diff options
Diffstat (limited to 'ANDROID_3.4.5/arch/x86/kernel/hpet.c')
| -rw-r--r-- | ANDROID_3.4.5/arch/x86/kernel/hpet.c | 1209 |
1 files changed, 0 insertions, 1209 deletions
diff --git a/ANDROID_3.4.5/arch/x86/kernel/hpet.c b/ANDROID_3.4.5/arch/x86/kernel/hpet.c deleted file mode 100644 index ad0de0c2..00000000 --- a/ANDROID_3.4.5/arch/x86/kernel/hpet.c +++ /dev/null @@ -1,1209 +0,0 @@ -#include <linux/clocksource.h> -#include <linux/clockchips.h> -#include <linux/interrupt.h> -#include <linux/export.h> -#include <linux/delay.h> -#include <linux/errno.h> -#include <linux/i8253.h> -#include <linux/slab.h> -#include <linux/hpet.h> -#include <linux/init.h> -#include <linux/cpu.h> -#include <linux/pm.h> -#include <linux/io.h> - -#include <asm/fixmap.h> -#include <asm/hpet.h> -#include <asm/time.h> - -#define HPET_MASK CLOCKSOURCE_MASK(32) - -/* FSEC = 10^-15 - NSEC = 10^-9 */ -#define FSEC_PER_NSEC 1000000L - -#define HPET_DEV_USED_BIT 2 -#define HPET_DEV_USED (1 << HPET_DEV_USED_BIT) -#define HPET_DEV_VALID 0x8 -#define HPET_DEV_FSB_CAP 0x1000 -#define HPET_DEV_PERI_CAP 0x2000 - -#define HPET_MIN_CYCLES 128 -#define HPET_MIN_PROG_DELTA (HPET_MIN_CYCLES + (HPET_MIN_CYCLES >> 1)) - -/* - * HPET address is set in acpi/boot.c, when an ACPI entry exists - */ -unsigned long hpet_address; -u8 hpet_blockid; /* OS timer block num */ -u8 hpet_msi_disable; - -#ifdef CONFIG_PCI_MSI -static unsigned long hpet_num_timers; -#endif -static void __iomem *hpet_virt_address; - -struct hpet_dev { - struct clock_event_device evt; - unsigned int num; - int cpu; - unsigned int irq; - unsigned int flags; - char name[10]; -}; - -inline struct hpet_dev *EVT_TO_HPET_DEV(struct clock_event_device *evtdev) -{ - return container_of(evtdev, struct hpet_dev, evt); -} - -inline unsigned int hpet_readl(unsigned int a) -{ - return readl(hpet_virt_address + a); -} - -static inline void hpet_writel(unsigned int d, unsigned int a) -{ - writel(d, hpet_virt_address + a); -} - -#ifdef CONFIG_X86_64 -#include <asm/pgtable.h> -#endif - -static inline void hpet_set_mapping(void) -{ - hpet_virt_address = ioremap_nocache(hpet_address, HPET_MMAP_SIZE); -#ifdef CONFIG_X86_64 - __set_fixmap(VSYSCALL_HPET, hpet_address, PAGE_KERNEL_VVAR_NOCACHE); -#endif -} - -static inline void hpet_clear_mapping(void) -{ - iounmap(hpet_virt_address); - hpet_virt_address = NULL; -} - -/* - * HPET command line enable / disable - */ -static int boot_hpet_disable; -int hpet_force_user; -static int hpet_verbose; - -static int __init hpet_setup(char *str) -{ - if (str) { - if (!strncmp("disable", str, 7)) - boot_hpet_disable = 1; - if (!strncmp("force", str, 5)) - hpet_force_user = 1; - if (!strncmp("verbose", str, 7)) - hpet_verbose = 1; - } - return 1; -} -__setup("hpet=", hpet_setup); - -static int __init disable_hpet(char *str) -{ - boot_hpet_disable = 1; - return 1; -} -__setup("nohpet", disable_hpet); - -static inline int is_hpet_capable(void) -{ - return !boot_hpet_disable && hpet_address; -} - -/* - * HPET timer interrupt enable / disable - */ -static int hpet_legacy_int_enabled; - -/** - * is_hpet_enabled - check whether the hpet timer interrupt is enabled - */ -int is_hpet_enabled(void) -{ - return is_hpet_capable() && hpet_legacy_int_enabled; -} -EXPORT_SYMBOL_GPL(is_hpet_enabled); - -static void _hpet_print_config(const char *function, int line) -{ - u32 i, timers, l, h; - printk(KERN_INFO "hpet: %s(%d):\n", function, line); - l = hpet_readl(HPET_ID); - h = hpet_readl(HPET_PERIOD); - timers = ((l & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT) + 1; - printk(KERN_INFO "hpet: ID: 0x%x, PERIOD: 0x%x\n", l, h); - l = hpet_readl(HPET_CFG); - h = hpet_readl(HPET_STATUS); - printk(KERN_INFO "hpet: CFG: 0x%x, STATUS: 0x%x\n", l, h); - l = hpet_readl(HPET_COUNTER); - h = hpet_readl(HPET_COUNTER+4); - printk(KERN_INFO "hpet: COUNTER_l: 0x%x, COUNTER_h: 0x%x\n", l, h); - - for (i = 0; i < timers; i++) { - l = hpet_readl(HPET_Tn_CFG(i)); - h = hpet_readl(HPET_Tn_CFG(i)+4); - printk(KERN_INFO "hpet: T%d: CFG_l: 0x%x, CFG_h: 0x%x\n", - i, l, h); - l = hpet_readl(HPET_Tn_CMP(i)); - h = hpet_readl(HPET_Tn_CMP(i)+4); - printk(KERN_INFO "hpet: T%d: CMP_l: 0x%x, CMP_h: 0x%x\n", - i, l, h); - l = hpet_readl(HPET_Tn_ROUTE(i)); - h = hpet_readl(HPET_Tn_ROUTE(i)+4); - printk(KERN_INFO "hpet: T%d ROUTE_l: 0x%x, ROUTE_h: 0x%x\n", - i, l, h); - } -} - -#define hpet_print_config() \ -do { \ - if (hpet_verbose) \ - _hpet_print_config(__FUNCTION__, __LINE__); \ -} while (0) - -/* - * When the hpet driver (/dev/hpet) is enabled, we need to reserve - * timer 0 and timer 1 in case of RTC emulation. - */ -#ifdef CONFIG_HPET - -static void hpet_reserve_msi_timers(struct hpet_data *hd); - -static void hpet_reserve_platform_timers(unsigned int id) -{ - struct hpet __iomem *hpet = hpet_virt_address; - struct hpet_timer __iomem *timer = &hpet->hpet_timers[2]; - unsigned int nrtimers, i; - struct hpet_data hd; - - nrtimers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT) + 1; - - memset(&hd, 0, sizeof(hd)); - hd.hd_phys_address = hpet_address; - hd.hd_address = hpet; - hd.hd_nirqs = nrtimers; - hpet_reserve_timer(&hd, 0); - -#ifdef CONFIG_HPET_EMULATE_RTC - hpet_reserve_timer(&hd, 1); -#endif - - /* - * NOTE that hd_irq[] reflects IOAPIC input pins (LEGACY_8254 - * is wrong for i8259!) not the output IRQ. Many BIOS writers - * don't bother configuring *any* comparator interrupts. - */ - hd.hd_irq[0] = HPET_LEGACY_8254; - hd.hd_irq[1] = HPET_LEGACY_RTC; - - for (i = 2; i < nrtimers; timer++, i++) { - hd.hd_irq[i] = (readl(&timer->hpet_config) & - Tn_INT_ROUTE_CNF_MASK) >> Tn_INT_ROUTE_CNF_SHIFT; - } - - hpet_reserve_msi_timers(&hd); - - hpet_alloc(&hd); - -} -#else -static void hpet_reserve_platform_timers(unsigned int id) { } -#endif - -/* - * Common hpet info - */ -static unsigned long hpet_freq; - -static void hpet_legacy_set_mode(enum clock_event_mode mode, - struct clock_event_device *evt); -static int hpet_legacy_next_event(unsigned long delta, - struct clock_event_device *evt); - -/* - * The hpet clock event device - */ -static struct clock_event_device hpet_clockevent = { - .name = "hpet", - .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, - .set_mode = hpet_legacy_set_mode, - .set_next_event = hpet_legacy_next_event, - .irq = 0, - .rating = 50, -}; - -static void hpet_stop_counter(void) -{ - unsigned long cfg = hpet_readl(HPET_CFG); - cfg &= ~HPET_CFG_ENABLE; - hpet_writel(cfg, HPET_CFG); -} - -static void hpet_reset_counter(void) -{ - hpet_writel(0, HPET_COUNTER); - hpet_writel(0, HPET_COUNTER + 4); -} - -static void hpet_start_counter(void) -{ - unsigned int cfg = hpet_readl(HPET_CFG); - cfg |= HPET_CFG_ENABLE; - hpet_writel(cfg, HPET_CFG); -} - -static void hpet_restart_counter(void) -{ - hpet_stop_counter(); - hpet_reset_counter(); - hpet_start_counter(); -} - -static void hpet_resume_device(void) -{ - force_hpet_resume(); -} - -static void hpet_resume_counter(struct clocksource *cs) -{ - hpet_resume_device(); - hpet_restart_counter(); -} - -static void hpet_enable_legacy_int(void) -{ - unsigned int cfg = hpet_readl(HPET_CFG); - - cfg |= HPET_CFG_LEGACY; - hpet_writel(cfg, HPET_CFG); - hpet_legacy_int_enabled = 1; -} - -static void hpet_legacy_clockevent_register(void) -{ - /* Start HPET legacy