[deliverable/linux.git] / arch / x86 / include / asm / pvclock.h

#ifndef _ASM_X86_PVCLOCK_H
#define _ASM_X86_PVCLOCK_H

#include <linux/clocksource.h>
#include <asm/pvclock-abi.h>

#ifdef CONFIG_KVM_GUEST
extern struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void);
#else
static inline struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void)
{
	return NULL;
}
#endif

/* some helper functions for xen and kvm pv clock sources */
cycle_t pvclock_clocksource_read(struct pvclock_vcpu_time_info *src);
u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src);
void pvclock_set_flags(u8 flags);
unsigned long pvclock_tsc_khz(struct pvclock_vcpu_time_info *src);
void pvclock_read_wallclock(struct pvclock_wall_clock *wall,
			    struct pvclock_vcpu_time_info *vcpu,
			    struct timespec *ts);
void pvclock_resume(void);

void pvclock_touch_watchdogs(void);

/*
 * Scale a 64-bit delta by scaling and multiplying by a 32-bit fraction,
 * yielding a 64-bit result.
 */
static inline u64 pvclock_scale_delta(u64 delta, u32 mul_frac, int shift)
{
	u64 product;
#ifdef __i386__
	u32 tmp1, tmp2;
#else
	ulong tmp;
#endif

	if (shift < 0)
		delta >>= -shift;
	else
		delta <<= shift;

#ifdef __i386__
	__asm__ (
		"mul  %5       ; "
		"mov  %4,%%eax ; "
		"mov  %%edx,%4 ; "
		"mul  %5       ; "
		"xor  %5,%5    ; "
		"add  %4,%%eax ; "
		"adc  %5,%%edx ; "
		: "=A" (product), "=r" (tmp1), "=r" (tmp2)
		: "a" ((u32)delta), "1" ((u32)(delta >> 32)), "2" (mul_frac) );
#elif defined(__x86_64__)
	__asm__ (
		"mulq %[mul_frac] ; shrd $32, %[hi], %[lo]"
		: [lo]"=a"(product),
		  [hi]"=d"(tmp)
		: "0"(delta),
		  [mul_frac]"rm"((u64)mul_frac));
#else
#error implement me!
#endif

	return product;
}

static __always_inline
u64 pvclock_get_nsec_offset(const struct pvclock_vcpu_time_info *src)
{
	u64 delta = rdtsc_ordered() - src->tsc_timestamp;
	return pvclock_scale_delta(delta, src->tsc_to_system_mul,
				   src->tsc_shift);
}

static __always_inline
unsigned __pvclock_read_cycles(const struct pvclock_vcpu_time_info *src,
			       cycle_t *cycles, u8 *flags)
{
	unsigned version;
	cycle_t ret, offset;
	u8 ret_flags;

	version = src->version;

	offset = pvclock_get_nsec_offset(src);
	ret = src->system_time + offset;
	ret_flags = src->flags;

	*cycles = ret;
	*flags = ret_flags;
	return version;
}

struct pvclock_vsyscall_time_info {
	struct pvclock_vcpu_time_info pvti;
} __attribute__((__aligned__(SMP_CACHE_BYTES)));

#define PVTI_SIZE sizeof(struct pvclock_vsyscall_time_info)

