i386/include/cpufunc.h

/*-
 * Copyright (c) 1993 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD: head/sys/i386/include/cpufunc.h 181911 2008-08-20 09:16:46Z kmacy $
 */

/*
 * Functions to provide access to special i386 instructions.
 * This in included in sys/systm.h, and that file should be
 * used in preference to this.
 */

#ifndef _MACHINE_CPUFUNC_H_
#define	_MACHINE_CPUFUNC_H_

#ifndef _SYS_CDEFS_H_
#error this file needs sys/cdefs.h as a prerequisite
#endif

#ifdef XEN
extern void xen_cli(void);
extern void xen_sti(void);
extern void xen_load_cr3(u_int data);
extern void xen_tlb_flush(void);
extern void xen_invlpg(u_int addr);
extern int xen_save_and_cli(void);
extern void xen_restore_flags(u_int eflags);
#endif

struct region_descriptor;

#define readb(va)	(*(volatile u_int8_t *) (va))
#define readw(va)	(*(volatile u_int16_t *) (va))
#define readl(va)	(*(volatile u_int32_t *) (va))

#define writeb(va, d)	(*(volatile u_int8_t *) (va) = (d))
#define writew(va, d)	(*(volatile u_int16_t *) (va) = (d))
#define writel(va, d)	(*(volatile u_int32_t *) (va) = (d))

#if defined(__GNUCLIKE_ASM) && defined(__CC_SUPPORTS___INLINE)

static __inline void
breakpoint(void)
{
	__asm __volatile("int $3");
}

static __inline u_int
bsfl(u_int mask)
{
	u_int	result;

	__asm __volatile("bsfl %1,%0" : "=r" (result) : "rm" (mask));
	return (result);
}

static __inline u_int
bsrl(u_int mask)
{
	u_int	result;

	__asm __volatile("bsrl %1,%0" : "=r" (result) : "rm" (mask));
	return (result);
}

static __inline void
disable_intr(void)
{
#ifdef XEN
	xen_cli();
#else
    __asm __volatile("cli" : : : "memory");
#endif
}

static __inline void
do_cpuid(u_int ax, u_int *p)
{
	__asm __volatile("cpuid"
			 : "=a" (p[0]), "=b" (p[1]), "=c" (p[2]), "=d" (p[3])
			 :  "0" (ax));
}

static __inline void
cpuid_count(u_int ax, u_int cx, u_int *p)
{
	__asm __volatile("cpuid"
			 : "=a" (p[0]), "=b" (p[1]), "=c" (p[2]), "=d" (p[3])
			 :  "0" (ax), "c" (cx));
}

static __inline void
enable_intr(void)
{
#ifdef XEN
	xen_sti();
#else
	__asm __volatile("sti");
#endif
}

static inline void
cpu_monitor(const void *addr, int extensions, int hints)
{
	__asm __volatile("monitor;"
	    : :"a" (addr), "c" (extensions), "d"(hints));
}

static inline void
cpu_mwait(int extensions, int hints)
{
	__asm __volatile("mwait;" : :"a" (hints), "c" (extensions));
}

#ifdef _KERNEL

#define	HAVE_INLINE_FFS

static __inline int
ffs(int mask)
{
	/*
	 * Note that gcc-2's builtin ffs would be used if we didn't declare
	 * this inline or turn off the builtin.  The builtin is faster but
	 * broken in gcc-2.4.5 and slower but working in gcc-2.5 and later
	 * versions.
	 */
	 return (mask == 0 ? mask : (int)bsfl((u_int)mask) + 1);
}

#define	HAVE_INLINE_FLS

static __inline int
fls(int mask)
{
	return (mask == 0 ? mask : (int)bsrl((u_int)mask) + 1);
}

#endif /* _KERNEL */

static __inline void
halt(void)
{
	__asm __volatile("hlt");
}

#if !defined(__GNUCLIKE_BUILTIN_CONSTANT_P) || __GNUCLIKE_ASM < 3

#define	inb(port)		inbv(port)
#define	outb(port, data)	outbv(port, data)

