1 // SPDX-License-Identifier: GPL-2.0-only
3 * linux/drivers/clocksource/arm_arch_timer.c
5 * Copyright (C) 2011 ARM Ltd.
9 #define pr_fmt(fmt) "arch_timer: " fmt
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/device.h>
14 #include <linux/smp.h>
15 #include <linux/cpu.h>
16 #include <linux/cpu_pm.h>
17 #include <linux/clockchips.h>
18 #include <linux/clocksource.h>
19 #include <linux/clocksource_ids.h>
20 #include <linux/interrupt.h>
21 #include <linux/kstrtox.h>
22 #include <linux/of_irq.h>
23 #include <linux/of_address.h>
25 #include <linux/slab.h>
26 #include <linux/sched/clock.h>
27 #include <linux/sched_clock.h>
28 #include <linux/acpi.h>
29 #include <linux/arm-smccc.h>
30 #include <linux/ptp_kvm.h>
32 #include <asm/arch_timer.h>
35 #include <clocksource/arm_arch_timer.h>
38 #define CNTTIDR_VIRT(n) (BIT(1) << ((n) * 4))
40 #define CNTACR(n) (0x40 + ((n) * 4))
41 #define CNTACR_RPCT BIT(0)
42 #define CNTACR_RVCT BIT(1)
43 #define CNTACR_RFRQ BIT(2)
44 #define CNTACR_RVOFF BIT(3)
45 #define CNTACR_RWVT BIT(4)
46 #define CNTACR_RWPT BIT(5)
48 #define CNTPCT_LO 0x00
49 #define CNTVCT_LO 0x08
51 #define CNTP_CVAL_LO 0x20
53 #define CNTV_CVAL_LO 0x30
57 * The minimum amount of time a generic counter is guaranteed to not roll over
60 #define MIN_ROLLOVER_SECS (40ULL * 365 * 24 * 3600)
62 static unsigned arch_timers_present __initdata;
66 struct clock_event_device evt;
69 static struct arch_timer *arch_timer_mem __ro_after_init;
71 #define to_arch_timer(e) container_of(e, struct arch_timer, evt)
73 static u32 arch_timer_rate __ro_after_init;
74 static int arch_timer_ppi[ARCH_TIMER_MAX_TIMER_PPI] __ro_after_init;
76 static const char *arch_timer_ppi_names[ARCH_TIMER_MAX_TIMER_PPI] = {
77 [ARCH_TIMER_PHYS_SECURE_PPI] = "sec-phys",
78 [ARCH_TIMER_PHYS_NONSECURE_PPI] = "phys",
79 [ARCH_TIMER_VIRT_PPI] = "virt",
80 [ARCH_TIMER_HYP_PPI] = "hyp-phys",
81 [ARCH_TIMER_HYP_VIRT_PPI] = "hyp-virt",
84 static struct clock_event_device __percpu *arch_timer_evt;
86 static enum arch_timer_ppi_nr arch_timer_uses_ppi __ro_after_init = ARCH_TIMER_VIRT_PPI;
87 static bool arch_timer_c3stop __ro_after_init;
88 static bool arch_timer_mem_use_virtual __ro_after_init;
89 static bool arch_counter_suspend_stop __ro_after_init;
90 #ifdef CONFIG_GENERIC_GETTIMEOFDAY
91 static enum vdso_clock_mode vdso_default = VDSO_CLOCKMODE_ARCHTIMER;
93 static enum vdso_clock_mode vdso_default = VDSO_CLOCKMODE_NONE;
94 #endif /* CONFIG_GENERIC_GETTIMEOFDAY */
96 static cpumask_t evtstrm_available = CPU_MASK_NONE;
97 static bool evtstrm_enable __ro_after_init = IS_ENABLED(CONFIG_ARM_ARCH_TIMER_EVTSTREAM);
99 static int __init early_evtstrm_cfg(char *buf)
101 return kstrtobool(buf, &evtstrm_enable);
103 early_param("clocksource.arm_arch_timer.evtstrm", early_evtstrm_cfg);
106 * Makes an educated guess at a valid counter width based on the Generic Timer
107 * specification. Of note:
108 * 1) the system counter is at least 56 bits wide
109 * 2) a roll-over time of not less than 40 years
111 * See 'ARM DDI 0487G.a D11.1.2 ("The system counter")' for more details.
113 static int arch_counter_get_width(void)
115 u64 min_cycles = MIN_ROLLOVER_SECS * arch_timer_rate;
117 /* guarantee the returned width is within the valid range */
118 return clamp_val(ilog2(min_cycles - 1) + 1, 56, 64);
122 * Architected system timer support.
125 static __always_inline
126 void arch_timer_reg_write(int access, enum arch_timer_reg reg, u64 val,
127 struct clock_event_device *clk)
129 if (access == ARCH_TIMER_MEM_PHYS_ACCESS) {
130 struct arch_timer *timer = to_arch_timer(clk);
132 case ARCH_TIMER_REG_CTRL:
133 writel_relaxed((u32)val, timer->base + CNTP_CTL);
135 case ARCH_TIMER_REG_CVAL:
137 * Not guaranteed to be atomic, so the timer
138 * must be disabled at this point.
140 writeq_relaxed(val, timer->base + CNTP_CVAL_LO);
145 } else if (access == ARCH_TIMER_MEM_VIRT_ACCESS) {
146 struct arch_timer *timer = to_arch_timer(clk);
148 case ARCH_TIMER_REG_CTRL:
149 writel_relaxed((u32)val, timer->base + CNTV_CTL);
151 case ARCH_TIMER_REG_CVAL:
152 /* Same restriction as above */
153 writeq_relaxed(val, timer->base + CNTV_CVAL_LO);
159 arch_timer_reg_write_cp15(access, reg, val);
163 static __always_inline
164 u32 arch_timer_reg_read(int access, enum arch_timer_reg reg,
165 struct clock_event_device *clk)
169 if (access == ARCH_TIMER_MEM_PHYS_ACCESS) {
170 struct arch_timer *timer = to_arch_timer(clk);
172 case ARCH_TIMER_REG_CTRL:
173 val = readl_relaxed(timer->base + CNTP_CTL);
178 } else if (access == ARCH_TIMER_MEM_VIRT_ACCESS) {
179 struct arch_timer *timer = to_arch_timer(clk);
181 case ARCH_TIMER_REG_CTRL:
182 val = readl_relaxed(timer->base + CNTV_CTL);
188 val = arch_timer_reg_read_cp15(access, reg);
194 static noinstr u64 raw_counter_get_cntpct_stable(void)
196 return __arch_counter_get_cntpct_stable();
199 static notrace u64 arch_counter_get_cntpct_stable(void)
202 preempt_disable_notrace();
203 val = __arch_counter_get_cntpct_stable();
204 preempt_enable_notrace();
208 static noinstr u64 arch_counter_get_cntpct(void)
210 return __arch_counter_get_cntpct();
213 static noinstr u64 raw_counter_get_cntvct_stable(void)
215 return __arch_counter_get_cntvct_stable();
218 static notrace u64 arch_counter_get_cntvct_stable(void)
221 preempt_disable_notrace();
222 val = __arch_counter_get_cntvct_stable();
223 preempt_enable_notrace();
227 static noinstr u64 arch_counter_get_cntvct(void)
229 return __arch_counter_get_cntvct();
233 * Default to cp15 based access because arm64 uses this function for
234 * sched_clock() before DT is probed and the cp15 method is guaranteed
235 * to exist on arm64. arm doesn't use this before DT is probed so even
236 * if we don't have the cp15 accessors we won't have a problem.
