|
|
@@ -1,161 +0,0 @@
|
|
|
-/*
|
|
|
- * Copyright (C) 2005-2013 Imagination Technologies Ltd.
|
|
|
- *
|
|
|
- * 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.
|
|
|
- *
|
|
|
- * 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, see <http://www.gnu.org/licenses/>.
|
|
|
- *
|
|
|
- *
|
|
|
- * Support for Meta per-thread timers.
|
|
|
- *
|
|
|
- * Meta hardware threads have 2 timers. The background timer (TXTIMER) is used
|
|
|
- * as a free-running time base (hz clocksource), and the interrupt timer
|
|
|
- * (TXTIMERI) is used for the timer interrupt (clock event). Both counters
|
|
|
- * traditionally count at approximately 1MHz.
|
|
|
- */
|
|
|
-
|
|
|
-#include <clocksource/metag_generic.h>
|
|
|
-#include <linux/cpu.h>
|
|
|
-#include <linux/errno.h>
|
|
|
-#include <linux/sched.h>
|
|
|
-#include <linux/kernel.h>
|
|
|
-#include <linux/param.h>
|
|
|
-#include <linux/time.h>
|
|
|
-#include <linux/init.h>
|
|
|
-#include <linux/proc_fs.h>
|
|
|
-#include <linux/clocksource.h>
|
|
|
-#include <linux/clockchips.h>
|
|
|
-#include <linux/interrupt.h>
|
|
|
-
|
|
|
-#include <asm/clock.h>
|
|
|
-#include <asm/hwthread.h>
|
|
|
-#include <asm/core_reg.h>
|
|
|
-#include <asm/metag_mem.h>
|
|
|
-#include <asm/tbx.h>
|
|
|
-
|
|
|
-#define HARDWARE_FREQ 1000000 /* 1MHz */
|
|
|
-#define HARDWARE_DIV 1 /* divide by 1 = 1MHz clock */
|
|
|
-#define HARDWARE_TO_NS_SHIFT 10 /* convert ticks to ns */
|
|
|
-
|
|
|
-static unsigned int hwtimer_freq = HARDWARE_FREQ;
|
|
|
-static DEFINE_PER_CPU(struct clock_event_device, local_clockevent);
|
|
|
-static DEFINE_PER_CPU(char [11], local_clockevent_name);
|
|
|
-
|
|
|
-static int metag_timer_set_next_event(unsigned long delta,
|
|
|
- struct clock_event_device *dev)
|
|
|
-{
|
|
|
- __core_reg_set(TXTIMERI, -delta);
|
|
|
- return 0;
|
|
|
-}
|
|
|
-
|
|
|
-static u64 metag_clocksource_read(struct clocksource *cs)
|
|
|
-{
|
|
|
- return __core_reg_get(TXTIMER);
|
|
|
-}
|
|
|
-
|
|
|
-static struct clocksource clocksource_metag = {
|
|
|
- .name = "META",
|
|
|
- .rating = 200,
|
|
|
- .mask = CLOCKSOURCE_MASK(32),
|
|
|
- .read = metag_clocksource_read,
|
|
|
- .flags = CLOCK_SOURCE_IS_CONTINUOUS,
|
|
|
-};
|
|
|
-
|
|
|
-static irqreturn_t metag_timer_interrupt(int irq, void *dummy)
|
|
|
-{
|
|
|
- struct clock_event_device *evt = this_cpu_ptr(&local_clockevent);
|
|
|
-
|
|
|
- evt->event_handler(evt);
|
|
|
-
|
|
|
- return IRQ_HANDLED;
|
|
|
-}
|
|
|
-
|
|
|
-static struct irqaction metag_timer_irq = {
|
|
|
- .name = "META core timer",
|
|
|
- .handler = metag_timer_interrupt,
|
|
|
- .flags = IRQF_TIMER | IRQF_IRQPOLL | IRQF_PERCPU,
|
|
|
-};
|
|
|
-
|
|
|
