diff options
Diffstat (limited to 'ANDROID_3.4.5/arch/x86/kernel/apb_timer.c')
-rw-r--r-- | ANDROID_3.4.5/arch/x86/kernel/apb_timer.c | 431 |
1 files changed, 0 insertions, 431 deletions
diff --git a/ANDROID_3.4.5/arch/x86/kernel/apb_timer.c b/ANDROID_3.4.5/arch/x86/kernel/apb_timer.c deleted file mode 100644 index afdc3f75..00000000 --- a/ANDROID_3.4.5/arch/x86/kernel/apb_timer.c +++ /dev/null @@ -1,431 +0,0 @@ -/* - * apb_timer.c: Driver for Langwell APB timers - * - * (C) Copyright 2009 Intel Corporation - * Author: Jacob Pan (jacob.jun.pan@intel.com) - * - * 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; version 2 - * of the License. - * - * Note: - * Langwell is the south complex of Intel Moorestown MID platform. There are - * eight external timers in total that can be used by the operating system. - * The timer information, such as frequency and addresses, is provided to the - * OS via SFI tables. - * Timer interrupts are routed via FW/HW emulated IOAPIC independently via - * individual redirection table entries (RTE). - * Unlike HPET, there is no master counter, therefore one of the timers are - * used as clocksource. The overall allocation looks like: - * - timer 0 - NR_CPUs for per cpu timer - * - one timer for clocksource - * - one timer for watchdog driver. - * It is also worth notice that APB timer does not support true one-shot mode, - * free-running mode will be used here to emulate one-shot mode. - * APB timer can also be used as broadcast timer along with per cpu local APIC - * timer, but by default APB timer has higher rating than local APIC timers. - */ - -#include <linux/delay.h> -#include <linux/dw_apb_timer.h> -#include <linux/errno.h> -#include <linux/init.h> -#include <linux/slab.h> -#include <linux/pm.h> -#include <linux/sfi.h> -#include <linux/interrupt.h> -#include <linux/cpu.h> -#include <linux/irq.h> - -#include <asm/fixmap.h> -#include <asm/apb_timer.h> -#include <asm/mrst.h> -#include <asm/time.h> - -#define APBT_CLOCKEVENT_RATING 110 -#define APBT_CLOCKSOURCE_RATING 250 - -#define APBT_CLOCKEVENT0_NUM (0) -#define APBT_CLOCKSOURCE_NUM (2) - -static phys_addr_t apbt_address; -static int apb_timer_block_enabled; -static void __iomem *apbt_virt_address; - -/* - * Common DW APB timer info - */ -static unsigned long apbt_freq; - -struct apbt_dev { - struct dw_apb_clock_event_device *timer; - unsigned int num; - int cpu; - unsigned int irq; - char name[10]; -}; - -static struct dw_apb_clocksource *clocksource_apbt; - -static inline void __iomem *adev_virt_addr(struct apbt_dev *adev) -{ - return apbt_virt_address + adev->num * APBTMRS_REG_SIZE; -} - -static DEFINE_PER_CPU(struct apbt_dev, cpu_apbt_dev); - -#ifdef CONFIG_SMP -static unsigned int apbt_num_timers_used; -#endif - -static inline void apbt_set_mapping(void) -{ - struct sfi_timer_table_entry *mtmr; - int phy_cs_timer_id = 0; - - if (apbt_virt_address) { - pr_debug("APBT base already mapped\n"); - return; - } - mtmr = sfi_get_mtmr(APBT_CLOCKEVENT0_NUM); - if (mtmr == NULL) { - printk(KERN_ERR "Failed to get MTMR %d from SFI\n", - APBT_CLOCKEVENT0_NUM); - return; - } - apbt_address = (phys_addr_t)mtmr->phys_addr; - if (!apbt_address) { - printk(KERN_WARNING "No timer base from SFI, use default\n"); - apbt_address = APBT_DEFAULT_BASE; - } - apbt_virt_address = ioremap_nocache(apbt_address, APBT_MMAP_SIZE); - if (!apbt_virt_address) { - pr_debug("Failed mapping APBT phy address at %lu\n",\ - (unsigned long)apbt_address); - goto panic_noapbt; - } - apbt_freq = mtmr->freq_hz; - sfi_free_mtmr(mtmr); - - /* Now figure out the physical timer id for clocksource device */ - mtmr = sfi_get_mtmr(APBT_CLOCKSOURCE_NUM); - if (mtmr == NULL) - goto panic_noapbt; - - /* Now figure out the physical timer id */ - pr_debug("Use timer %d for clocksource\n", - (int)(mtmr->phys_addr & 0xff) / APBTMRS_REG_SIZE); - phy_cs_timer_id = (unsigned int)(mtmr->phys_addr & 0xff) / - APBTMRS_REG_SIZE; - - clocksource_apbt = dw_apb_clocksource_init(APBT_CLOCKSOURCE_RATING, - "apbt0", apbt_virt_address + phy_cs_timer_id * - APBTMRS_REG_SIZE, apbt_freq); - return; - -panic_noapbt: - panic("Failed to setup APB system timer\n"); - -} - -static inline void apbt_clear_mapping(void) -{ - iounmap(apbt_virt_address); - apbt_virt_address = NULL; -} - -/* - * APBT timer interrupt enable / disable - */ -static inline int is_apbt_capable(void) -{ - return apbt_virt_address ? 