238 u64 (*arch_timer_read_counter)(void) __ro_after_init = arch_counter_get_cntvct;
239 EXPORT_SYMBOL_GPL(arch_timer_read_counter);
241 static u64 arch_counter_read(struct clocksource *cs)
243 return arch_timer_read_counter();
246 static u64 arch_counter_read_cc(const struct cyclecounter *cc)
248 return arch_timer_read_counter();
251 static struct clocksource clocksource_counter = {
252 .name = "arch_sys_counter",
253 .id = CSID_ARM_ARCH_COUNTER,
255 .read = arch_counter_read,
256 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
259 static struct cyclecounter cyclecounter __ro_after_init = {
260 .read = arch_counter_read_cc,
263 struct ate_acpi_oem_info {
264 char oem_id[ACPI_OEM_ID_SIZE + 1];
265 char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1];
269 #ifdef CONFIG_FSL_ERRATUM_A008585
271 * The number of retries is an arbitrary value well beyond the highest number
272 * of iterations the loop has been observed to take.
274 #define __fsl_a008585_read_reg(reg) ({ \
276 int _retries = 200; \
279 _old = read_sysreg(reg); \
280 _new = read_sysreg(reg); \
282 } while (unlikely(_old != _new) && _retries); \
284 WARN_ON_ONCE(!_retries); \
288 static u64 notrace fsl_a008585_read_cntpct_el0(void)
290 return __fsl_a008585_read_reg(cntpct_el0);
293 static u64 notrace fsl_a008585_read_cntvct_el0(void)
295 return __fsl_a008585_read_reg(cntvct_el0);
299 #ifdef CONFIG_HISILICON_ERRATUM_161010101
301 * Verify whether the value of the second read is larger than the first by
302 * less than 32 is the only way to confirm the value is correct, so clear the
303 * lower 5 bits to check whether the difference is greater than 32 or not.
304 * Theoretically the erratum should not occur more than twice in succession
305 * when reading the system counter, but it is possible that some interrupts
306 * may lead to more than twice read errors, triggering the warning, so setting
307 * the number of retries far beyond the number of iterations the loop has been
310 #define __hisi_161010101_read_reg(reg) ({ \
315 _old = read_sysreg(reg); \
316 _new = read_sysreg(reg); \
318 } while (unlikely((_new - _old) >> 5) && _retries); \
320 WARN_ON_ONCE(!_retries); \
324 static u64 notrace hisi_161010101_read_cntpct_el0(void)
326 return __hisi_161010101_read_reg(cntpct_el0);
329 static u64 notrace hisi_161010101_read_cntvct_el0(void)
331 return __hisi_161010101_read_reg(cntvct_el0);
334 static const struct ate_acpi_oem_info hisi_161010101_oem_info[] = {
336 * Note that trailing spaces are required to properly match
337 * the OEM table information.
341 .oem_table_id = "HIP05 ",
346 .oem_table_id = "HIP06 ",
351 .oem_table_id = "HIP07 ",
354 { /* Sentinel indicating the end of the OEM array */ },
358 #ifdef CONFIG_ARM64_ERRATUM_858921
359 static u64 notrace arm64_858921_read_cntpct_el0(void)
363 old = read_sysreg(cntpct_el0);
364 new = read_sysreg(cntpct_el0);
365 return (((old ^ new) >> 32) & 1) ? old : new;
368 static u64 notrace arm64_858921_read_cntvct_el0(void)
372 old = read_sysreg(cntvct_el0);
373 new = read_sysreg(cntvct_el0);
374 return (((old ^ new) >> 32) & 1) ? old : new;
378 #ifdef CONFIG_SUN50I_ERRATUM_UNKNOWN1
380 * The low bits of the counter registers are indeterminate while bit 10 or
381 * greater is rolling over. Since the counter value can jump both backward
382 * (7ff -> 000 -> 800) and forward (7ff -> fff -> 800), ignore register values
383 * with all ones or all zeros in the low bits. Bound the loop by the maximum
384 * number of CPU cycles in 3 consecutive 24 MHz counter periods.
386 #define __sun50i_a64_read_reg(reg) ({ \
388 int _retries = 150; \
391 _val = read_sysreg(reg); \
393 } while (((_val + 1) & GENMASK(8, 0)) <= 1 && _retries); \
395 WARN_ON_ONCE(!_retries); \
399 static u64 notrace sun50i_a64_read_cntpct_el0(void)
401 return __sun50i_a64_read_reg(cntpct_el0);
404 static u64 notrace sun50i_a64_read_cntvct_el0(void)
406 return __sun50i_a64_read_reg(cntvct_el0);
410 #ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
411 DEFINE_PER_CPU(const struct arch_timer_erratum_workaround *, timer_unstable_counter_workaround);
412 EXPORT_SYMBOL_GPL(timer_unstable_counter_workaround);
414 static atomic_t timer_unstable_counter_workaround_in_use = ATOMIC_INIT(0);
417 * Force the inlining of this function so that the register accesses
418 * can be themselves correctly inlined.