interrupts */ - hpet_enable_legacy_int(); - - /* - * Start hpet with the boot cpu mask and make it - * global after the IO_APIC has been initialized. - */ - hpet_clockevent.cpumask = cpumask_of(smp_processor_id()); - clockevents_config_and_register(&hpet_clockevent, hpet_freq, - HPET_MIN_PROG_DELTA, 0x7FFFFFFF); - global_clock_event = &hpet_clockevent; - printk(KERN_DEBUG "hpet clockevent registered\n"); -} - -static int hpet_setup_msi_irq(unsigned int irq); - -static void hpet_set_mode(enum clock_event_mode mode, - struct clock_event_device *evt, int timer) -{ - unsigned int cfg, cmp, now; - uint64_t delta; - - switch (mode) { - case CLOCK_EVT_MODE_PERIODIC: - hpet_stop_counter(); - delta = ((uint64_t)(NSEC_PER_SEC/HZ)) * evt->mult; - delta >>= evt->shift; - now = hpet_readl(HPET_COUNTER); - cmp = now + (unsigned int) delta; - cfg = hpet_readl(HPET_Tn_CFG(timer)); - /* Make sure we use edge triggered interrupts */ - cfg &= ~HPET_TN_LEVEL; - cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC | - HPET_TN_SETVAL | HPET_TN_32BIT; - hpet_writel(cfg, HPET_Tn_CFG(timer)); - hpet_writel(cmp, HPET_Tn_CMP(timer)); - udelay(1); - /* - * HPET on AMD 81xx needs a second write (with HPET_TN_SETVAL - * cleared) to T0_CMP to set the period. The HPET_TN_SETVAL - * bit is automatically cleared after the first write. - * (See AMD-8111 HyperTransport I/O Hub Data Sheet, - * Publication # 24674) - */ - hpet_writel((unsigned int) delta, HPET_Tn_CMP(timer)); - hpet_start_counter(); - hpet_print_config(); - break; - - case CLOCK_EVT_MODE_ONESHOT: - cfg = hpet_readl(HPET_Tn_CFG(timer)); - cfg &= ~HPET_TN_PERIODIC; - cfg |= HPET_TN_ENABLE | HPET_TN_32BIT; - hpet_writel(cfg, HPET_Tn_CFG(timer)); - break; - - case CLOCK_EVT_MODE_UNUSED: - case CLOCK_EVT_MODE_SHUTDOWN: - cfg = hpet_readl(HPET_Tn_CFG(timer)); - cfg &= ~HPET_TN_ENABLE; - hpet_writel(cfg, HPET_Tn_CFG(timer)); - break; - - case CLOCK_EVT_MODE_RESUME: - if (timer == 0) { - hpet_enable_legacy_int(); - } else { - struct hpet_dev *hdev = EVT_TO_HPET_DEV(evt); - hpet_setup_msi_irq(hdev->irq); - disable_irq(hdev->irq); - irq_set_affinity(hdev->irq, cpumask_of(hdev->cpu)); - enable_irq(hdev->irq); - } - hpet_print_config(); - break; - } -} - -static int hpet_next_event(unsigned long delta, - struct clock_event_device *evt, int timer) -{ - u32 cnt; - s32 res; - - cnt = hpet_readl(HPET_COUNTER); - cnt += (u32) delta; - hpet_writel(cnt, HPET_Tn_CMP(timer)); - - /* - * HPETs are a complete disaster. The compare register is - * based on a equal comparison and neither provides a less - * than or equal functionality (which would require to take - * the wraparound into account) nor a simple count down event - * mode. Further the write to the comparator register is - * delayed internally up to two HPET clock cycles in certain - * chipsets (ATI, ICH9,10). Some newer AMD chipsets have even - * longer delays. We worked around that by reading back the - * compare register, but that required another workaround for - * ICH9,10 chips where the first readout after write can - * return the old stale value. We already had a minimum - * programming delta of 5us enforced, but a NMI or SMI hitting - * between the counter readout and the comparator write can - * move us behind that point easily. Now instead of reading - * the compare register back several times, we make the ETIME - * decision based on the following: Return ETIME if the - * counter value after the write is less than HPET_MIN_CYCLES - * away from the event or if the counter is already ahead of - * the event. The minimum programming delta for the generic - * clockevents code is set to 1.5 * HPET_MIN_CYCLES. - */ - res = (s32)(cnt - hpet_readl(HPET_COUNTER)); - - return res < HPET_MIN_CYCLES ? -ETIME : 0; -} - -static void hpet_legacy_set_mode(enum clock_event_mode mode, - struct clock_event_device *evt) -{ - hpet_set_mode(mode, evt, 0); -} - -static int hpet_legacy_next_event(unsigned long delta, - struct clock_event_device *evt) -{ - return hpet_next_event(delta, evt, 0); -} - -/* - * HPET MSI Support - */ -#ifdef CONFIG_PCI_MSI - -static DEFINE_PER_CPU(struct hpet_dev *, cpu_hpet_dev); -static struct hpet_dev *hpet_devs; - -void hpet_msi_unmask(struct irq_data *data) -{ - struct hpet_dev *hdev = data->handler_data; - unsigned int cfg; - - /* unmask it */ - cfg = hpet_readl(HPET_Tn_CFG(hdev->num)); - cfg |= HPET_TN_FSB; - hpet_writel(cfg, HPET_Tn_CFG(hdev->num)); -} - -void hpet_msi_mask(struct irq_data *data) -{ - struct hpet_dev *hdev = data->handler_data; - unsigned int cfg; - - /* mask it */ - cfg = hpet_readl(HPET_Tn_CFG(hdev->num)); - cfg &= ~HPET_TN_FSB; - hpet_writel(cfg, HPET_Tn_CFG(hdev->num)); -} - -void hpet_msi_write(struct hpet_dev *hdev, struct msi_msg *msg) -{ - hpet_writel(msg->data, HPET_Tn_ROUTE(hdev->num)); - hpet_writel(msg->address_lo, HPET_Tn_ROUTE(hdev->num) + 4); -} - -void hpet_msi_read(struct hpet_dev *hdev, struct msi_msg *msg) -{ - msg->data = hpet_readl(HPET_Tn_ROUTE(hdev->num)); - msg->address_lo = hpet_readl(HPET_Tn_ROUTE(hdev->num) + 4); - msg->address_hi = 0; -} - -static void hpet_msi_set_mode(enum clock_event_mode mode, - struct clock_event_device *evt) -{ - struct hpet_dev *hdev = EVT_TO_HPET_DEV(evt); - hpet_set_mode(mode, evt, hdev->num); -} - -static int hpet_msi_next_event(unsigned long delta, - struct clock_event_device *evt) -{ - struct hpet_dev *hdev = EVT_TO_HPET_DEV(evt); - return hpet_next_event(delta, evt, hdev->num); -} - -static int hpet_setup_msi_irq(unsigned int irq) -{ - if (arch_setup_hpet_msi(irq, hpet_blockid)) { - destroy_irq(irq); - return -EINVAL; - } - return 0; -} - -static int hpet_assign_irq(struct hpet_dev *dev) -{ - unsigned int irq; - - irq = create_irq_nr(0, -1); - if (!irq) - return -EINVAL; - - irq_set_handler_data(irq, dev); - - if (hpet_setup_msi_irq(irq)) - return -EINVAL; - - dev->irq = irq; - return 0; -} - -static irqreturn_t hpet_interrupt_handler(int irq, void *data) -{ - struct hpet_dev *dev = (struct hpet_dev *)data; - struct clock_event_device *hevt = &dev->evt; - - if (!hevt->event_handler) { - printk(KERN_INFO "Spurious HPET timer interrupt on HPET timer %d\n", - dev->num); - return IRQ_HANDLED; - } - - hevt->event_handler(hevt); - return IRQ_HANDLED; -} - -static int hpet_setup_irq(struct hpet_dev *dev) -{ - - if (request_irq(dev->irq, hpet_interrupt_handler, - IRQF_TIMER | IRQF_DISABLED | IRQF_NOBALANCING, - dev->name, dev)) - return -1; - - disable_irq(dev->irq); - irq_set_affinity(dev->irq, cpumask_of(dev->cpu)); - enable_irq(dev->irq); - - printk(KERN_DEBUG "hpet: %s irq %d for MSI\n", - dev->name, dev->irq); - - return 0; -} - -/* This should be called in specific @cpu */ -static void init_one_hpet_msi_clockevent(struct hpet_dev *hdev, int cpu) -{ - struct clock_event_device *evt = &hdev->evt; - - WARN_ON(cpu != smp_processor_id()); - if (!