1 : 0; -} - -static int __init apbt_clockevent_register(void) -{ - struct sfi_timer_table_entry *mtmr; - struct apbt_dev *adev = &__get_cpu_var(cpu_apbt_dev); - - mtmr = sfi_get_mtmr(APBT_CLOCKEVENT0_NUM); - if (mtmr == NULL) { - printk(KERN_ERR "Failed to get MTMR %d from SFI\n", - APBT_CLOCKEVENT0_NUM); - return -ENODEV; - } - - adev->num = smp_processor_id(); - adev->timer = dw_apb_clockevent_init(smp_processor_id(), "apbt0", - mrst_timer_options == MRST_TIMER_LAPIC_APBT ? - APBT_CLOCKEVENT_RATING - 100 : APBT_CLOCKEVENT_RATING, - adev_virt_addr(adev), 0, apbt_freq); - /* Firmware does EOI handling for us. */ - adev->timer->eoi = NULL; - - if (mrst_timer_options == MRST_TIMER_LAPIC_APBT) { - global_clock_event = &adev->timer->ced; - printk(KERN_DEBUG "%s clockevent registered as global\n", - global_clock_event->name); - } - - dw_apb_clockevent_register(adev->timer); - - sfi_free_mtmr(mtmr); - return 0; -} - -#ifdef CONFIG_SMP - -static void apbt_setup_irq(struct apbt_dev *adev) -{ - /* timer0 irq has been setup early */ - if (adev->irq == 0) - return; - - irq_modify_status(adev->irq, 0, IRQ_MOVE_PCNTXT); - irq_set_affinity(adev->irq, cpumask_of(adev->cpu)); - /* APB timer irqs are set up as mp_irqs, timer is edge type */ - __irq_set_handler(adev->irq, handle_edge_irq, 0, "edge"); -} - -/* Should be called with per cpu */ -void apbt_setup_secondary_clock(void) -{ - struct apbt_dev *adev; - int cpu; - - /* Don't register boot CPU clockevent */ - cpu = smp_processor_id(); - if (!cpu) - return; - - adev = &__get_cpu_var(cpu_apbt_dev); - if (!adev->timer) { - adev->timer = dw_apb_clockevent_init(cpu, adev->name, - APBT_CLOCKEVENT_RATING, adev_virt_addr(adev), - adev->irq, apbt_freq); - adev->timer->eoi = NULL; - } else { - dw_apb_clockevent_resume(adev->timer); - } - - printk(KERN_INFO "Registering CPU %d clockevent device %s, cpu %08x\n", - cpu, adev->name, adev->cpu); - - apbt_setup_irq(adev); - dw_apb_clockevent_register(adev->timer); - - return; -} - -/* - * this notify handler process CPU hotplug events. in case of S0i3, nonboot - * cpus are disabled/enabled frequently, for performance reasons, we keep the - * per cpu timer irq registered so that we do need to do free_irq/request_irq. - * - * TODO: it might be more reliable to directly disable percpu clockevent device - * without the notifier chain. currently, cpu 0 may get interrupts from other - * cpu timers during the offline process due to the ordering of notification. - * the extra interrupt is harmless. - */ -static int apbt_cpuhp_notify(struct notifier_block *n, - unsigned long action, void *hcpu) -{ - unsigned long cpu = (unsigned long)hcpu; - struct apbt_dev *adev = &per_cpu(cpu_apbt_dev, cpu); - - switch (action & 0xf) { - case CPU_DEAD: - dw_apb_clockevent_pause(adev->timer); - if (system_state == SYSTEM_RUNNING) { - pr_debug("skipping APBT CPU %lu offline\n", cpu); - } else if (adev) { - pr_debug("APBT clockevent for cpu %lu offline\n", cpu); - dw_apb_clockevent_stop(adev->timer); - } - break; - default: - pr_debug("APBT notified %lu, no action\n", action); - } - return NOTIFY_OK; -} - -static __init int apbt_late_init(void) -{ - if (mrst_timer_options == MRST_TIMER_LAPIC_APBT || - !apb_timer_block_enabled) - return 0; - /* This notifier should be called after workqueue is ready */ - hotcpu_notifier(apbt_cpuhp_notify, -20); - return 0; -} -fs_initcall(apbt_late_init); -#else - -void apbt_setup_secondary_clock(void) {} - -#endif /* CONFIG_SMP */ - -static int apbt_clocksource_register(void) -{ - u64 start, now; - cycle_t t1; - - /* Start the counter, use timer 2 as source, timer 