#endif /* _ASM_X86_PVCLOCK_H */
Commit	Line	Data
1965aae3 PA	1	#ifndef _ASM_X86_PVCLOCK_H
1965aae3 PA	2	#define _ASM_X86_PVCLOCK_H
7af192c9 GH	3
	4	#include <linux/clocksource.h>
	5	#include <asm/pvclock-abi.h>
	6
8705d603	7	#ifdef CONFIG_KVM_GUEST
dac16fba AL	8	extern struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void);
	9	#else
	10	static inline struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void)
	11	{
	12	return NULL;
	13	}
	14	#endif
	15
7af192c9 GH	16	/* some helper functions for xen and kvm pv clock sources */
7af192c9 GH	17	cycle_t pvclock_clocksource_read(struct pvclock_vcpu_time_info *src);
2697902b	18	u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src);
424c32f1	19	void pvclock_set_flags(u8 flags);
3807f345	20	unsigned long pvclock_tsc_khz(struct pvclock_vcpu_time_info *src);
7af192c9 GH	21	void pvclock_read_wallclock(struct pvclock_wall_clock *wall,
	22	struct pvclock_vcpu_time_info *vcpu,
	23	struct timespec *ts);
e7a3481c	24	void pvclock_resume(void);
7af192c9	25
d63285e9 MT	26	void pvclock_touch_watchdogs(void);
d63285e9 MT	27
347bb444 ZA	28	/*
	29	* Scale a 64-bit delta by scaling and multiplying by a 32-bit fraction,
	30	* yielding a 64-bit result.
	31	*/
	32	static inline u64 pvclock_scale_delta(u64 delta, u32 mul_frac, int shift)
	33	{
	34	u64 product;
	35	#ifdef __i386__
	36	u32 tmp1, tmp2;
de2d1a52 ZA	37	#else
de2d1a52 ZA	38	ulong tmp;
347bb444 ZA	39	#endif
	40
	41	if (shift < 0)
	42	delta >>= -shift;
	43	else
	44	delta <<= shift;
	45
	46	#ifdef __i386__
	47	__asm__ (
	48	"mul %5 ; "
	49	"mov %4,%%eax ; "
	50	"mov %%edx,%4 ; "
	51	"mul %5 ; "
	52	"xor %5,%5 ; "
	53	"add %4,%%eax ; "
	54	"adc %5,%%edx ; "
	55	: "=A" (product), "=r" (tmp1), "=r" (tmp2)
	56	: "a" ((u32)delta), "1" ((u32)(delta >> 32)), "2" (mul_frac) );
	57	#elif defined(__x86_64__)
	58	__asm__ (
3b217116	59	"mulq %[mul_frac] ; shrd $32, %[hi], %[lo]"
de2d1a52 ZA	60	: [lo]"=a"(product),
	61	[hi]"=d"(tmp)
	62	: "0"(delta),
	63	[mul_frac]"rm"((u64)mul_frac));
347bb444 ZA	64	#else
	65	#error implement me!
	66	#endif
	67
	68	return product;
	69	}
	70
dce2db0a MT	71	static __always_inline
	72	u64 pvclock_get_nsec_offset(const struct pvclock_vcpu_time_info *src)
	73	{
502dfeff	74	u64 delta = rdtsc_ordered() - src->tsc_timestamp;
dce2db0a MT	75	return pvclock_scale_delta(delta, src->tsc_to_system_mul,
	76	src->tsc_shift);
	77	}
	78
	79	static __always_inline
	80	unsigned __pvclock_read_cycles(const struct pvclock_vcpu_time_info *src,
	81	cycle_t cycles, u8 flags)
	82	{
	83	unsigned version;
	84	cycle_t ret, offset;
	85	u8 ret_flags;
	86
	87	version = src->version;
502dfeff	88
dce2db0a MT	89	offset = pvclock_get_nsec_offset(src);
	90	ret = src->system_time + offset;
	91	ret_flags = src->flags;
dce2db0a MT	92
	93	*cycles = ret;
	94	*flags = ret_flags;
	95	return version;
	96	}
	97
71056ae2 MT	98	struct pvclock_vsyscall_time_info {
71056ae2 MT	99	struct pvclock_vcpu_time_info pvti;
71056ae2 MT	100	} __attribute__((__aligned__(SMP_CACHE_BYTES)));
	101
	102	#define PVTI_SIZE sizeof(struct pvclock_vsyscall_time_info)
71056ae2	103
1965aae3	104	#endif /* _ASM_X86_PVCLOCK_H */