diff options
author | Sudeep Holla <sudeep.holla@arm.com> | 2015-05-18 16:29:40 +0100 |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-06-02 09:58:18 +0100 |
commit | 0b7402dce445ba0d11401c2cb806e8fc260c9e49 (patch) | |
tree | 0874f7fb02dd4707840eece7ade0b61628041ae6 /drivers/clocksource/timer-sp804.c | |
parent | 1e5f0519f4cbf8b8830b88039e16222f186a4ab4 (diff) | |
download | blackbird-op-linux-0b7402dce445ba0d11401c2cb806e8fc260c9e49.tar.gz blackbird-op-linux-0b7402dce445ba0d11401c2cb806e8fc260c9e49.zip |
ARM: 8366/1: move Dual-Timer SP804 driver to drivers/clocksource
The ARM Dual-Timer SP804 module is peripheral found not only on ARM32
platforms but also on ARM64 platforms.
This patch moves the driver out of arch/arm to driver/clocksource
so that it can be used on ARM64 platforms also.
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Olof Johansson <olof@lixom.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'drivers/clocksource/timer-sp804.c')
-rw-r--r-- | drivers/clocksource/timer-sp804.c | 310 |
1 files changed, 310 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-sp804.c b/drivers/clocksource/timer-sp804.c new file mode 100644 index 000000000000..ca02503f17d1 --- /dev/null +++ b/drivers/clocksource/timer-sp804.c @@ -0,0 +1,310 @@ +/* + * linux/drivers/clocksource/timer-sp.c + * + * Copyright (C) 1999 - 2003 ARM Limited + * Copyright (C) 2000 Deep Blue Solutions Ltd + * + * 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, or + * (at your option) any later version. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#include <linux/clk.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/sched_clock.h> + +#include <clocksource/timer-sp804.h> + +#include "timer-sp.h" + +static long __init sp804_get_clock_rate(struct clk *clk) +{ + long rate; + int err; + + err = clk_prepare(clk); + if (err) { + pr_err("sp804: clock failed to prepare: %d\n", err); + clk_put(clk); + return err; + } + + err = clk_enable(clk); + if (err) { + pr_err("sp804: clock failed to enable: %d\n", err); + clk_unprepare(clk); + clk_put(clk); + return err; + } + + rate = clk_get_rate(clk); + if (rate < 0) { + pr_err("sp804: clock failed to get rate: %ld\n", rate); + clk_disable(clk); + clk_unprepare(clk); + clk_put(clk); + } + + return rate; +} + +static void __iomem *sched_clock_base; + +static u64 notrace sp804_read(void) +{ + return ~readl_relaxed(sched_clock_base + TIMER_VALUE); +} + +void __init sp804_timer_disable(void __iomem *base) +{ + writel(0, base + TIMER_CTRL); +} + +void __init __sp804_clocksource_and_sched_clock_init(void __iomem *base, + const char *name, + struct clk *clk, + int use_sched_clock) +{ + long rate; + + if (!clk) { + clk = clk_get_sys("sp804", name); + if (IS_ERR(clk)) { + pr_err("sp804: clock not found: %d\n", + (int)PTR_ERR(clk)); + return; + } + } + + rate = sp804_get_clock_rate(clk); + + if (rate < 0) + return; + + /* setup timer 0 as free-running clocksource */ + writel(0, base + TIMER_CTRL); + writel(0xffffffff, base + TIMER_LOAD); + writel(0xffffffff, base + TIMER_VALUE); + writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC, + base + TIMER_CTRL); + + clocksource_mmio_init(base + TIMER_VALUE, name, + rate, 200, 32, clocksource_mmio_readl_down); + + if (use_sched_clock) { + sched_clock_base = base; + sched_clock_register(sp804_read, 32, rate); + } +} + + +static void __iomem *clkevt_base; +static unsigned long clkevt_reload; + +/* + * IRQ handler for the timer + */ +static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *evt = dev_id; + + /* clear the interrupt */ + writel(1, clkevt_base + TIMER_INTCLR); + + evt->event_handler(evt); + + return IRQ_HANDLED; +} + +static void sp804_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE; + + writel(ctrl, clkevt_base + TIMER_CTRL); + + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + writel(clkevt_reload, clkevt_base + TIMER_LOAD); + ctrl |= TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE; + break; + + case CLOCK_EVT_MODE_ONESHOT: + /* period set, and timer enabled in 'next_event' hook */ + ctrl |= TIMER_CTRL_ONESHOT; + break; + + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + default: + break; + } + + writel(ctrl, clkevt_base + TIMER_CTRL); +} + +static int sp804_set_next_event(unsigned long next, + struct clock_event_device *evt) +{ + unsigned long ctrl = readl(clkevt_base + TIMER_CTRL); + + writel(next, clkevt_base + TIMER_LOAD); + writel(ctrl | TIMER_CTRL_ENABLE, clkevt_base + TIMER_CTRL); + + return 0; +} + +static struct clock_event_device sp804_clockevent = { + .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT | + CLOCK_EVT_FEAT_DYNIRQ, + .set_mode = sp804_set_mode, + .set_next_event = sp804_set_next_event, + .rating = 300, +}; + +static struct irqaction sp804_timer_irq = { + .name = "timer", + .flags = IRQF_TIMER | IRQF_IRQPOLL, + .handler = sp804_timer_interrupt, + .dev_id = &sp804_clockevent, +}; + +void __init __sp804_clockevents_init(void __iomem *base, unsigned int irq, struct clk *clk, const char *name) +{ + struct clock_event_device *evt = &sp804_clockevent; + long rate; + + if (!clk) + clk = clk_get_sys("sp804", name); + if (IS_ERR(clk)) { + pr_err("sp804: %s clock not found: %d\n", name, + (int)PTR_ERR(clk)); + return; + } + + rate = sp804_get_clock_rate(clk); + if (rate < 0) + return; + + clkevt_base = base; + clkevt_reload = DIV_ROUND_CLOSEST(rate, HZ); + evt->name = name; + evt->irq = irq; + evt->cpumask = cpu_possible_mask; + + writel(0, base + TIMER_CTRL); + + setup_irq(irq, &sp804_timer_irq); + clockevents_config_and_register(evt, rate, 0xf, 0xffffffff); +} + +static void __init sp804_of_init(struct device_node *np) +{ + static bool initialized = false; + void __iomem *base; + int irq; + u32 irq_num = 0; + struct clk *clk1, *clk2; + const char *name = of_get_property(np, "compatible", NULL); + + base = of_iomap(np, 0); + if (WARN_ON(!base)) + return; + + /* Ensure timers are disabled */ + writel(0, base + TIMER_CTRL); + writel(0, base + TIMER_2_BASE + TIMER_CTRL); + + if (initialized || !of_device_is_available(np)) + goto err; + + clk1 = of_clk_get(np, 0); + if (IS_ERR(clk1)) + clk1 = NULL; + + /* Get the 2nd clock if the timer has 3 timer clocks */ + if (of_count_phandle_with_args(np, "clocks", "#clock-cells") == 3) { + clk2 = of_clk_get(np, 1); + if (IS_ERR(clk2)) { + pr_err("sp804: %s clock not found: %d\n", np->name, + (int)PTR_ERR(clk2)); + clk2 = NULL; + } + } else + clk2 = clk1; + + irq = irq_of_parse_and_map(np, 0); + if (irq <= 0) + goto err; + + of_property_read_u32(np, "arm,sp804-has-irq", &irq_num); + if (irq_num == 2) { + __sp804_clockevents_init(base + TIMER_2_BASE, irq, clk2, name); + __sp804_clocksource_and_sched_clock_init(base, name, clk1, 1); + } else { + __sp804_clockevents_init(base, irq, clk1 , name); + __sp804_clocksource_and_sched_clock_init(base + TIMER_2_BASE, + name, clk2, 1); + } + initialized = true; + + return; +err: + iounmap(base); +} +CLOCKSOURCE_OF_DECLARE(sp804, "arm,sp804", sp804_of_init); + +static void __init integrator_cp_of_init(struct device_node *np) +{ + static int init_count = 0; + void __iomem *base; + int irq; + const char *name = of_get_property(np, "compatible", NULL); + struct clk *clk; + + base = of_iomap(np, 0); + if (WARN_ON(!base)) + return; + clk = of_clk_get(np, 0); + if (WARN_ON(IS_ERR(clk))) + return; + + /* Ensure timer is disabled */ + writel(0, base + TIMER_CTRL); + + if (init_count == 2 || !of_device_is_available(np)) + goto err; + + if (!init_count) + __sp804_clocksource_and_sched_clock_init(base, name, clk, 0); + else { + irq = irq_of_parse_and_map(np, 0); + if (irq <= 0) + goto err; + + __sp804_clockevents_init(base, irq, clk, name); + } + + init_count++; + return; +err: + iounmap(base); +} +CLOCKSOURCE_OF_DECLARE(intcp, "arm,integrator-cp-timer", integrator_cp_of_init); |