420 static __always_inline
421 void erratum_set_next_event_generic(const int access, unsigned long evt,
422 struct clock_event_device *clk)
427 ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, clk);
428 ctrl |= ARCH_TIMER_CTRL_ENABLE;
429 ctrl &= ~ARCH_TIMER_CTRL_IT_MASK;
431 if (access == ARCH_TIMER_PHYS_ACCESS) {
432 cval = evt + arch_counter_get_cntpct_stable();
433 write_sysreg(cval, cntp_cval_el0);
435 cval = evt + arch_counter_get_cntvct_stable();
436 write_sysreg(cval, cntv_cval_el0);
439 arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
442 static __maybe_unused int erratum_set_next_event_virt(unsigned long evt,
443 struct clock_event_device *clk)
445 erratum_set_next_event_generic(ARCH_TIMER_VIRT_ACCESS, evt, clk);
449 static __maybe_unused int erratum_set_next_event_phys(unsigned long evt,
450 struct clock_event_device *clk)
452 erratum_set_next_event_generic(ARCH_TIMER_PHYS_ACCESS, evt, clk);
456 static const struct arch_timer_erratum_workaround ool_workarounds[] = {
457 #ifdef CONFIG_FSL_ERRATUM_A008585
459 .match_type = ate_match_dt,
460 .id = "fsl,erratum-a008585",
461 .desc = "Freescale erratum a005858",
462 .read_cntpct_el0 = fsl_a008585_read_cntpct_el0,
463 .read_cntvct_el0 = fsl_a008585_read_cntvct_el0,
464 .set_next_event_phys = erratum_set_next_event_phys,
465 .set_next_event_virt = erratum_set_next_event_virt,
468 #ifdef CONFIG_HISILICON_ERRATUM_161010101
470 .match_type = ate_match_dt,
471 .id = "hisilicon,erratum-161010101",
472 .desc = "HiSilicon erratum 161010101",
473 .read_cntpct_el0 = hisi_161010101_read_cntpct_el0,
474 .read_cntvct_el0 = hisi_161010101_read_cntvct_el0,
475 .set_next_event_phys = erratum_set_next_event_phys,
476 .set_next_event_virt = erratum_set_next_event_virt,
479 .match_type = ate_match_acpi_oem_info,
480 .id = hisi_161010101_oem_info,
481 .desc = "HiSilicon erratum 161010101",
482 .read_cntpct_el0 = hisi_161010101_read_cntpct_el0,
483 .read_cntvct_el0 = hisi_161010101_read_cntvct_el0,
484 .set_next_event_phys = erratum_set_next_event_phys,
485 .set_next_event_virt = erratum_set_next_event_virt,
488 #ifdef CONFIG_ARM64_ERRATUM_858921
490 .match_type = ate_match_local_cap_id,
491 .id = (void *)ARM64_WORKAROUND_858921,
492 .desc = "ARM erratum 858921",
493 .read_cntpct_el0 = arm64_858921_read_cntpct_el0,
494 .read_cntvct_el0 = arm64_858921_read_cntvct_el0,
495 .set_next_event_phys = erratum_set_next_event_phys,
496 .set_next_event_virt = erratum_set_next_event_virt,
499 #ifdef CONFIG_SUN50I_ERRATUM_UNKNOWN1
501 .match_type = ate_match_dt,
502 .id = "allwinner,erratum-unknown1",
503 .desc = "Allwinner erratum UNKNOWN1",
504 .read_cntpct_el0 = sun50i_a64_read_cntpct_el0,
505 .read_cntvct_el0 = sun50i_a64_read_cntvct_el0,
506 .set_next_event_phys = erratum_set_next_event_phys,
507 .set_next_event_virt = erratum_set_next_event_virt,
510 #ifdef CONFIG_ARM64_ERRATUM_1418040
512 .match_type = ate_match_local_cap_id,
513 .id = (void *)ARM64_WORKAROUND_1418040,
514 .desc = "ARM erratum 1418040",
515 .disable_compat_vdso = true,
520 typedef bool (*ate_match_fn_t)(const struct arch_timer_erratum_workaround *,
524 bool arch_timer_check_dt_erratum(const struct arch_timer_erratum_workaround *wa,
527 const struct device_node *np = arg;
529 return of_property_read_bool(np, wa->id);
533 bool arch_timer_check_local_cap_erratum(const struct arch_timer_erratum_workaround *wa,
536 return this_cpu_has_cap((uintptr_t)wa->id);
541 bool arch_timer_check_acpi_oem_erratum(const struct arch_timer_erratum_workaround *wa,
544 static const struct ate_acpi_oem_info empty_oem_info = {};
545 const struct ate_acpi_oem_info *info = wa->id;
546 const struct acpi_table_header *table = arg;
548 /* Iterate over the ACPI OEM info array, looking for a match */
549 while (memcmp(info, &empty_oem_info, sizeof(*info))) {
550 if (!memcmp(info->oem_id, table->oem_id, ACPI_OEM_ID_SIZE) &&
551 !memcmp(info->oem_table_id, table->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) &&
552 info->oem_revision == table->oem_revision)
561 static const struct arch_timer_erratum_workaround *
562 arch_timer_iterate_errata(enum arch_timer_erratum_match_type type,
563 ate_match_fn_t match_fn,
568 for (i = 0; i < ARRAY_SIZE(ool_workarounds); i++) {
569 if (ool_workarounds[i].match_type != type)
572 if (match_fn(&ool_workarounds[i], arg))
573 return &ool_workarounds[i];
580 void arch_timer_enable_workaround(const struct arch_timer_erratum_workaround *wa,
586 __this_cpu_write(timer_unstable_counter_workaround, wa);
588 for_each_possible_cpu(i)
589 per_cpu(timer_unstable_counter_workaround, i) = wa;
592 if (wa->read_cntvct_el0 || wa->read_cntpct_el0)
593 atomic_set(&timer_unstable_counter_workaround_in_use, 1);
596 * Don't use the vdso fastpath if errata require using the
597 * out-of-line counter accessor. We may change our mind pretty
598 * late in the game (with a per-CPU erratum, for example), so
599 * change both the default value and the vdso itself.
601 if (wa->read_cntvct_el0) {
602 clocksource_counter.vdso_clock_mode = VDSO_CLOCKMODE_NONE;
603 vdso_default = VDSO_CLOCKMODE_NONE;
604 } else if (wa->disable_compat_vdso && vdso_default != VDSO_CLOCKMODE_NONE) {
605 vdso_default = VDSO_CLOCKMODE_ARCHTIMER_NOCOMPAT;
606 clocksource_counter.vdso_clock_mode = vdso_default;
610 static void arch_timer_check_ool_workaround(enum arch_timer_erratum_match_type type,
613 const struct arch_timer_erratum_workaround *wa, *__wa;
614 ate_match_fn_t match_fn = NULL;
619 match_fn = arch_timer_check_dt_erratum;
621 case ate_match_local_cap_id:
622 match_fn = arch_timer_check_local_cap_erratum;
625 case ate_match_acpi_oem_info:
626 match_fn = arch_timer_check_acpi_oem_erratum;
633 wa = arch_timer_iterate_errata(type, match_fn, arg);
637 __wa = __this_cpu_read(timer_unstable_counter_workaround);
638 if (__wa && wa != __wa)
639 pr_warn("Can't enable workaround for %s (clashes with %s\n)",
640 wa->desc, __wa->desc);
645 arch_timer_enable_workaround(wa, local);
646 pr_info("Enabling %s workaround for %s\n",
647 local ? "local" : "global", wa->desc);
650 static bool arch_timer_this_cpu_has_cntvct_wa(void)
652 return has_erratum_handler(read_cntvct_el0);
655 static bool arch_timer_counter_has_wa(void)
657 return atomic_read(&timer_unstable_counter_workaround_in_use);
660 #define arch_timer_check_ool_workaround(t,a) do { } while(0)
661 #define arch_timer_this_cpu_has_cntvct_wa() ({false;})
662 #define arch_timer_counter_has_wa() ({false;})
663 #endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */
665 static __always_inline irqreturn_t timer_handler(const int access,
666 struct clock_event_device *evt)
670 ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, evt);
671 if (ctrl & ARCH_TIMER_CTRL_IT_STAT) {
672 ctrl |= ARCH_TIMER_CTRL_IT_MASK;
673 arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, evt);
674 evt->event_handler(evt);
681 static irqreturn_t arch_timer_handler_virt(int irq, void *dev_id)
683 struct clock_event_device *evt = dev_id;
685 return timer_handler(ARCH_TIMER_VIRT_ACCESS, evt);