#else /* __GNUCLIKE_BUILTIN_CONSTANT_P && __GNUCLIKE_ASM >= 3 */

/*
 * The following complications are to get around gcc not having a
 * constraint letter for the range 0..255.  We still put "d" in the
 * constraint because "i" isn't a valid constraint when the port
 * isn't constant.  This only matters for -O0 because otherwise
 * the non-working version gets optimized away.
 *
 * Use an expression-statement instead of a conditional expression
 * because gcc-2.6.0 would promote the operands of the conditional
 * and produce poor code for "if ((inb(var) & const1) == const2)".
 *
 * The unnecessary test `(port) < 0x10000' is to generate a warning if
 * the `port' has type u_short or smaller.  Such types are pessimal.
 * This actually only works for signed types.  The range check is
 * careful to avoid generating warnings.
 */
#define	inb(port) __extension__ ({					\
	u_char	_data;							\
	if (__builtin_constant_p(port) && ((port) & 0xffff) < 0x100	\
	    && (port) < 0x10000)					\
		_data = inbc(port);					\
	else								\
		_data = inbv(port);					\
	_data; })

#define	outb(port, data) (						\
	__builtin_constant_p(port) && ((port) & 0xffff) < 0x100		\
	&& (port) < 0x10000						\
	? outbc(port, data) : outbv(port, data))

static __inline u_char
inbc(u_int port)
{
	u_char	data;

	__asm __volatile("inb %1,%0" : "=a" (data) : "id" ((u_short)(port)));
	return (data);
}

static __inline void
outbc(u_int port, u_char data)
{
	__asm __volatile("outb %0,%1" : : "a" (data), "id" ((u_short)(port)));
}

#endif /* __GNUCLIKE_BUILTIN_CONSTANT_P  && __GNUCLIKE_ASM >= 3*/

static __inline u_char
inbv(u_int port)
{
	u_char	data;
	/*
	 * We use %%dx and not %1 here because i/o is done at %dx and not at
	 * %edx, while gcc generates inferior code (movw instead of movl)
	 * if we tell it to load (u_short) port.
	 */
	__asm __volatile("inb %%dx,%0" : "=a" (data) : "d" (port));
	return (data);
}

static __inline u_int
inl(u_int port)
{
	u_int	data;

	__asm __volatile("inl %%dx,%0" : "=a" (data) : "d" (port));
	return (data);
}

static __inline void
insb(u_int port, void *addr, size_t cnt)
{
	__asm __volatile("cld; rep; insb"
			 : "+D" (addr), "+c" (cnt)
			 : "d" (port)
			 : "memory");
}

static __inline void
insw(u_int port, void *addr, size_t cnt)
{
	__asm __volatile("cld; rep; insw"
			 : "+D" (addr), "+c" (cnt)
			 : "d" (port)
			 : "memory");
}

static __inline void
insl(u_int port, void *addr, size_t cnt)
{
	__asm __volatile("cld; rep; insl"
			 : "+D" (addr), "+c" (cnt)
			 : "d" (port)
			 : "memory");
}

static __inline void
invd(void)
{
	__asm __volatile("invd");
}

static __inline u_short
inw(u_int port)
{
	u_short	data;

	__asm __volatile("inw %%dx,%0" : "=a" (data) : "d" (port));
	return (data);
}

static __inline void
outbv(u_int port, u_char data)
{
	u_char	al;
	/*
	 * Use an unnecessary assignment to help gcc's register allocator.
	 * This make a large difference for gcc-1.40 and a tiny difference
	 * for gcc-2.6.0.  For gcc-1.40, al had to be ``asm("ax")'' for
	 * best results.  gcc-2.6.0 can't handle this.
	 */
	al = data;
	__asm __volatile("outb %0,%%dx" : : "a" (al), "d" (port));
}

static __inline void
outl(u_int port, u_int data)
{
	/*
	 * outl() and outw() aren't used much so we haven't looked at
	 * possible micro-optimizations such as the unnecessary
	 * assignment for them.
	 */
	__asm __volatile("outl %0,%%dx" : : "a" (data), "d" (port));
}

static __inline void
outsb(u_int port, const void *addr, size_t cnt)
{
	__asm __volatile("cld; rep; outsb"
			 : "+S" (addr), "+c" (cnt)
			 : "d" (port));
}

static __inline void
outsw(u_int port, const void *addr, size_t cnt)
{
	__asm __volatile("cld; rep; outsw"
			 : "+S" (addr), "+c" (cnt)
			 : "d" (port));
}

static __inline void
outsl(u_int port, const void *addr, size_t cnt)
{
	__asm __volatile("cld; rep; outsl"
			 : "+S" (addr), "+c" (cnt)
			 : "d" (port));
}

static __inline void
outw(u_int port, u_short data)
{
	__asm __volatile("outw %0,%%dx" : : "a" (data), "d" (port));
}

static __inline void
ia32_pause(void)
{
	__asm __volatile("pause");
}

static __inline u_int
read_eflags(void)
{
	u_int	ef;

