diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-14 17:48:14 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-14 17:48:14 -0700 |
commit | 2ca7d674d7ab2220707b2ada0b690c0e7c95e7ac (patch) | |
tree | 9c0927ed1d540e5fd704c1f82689870786514655 /arch/arm/mach-nomadik/timer.c | |
parent | 2195d2818c37bdf263865f1e9effccdd9fc5f9d4 (diff) | |
parent | 87d721ad7a37b7650dd710c88dd5c6a5bf9fe996 (diff) |
Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (257 commits)
[ARM] Update mach-types
ARM: 5636/1: Move vendor enum to AMBA include
ARM: Fix pfn_valid() for sparse memory
[ARM] orion5x: Add LaCie NAS 2Big Network support
[ARM] pxa/sharpsl_pm: zaurus c3000 aka spitz: fix resume
ARM: 5686/1: at91: Correct AC97 reset line in at91sam9263ek board
ARM: 5640/1: This patch modifies the support of AC97 on the at91sam9263 ek board
ARM: 5689/1: Update default config of HP Jornada 700-series machines
ARM: 5691/1: fix cache aliasing issues between kmap() and kmap_atomic() with highmem
ARM: 5688/1: ks8695_serial: disable_irq() lockup
ARM: 5687/1: fix an oops with highmem
ARM: 5684/1: Add nuc960 platform to w90x900
ARM: 5683/1: Add nuc950 platform to w90x900
ARM: 5682/1: Add cpu.c and dev.c and modify some files of w90p910 platform
ARM: 5626/1: add suspend/resume functions to amba-pl011 serial driver
ARM: 5625/1: fix hard coded 4K resource size in amba bus detection
MMC: MMCI: convert realview MMC to use gpiolib
ARM: 5685/1: Make MMCI driver compile without gpiolib
ARM: implement highpte
ARM: Show FIQ in /proc/interrupts on CONFIG_FIQ
...
Fix up trivial conflict in arch/arm/kernel/signal.c.
It was due to the TIF_NOTIFY_RESUME addition in commit d0420c83f ("KEYS:
Extend TIF_NOTIFY_RESUME to (almost) all architectures") and follow-ups.
Diffstat (limited to 'arch/arm/mach-nomadik/timer.c')
-rw-r--r-- | arch/arm/mach-nomadik/timer.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/arch/arm/mach-nomadik/timer.c b/arch/arm/mach-nomadik/timer.c new file mode 100644 index 00000000000..d1738e7061d --- /dev/null +++ b/arch/arm/mach-nomadik/timer.c @@ -0,0 +1,164 @@ +/* + * linux/arch/arm/mach-nomadik/timer.c + * + * Copyright (C) 2008 STMicroelectronics + * Copyright (C) 2009 Alessandro Rubini, somewhat based on at91sam926x + * + * 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/jiffies.h> +#include <asm/mach/time.h> +#include <mach/mtu.h> + +#define TIMER_CTRL 0x80 /* No divisor */ +#define TIMER_PERIODIC 0x40 +#define TIMER_SZ32BIT 0x02 + +/* Initial value for SRC control register: all timers use MXTAL/8 source */ +#define SRC_CR_INIT_MASK 0x00007fff +#define SRC_CR_INIT_VAL 0x2aaa8000 + +static u32 nmdk_count; /* accumulated count */ +static u32 nmdk_cycle; /* write-once */ +static __iomem void *mtu_base; + +/* + * clocksource: the MTU device is a decrementing counters, so we negate + * the value being read. + */ +static cycle_t nmdk_read_timer(struct clocksource *cs) +{ + u32 count = readl(mtu_base + MTU_VAL(0)); + return nmdk_count + nmdk_cycle - count; + +} + +static struct clocksource nmdk_clksrc = { + .name = "mtu_0", + .rating = 120, + .read = nmdk_read_timer, + .shift = 20, + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +/* + * Clockevent device: currently only periodic mode is supported + */ +static void nmdk_clkevt_mode(enum clock_event_mode mode, + struct clock_event_device *dev) +{ + unsigned long flags; + + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + /* enable interrupts -- and count current value? */ + raw_local_irq_save(flags); + writel(readl(mtu_base + MTU_IMSC) | 1, mtu_base + MTU_IMSC); + raw_local_irq_restore(flags); + break; + case CLOCK_EVT_MODE_ONESHOT: + BUG(); /* Not supported, yet */ + /* FALLTHROUGH */ + case CLOCK_EVT_MODE_SHUTDOWN: + case CLOCK_EVT_MODE_UNUSED: + /* disable irq */ + raw_local_irq_save(flags); + writel(readl(mtu_base + MTU_IMSC) & ~1, mtu_base + MTU_IMSC); + raw_local_irq_restore(flags); + break; + case CLOCK_EVT_MODE_RESUME: + break; + } +} + +static struct clock_event_device nmdk_clkevt = { + .name = "mtu_0", + .features = CLOCK_EVT_FEAT_PERIODIC, + .shift = 32, + .rating = 100, + .set_mode = nmdk_clkevt_mode, +}; + +/* + * IRQ Handler for the timer 0 of the MTU block. The irq is not shared + * as we are the only users of mtu0 by now. + */ +static irqreturn_t nmdk_timer_interrupt(int irq, void *dev_id) +{ + /* ack: "interrupt clear register" */ + writel( 1 << 0, mtu_base + MTU_ICR); + + /* we can't count lost ticks, unfortunately */ + nmdk_count += nmdk_cycle; + nmdk_clkevt.event_handler(&nmdk_clkevt); + + return IRQ_HANDLED; +} + +/* + * Set up timer interrupt, and return the current time in seconds. + */ +static struct irqaction nmdk_timer_irq = { + .name = "Nomadik Timer Tick", + .flags = IRQF_DISABLED | IRQF_TIMER, + .handler = nmdk_timer_interrupt, +}; + +static void nmdk_timer_reset(void) +{ + u32 cr; + + writel(0, mtu_base + MTU_CR(0)); /* off */ + + /* configure load and background-load, and fire it up */ + writel(nmdk_cycle, mtu_base + MTU_LR(0)); + writel(nmdk_cycle, mtu_base + MTU_BGLR(0)); + cr = MTU_CRn_PERIODIC | MTU_CRn_PRESCALE_1 | MTU_CRn_32BITS; + writel(cr, mtu_base + MTU_CR(0)); + writel(cr | MTU_CRn_ENA, mtu_base + MTU_CR(0)); +} + +static void __init nmdk_timer_init(void) +{ + u32 src_cr; + unsigned long rate; + int bits; + + rate = CLOCK_TICK_RATE; /* 2.4MHz */ + nmdk_cycle = (rate + HZ/2) / HZ; + + /* Configure timer sources in "system reset controller" ctrl reg */ + src_cr = readl(io_p2v(NOMADIK_SRC_BASE)); + src_cr &= SRC_CR_INIT_MASK; + src_cr |= SRC_CR_INIT_VAL; + writel(src_cr, io_p2v(NOMADIK_SRC_BASE)); + + /* Save global pointer to mtu, used by functions above */ + mtu_base = io_p2v(NOMADIK_MTU0_BASE); + + /* Init the timer and register clocksource */ + nmdk_timer_reset(); + + nmdk_clksrc.mult = clocksource_hz2mult(rate, nmdk_clksrc.shift); + bits = 8*sizeof(nmdk_count); + nmdk_clksrc.mask = CLOCKSOURCE_MASK(bits); + + clocksource_register(&nmdk_clksrc); + + /* Register irq and clockevents */ + setup_irq(IRQ_MTU0, &nmdk_timer_irq); + nmdk_clkevt.mult = div_sc(rate, NSEC_PER_SEC, nmdk_clkevt.shift); + nmdk_clkevt.cpumask = cpumask_of(0); + clockevents_register_device(&nmdk_clkevt); +} + +struct sys_timer nomadik_timer = { + .init = nmdk_timer_init, +}; |