688 static irqreturn_t arch_timer_handler_phys(int irq, void *dev_id)
690 struct clock_event_device *evt = dev_id;
692 return timer_handler(ARCH_TIMER_PHYS_ACCESS, evt);
695 static irqreturn_t arch_timer_handler_phys_mem(int irq, void *dev_id)
697 struct clock_event_device *evt = dev_id;
699 return timer_handler(ARCH_TIMER_MEM_PHYS_ACCESS, evt);
702 static irqreturn_t arch_timer_handler_virt_mem(int irq, void *dev_id)
704 struct clock_event_device *evt = dev_id;
706 return timer_handler(ARCH_TIMER_MEM_VIRT_ACCESS, evt);
709 static __always_inline int arch_timer_shutdown(const int access,
710 struct clock_event_device *clk)
714 ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, clk);
715 ctrl &= ~ARCH_TIMER_CTRL_ENABLE;
716 arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
721 static int arch_timer_shutdown_virt(struct clock_event_device *clk)
723 return arch_timer_shutdown(ARCH_TIMER_VIRT_ACCESS, clk);
726 static int arch_timer_shutdown_phys(struct clock_event_device *clk)
728 return arch_timer_shutdown(ARCH_TIMER_PHYS_ACCESS, clk);
731 static int arch_timer_shutdown_virt_mem(struct clock_event_device *clk)
733 return arch_timer_shutdown(ARCH_TIMER_MEM_VIRT_ACCESS, clk);
736 static int arch_timer_shutdown_phys_mem(struct clock_event_device *clk)
738 return arch_timer_shutdown(ARCH_TIMER_MEM_PHYS_ACCESS, clk);
741 static __always_inline void set_next_event(const int access, unsigned long evt,
742 struct clock_event_device *clk)
747 ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, clk);
748 ctrl |= ARCH_TIMER_CTRL_ENABLE;
749 ctrl &= ~ARCH_TIMER_CTRL_IT_MASK;
751 if (access == ARCH_TIMER_PHYS_ACCESS)
752 cnt = __arch_counter_get_cntpct();
754 cnt = __arch_counter_get_cntvct();
756 arch_timer_reg_write(access, ARCH_TIMER_REG_CVAL, evt + cnt, clk);
757 arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
760 static int arch_timer_set_next_event_virt(unsigned long evt,
761 struct clock_event_device *clk)
763 set_next_event(ARCH_TIMER_VIRT_ACCESS, evt, clk);
767 static int arch_timer_set_next_event_phys(unsigned long evt,
768 struct clock_event_device *clk)
770 set_next_event(ARCH_TIMER_PHYS_ACCESS, evt, clk);
774 static noinstr u64 arch_counter_get_cnt_mem(struct arch_timer *t, int offset_lo)
776 u32 cnt_lo, cnt_hi, tmp_hi;
779 cnt_hi = __le32_to_cpu((__le32 __force)__raw_readl(t->base + offset_lo + 4));
780 cnt_lo = __le32_to_cpu((__le32 __force)__raw_readl(t->base + offset_lo));
781 tmp_hi = __le32_to_cpu((__le32 __force)__raw_readl(t->base + offset_lo + 4));
782 } while (cnt_hi != tmp_hi);
784 return ((u64) cnt_hi << 32) | cnt_lo;
787 static __always_inline void set_next_event_mem(const int access, unsigned long evt,
788 struct clock_event_device *clk)
790 struct arch_timer *timer = to_arch_timer(clk);
794 ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, clk);
796 /* Timer must be disabled before programming CVAL */
797 if (ctrl & ARCH_TIMER_CTRL_ENABLE) {
798 ctrl &= ~ARCH_TIMER_CTRL_ENABLE;
799 arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
802 ctrl |= ARCH_TIMER_CTRL_ENABLE;
803 ctrl &= ~ARCH_TIMER_CTRL_IT_MASK;
805 if (access == ARCH_TIMER_MEM_VIRT_ACCESS)
806 cnt = arch_counter_get_cnt_mem(timer, CNTVCT_LO);
808 cnt = arch_counter_get_cnt_mem(timer, CNTPCT_LO);
810 arch_timer_reg_write(access, ARCH_TIMER_REG_CVAL, evt + cnt, clk);
811 arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
814 static int arch_timer_set_next_event_virt_mem(unsigned long evt,
815 struct clock_event_device *clk)
817 set_next_event_mem(ARCH_TIMER_MEM_VIRT_ACCESS, evt, clk);
821 static int arch_timer_set_next_event_phys_mem(unsigned long evt,
822 struct clock_event_device *clk)
824 set_next_event_mem(ARCH_TIMER_MEM_PHYS_ACCESS, evt, clk);
828 static u64 __arch_timer_check_delta(void)
831 const struct midr_range broken_cval_midrs[] = {
833 * XGene-1 implements CVAL in terms of TVAL, meaning
834 * that the maximum timer range is 32bit. Shame on them.
836 * Note that TVAL is signed, thus has only 31 of its
837 * 32 bits to express magnitude.
839 MIDR_REV_RANGE(MIDR_CPU_MODEL(ARM_CPU_IMP_APM,
841 APM_CPU_VAR_POTENZA, 0x0, 0xf),
845 if (is_midr_in_range_list(read_cpuid_id(), broken_cval_midrs)) {
846 pr_warn_once("Broken CNTx_CVAL_EL1, using 31 bit TVAL instead.\n");
847 return CLOCKSOURCE_MASK(31);
850 return CLOCKSOURCE_MASK(arch_counter_get_width());
853 static void __arch_timer_setup(unsigned type,
854 struct clock_event_device *clk)
858 clk->features = CLOCK_EVT_FEAT_ONESHOT;
860 if (type == ARCH_TIMER_TYPE_CP15) {
861 typeof(clk->set_next_event) sne;
863 arch_timer_check_ool_workaround(ate_match_local_cap_id, NULL);
865 if (arch_timer_c3stop)
866 clk->features |= CLOCK_EVT_FEAT_C3STOP;
867 clk->name = "arch_sys_timer";
869 clk->cpumask = cpumask_of(smp_processor_id());
870 clk->irq = arch_timer_ppi[arch_timer_uses_ppi];
871 switch (arch_timer_uses_ppi) {
872 case ARCH_TIMER_VIRT_PPI:
873 clk->set_state_shutdown = arch_timer_shutdown_virt;
874 clk->set_state_oneshot_stopped = arch_timer_shutdown_virt;
875 sne = erratum_handler(set_next_event_virt);
877 case ARCH_TIMER_PHYS_SECURE_PPI:
878 case ARCH_TIMER_PHYS_NONSECURE_PPI:
879 case ARCH_TIMER_HYP_PPI:
880 clk->set_state_shutdown = arch_timer_shutdown_phys;
881 clk->set_state_oneshot_stopped = arch_timer_shutdown_phys;
882 sne = erratum_handler(set_next_event_phys);
888 clk->set_next_event = sne;
889 max_delta = __arch_timer_check_delta();
891 clk->features |= CLOCK_EVT_FEAT_DYNIRQ;
892 clk->name = "arch_mem_timer";
894 clk->cpumask = cpu_possible_mask;
895 if (arch_timer_mem_use_virtual) {
896 clk->set_state_shutdown = arch_timer_shutdown_virt_mem;
897 clk->set_state_oneshot_stopped = arch_timer_shutdown_virt_mem;
898 clk->set_next_event =
899 arch_timer_set_next_event_virt_mem;
901 clk->set_state_shutdown = arch_timer_shutdown_phys_mem;
902 clk->set_state_oneshot_stopped = arch_timer_shutdown_phys_mem;
903 clk->set_next_event =
904 arch_timer_set_next_event_phys_mem;
907 max_delta = CLOCKSOURCE_MASK(56);
910 clk->set_state_shutdown(clk);
912 clockevents_config_and_register(clk, arch_timer_rate, 0xf, max_delta);
915 static void arch_timer_evtstrm_enable(unsigned int divider)
917 u32 cntkctl = arch_timer_get_cntkctl();
920 /* ECV is likely to require a large divider. Use the EVNTIS flag. */
921 if (cpus_have_final_cap(ARM64_HAS_ECV) && divider > 15) {
922 cntkctl |= ARCH_TIMER_EVT_INTERVAL_SCALE;
927 divider = min(divider, 15U);
928 cntkctl &= ~ARCH_TIMER_EVT_TRIGGER_MASK;
929 /* Set the divider and enable virtual event stream */
930 cntkctl |= (divider << ARCH_TIMER_EVT_TRIGGER_SHIFT)
931 | ARCH_TIMER_VIRT_EVT_EN;
932 arch_timer_set_cntkctl(cntkctl);
933 arch_timer_set_evtstrm_feature();
934 cpumask_set_cpu(smp_processor_id(), &evtstrm_available);
937 static void arch_timer_configure_evtstream(void)
939 int evt_stream_div, lsb;
942 * As the event stream can at most be generated at half the frequency
943 * of the counter, use half the frequency when computing the divider.