	__asm __volatile("pushfl; popl %0" : "=r" (ef));
	return (ef);
}

static __inline uint64_t
rdmsr(u_int msr)
{
	uint64_t rv;

	__asm __volatile("rdmsr" : "=A" (rv) : "c" (msr));
	return (rv);
}

static __inline uint64_t
rdpmc(u_int pmc)
{
	uint64_t rv;

	__asm __volatile("rdpmc" : "=A" (rv) : "c" (pmc));
	return (rv);
}

static __inline uint64_t
rdtsc(void)
{
	uint64_t rv;

	__asm __volatile("rdtsc" : "=A" (rv));
	return (rv);
}

static __inline void
wbinvd(void)
{
	__asm __volatile("wbinvd");
}

static __inline void
write_eflags(u_int ef)
{
	__asm __volatile("pushl %0; popfl" : : "r" (ef));
}

static __inline void
wrmsr(u_int msr, uint64_t newval)
{
	__asm __volatile("wrmsr" : : "A" (newval), "c" (msr));
}

static __inline void
load_cr0(u_int data)
{

	__asm __volatile("movl %0,%%cr0" : : "r" (data));
}

static __inline u_int
rcr0(void)
{
	u_int	data;

	__asm __volatile("movl %%cr0,%0" : "=r" (data));
	return (data);
}

static __inline u_int
rcr2(void)
{
	u_int	data;

	__asm __volatile("movl %%cr2,%0" : "=r" (data));
	return (data);
}

static __inline void
load_cr3(u_int data)
{
#ifdef XEN
	xen_load_cr3(data);
#else
	__asm __volatile("movl %0,%%cr3" : : "r" (data) : "memory");
#endif
}

static __inline u_int
rcr3(void)
{
	u_int	data;

	__asm __volatile("movl %%cr3,%0" : "=r" (data));
	return (data);
}

static __inline void
load_cr4(u_int data)
{
	__asm __volatile("movl %0,%%cr4" : : "r" (data));
}

static __inline u_int
rcr4(void)
{
	u_int	data;

	__asm __volatile("movl %%cr4,%0" : "=r" (data));
	return (data);
}

/*
 * Global TLB flush (except for thise for pages marked PG_G)
 */
static __inline void
invltlb(void)
{
#ifdef XEN
	xen_tlb_flush();
#else
	load_cr3(rcr3());
#endif
}

/*
 * TLB flush for an individual page (even if it has PG_G).
 * Only works on 486+ CPUs (i386 does not have PG_G).
 */
static __inline void
invlpg(u_int addr)
{

#ifdef XEN
	xen_invlpg(addr);
#else
	__asm __volatile("invlpg %0" : : "m" (*(char *)addr) : "memory");
#endif
}

static __inline u_int
rfs(void)
{
	u_int sel;
	__asm __volatile("movl %%fs,%0" : "=rm" (sel));
	return (sel);
}

static __inline uint64_t
rgdt(void)
{
	uint64_t gdtr;
	__asm __volatile("sgdt %0" : "=m" (gdtr));
	return (gdtr);
}

static __inline u_int
rgs(void)
{
	u_int sel;
	__asm __volatile("movl %%gs,%0" : "=rm" (sel));
	return (sel);
}

static __inline uint64_t
ridt(void)
{
	uint64_t idtr;
	__asm __volatile("sidt %0" : "=m" (idtr));
	return (idtr);
}

static __inline u_short
rldt(void)
{
	u_short ldtr;
	__asm __volatile("sldt %0" : "=g" (ldtr));
	return (ldtr);
}

static __inline u_int
rss(void)
{
	u_int sel;
	__asm __volatile("movl %%ss,%0" : "=rm" (sel));
	return (sel);
}

