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/* SPDX-License-Identifier: GPL-2.0-only *//* * arch/arm64/include/asm/arch_timer.h * * Copyright (C) 2012 ARM Ltd. * Author: Marc Zyngier <marc.zyngier@arm.com> */#ifndef __ASM_ARCH_TIMER_H#define __ASM_ARCH_TIMER_H #include <asm/barrier.h>#include <asm/hwcap.h>#include <asm/sysreg.h> #include <linux/bug.h>#include <linux/init.h>#include <linux/jump_label.h>#include <linux/percpu.h>#include <linux/types.h> #include <clocksource/arm_arch_timer.h> #if IS_ENABLED(CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND)#define has_erratum_handler(h)						\	({								\		const struct arch_timer_erratum_workaround *__wa;	\		__wa = __this_cpu_read(timer_unstable_counter_workaround); \		(__wa && __wa->h);					\	}) #define erratum_handler(h)						\	({								\		const struct arch_timer_erratum_workaround *__wa;	\		__wa = __this_cpu_read(timer_unstable_counter_workaround); \		(__wa && __wa->h) ? ({ isb(); __wa->h;}) : arch_timer_##h; \	}) #else#define has_erratum_handler(h)			   false#define erratum_handler(h)			   (arch_timer_##h)#endif enum arch_timer_erratum_match_type {	ate_match_dt,	ate_match_local_cap_id,	ate_match_acpi_oem_info,}; struct clock_event_device; struct arch_timer_erratum_workaround {	enum arch_timer_erratum_match_type match_type;	const void *id;	const char *desc;	u64 (*read_cntpct_el0)(void);	u64 (*read_cntvct_el0)(void);	int (*set_next_event_phys)(unsigned long, struct clock_event_device *);	int (*set_next_event_virt)(unsigned long, struct clock_event_device *);	bool disable_compat_vdso;}; DECLARE_PER_CPU(const struct arch_timer_erratum_workaround *,		timer_unstable_counter_workaround); static inline notrace u64 arch_timer_read_cntpct_el0(void){	u64 cnt; 	asm volatile(ALTERNATIVE("isb\n mrs %0, cntpct_el0",				 "nop\n" __mrs_s("%0", SYS_CNTPCTSS_EL0),				 ARM64_HAS_ECV)		     : "=r" (cnt)); 	return cnt;} static inline notrace u64 arch_timer_read_cntvct_el0(void){	u64 cnt; 	asm volatile(ALTERNATIVE("isb\n mrs %0, cntvct_el0",				 "nop\n" __mrs_s("%0", SYS_CNTVCTSS_EL0),				 ARM64_HAS_ECV)		     : "=r" (cnt)); 	return cnt;} #define arch_timer_reg_read_stable(reg)					\	({								\		erratum_handler(read_ ## reg)();			\	}) /* * These register accessors are marked inline so the compiler can * nicely work out which register we want, and chuck away the rest of * the code. */static __always_inlinevoid arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u64 val){	if (access == ARCH_TIMER_PHYS_ACCESS) {		switch (reg) {		case ARCH_TIMER_REG_CTRL:			write_sysreg(val, cntp_ctl_el0);			isb();			break;		case ARCH_TIMER_REG_CVAL:			write_sysreg(val, cntp_cval_el0);			break;		default:			BUILD_BUG();		}	} else if (access == ARCH_TIMER_VIRT_ACCESS) {		switch (reg) {		case ARCH_TIMER_REG_CTRL:			write_sysreg(val, cntv_ctl_el0);			isb();			break;		case ARCH_TIMER_REG_CVAL:			write_sysreg(val, cntv_cval_el0);			break;		default:			BUILD_BUG();		}	} else {		BUILD_BUG();	}} static __always_inlineu64 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg){	if (access == ARCH_TIMER_PHYS_ACCESS) {		switch (reg) {		case ARCH_TIMER_REG_CTRL:			return read_sysreg(cntp_ctl_el0);		default:			BUILD_BUG();		}	} else if (access == ARCH_TIMER_VIRT_ACCESS) {		switch (reg) {		case ARCH_TIMER_REG_CTRL:			return read_sysreg(cntv_ctl_el0);		default:			BUILD_BUG();		}	} 	BUILD_BUG();	unreachable();} static inline u32 arch_timer_get_cntfrq(void){	return read_sysreg(cntfrq_el0);} static inline u32 arch_timer_get_cntkctl(void){	return read_sysreg(cntkctl_el1);} static inline void arch_timer_set_cntkctl(u32 cntkctl){	write_sysreg(cntkctl, cntkctl_el1);	isb();} static __always_inline u64 __arch_counter_get_cntpct_stable(void){	u64 cnt; 	cnt = arch_timer_reg_read_stable(cntpct_el0);	arch_counter_enforce_ordering(cnt);	return cnt;} static __always_inline u64 __arch_counter_get_cntpct(void){	u64 cnt = arch_timer_read_cntpct_el0(); 	arch_counter_enforce_ordering(cnt);	return cnt;} static __always_inline u64 __arch_counter_get_cntvct_stable(void){	u64 cnt; 	cnt = arch_timer_reg_read_stable(cntvct_el0);	arch_counter_enforce_ordering(cnt);	return cnt;} static __always_inline u64 __arch_counter_get_cntvct(void){	u64 cnt = arch_timer_read_cntvct_el0(); 	arch_counter_enforce_ordering(cnt);	return cnt;} static inline int arch_timer_arch_init(void){	return 0;} static inline void arch_timer_set_evtstrm_feature(void){	cpu_set_named_feature(EVTSTRM);#ifdef CONFIG_COMPAT	compat_elf_hwcap |= COMPAT_HWCAP_EVTSTRM;#endif} static inline bool arch_timer_have_evtstrm_feature(void){	return cpu_have_named_feature(EVTSTRM);}#endif