945 evt_stream_div = arch_timer_rate / ARCH_TIMER_EVT_STREAM_FREQ / 2;
948 * Find the closest power of two to the divisor. If the adjacent bit
949 * of lsb (last set bit, starts from 0) is set, then we use (lsb + 1).
951 lsb = fls(evt_stream_div) - 1;
952 if (lsb > 0 && (evt_stream_div & BIT(lsb - 1)))
955 /* enable event stream */
956 arch_timer_evtstrm_enable(max(0, lsb));
959 static int arch_timer_evtstrm_starting_cpu(unsigned int cpu)
961 arch_timer_configure_evtstream();
965 static int arch_timer_evtstrm_dying_cpu(unsigned int cpu)
967 cpumask_clear_cpu(smp_processor_id(), &evtstrm_available);
971 static int __init arch_timer_evtstrm_register(void)
973 if (!arch_timer_evt || !evtstrm_enable)
976 return cpuhp_setup_state(CPUHP_AP_ARM_ARCH_TIMER_EVTSTRM_STARTING,
977 "clockevents/arm/arch_timer_evtstrm:starting",
978 arch_timer_evtstrm_starting_cpu,
979 arch_timer_evtstrm_dying_cpu);
981 core_initcall(arch_timer_evtstrm_register);
983 static void arch_counter_set_user_access(void)
985 u32 cntkctl = arch_timer_get_cntkctl();
987 /* Disable user access to the timers and both counters */
988 /* Also disable virtual event stream */
989 cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN
990 | ARCH_TIMER_USR_VT_ACCESS_EN
991 | ARCH_TIMER_USR_VCT_ACCESS_EN
992 | ARCH_TIMER_VIRT_EVT_EN
993 | ARCH_TIMER_USR_PCT_ACCESS_EN);
996 * Enable user access to the virtual counter if it doesn't
997 * need to be workaround. The vdso may have been already
1000 if (arch_timer_this_cpu_has_cntvct_wa())
1001 pr_info("CPU%d: Trapping CNTVCT access\n", smp_processor_id());
1003 cntkctl |= ARCH_TIMER_USR_VCT_ACCESS_EN;
1005 arch_timer_set_cntkctl(cntkctl);
1008 static bool arch_timer_has_nonsecure_ppi(void)
1010 return (arch_timer_uses_ppi == ARCH_TIMER_PHYS_SECURE_PPI &&
1011 arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]);
1014 static u32 check_ppi_trigger(int irq)
1016 u32 flags = irq_get_trigger_type(irq);
1018 if (flags != IRQF_TRIGGER_HIGH && flags != IRQF_TRIGGER_LOW) {
1019 pr_warn("WARNING: Invalid trigger for IRQ%d, assuming level low\n", irq);
1020 pr_warn("WARNING: Please fix your firmware\n");
1021 flags = IRQF_TRIGGER_LOW;
1027 static int arch_timer_starting_cpu(unsigned int cpu)
1029 struct clock_event_device *clk = this_cpu_ptr(arch_timer_evt);
1032 __arch_timer_setup(ARCH_TIMER_TYPE_CP15, clk);
1034 flags = check_ppi_trigger(arch_timer_ppi[arch_timer_uses_ppi]);
1035 enable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], flags);
1037 if (arch_timer_has_nonsecure_ppi()) {
1038 flags = check_ppi_trigger(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]);
1039 enable_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI],
1043 arch_counter_set_user_access();
1048 static int validate_timer_rate(void)
1050 if (!arch_timer_rate)
1053 /* Arch timer frequency < 1MHz can cause trouble */
1054 WARN_ON(arch_timer_rate < 1000000);
1060 * For historical reasons, when probing with DT we use whichever (non-zero)
1061 * rate was probed first, and don't verify that others match. If the first node
1062 * probed has a clock-frequency property, this overrides the HW register.
1064 static void __init arch_timer_of_configure_rate(u32 rate, struct device_node *np)
1066 /* Who has more than one independent system counter? */
1067 if (arch_timer_rate)
1070 if (of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
1071 arch_timer_rate = rate;
1073 /* Check the timer frequency. */
1074 if (validate_timer_rate())
1075 pr_warn("frequency not available\n");
1078 static void __init arch_timer_banner(unsigned type)
1080 pr_info("%s%s%s timer(s) running at %lu.%02luMHz (%s%s%s).\n",
1081 type & ARCH_TIMER_TYPE_CP15 ? "cp15" : "",
1082 type == (ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM) ?
1084 type & ARCH_TIMER_TYPE_MEM ? "mmio" : "",
1085 (unsigned long)arch_timer_rate / 1000000,
1086 (unsigned long)(arch_timer_rate / 10000) % 100,
1087 type & ARCH_TIMER_TYPE_CP15 ?
1088 (arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI) ? "virt" : "phys" :
1090 type == (ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM) ? "/" : "",
1091 type & ARCH_TIMER_TYPE_MEM ?
1092 arch_timer_mem_use_virtual ? "virt" : "phys" :
1096 u32 arch_timer_get_rate(void)
1098 return arch_timer_rate;
1101 bool arch_timer_evtstrm_available(void)
1104 * We might get called from a preemptible context. This is fine
1105 * because availability of the event stream should be always the same
1106 * for a preemptible context and context where we might resume a task.
