diff options
Diffstat (limited to 'arch/mips/loongson64/common/cs5536/cs5536_mfgpt.c')
| -rw-r--r-- | arch/mips/loongson64/common/cs5536/cs5536_mfgpt.c | 207 |
1 files changed, 0 insertions, 207 deletions
diff --git a/arch/mips/loongson64/common/cs5536/cs5536_mfgpt.c b/arch/mips/loongson64/common/cs5536/cs5536_mfgpt.c deleted file mode 100644 index 30af1b7c7529..000000000000 --- a/arch/mips/loongson64/common/cs5536/cs5536_mfgpt.c +++ /dev/null @@ -1,207 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * CS5536 General timer functions - * - * Copyright (C) 2007 Lemote Inc. & Institute of Computing Technology - * Author: Yanhua, yanh@lemote.com - * - * Copyright (C) 2009 Lemote Inc. - * Author: Wu zhangjin, wuzhangjin@gmail.com - * - * Reference: AMD Geode(TM) CS5536 Companion Device Data Book - */ - -#include <linux/io.h> -#include <linux/init.h> -#include <linux/export.h> -#include <linux/jiffies.h> -#include <linux/spinlock.h> -#include <linux/interrupt.h> -#include <linux/clockchips.h> - -#include <asm/time.h> - -#include <cs5536/cs5536_mfgpt.h> - -static DEFINE_RAW_SPINLOCK(mfgpt_lock); - -static u32 mfgpt_base; - -/* - * Initialize the MFGPT timer. - * - * This is also called after resume to bring the MFGPT into operation again. - */ - -/* disable counter */ -void disable_mfgpt0_counter(void) -{ - outw(inw(MFGPT0_SETUP) & 0x7fff, MFGPT0_SETUP); -} -EXPORT_SYMBOL(disable_mfgpt0_counter); - -/* enable counter, comparator2 to event mode, 14.318MHz clock */ -void enable_mfgpt0_counter(void) -{ - outw(0xe310, MFGPT0_SETUP); -} -EXPORT_SYMBOL(enable_mfgpt0_counter); - -static int mfgpt_timer_set_periodic(struct clock_event_device *evt) -{ - raw_spin_lock(&mfgpt_lock); - - outw(COMPARE, MFGPT0_CMP2); /* set comparator2 */ - outw(0, MFGPT0_CNT); /* set counter to 0 */ - enable_mfgpt0_counter(); - - raw_spin_unlock(&mfgpt_lock); - return 0; -} - -static int mfgpt_timer_shutdown(struct clock_event_device *evt) -{ - if (clockevent_state_periodic(evt) || clockevent_state_oneshot(evt)) { - raw_spin_lock(&mfgpt_lock); - disable_mfgpt0_counter(); - raw_spin_unlock(&mfgpt_lock); - } - - return 0; -} - -static struct clock_event_device mfgpt_clockevent = { - .name = "mfgpt", - .features = CLOCK_EVT_FEAT_PERIODIC, - - /* The oneshot mode have very high deviation, don't use it! */ - .set_state_shutdown = mfgpt_timer_shutdown, - .set_state_periodic = mfgpt_timer_set_periodic, - .irq = CS5536_MFGPT_INTR, -}; - -static irqreturn_t timer_interrupt(int irq, void *dev_id) -{ - u32 basehi; - - /* - * get MFGPT base address - * - * NOTE: do not remove me, it's need for the value of mfgpt_base is - * variable - */ - _rdmsr(DIVIL_MSR_REG(DIVIL_LBAR_MFGPT), &basehi, &mfgpt_base); - - /* ack */ - outw(inw(MFGPT0_SETUP) | 0x4000, MFGPT0_SETUP); - - mfgpt_clockevent.event_handler(&mfgpt_clockevent); - - return IRQ_HANDLED; -} - -static struct irqaction irq5 = { - .handler = timer_interrupt, - .flags = IRQF_NOBALANCING | IRQF_TIMER, - .name = "timer" -}; - -/* - * Initialize the conversion factor and the min/max deltas of the clock event - * structure and register the clock event source with the framework. - */ -void __init setup_mfgpt0_timer(void) -{ - u32 basehi; - struct clock_event_device *cd = &mfgpt_clockevent; - unsigned int cpu = smp_processor_id(); - - cd->cpumask = cpumask_of(cpu); - clockevent_set_clock(cd, MFGPT_TICK_RATE); - cd->max_delta_ns = clockevent_delta2ns(0xffff, cd); - cd->max_delta_ticks = 0xffff; - cd->min_delta_ns = clockevent_delta2ns(0xf, cd); - cd->min_delta_ticks = 0xf; - - /* Enable MFGPT0 Comparator 2 Output to the Interrupt Mapper */ - _wrmsr(DIVIL_MSR_REG(MFGPT_IRQ), 0, 0x100); - - /* Enable Interrupt Gate 5 */ - _wrmsr(DIVIL_MSR_REG(PIC_ZSEL_LOW), 0, 0x50000); - - /* get MFGPT base address */ - _rdmsr(DIVIL_MSR_REG(DIVIL_LBAR_MFGPT), &basehi, &mfgpt_base); - - clockevents_register_device(cd); - - setup_irq(CS5536_MFGPT_INTR, &irq5); -} - -/* - * Since the MFGPT overflows every tick, its not very useful - * to just read by itself. So use jiffies to emulate a free - * running counter: - */ -static u64 mfgpt_read(struct clocksource *cs) -{ - unsigned long flags; - int count; - u32 jifs; - static int old_count; - static u32 old_jifs; - - raw_spin_lock_irqsave(&mfgpt_lock, flags); - /* - * Although our caller may have the read side of xtime_lock, - * this is now a seqlock, and we are cheating in this routine - * by having side effects on state that we cannot undo if - * there is a collision on the seqlock and our caller has to - * retry. (Namely, old_jifs and old_count.) So we must treat - * jiffies as volatile despite the lock. We read jiffies - * before latching the timer count to guarantee that although - * the jiffies value might be older than the count (that is, - * the counter may underflow between the last point where - * jiffies was incremented and the point where we latch the - * count), it cannot be newer. - */ - jifs = jiffies; - /* read the count */ - count = inw(MFGPT0_CNT); - - /* - * It's possible for count to appear to go the wrong way for this - * reason: - * - * The timer counter underflows, but we haven't handled the resulting - * interrupt and incremented jiffies yet. - * - * Previous attempts to handle these cases intelligently were buggy, so - * we just do the simple thing now. - */ - if (count < old_count && jifs == old_jifs) - count = old_count; - - old_count = count; - old_jifs = jifs; - - raw_spin_unlock_irqrestore(&mfgpt_lock, flags); - - return (u64) (jifs * COMPARE) + count; -} - -static struct clocksource clocksource_mfgpt = { - .name = "mfgpt", - .rating = 120, /* Functional for real use, but not desired */ - .read = mfgpt_read, - .mask = CLOCKSOURCE_MASK(32), -}; - -int __init init_mfgpt_clocksource(void) -{ - if (num_possible_cpus() > 1) /* MFGPT does not scale! */ - return 0; - - return clocksource_register_hz(&clocksource_mfgpt, MFGPT_TICK_RATE); -} - -arch_initcall(init_mfgpt_clocksource); |