0/1 for event */ - dw_apb_clocksource_start(clocksource_apbt); - - /* Verify whether apbt counter works */ - t1 = dw_apb_clocksource_read(clocksource_apbt); - rdtscll(start); - - /* - * We don't know the TSC frequency yet, but waiting for - * 200000 TSC cycles is safe: - * 4 GHz == 50us - * 1 GHz == 200us - */ - do { - rep_nop(); - rdtscll(now); - } while ((now - start) < 200000UL); - - /* APBT is the only always on clocksource, it has to work! */ - if (t1 == dw_apb_clocksource_read(clocksource_apbt)) - panic("APBT counter not counting. APBT disabled\n"); - - dw_apb_clocksource_register(clocksource_apbt); - - return 0; -} - -/* - * Early setup the APBT timer, only use timer 0 for booting then switch to - * per CPU timer if possible. - * returns 1 if per cpu apbt is setup - * returns 0 if no per cpu apbt is chosen - * panic if set up failed, this is the only platform timer on Moorestown. - */ -void __init apbt_time_init(void) -{ -#ifdef CONFIG_SMP - int i; - struct sfi_timer_table_entry *p_mtmr; - unsigned int percpu_timer; - struct apbt_dev *adev; -#endif - - if (apb_timer_block_enabled) - return; - apbt_set_mapping(); - if (!apbt_virt_address) - goto out_noapbt; - /* - * Read the frequency and check for a sane value, for ESL model - * we extend the possible clock range to allow time scaling. - */ - - if (apbt_freq < APBT_MIN_FREQ || apbt_freq > APBT_MAX_FREQ) { - pr_debug("APBT has invalid freq 0x%lx\n", apbt_freq); - goto out_noapbt; - } - if (apbt_clocksource_register()) { - pr_debug("APBT has failed to register clocksource\n"); - goto out_noapbt; - } - if (!apbt_clockevent_register()) - apb_timer_block_enabled = 1; - else { - pr_debug("APBT has failed to register clockevent\n"); - goto out_noapbt; - } -#ifdef CONFIG_SMP - /* kernel cmdline disable apb timer, so we will use lapic timers */ - if (mrst_timer_options == MRST_TIMER_LAPIC_APBT) { - printk(KERN_INFO "apbt: disabled per cpu timer\n"); - return; - } - pr_debug("%s: %d CPUs online\n", __func__, num_online_cpus()); - if (num_possible_cpus() <= sfi_mtimer_num) { - percpu_timer = 1; - apbt_num_timers_used = num_possible_cpus(); - } else { - percpu_timer = 0; - apbt_num_timers_used = 1; - } - pr_debug("%s: %d APB timers used\n", __func__, apbt_num_timers_used); - - /* here we set up per CPU timer data structure */ - for (i = 0; i < apbt_num_timers_used; i++) { - adev = &per_cpu(cpu_apbt_dev, i); - adev->num = i; - adev->cpu = i; - p_mtmr = sfi_get_mtmr(i); - if (p_mtmr) - adev->irq = p_mtmr->irq; - else - printk(KERN_ERR "Failed to get timer for cpu %d\n", i); - snprintf(adev->name, sizeof(adev->name) - 1, "apbt%d", i); - } -#endif - - return; - -out_noapbt: - apbt_clear_mapping(); - apb_timer_block_enabled = 0; - panic("failed to enable APB timer\n"); -} - -/* called before apb_timer_enable, use early map */ -unsigned long apbt_quick_calibrate(void) -{ - int i, scale; - u64 old, new; - cycle_t t1, t2; - unsigned long khz = 0; - u32 loop, shift; - - apbt_set_mapping(); - dw_apb_clocksource_start(clocksource_apbt); - - /* check if the timer can count down, otherwise return */ - old = dw_apb_clocksource_read(clocksource_apbt); - i = 10000; - while (--i) { - if (old != dw_apb_clocksource_read(clocksource_apbt)) - break; - } - if (!i) - goto failed; - - /* count 16 ms */ - loop = (apbt_freq / 1000) << 4; - - /* restart the timer to ensure it won't get to 0 in the calibration */ - dw_apb_clocksource_start(clocksource_apbt); - - old = dw_apb_clocksource_read(clocksource_apbt); - old += loop; - - t1 = __native_read_tsc(); - - do { - new = dw_apb_clocksource_read(clocksource_apbt); - } while (new < old); - - t2 = __native_read_tsc(); - - shift = 5; - if (unlikely(loop >> shift == 0)) { - printk(KERN_INFO - "APBT TSC calibration failed, not enough resolution\n"); - return 0; - } - scale = (int)div_u64((t2 - t1), loop >> shift); - khz = (scale * (apbt_freq / 1000)) >> shift; - printk(KERN_INFO "TSC freq calculated by APB timer is %lu khz\n", khz); - return khz; -failed: - return 0; -} |