1108 return cpumask_test_cpu(raw_smp_processor_id(), &evtstrm_available);
1111 static noinstr u64 arch_counter_get_cntvct_mem(void)
1113 return arch_counter_get_cnt_mem(arch_timer_mem, CNTVCT_LO);
1116 static struct arch_timer_kvm_info arch_timer_kvm_info;
1118 struct arch_timer_kvm_info *arch_timer_get_kvm_info(void)
1120 return &arch_timer_kvm_info;
1123 static void __init arch_counter_register(unsigned type)
1129 /* Register the CP15 based counter if we have one */
1130 if (type & ARCH_TIMER_TYPE_CP15) {
1133 if ((IS_ENABLED(CONFIG_ARM64) && !is_hyp_mode_available()) ||
1134 arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI) {
1135 if (arch_timer_counter_has_wa()) {
1136 rd = arch_counter_get_cntvct_stable;
1137 scr = raw_counter_get_cntvct_stable;
1139 rd = arch_counter_get_cntvct;
1140 scr = arch_counter_get_cntvct;
1143 if (arch_timer_counter_has_wa()) {
1144 rd = arch_counter_get_cntpct_stable;
1145 scr = raw_counter_get_cntpct_stable;
1147 rd = arch_counter_get_cntpct;
1148 scr = arch_counter_get_cntpct;
1152 arch_timer_read_counter = rd;
1153 clocksource_counter.vdso_clock_mode = vdso_default;
1155 arch_timer_read_counter = arch_counter_get_cntvct_mem;
1156 scr = arch_counter_get_cntvct_mem;
1159 width = arch_counter_get_width();
1160 clocksource_counter.mask = CLOCKSOURCE_MASK(width);
1161 cyclecounter.mask = CLOCKSOURCE_MASK(width);
1163 if (!arch_counter_suspend_stop)
1164 clocksource_counter.flags |= CLOCK_SOURCE_SUSPEND_NONSTOP;
1165 start_count = arch_timer_read_counter();
1166 clocksource_register_hz(&clocksource_counter, arch_timer_rate);
1167 cyclecounter.mult = clocksource_counter.mult;
1168 cyclecounter.shift = clocksource_counter.shift;
1169 timecounter_init(&arch_timer_kvm_info.timecounter,
1170 &cyclecounter, start_count);
1172 sched_clock_register(scr, width, arch_timer_rate);
1175 static void arch_timer_stop(struct clock_event_device *clk)
1177 pr_debug("disable IRQ%d cpu #%d\n", clk->irq, smp_processor_id());
1179 disable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi]);
1180 if (arch_timer_has_nonsecure_ppi())
1181 disable_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]);
1183 clk->set_state_shutdown(clk);
1186 static int arch_timer_dying_cpu(unsigned int cpu)
1188 struct clock_event_device *clk = this_cpu_ptr(arch_timer_evt);
1190 arch_timer_stop(clk);
1194 #ifdef CONFIG_CPU_PM
1195 static DEFINE_PER_CPU(unsigned long, saved_cntkctl);
1196 static int arch_timer_cpu_pm_notify(struct notifier_block *self,
1197 unsigned long action, void *hcpu)
1199 if (action == CPU_PM_ENTER) {
1200 __this_cpu_write(saved_cntkctl, arch_timer_get_cntkctl());
1202 cpumask_clear_cpu(smp_processor_id(), &evtstrm_available);
1203 } else if (action == CPU_PM_ENTER_FAILED || action == CPU_PM_EXIT) {
1204 arch_timer_set_cntkctl(__this_cpu_read(saved_cntkctl));
1206 if (arch_timer_have_evtstrm_feature())
1207 cpumask_set_cpu(smp_processor_id(), &evtstrm_available);
1212 static struct notifier_block arch_timer_cpu_pm_notifier = {
1213 .notifier_call = arch_timer_cpu_pm_notify,
1216 static int __init arch_timer_cpu_pm_init(void)
1218 return cpu_pm_register_notifier(&arch_timer_cpu_pm_notifier);
1221 static void __init arch_timer_cpu_pm_deinit(void)
1223 WARN_ON(cpu_pm_unregister_notifier(&arch_timer_cpu_pm_notifier));
1227 static int __init arch_timer_cpu_pm_init(void)
1232 static void __init arch_timer_cpu_pm_deinit(void)
1237 static int __init arch_timer_register(void)
1242 arch_timer_evt = alloc_percpu(struct clock_event_device);
1243 if (!arch_timer_evt) {
1248 ppi = arch_timer_ppi[arch_timer_uses_ppi];
1249 switch (arch_timer_uses_ppi) {
1250 case ARCH_TIMER_VIRT_PPI:
1251 err = request_percpu_irq(ppi, arch_timer_handler_virt,
1252 "arch_timer", arch_timer_evt);
1254 case ARCH_TIMER_PHYS_SECURE_PPI:
1255 case ARCH_TIMER_PHYS_NONSECURE_PPI:
1256 err = request_percpu_irq(ppi, arch_timer_handler_phys,
1257 "arch_timer", arch_timer_evt);
1258 if (!err && arch_timer_has_nonsecure_ppi()) {
1259 ppi = arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI];
1260 err = request_percpu_irq(ppi, arch_timer_handler_phys,
1261 "arch_timer", arch_timer_evt);
1263 free_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_SECURE_PPI],
1267 case ARCH_TIMER_HYP_PPI:
1268 err = request_percpu_irq(ppi, arch_timer_handler_phys,
1269 "arch_timer", arch_timer_evt);
1276 pr_err("can't register interrupt %d (%d)\n", ppi, err);
1280 err = arch_timer_cpu_pm_init();
1282 goto out_unreg_notify;
1284 /* Register and immediately configure the timer on the boot CPU */
1285 err = cpuhp_setup_state(CPUHP_AP_ARM_ARCH_TIMER_STARTING,
1286 "clockevents/arm/arch_timer:starting",
1287 arch_timer_starting_cpu, arch_timer_dying_cpu);
1289 goto out_unreg_cpupm;
1293 arch_timer_cpu_pm_deinit();
1296 free_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], arch_timer_evt);
1297 if (arch_timer_has_nonsecure_ppi())
1298 free_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI],
1302 free_percpu(arch_timer_evt);
1303 arch_timer_evt = NULL;
1308 static int __init arch_timer_mem_register(void __iomem *base, unsigned int irq)
1313 arch_timer_mem = kzalloc(sizeof(*arch_timer_mem), GFP_KERNEL);
1314 if (!arch_timer_mem)
1317 arch_timer_mem->base = base;
1318 arch_timer_mem->evt.irq = irq;
1319 __arch_timer_setup(ARCH_TIMER_TYPE_MEM, &arch_timer_mem->evt);
1321 if (arch_timer_mem_use_virtual)
1322 func = arch_timer_handler_virt_mem;
1324 func = arch_timer_handler_phys_mem;
1326 ret = request_irq(irq, func, IRQF_TIMER, "arch_mem_timer", &arch_timer_mem->evt);
1328 pr_err("Failed to request mem timer irq\n");
1329 kfree(arch_timer_mem);
1330 arch_timer_mem = NULL;
1336 static const struct of_device_id arch_timer_of_match[] __initconst = {
1337 { .compatible = "arm,armv7-timer", },
1338 { .compatible = "arm,armv8-timer", },
1342 static const struct of_device_id arch_timer_mem_of_match[] __initconst = {
1343 { .compatible = "arm,armv7-timer-mem", },
1347 static bool __init arch_timer_needs_of_probing(void)
1349 struct device_node *dn;
1350 bool needs_probing = false;
1351 unsigned int mask = ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM;
1353 /* We have two timers, and both device-tree nodes are probed. */
1354 if ((arch_timers_present & mask) == mask)
1358 * Only one type of timer is probed,
1359 * check if we have another type of timer node in device-tree.