(hdev->flags & HPET_DEV_VALID)) - return; - - if (hpet_setup_msi_irq(hdev->irq)) - return; - - hdev->cpu = cpu; - per_cpu(cpu_hpet_dev, cpu) = hdev; - evt->name = hdev->name; - hpet_setup_irq(hdev); - evt->irq = hdev->irq; - - evt->rating = 110; - evt->features = CLOCK_EVT_FEAT_ONESHOT; - if (hdev->flags & HPET_DEV_PERI_CAP) - evt->features |= CLOCK_EVT_FEAT_PERIODIC; - - evt->set_mode = hpet_msi_set_mode; - evt->set_next_event = hpet_msi_next_event; - evt->cpumask = cpumask_of(hdev->cpu); - - clockevents_config_and_register(evt, hpet_freq, HPET_MIN_PROG_DELTA, - 0x7FFFFFFF); -} - -#ifdef CONFIG_HPET -/* Reserve at least one timer for userspace (/dev/hpet) */ -#define RESERVE_TIMERS 1 -#else -#define RESERVE_TIMERS 0 -#endif - -static void hpet_msi_capability_lookup(unsigned int start_timer) -{ - unsigned int id; - unsigned int num_timers; - unsigned int num_timers_used = 0; - int i; - - if (hpet_msi_disable) - return; - - if (boot_cpu_has(X86_FEATURE_ARAT)) - return; - id = hpet_readl(HPET_ID); - - num_timers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT); - num_timers++; /* Value read out starts from 0 */ - hpet_print_config(); - - hpet_devs = kzalloc(sizeof(struct hpet_dev) * num_timers, GFP_KERNEL); - if (!hpet_devs) - return; - - hpet_num_timers = num_timers; - - for (i = start_timer; i < num_timers - RESERVE_TIMERS; i++) { - struct hpet_dev *hdev = &hpet_devs[num_timers_used]; - unsigned int cfg = hpet_readl(HPET_Tn_CFG(i)); - - /* Only consider HPET timer with MSI support */ - if (!(cfg & HPET_TN_FSB_CAP)) - continue; - - hdev->flags = 0; - if (cfg & HPET_TN_PERIODIC_CAP) - hdev->flags |= HPET_DEV_PERI_CAP; - hdev->num = i; - - sprintf(hdev->name, "hpet%d", i); - if (hpet_assign_irq(hdev)) - continue; - - hdev->flags |= HPET_DEV_FSB_CAP; - hdev->flags |= HPET_DEV_VALID; - num_timers_used++; - if (num_timers_used == num_possible_cpus()) - break; - } - - printk(KERN_INFO "HPET: %d timers in total, %d timers will be used for per-cpu timer\n", - num_timers, num_timers_used); -} - -#ifdef CONFIG_HPET -static void hpet_reserve_msi_timers(struct hpet_data *hd) -{ - int i; - - if (!hpet_devs) - return; - - for (i = 0; i < hpet_num_timers; i++) { - struct hpet_dev *hdev = &hpet_devs[i]; - - if (!(hdev->flags & HPET_DEV_VALID)) - continue; - - hd->hd_irq[hdev->num] = hdev->irq; - hpet_reserve_timer(hd, hdev->num); - } -} -#endif - -static struct hpet_dev *hpet_get_unused_timer(void) -{ - int i; - - if (!hpet_devs) - return NULL; - - for (i = 0; i < hpet_num_timers; i++) { - struct hpet_dev *hdev = &hpet_devs[i]; - - if (!(hdev->flags & HPET_DEV_VALID)) - continue; - if (test_and_set_bit(HPET_DEV_USED_BIT, - (unsigned long *)&hdev->flags)) - continue; - return hdev; - } - return NULL; -} - -struct hpet_work_struct { - struct delayed_work work; - struct completion complete; -}; - -static void hpet_work(struct work_struct *w) -{ - struct hpet_dev *hdev; - int cpu = smp_processor_id(); - struct hpet_work_struct *hpet_work; - - hpet_work = container_of(w, struct hpet_work_struct, work.work); - - hdev = hpet_get_unused_timer(); - if (hdev) - init_one_hpet_msi_clockevent(hdev, cpu); - - complete(&hpet_work->complete); -} - -static int hpet_cpuhp_notify(struct notifier_block *n, - unsigned long action, void *hcpu) -{ - unsigned long cpu = (unsigned long)hcpu; - struct hpet_work_struct work; - struct hpet_dev *hdev = per_cpu(cpu_hpet_dev, cpu); - - switch (action & 0xf) { - case CPU_ONLINE: - INIT_DELAYED_WORK_ONSTACK(&work.work, hpet_work); - init_completion(&work.complete); - /* FIXME: add schedule_work_on() */ - schedule_delayed_work_on(cpu, &work.work, 0); - wait_for_completion(&work.complete); - destroy_timer_on_stack(&work.work.timer); - break; - case CPU_DEAD: - if (hdev) { - free_irq(hdev->irq, hdev); - hdev->flags &= ~HPET_DEV_USED; - per_cpu(cpu_hpet_dev, cpu) = NULL; - } - break; - } - return NOTIFY_OK; -} -#else - -static int hpet_setup_msi_irq(unsigned int irq) -{ - return 0; -} -static void hpet_msi_capability_lookup(unsigned int start_timer) -{ - return; -} - -#ifdef CONFIG_HPET -static void