diff options
Diffstat (limited to 'arch/arm/plat-nomadik/timer.c')
| -rw-r--r-- | arch/arm/plat-nomadik/timer.c | 186 |
1 files changed, 0 insertions, 186 deletions
diff --git a/arch/arm/plat-nomadik/timer.c b/arch/arm/plat-nomadik/timer.c deleted file mode 100644 index aedf9c1d645..00000000000 --- a/arch/arm/plat-nomadik/timer.c +++ /dev/null @@ -1,186 +0,0 @@ -/* - * linux/arch/arm/plat-nomadik/timer.c - * - * Copyright (C) 2008 STMicroelectronics - * Copyright (C) 2010 Alessandro Rubini - * - * 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 <linux/init.h> -#include <linux/interrupt.h> -#include <linux/irq.h> -#include <linux/io.h> -#include <linux/clockchips.h> -#include <linux/clk.h> -#include <linux/jiffies.h> -#include <linux/err.h> -#include <asm/mach/time.h> - -#include <plat/mtu.h> - -void __iomem *mtu_base; /* ssigned by machine code */ - -/* - * Kernel assumes that sched_clock can be called early - * but the MTU may not yet be initialized. - */ -static cycle_t nmdk_read_timer_dummy(struct clocksource *cs) -{ - return 0; -} - -/* clocksource: MTU decrements, so we negate the value being read. */ -static cycle_t nmdk_read_timer(struct clocksource *cs) -{ - return -readl(mtu_base + MTU_VAL(0)); -} - -static struct clocksource nmdk_clksrc = { - .name = "mtu_0", - .rating = 200, - .read = nmdk_read_timer_dummy, - .mask = CLOCKSOURCE_MASK(32), - .flags = CLOCK_SOURCE_IS_CONTINUOUS, -}; - -/* - * Override the global weak sched_clock symbol with this - * local implementation which uses the clocksource to get some - * better resolution when scheduling the kernel. We accept that - * this wraps around for now, since it is just a relative time - * stamp. (Inspired by OMAP implementation.) - */ -unsigned long long notrace sched_clock(void) -{ - return clocksource_cyc2ns(nmdk_clksrc.read( - &nmdk_clksrc), - nmdk_clksrc.mult, - nmdk_clksrc.shift); -} - -/* Clockevent device: use one-shot mode */ -static void nmdk_clkevt_mode(enum clock_event_mode mode, - struct clock_event_device *dev) -{ - u32 cr; - - switch (mode) { - case CLOCK_EVT_MODE_PERIODIC: - pr_err("%s: periodic mode not supported\n", __func__); - break; - case CLOCK_EVT_MODE_ONESHOT: - /* Load highest value, enable device, enable interrupts */ - cr = readl(mtu_base + MTU_CR(1)); - writel(0, mtu_base + MTU_LR(1)); - writel(cr | MTU_CRn_ENA, mtu_base + MTU_CR(1)); - writel(1 << 1, mtu_base + MTU_IMSC); - break; - case CLOCK_EVT_MODE_SHUTDOWN: - case CLOCK_EVT_MODE_UNUSED: - /* disable irq */ - writel(0, mtu_base + MTU_IMSC); - /* disable timer */ - cr = readl(mtu_base + MTU_CR(1)); - cr &= ~MTU_CRn_ENA; - writel(cr, mtu_base + MTU_CR(1)); - /* load some high default value */ - writel(0xffffffff, mtu_base + MTU_LR(1)); - break; - case CLOCK_EVT_MODE_RESUME: - break; - } -} - -static int nmdk_clkevt_next(unsigned long evt, struct clock_event_device *ev) -{ - /* writing the value has immediate effect */ - writel(evt, mtu_base + MTU_LR(1)); - return 0; -} - -static struct clock_event_device nmdk_clkevt = { - .name = "mtu_1", - .features = CLOCK_EVT_FEAT_ONESHOT, - .rating = 200, - .set_mode = nmdk_clkevt_mode, - .set_next_event = nmdk_clkevt_next, -}; - -/* - * IRQ Handler for timer 1 of the MTU block. - */ -static irqreturn_t nmdk_timer_interrupt(int irq, void *dev_id) -{ - struct clock_event_device *evdev = dev_id; - - writel(1 << 1, mtu_base + MTU_ICR); /* Interrupt clear reg */ - evdev->event_handler(evdev); - return IRQ_HANDLED; -} - -static struct irqaction nmdk_timer_irq = { - .name = "Nomadik Timer Tick", - .flags = IRQF_DISABLED | IRQF_TIMER, - .handler = nmdk_timer_interrupt, - .dev_id = &nmdk_clkevt, -}; - -void __init nmdk_timer_init(void) -{ - unsigned long rate; - struct clk *clk0; - u32 cr = MTU_CRn_32BITS; - - clk0 = clk_get_sys("mtu0", NULL); - BUG_ON(IS_ERR(clk0)); - - clk_enable(clk0); - - /* - * Tick rate is 2.4MHz for Nomadik and 2.4Mhz, 100MHz or 133 MHz - * for ux500. - * Use a divide-by-16 counter if the tick rate is more than 32MHz. - * At 32 MHz, the timer (with 32 bit counter) can be programmed - * to wake-up at a max 127s a head in time. Dividing a 2.4 MHz timer - * with 16 gives too low timer resolution. - */ - rate = clk_get_rate(clk0); - if (rate > 32000000) { - rate /= 16; - cr |= MTU_CRn_PRESCALE_16; - } else { - cr |= MTU_CRn_PRESCALE_1; - } - clocksource_calc_mult_shift(&nmdk_clksrc, rate, MTU_MIN_RANGE); - - /* Timer 0 is the free running clocksource */ - writel(cr, mtu_base + MTU_CR(0)); - writel(0, mtu_base + MTU_LR(0)); - writel(0, mtu_base + MTU_BGLR(0)); - writel(cr | MTU_CRn_ENA, mtu_base + MTU_CR(0)); - - /* Now the scheduling clock is ready */ - nmdk_clksrc.read = nmdk_read_timer; - - if (clocksource_register(&nmdk_clksrc)) - pr_err("timer: failed to initialize clock source %s\n", - nmdk_clksrc.name); - - /* Timer 1 is used for events */ - - clockevents_calc_mult_shift(&nmdk_clkevt, rate, MTU_MIN_RANGE); - - writel(cr | MTU_CRn_ONESHOT, mtu_base + MTU_CR(1)); /* off, currently */ - - nmdk_clkevt.max_delta_ns = - clockevent_delta2ns(0xffffffff, &nmdk_clkevt); - nmdk_clkevt.min_delta_ns = - clockevent_delta2ns(0x00000002, &nmdk_clkevt); - nmdk_clkevt.cpumask = cpumask_of(0); - - /* Register irq and clockevents */ - setup_irq(IRQ_MTU0, &nmdk_timer_irq); - clockevents_register_device(&nmdk_clkevt); -} |