1361 if (arch_timers_present & ARCH_TIMER_TYPE_CP15)
1362 dn = of_find_matching_node(NULL, arch_timer_mem_of_match);
1364 dn = of_find_matching_node(NULL, arch_timer_of_match);
1366 if (dn && of_device_is_available(dn))
1367 needs_probing = true;
1371 return needs_probing;
1374 static int __init arch_timer_common_init(void)
1376 arch_timer_banner(arch_timers_present);
1377 arch_counter_register(arch_timers_present);
1378 return arch_timer_arch_init();
1382 * arch_timer_select_ppi() - Select suitable PPI for the current system.
1384 * If HYP mode is available, we know that the physical timer
1385 * has been configured to be accessible from PL1. Use it, so
1386 * that a guest can use the virtual timer instead.
1388 * On ARMv8.1 with VH extensions, the kernel runs in HYP. VHE
1389 * accesses to CNTP_*_EL1 registers are silently redirected to
1390 * their CNTHP_*_EL2 counterparts, and use a different PPI
1393 * If no interrupt provided for virtual timer, we'll have to
1394 * stick to the physical timer. It'd better be accessible...
1395 * For arm64 we never use the secure interrupt.
1397 * Return: a suitable PPI type for the current system.
1399 static enum arch_timer_ppi_nr __init arch_timer_select_ppi(void)
1401 if (is_kernel_in_hyp_mode())
1402 return ARCH_TIMER_HYP_PPI;
1404 if (!is_hyp_mode_available() && arch_timer_ppi[ARCH_TIMER_VIRT_PPI])
1405 return ARCH_TIMER_VIRT_PPI;
1407 if (IS_ENABLED(CONFIG_ARM64))
1408 return ARCH_TIMER_PHYS_NONSECURE_PPI;
1410 return ARCH_TIMER_PHYS_SECURE_PPI;
1413 static void __init arch_timer_populate_kvm_info(void)
1415 arch_timer_kvm_info.virtual_irq = arch_timer_ppi[ARCH_TIMER_VIRT_PPI];
1416 if (is_kernel_in_hyp_mode())
1417 arch_timer_kvm_info.physical_irq = arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI];
1420 static int __init arch_timer_of_init(struct device_node *np)
1426 if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
1427 pr_warn("multiple nodes in dt, skipping\n");
1431 arch_timers_present |= ARCH_TIMER_TYPE_CP15;
1433 has_names = of_property_read_bool(np, "interrupt-names");
1435 for (i = ARCH_TIMER_PHYS_SECURE_PPI; i < ARCH_TIMER_MAX_TIMER_PPI; i++) {
1437 irq = of_irq_get_byname(np, arch_timer_ppi_names[i]);
1439 irq = of_irq_get(np, i);
1441 arch_timer_ppi[i] = irq;
1444 arch_timer_populate_kvm_info();
1446 rate = arch_timer_get_cntfrq();
1447 arch_timer_of_configure_rate(rate, np);
1449 arch_timer_c3stop = !of_property_read_bool(np, "always-on");
1451 /* Check for globally applicable workarounds */
1452 arch_timer_check_ool_workaround(ate_match_dt, np);
1455 * If we cannot rely on firmware initializing the timer registers then
1456 * we should use the physical timers instead.
1458 if (IS_ENABLED(CONFIG_ARM) &&
1459 of_property_read_bool(np, "arm,cpu-registers-not-fw-configured"))
1460 arch_timer_uses_ppi = ARCH_TIMER_PHYS_SECURE_PPI;
1462 arch_timer_uses_ppi = arch_timer_select_ppi();
1464 if (!arch_timer_ppi[arch_timer_uses_ppi]) {
1465 pr_err("No interrupt available, giving up\n");
1469 /* On some systems, the counter stops ticking when in suspend. */
1470 arch_counter_suspend_stop = of_property_read_bool(np,
1471 "arm,no-tick-in-suspend");
1473 ret = arch_timer_register();
1477 if (arch_timer_needs_of_probing())
1480 return arch_timer_common_init();
1482 TIMER_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init);
1483 TIMER_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init);
1486 arch_timer_mem_frame_get_cntfrq(struct arch_timer_mem_frame *frame)
1491 base = ioremap(frame->cntbase, frame->size);
1493 pr_err("Unable to map frame @ %pa\n", &frame->cntbase);
1497 rate = readl_relaxed(base + CNTFRQ);
1504 static struct arch_timer_mem_frame * __init
1505 arch_timer_mem_find_best_frame(struct arch_timer_mem *timer_mem)
1507 struct arch_timer_mem_frame *frame, *best_frame = NULL;
1508 void __iomem *cntctlbase;
1512 cntctlbase = ioremap(timer_mem->cntctlbase, timer_mem->size);
1514 pr_err("Can't map CNTCTLBase @ %pa\n",
1515 &timer_mem->cntctlbase);
1519 cnttidr = readl_relaxed(cntctlbase + CNTTIDR);
1522 * Try to find a virtual capable frame. Otherwise fall back to a
1523 * physical capable frame.