hpet_reserve_msi_timers(struct hpet_data *hd) -{ - return; -} -#endif - -static int hpet_cpuhp_notify(struct notifier_block *n, - unsigned long action, void *hcpu) -{ - return NOTIFY_OK; -} - -#endif - -/* - * Clock source related code - */ -static cycle_t read_hpet(struct clocksource *cs) -{ - return (cycle_t)hpet_readl(HPET_COUNTER); -} - -static struct clocksource clocksource_hpet = { - .name = "hpet", - .rating = 250, - .read = read_hpet, - .mask = HPET_MASK, - .flags = CLOCK_SOURCE_IS_CONTINUOUS, - .resume = hpet_resume_counter, -#ifdef CONFIG_X86_64 - .archdata = { .vclock_mode = VCLOCK_HPET }, -#endif -}; - -static int hpet_clocksource_register(void) -{ - u64 start, now; - cycle_t t1; - - /* Start the counter */ - hpet_restart_counter(); - - /* Verify whether hpet counter works */ - t1 = hpet_readl(HPET_COUNTER); - 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); - - if (t1 == hpet_readl(HPET_COUNTER)) { - printk(KERN_WARNING - "HPET counter not counting. HPET disabled\n"); - return -ENODEV; - } - - clocksource_register_hz(&clocksource_hpet, (u32)hpet_freq); - return 0; -} - -/** - * hpet_enable - Try to setup the HPET timer. Returns 1 on success. - */ -int __init hpet_enable(void) -{ - unsigned long hpet_period; - unsigned int id; - u64 freq; - int i; - - if (!is_hpet_capable()) - return 0; - - hpet_set_mapping(); - - /* - * Read the period and check for a sane value: - */ - hpet_period = hpet_readl(HPET_PERIOD); - - /* - * AMD SB700 based systems with spread spectrum enabled use a - * SMM based HPET emulation to provide proper frequency - * setting. The SMM code is initialized with the first HPET - * register access and takes some time to complete. During - * this time the config register reads 0xffffffff. We check - * for max. 1000 loops whether the config register reads a non - * 0xffffffff value to make sure that HPET is up and running - * before we go further. A counting loop is safe, as the HPET - * access takes thousands of CPU cycles. On non SB700 based - * machines this check is only done once and has no side - * effects. - */ - for (i = 0; hpet_readl(HPET_CFG) == 0xFFFFFFFF; i++) { - if (i == 1000) { - printk(KERN_WARNING - "HPET config register value = 0xFFFFFFFF. " - "Disabling HPET\n"); - goto out_nohpet; - } - } - - if (hpet_period < HPET_MIN_PERIOD || hpet_period > HPET_MAX_PERIOD) - goto out_nohpet; - - /* - * The period is a femto seconds value. Convert it to a - * frequency. - */ - freq = FSEC_PER_SEC; - do_div(freq, hpet_period); - hpet_freq = freq; - - /* - * Read the HPET ID register to retrieve the IRQ routing - * information and the number of channels - */ - id = hpet_readl(HPET_ID); - hpet_print_config(); - -#ifdef CONFIG_HPET_EMULATE_RTC - /* - * The legacy routing mode needs at least two channels, tick timer - * and the rtc emulation channel. - */ - if (!(id & HPET_ID_NUMBER)) - goto out_nohpet; -#endif - - if (hpet_clocksource_register()) - goto out_nohpet; - - if (id & HPET_ID_LEGSUP) { - hpet_legacy_clockevent_register(); - return 1; - } - return 0; - -out_nohpet: - hpet_clear_mapping(); - hpet_address = 0; - return 0; -} - -/* - * Needs to be late, as the reserve_timer code calls kalloc ! - * - * Not a problem on i386 as hpet_enable is called from late_time_init, - * but on x86_64 it is necessary ! - */ -static __init int hpet_late_init(void) -{ - int cpu; - - if (boot_hpet_disable) - return -ENODEV; - - if (!hpet_address) { - if (!force_hpet_address) - return -ENODEV; - - hpet_address = force_hpet_address; - hpet_enable(); - } - - if (!hpet_virt_address) - return -ENODEV; - - if (hpet_readl(HPET_ID) & HPET_ID_LEGSUP) - hpet_msi_capability_lookup(2); - else - hpet_msi_capability_lookup(0); - - hpet_reserve_platform_timers(hpet_readl(HPET_ID)); - hpet_print_config(); - - if (hpet_msi_disable) - return 0; - - if (boot_cpu_has(X86_FEATURE_ARAT)) - return 0; - - for_each_online_cpu(cpu) { - hpet_cpuhp_notify(NULL, CPU_ONLINE, (void *)(long)cpu); - } - - /* This notifier should be called after workqueue is ready */ - hotcpu_notifier(hpet_cpuhp_notify, -20); - - return 0; -} -fs_initcall(hpet_late_init); - -void hpet_disable(void) -{ - if (is_hpet_capable() && hpet_virt_address) { - unsigned int cfg = hpet_readl(HPET_CFG); - - if (hpet_legacy_int_enabled) { - cfg &= ~HPET_CFG_LEGACY; - hpet_legacy_int_enabled = 0; - } - cfg &= ~HPET_CFG_ENABLE; - hpet_writel(cfg, HPET_CFG); - } -} - -#ifdef CONFIG_HPET_EMULATE_RTC - -/* HPET in LegacyReplacement Mode eats up RTC interrupt line. When, HPET - * is enabled, we support RTC interrupt functionality in software. - * RTC has 3 kinds of interrupts: - * 1) Update Interrupt - generate an interrupt, every sec, when RTC clock - * is updated - * 2) Alarm Interrupt - generate an interrupt at a specific time of day - * 3) Periodic Interrupt - generate periodic interrupt, with frequencies - * 2Hz-8192Hz (2Hz-64Hz for non-root user) (all freqs in powers of 2) - * (1) and (2) above are implemented using polling at a frequency of - * 64 Hz. The exact frequency is a tradeoff between accuracy and interrupt - * overhead. (DEFAULT_RTC_INT_FREQ) - * For (3), we use interrupts at 64Hz or user specified periodic - * frequency, whichever is higher. - */ -#include <linux/mc146818rtc.h> -#include <linux/rtc.h> -#include <asm/rtc.h> - -#define DEFAULT_RTC_INT_FREQ 64 -#define DEFAULT_RTC_SHIFT 6 -#define RTC_NUM_INTS 1 - -static unsigned long hpet_rtc_flags; -static int hpet_prev_update_sec; -static struct rtc_time hpet_alarm_time; -static unsigned long hpet_pie_count; -static u32 hpet_t1_cmp; -static u32 hpet_default_delta; -static u32 hpet_pie_delta; -static unsigned long hpet_pie_limit; - -static rtc_irq_handler irq_handler; - -/* - * Check that the hpet counter c1 is ahead of the c2 - */ -static inline int hpet_cnt_ahead(u32 c1, u32 c2) -{ - return (s32)(c2 - c1) < 0; -} - -/* - * Registers a IRQ handler. - */ -int hpet_register_irq_handler(rtc_irq_handler handler) -{ - if (!is_hpet_enabled()) - return -ENODEV; - if (irq_handler) - return -EBUSY; - - irq_handler = handler; - - return 0; -} -EXPORT_SYMBOL_GPL(hpet_register_irq_handler); - -/* - * Deregisters the IRQ handler registered with hpet_register_irq_handler() - * and does cleanup. - */ -void hpet_unregister_irq_handler(rtc_irq_handler handler) -{ - if (!is_hpet_enabled()) - return; - - irq_handler = NULL; - hpet_rtc_flags = 0; -} -EXPORT_SYMBOL_GPL(hpet_unregister_irq_handler); - -/* - * Timer 1 for RTC emulation. We use one shot mode, as periodic mode - * is not supported by all HPET implementations for timer 1. - * - * hpet_rtc_timer_init() is called when the rtc is initialized. - */ -int hpet_rtc_timer_init(void) -{ - unsigned int cfg, cnt, delta; - unsigned long flags; - - if (!is_hpet_enabled()) - return 0; - - if (!hpet_default_delta) { - uint64_t clc; - - clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC; - clc >>= hpet_clockevent.shift + DEFAULT_RTC_SHIFT; - hpet_default_delta = clc; - } - - if (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit) - delta = hpet_default_delta; - else - delta = hpet_pie_delta; - - local_irq_save(flags); - - cnt = delta + hpet_readl(HPET_COUNTER); - hpet_writel(cnt, HPET_T1_CMP); - hpet_t1_cmp = cnt; - - cfg = hpet_readl(HPET_T1_CFG); - cfg &= ~HPET_TN_PERIODIC; - cfg |= HPET_TN_ENABLE | HPET_TN_32BIT; - hpet_writel(cfg, HPET_T1_CFG); - - local_irq_restore(flags); - - return 1; -} -EXPORT_SYMBOL_GPL(hpet_rtc_timer_init); - -static void hpet_disable_rtc_channel(void) -{ - unsigned long cfg; - cfg = hpet_readl(HPET_T1_CFG); - cfg &= ~HPET_TN_ENABLE; - hpet_writel(cfg, HPET_T1_CFG); -} - -/* - * The functions below are called from rtc driver. - * Return 0 if HPET is not being used. - * Otherwise do the necessary changes and return 1. - */ -int hpet_mask_rtc_irq_bit(unsigned long bit_mask) -{ - if (!is_hpet_enabled()) - return 0; - - hpet_rtc_flags &= ~bit_mask; - if (unlikely(!hpet_rtc_flags)) - hpet_disable_rtc_channel(); - - return 1; -} -EXPORT_SYMBOL_GPL(hpet_mask_rtc_irq_bit); - -int hpet_set_rtc_irq_bit(unsigned long bit_mask) -{ - unsigned long oldbits = hpet_rtc_flags; - - if (!is_hpet_enabled()) - return 0; - - hpet_rtc_flags |= bit_mask; - - if ((bit_mask & RTC_UIE) && !(oldbits & RTC_UIE)) - hpet_prev_update_sec = -1; - - if (!oldbits) - hpet_rtc_timer_init(); - - return 1; -} -EXPORT_SYMBOL_GPL(hpet_set_rtc_irq_bit); - -int hpet_set_alarm_time(unsigned char hrs, unsigned char min, - unsigned char sec) -{ - if (!is_hpet_enabled()) - return 0; - - hpet_alarm_time.tm_hour = hrs; - hpet_alarm_time.tm_min = min; - hpet_alarm_time.tm_sec = sec; - - return 1; -} -EXPORT_SYMBOL_GPL(hpet_set_alarm_time); - -int hpet_set_periodic_freq(unsigned long freq) -{ - uint64_t clc; - - if (!is_hpet_enabled()) - return 0; - - if (freq <= DEFAULT_RTC_INT_FREQ) - hpet_pie_limit = DEFAULT_RTC_INT_FREQ / freq; - else { - clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC; - do_div(clc, freq); - clc >>= hpet_clockevent.shift; - hpet_pie_delta = clc; - hpet_pie_limit = 0; - } - return 1; -} -EXPORT_SYMBOL_GPL(hpet_set_periodic_freq); - -int hpet_rtc_dropped_irq(void) -{ - return is_hpet_enabled(); -} -EXPORT_SYMBOL_GPL(hpet_rtc_dropped_irq); - -static void hpet_rtc_timer_reinit(void) -{ - unsigned int delta; - int lost_ints = -1; - - if (unlikely(!hpet_rtc_flags)) - hpet_disable_rtc_channel(); - - if (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit) - delta = hpet_default_delta; - else - delta = hpet_pie_delta; - - /* - * Increment the comparator value until we are ahead of the - * current count. - */ - do { - hpet_t1_cmp += delta; - hpet_writel(hpet_t1_cmp, HPET_T1_CMP); - lost_ints++; - } while (!hpet_cnt_ahead(hpet_t1_cmp, hpet_readl(HPET_COUNTER))); - - if (lost_ints) { - if (hpet_rtc_flags & RTC_PIE) - hpet_pie_count += lost_ints; - if (printk_ratelimit()) - printk(KERN_WARNING "hpet1: lost %d rtc interrupts\n", - lost_ints); - } -} - -irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id) -{ - struct rtc_time curr_time; - unsigned long rtc_int_flag = 0; - - hpet_rtc_timer_reinit(); - memset(&curr_time, 0, sizeof(struct rtc_time)); - - if (hpet_rtc_flags & (RTC_UIE | RTC_AIE)) - get_rtc_time(&curr_time); - - if (hpet_rtc_flags & RTC_UIE && - curr_time.tm_sec != hpet_prev_update_sec) { - if (hpet_prev_update_sec >= 0) - rtc_int_flag = RTC_UF; - hpet_prev_update_sec = curr_time.tm_sec; - } - - if (hpet_rtc_flags & RTC_PIE && - ++hpet_pie_count >= hpet_pie_limit) { - rtc_int_flag |= RTC_PF; - hpet_pie_count = 0; - } - - if (hpet_rtc_flags & RTC_AIE && - (curr_time.tm_sec == hpet_alarm_time.tm_sec) && - (curr_time.tm_min == hpet_alarm_time.tm_min) && - (curr_time.tm_hour == hpet_alarm_time.tm_hour)) - rtc_int_flag |= RTC_AF; - - if (rtc_int_flag) { - rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8)); - if (irq_handler) - irq_handler(rtc_int_flag, dev_id); - } - return IRQ_HANDLED; -} -EXPORT_SYMBOL_GPL(hpet_rtc_interrupt); -#endif |