-unsigned long long sched_clock(void)
|
|
|
-{
|
|
|
- unsigned long long ticks = __core_reg_get(TXTIMER);
|
|
|
- return ticks << HARDWARE_TO_NS_SHIFT;
|
|
|
-}
|
|
|
-
|
|
|
-static int arch_timer_starting_cpu(unsigned int cpu)
|
|
|
-{
|
|
|
- unsigned int txdivtime;
|
|
|
- struct clock_event_device *clk = &per_cpu(local_clockevent, cpu);
|
|
|
- char *name = per_cpu(local_clockevent_name, cpu);
|
|
|
-
|
|
|
- txdivtime = __core_reg_get(TXDIVTIME);
|
|
|
-
|
|
|
- txdivtime &= ~TXDIVTIME_DIV_BITS;
|
|
|
- txdivtime |= (HARDWARE_DIV & TXDIVTIME_DIV_BITS);
|
|
|
-
|
|
|
- __core_reg_set(TXDIVTIME, txdivtime);
|
|
|
-
|
|
|
- sprintf(name, "META %d", cpu);
|
|
|
- clk->name = name;
|
|
|
- clk->features = CLOCK_EVT_FEAT_ONESHOT,
|
|
|
-
|
|
|
- clk->rating = 200,
|
|
|
- clk->shift = 12,
|
|
|
- clk->irq = tbisig_map(TBID_SIGNUM_TRT),
|
|
|
- clk->set_next_event = metag_timer_set_next_event,
|
|
|
-
|
|
|
- clk->mult = div_sc(hwtimer_freq, NSEC_PER_SEC, clk->shift);
|
|
|
- clk->max_delta_ns = clockevent_delta2ns(0x7fffffff, clk);
|
|
|
- clk->max_delta_ticks = 0x7fffffff;
|
|
|
- clk->min_delta_ns = clockevent_delta2ns(0xf, clk);
|
|
|
- clk->min_delta_ticks = 0xf;
|
|
|
- clk->cpumask = cpumask_of(cpu);
|
|
|
-
|
|
|
- clockevents_register_device(clk);
|
|
|
-
|
|
|
- /*
|
|
|
- * For all non-boot CPUs we need to synchronize our free
|
|
|
- * running clock (TXTIMER) with the boot CPU's clock.
|
|
|
- *
|
|
|
- * While this won't be accurate, it should be close enough.
|
|
|
- */
|
|
|
- if (cpu) {
|
|
|
- unsigned int thread0 = cpu_2_hwthread_id[0];
|
|
|
- unsigned long val;
|
|
|
-
|
|
|
- val = core_reg_read(TXUCT_ID, TXTIMER_REGNUM, thread0);
|
|
|
- __core_reg_set(TXTIMER, val);
|
|
|
- }
|
|
|
- return 0;
|
|
|
-}
|
|
|
-
|
|
|
-int __init metag_generic_timer_init(void)
|
|
|
-{
|
|
|
- /*
|
|
|
- * On Meta 2 SoCs, the actual frequency of the timer is based on the
|
|
|
- * Meta core clock speed divided by an integer, so it is only
|
|
|
- * approximately 1MHz. Calculating the real frequency here drastically
|
|
|
- * reduces clock skew on these SoCs.
|
|
|
- */
|
|
|
-#ifdef CONFIG_METAG_META21
|
|
|
- hwtimer_freq = get_coreclock() / (metag_in32(EXPAND_TIMER_DIV) + 1);
|
|
|
-#endif
|
|
|
- pr_info("Timer frequency: %u Hz\n", hwtimer_freq);
|
|
|
-
|
|
|
- clocksource_register_hz(&clocksource_metag, hwtimer_freq);
|
|
|
-
|
|
|
- setup_irq(tbisig_map(TBID_SIGNUM_TRT), &metag_timer_irq);
|
|
|
-
|
|
|
- /* Hook cpu boot to configure the CPU's timers */
|
|
|
- return cpuhp_setup_state(CPUHP_AP_METAG_TIMER_STARTING,
|
|
|
- "clockevents/metag:starting",
|
|
|
- arch_timer_starting_cpu, NULL);
|
|
|
-}
|
James Hogan