1525 for (i = 0; i < ARCH_TIMER_MEM_MAX_FRAMES; i++) {
1526 u32 cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT |
1527 CNTACR_RWVT | CNTACR_RVOFF | CNTACR_RVCT;
1529 frame = &timer_mem->frame[i];
1533 /* Try enabling everything, and see what sticks */
1534 writel_relaxed(cntacr, cntctlbase + CNTACR(i));
1535 cntacr = readl_relaxed(cntctlbase + CNTACR(i));
1537 if ((cnttidr & CNTTIDR_VIRT(i)) &&
1538 !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT))) {
1540 arch_timer_mem_use_virtual = true;
1544 if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT))
1550 iounmap(cntctlbase);
1556 arch_timer_mem_frame_register(struct arch_timer_mem_frame *frame)
1561 if (arch_timer_mem_use_virtual)
1562 irq = frame->virt_irq;
1564 irq = frame->phys_irq;
1567 pr_err("Frame missing %s irq.\n",
1568 arch_timer_mem_use_virtual ? "virt" : "phys");
1572 if (!request_mem_region(frame->cntbase, frame->size,
1576 base = ioremap(frame->cntbase, frame->size);
1578 pr_err("Can't map frame's registers\n");
1582 ret = arch_timer_mem_register(base, irq);
1588 arch_timers_present |= ARCH_TIMER_TYPE_MEM;
1593 static int __init arch_timer_mem_of_init(struct device_node *np)
1595 struct arch_timer_mem *timer_mem;
1596 struct arch_timer_mem_frame *frame;
1597 struct device_node *frame_node;
1598 struct resource res;
1602 timer_mem = kzalloc(sizeof(*timer_mem), GFP_KERNEL);
1606 if (of_address_to_resource(np, 0, &res))
1608 timer_mem->cntctlbase = res.start;
1609 timer_mem->size = resource_size(&res);
1611 for_each_available_child_of_node(np, frame_node) {
1613 struct arch_timer_mem_frame *frame;
1615 if (of_property_read_u32(frame_node, "frame-number", &n)) {
1616 pr_err(FW_BUG "Missing frame-number.\n");
1617 of_node_put(frame_node);
1620 if (n >= ARCH_TIMER_MEM_MAX_FRAMES) {
1621 pr_err(FW_BUG "Wrong frame-number, only 0-%u are permitted.\n",
1622 ARCH_TIMER_MEM_MAX_FRAMES - 1);
1623 of_node_put(frame_node);
1626 frame = &timer_mem->frame[n];
1629 pr_err(FW_BUG "Duplicated frame-number.\n");
1630 of_node_put(frame_node);
1634 if (of_address_to_resource(frame_node, 0, &res)) {
1635 of_node_put(frame_node);
1638 frame->cntbase = res.start;
1639 frame->size = resource_size(&res);
1641 frame->virt_irq = irq_of_parse_and_map(frame_node,
1642 ARCH_TIMER_VIRT_SPI);
1643 frame->phys_irq = irq_of_parse_and_map(frame_node,
1644 ARCH_TIMER_PHYS_SPI);
1646 frame->valid = true;
1649 frame = arch_timer_mem_find_best_frame(timer_mem);
1651 pr_err("Unable to find a suitable frame in timer @ %pa\n",
1652 &timer_mem->cntctlbase);
1657 rate = arch_timer_mem_frame_get_cntfrq(frame);
1658 arch_timer_of_configure_rate(rate, np);
1660 ret = arch_timer_mem_frame_register(frame);
1661 if (!ret && !arch_timer_needs_of_probing())
1662 ret = arch_timer_common_init();
1667 TIMER_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
1668 arch_timer_mem_of_init);
1670 #ifdef CONFIG_ACPI_GTDT
1672 arch_timer_mem_verify_cntfrq(struct arch_timer_mem *timer_mem)
1674 struct arch_timer_mem_frame *frame;
1678 for (i = 0; i < ARCH_TIMER_MEM_MAX_FRAMES; i++) {
1679 frame = &timer_mem->frame[i];
1684 rate = arch_timer_mem_frame_get_cntfrq(frame);
1685 if (rate == arch_timer_rate)
1688 pr_err(FW_BUG "CNTFRQ mismatch: frame @ %pa: (0x%08lx), CPU: (0x%08lx)\n",
1690 (unsigned long)rate, (unsigned long)arch_timer_rate);
1698 static int __init arch_timer_mem_acpi_init(int platform_timer_count)
1700 struct arch_timer_mem *timers, *timer;
1701 struct arch_timer_mem_frame *frame, *best_frame = NULL;
1702 int timer_count, i, ret = 0;
1704 timers = kcalloc(platform_timer_count, sizeof(*timers),
1709 ret = acpi_arch_timer_mem_init(timers, &timer_count);
1710 if (ret || !timer_count)
1714 * While unlikely, it's theoretically possible that none of the frames
1715 * in a timer expose the combination of feature we want.
1717 for (i = 0; i < timer_count; i++) {
1720 frame = arch_timer_mem_find_best_frame(timer);
1724 ret = arch_timer_mem_verify_cntfrq(timer);
1726 pr_err("Disabling MMIO timers due to CNTFRQ mismatch\n");
1730 if (!best_frame) /* implies !frame */
1732 * Only complain about missing suitable frames if we
1733 * haven't already found one in a previous iteration.
1735 pr_err("Unable to find a suitable frame in timer @ %pa\n",
1736 &timer->cntctlbase);
1740 ret = arch_timer_mem_frame_register(best_frame);
1746 /* Initialize per-processor generic timer and memory-mapped timer(if present) */
1747 static int __init arch_timer_acpi_init(struct acpi_table_header *table)
1749 int ret, platform_timer_count;
1751 if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
1752 pr_warn("already initialized, skipping\n");
1756 arch_timers_present |= ARCH_TIMER_TYPE_CP15;
1758 ret = acpi_gtdt_init(table, &platform_timer_count);
1762 arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI] =
1763 acpi_gtdt_map_ppi(ARCH_TIMER_PHYS_NONSECURE_PPI);
1765 arch_timer_ppi[ARCH_TIMER_VIRT_PPI] =
1766 acpi_gtdt_map_ppi(ARCH_TIMER_VIRT_PPI);
1768 arch_timer_ppi[ARCH_TIMER_HYP_PPI] =
1769 acpi_gtdt_map_ppi(ARCH_TIMER_HYP_PPI);
1771 arch_timer_populate_kvm_info();
1774 * When probing via ACPI, we have no mechanism to override the sysreg
1775 * CNTFRQ value. This *must* be correct.
1777 arch_timer_rate = arch_timer_get_cntfrq();
1778 ret = validate_timer_rate();
1780 pr_err(FW_BUG "frequency not available.\n");
1784 arch_timer_uses_ppi = arch_timer_select_ppi();
1785 if (!arch_timer_ppi[arch_timer_uses_ppi]) {
1786 pr_err("No interrupt available, giving up\n");
1790 /* Always-on capability */
1791 arch_timer_c3stop = acpi_gtdt_c3stop(arch_timer_uses_ppi);
1793 /* Check for globally applicable workarounds */
1794 arch_timer_check_ool_workaround(ate_match_acpi_oem_info, table);
1796 ret = arch_timer_register();
1800 if (platform_timer_count &&
1801 arch_timer_mem_acpi_init(platform_timer_count))
1802 pr_err("Failed to initialize memory-mapped timer.\n");
1804 return arch_timer_common_init();
1806 TIMER_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init);
1809 int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *ts,
1810 enum clocksource_ids *cs_id)
1812 struct arm_smccc_res hvc_res;
1816 if (!IS_ENABLED(CONFIG_HAVE_ARM_SMCCC_DISCOVERY))
1819 if (arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI)
1820 ptp_counter = KVM_PTP_VIRT_COUNTER;
1822 ptp_counter = KVM_PTP_PHYS_COUNTER;
1824 arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID,
1825 ptp_counter, &hvc_res);
1827 if ((int)(hvc_res.a0) < 0)
1830 ktime = (u64)hvc_res.a0 << 32 | hvc_res.a1;
1831 *ts = ktime_to_timespec64(ktime);
1833 *cycle = (u64)hvc_res.a2 << 32 | hvc_res.a3;
1835 *cs_id = CSID_ARM_ARCH_COUNTER;
1839 EXPORT_SYMBOL_GPL(kvm_arch_ptp_get_crosststamp);