivers/clocksource/Makefile | 1 + drivers/clocksource/zevio-timer.c | 231 +++++++++++++++++++++ 3 files changed, 265 insertions(+) create mode 100644 Documentation/devicetree/bindings/timer/lsi,zevio-timer.txt create mode 100644 drivers/clocksource/zevio-timer.c diff --git a/Documentation/devicetree/bindings/timer/lsi,zevio-timer.txt b/Documentation/devicetree/bindings/timer/lsi,zevio-timer.txt new file mode 100644 index 0000000..b2d07ad --- /dev/null +++ b/Documentation/devicetree/bindings/timer/lsi,zevio-timer.txt @@ -0,0 +1,33 @@ +TI-NSPIRE timer + +Required properties: + +- compatible : should be "lsi,zevio-timer". +- reg : The physical base address and size of the timer (always first). +- clocks: phandle to the source clock. + +Optional properties: + +- interrupts : The interrupt number of the first timer. +- reg : The interrupt acknowledgement registers + (always after timer base address) + +If any of the optional properties are not given, the timer is added as a +clock-source only. + +Example: + +timer { + compatible = "lsi,zevio-timer"; + reg = <0x900D0000 0x1000>, <0x900A0020 0x8>; + interrupts = <19>; + clocks = <&timer_clk>; +}; + +Example (no clock-events): + +timer { + compatible = "lsi,zevio-timer"; + reg = <0x900D0000 0x1000>; + clocks = <&timer_clk>; +}; diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 8d979c7..293f86e 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -22,6 +22,7 @@ obj-$(CONFIG_ARCH_PRIMA2) += timer-prima2.o obj-$(CONFIG_SUN4I_TIMER) += sun4i_timer.o obj-$(CONFIG_ARCH_TEGRA) += tegra20_timer.o obj-$(CONFIG_VT8500_TIMER) += vt8500_timer.o +obj-$(CONFIG_ARCH_NSPIRE) += zevio-timer.o obj-$(CONFIG_ARCH_BCM) += bcm_kona_timer.o obj-$(CONFIG_CADENCE_TTC_TIMER) += cadence_ttc_timer.o obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exynos_mct.o diff --git a/drivers/clocksource/zevio-timer.c b/drivers/clocksource/zevio-timer.c new file mode 100644 index 0000000..c6d7f03 --- /dev/null +++ b/drivers/clocksource/zevio-timer.c @@ -0,0 +1,231 @@ +/* + * linux/drivers/clocksource/zevio-timer.c + * + * Copyright (C) 2013 Daniel Tang + * + * 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. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define IO_CURRENT_VAL 0x00 +#define IO_DIVIDER 0x04 +#define IO_CONTROL 0x08 + +#define IO_TIMER1 0x00 +#define IO_TIMER2 0x0C + +#define IO_MATCH_BEGIN 0x18 +#define IO_MATCH(x) (IO_MATCH_BEGIN + ((x)<<2)) + +#define IO_INTR_STS 0x00 +#define IO_INTR_ACK 0x00 +#define IO_INTR_MSK 0x04 + +#define CNTL_STOP_TIMER (1<<4) +#define CNTL_RUN_TIMER (0<<4) + +#define CNTL_INC (1<<3) +#define CNTL_DEC (0<<3) + +#define CNTL_TOZERO 0 +#define CNTL_MATCH(x) ((x) + 1) +#define CNTL_FOREVER 7 + +/* There are 6 match registers but we only use one. */ +#define TIMER_MATCH 0 + +#define TIMER_INTR_MSK (1<<(TIMER_MATCH)) +#define TIMER_INTR_ALL 0x3F + +struct zevio_timer { + void __iomem *base; + void __iomem *timer1, *timer2; + void __iomem *interrupt_regs; + + int irqnr; + + struct clk *clk; + struct clock_event_device clkevt; + struct irqaction clkevt_irq; + + char clocksource_name[64]; + char clockevent_name[64]; +}; + +static int zevio_timer_set_event(unsigned long delta, + struct clock_event_device *dev) +{ + unsigned long flags; + struct zevio_timer *timer = container_of(dev, + struct zevio_timer, + clkevt); + + local_irq_save(flags); + + writel(delta, timer->timer1 + IO_CURRENT_VAL); + writel(CNTL_RUN_TIMER | CNTL_DEC | CNTL_MATCH(TIMER_MATCH), + timer->timer1 + IO_CONTROL); + + local_irq_restore(flags); + + return 0; +} + +static void zevio_timer_set_mode(enum clock_event_mode mode, + struct clock_event_device *dev) +{ + unsigned long flags; + struct zevio_timer *timer = container_of(dev, + struct zevio_timer, + clkevt); + + local_irq_save(flags); + + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + /* Unsupported */ + break; + case CLOCK_EVT_MODE_RESUME: + case CLOCK_EVT_MODE_ONESHOT: + /* Enable timer interrupts */ + writel(TIMER_INTR_MSK, timer->interrupt_regs + IO_INTR_MSK); + writel(TIMER_INTR_ALL, timer->interrupt_regs + IO_INTR_ACK); + dev->mode = mode; + break; + case CLOCK_EVT_MODE_SHUTDOWN: + case CLOCK_EVT_MODE_UNUSED: + /* Disable timer interrupts */ + writel(0, timer->interrupt_regs + IO_INTR_MSK); + writel(TIMER_INTR_ALL, timer->interrupt_regs + IO_INTR_ACK); + /* Stop timer */ + writel(CNTL_STOP_TIMER, timer->timer1 + IO_CONTROL); + dev->mode = mode; + break; + } + + local_irq_restore(flags); +} + +static irqreturn_t zevio_timer_interrupt(int irq, void *dev_id) +{ + struct zevio_timer *timer = dev_id; + u32 intr; + + intr = readl(timer->interrupt_regs + IO_INTR_ACK); + if (!(intr & TIMER_INTR_MSK)) + return IRQ_NONE; + + writel(TIMER_INTR_MSK, timer->interrupt_regs + IO_INTR_ACK); + writel(CNTL_STOP_TIMER, timer->timer1 + IO_CONTROL); + + if (timer->clkevt.event_handler) + timer->clkevt.event_handler(&timer->clkevt); + + return IRQ_HANDLED; +} + +static int __init zevio_timer_add(struct device_node *node) +{ + struct zevio_timer *timer; + struct resource res; + int ret; + + timer = kzalloc(sizeof(*timer), GFP_ATOMIC); + if (!timer) + return -ENOMEM; + + timer->base = of_iomap(node, 0); + if (!timer->base) { + ret = -EINVAL; + goto error_free; + } + timer->timer1 = timer->base + IO_TIMER1; + timer->timer2 = timer->base + IO_TIMER2; + + timer->clk = of_clk_get(node, 0); + if (IS_ERR(timer->clk)) { + ret = PTR_ERR(timer->clk); + pr_err("Timer clock not found! (error %d)\n", ret); + goto error_unmap; + } + + timer->interrupt_regs = of_iomap(node, 1); + timer->irqnr = irq_of_parse_and_map(node, 0); + + of_address_to_resource(node, 0, &res); + scnprintf(timer->clocksource_name, sizeof(timer->clocksource_name), + "%llx.%s_clocksource", + (unsigned long long)res.start, node->name); + + scnprintf(timer->clockevent_name, sizeof(timer->clockevent_name), + "%llx.%s_clockevent", + (unsigned long long)res.start, node->name); + + if (timer->interrupt_regs && timer->irqnr) { + timer->clkevt.name = timer->clockevent_name; + timer->clkevt.set_next_event = zevio_timer_set_event; + timer->clkevt.set_mode = zevio_timer_set_mode; + timer->clkevt.rating = 200; + timer->clkevt.cpumask = cpu_all_mask; + timer->clkevt.features = + CLOCK_EVT_FEAT_ONESHOT; + + writel(CNTL_STOP_TIMER, timer->timer1 + IO_CONTROL); + writel(0, timer->timer1 + IO_DIVIDER); + + /* Start with timer interrupts disabled */ + writel(0, timer->interrupt_regs + IO_INTR_MSK); + writel(TIMER_INTR_ALL, timer->interrupt_regs + IO_INTR_ACK); + + /* Interrupt to occur when timer value matches 0 */ + writel(0, timer->base + IO_MATCH(TIMER_MATCH)); + + timer->clkevt_irq.name = timer->clockevent_name; + timer->clkevt_irq.handler = zevio_timer_interrupt; + timer->clkevt_irq.dev_id = timer; + timer->clkevt_irq.flags = + IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL; + + setup_irq(timer->irqnr, &timer->clkevt_irq); + + clockevents_config_and_register(&timer->clkevt, + clk_get_rate(timer->clk), 0x0001, 0xffff); + pr_info("Added %s as clockevent\n", timer->clockevent_name); + } + + writel(CNTL_STOP_TIMER, timer->timer2 + IO_CONTROL); + writel(0, timer->timer2 + IO_CURRENT_VAL); + writel(0, timer->timer2 + IO_DIVIDER); + writel(CNTL_RUN_TIMER | CNTL_FOREVER | CNTL_INC, + timer->timer2 + IO_CONTROL); + + clocksource_mmio_init(timer->timer2 + IO_CURRENT_VAL, + timer->clocksource_name, + clk_get_rate(timer->clk), + 200, 16, + clocksource_mmio_readw_up); + + pr_info("Added %s as clocksource\n", timer->clocksource_name); + + return 0; +error_unmap: + iounmap(timer->base); +error_free: + kfree(timer); + return ret; +} + +CLOCKSOURCE_OF_DECLARE(zevio_timer, "lsi,zevio-timer", zevio_timer_add); -- 1.8.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/