static __inline u_short
rtr(void)
{
	u_short tr;
	__asm __volatile("str %0" : "=g" (tr));
	return (tr);
}

static __inline void
load_fs(u_int sel)
{
	__asm __volatile("movl %0,%%fs" : : "rm" (sel));
}

static __inline void
load_gs(u_int sel)
{
	__asm __volatile("movl %0,%%gs" : : "rm" (sel));
}

static __inline void
lidt(struct region_descriptor *addr)
{
	__asm __volatile("lidt (%0)" : : "r" (addr));
}

static __inline void
lldt(u_short sel)
{
	__asm __volatile("lldt %0" : : "r" (sel));
}

static __inline void
ltr(u_short sel)
{
	__asm __volatile("ltr %0" : : "r" (sel));
}

static __inline u_int
rdr0(void)
{
	u_int	data;
	__asm __volatile("movl %%dr0,%0" : "=r" (data));
	return (data);
}

static __inline void
load_dr0(u_int dr0)
{
	__asm __volatile("movl %0,%%dr0" : : "r" (dr0));
}

static __inline u_int
rdr1(void)
{
	u_int	data;
	__asm __volatile("movl %%dr1,%0" : "=r" (data));
	return (data);
}

static __inline void
load_dr1(u_int dr1)
{
	__asm __volatile("movl %0,%%dr1" : : "r" (dr1));
}

static __inline u_int
rdr2(void)
{
	u_int	data;
	__asm __volatile("movl %%dr2,%0" : "=r" (data));
	return (data);
}

static __inline void
load_dr2(u_int dr2)
{
	__asm __volatile("movl %0,%%dr2" : : "r" (dr2));
}

static __inline u_int
rdr3(void)
{
	u_int	data;
	__asm __volatile("movl %%dr3,%0" : "=r" (data));
	return (data);
}

static __inline void
load_dr3(u_int dr3)
{
	__asm __volatile("movl %0,%%dr3" : : "r" (dr3));
}

static __inline u_int
rdr4(void)
{
	u_int	data;
	__asm __volatile("movl %%dr4,%0" : "=r" (data));
	return (data);
}

static __inline void
load_dr4(u_int dr4)
{
	__asm __volatile("movl %0,%%dr4" : : "r" (dr4));
}

static __inline u_int
rdr5(void)
{
	u_int	data;
	__asm __volatile("movl %%dr5,%0" : "=r" (data));
	return (data);
}

static __inline void
load_dr5(u_int dr5)
{
	__asm __volatile("movl %0,%%dr5" : : "r" (dr5));
}

static __inline u_int
rdr6(void)
{
	u_int	data;
	__asm __volatile("movl %%dr6,%0" : "=r" (data));
	return (data);
}

static __inline void
load_dr6(u_int dr6)
{
	__asm __volatile("movl %0,%%dr6" : : "r" (dr6));
}

static __inline u_int
rdr7(void)
{
	u_int	data;
	__asm __volatile("movl %%dr7,%0" : "=r" (data));
	return (data);
}

static __inline void
load_dr7(u_int dr7)
{
	__asm __volatile("movl %0,%%dr7" : : "r" (dr7));
}

static __inline register_t
intr_disable(void)
{
	register_t eflags;

#ifdef XEN
	eflags = xen_save_and_cli();
#else
	eflags = read_eflags();
	disable_intr();
#endif
	return (eflags);
}

static __inline void
intr_restore(register_t eflags)
{
#ifdef XEN
	xen_restore_flags(eflags);
#else
	write_eflags(eflags);
#endif
}

#else /* !(__GNUCLIKE_ASM && __CC_SUPPORTS___INLINE) */

int	breakpoint(void);
u_int	bsfl(u_int mask);
u_int	bsrl(u_int mask);
void	disable_intr(void);
void	do_cpuid(u_int ax, u_int *p);
void	enable_intr(void);
void	halt(void);
void	ia32_pause(void);
u_char	inb(u_int port);
u_int	inl(u_int port);
void	insb(u_int port, void *addr, size_t cnt);
void	insl(u_int port, void *addr, size_t cnt);
void	insw(u_int port, void *addr, size_t cnt);
register_t	intr_disable(void);
void	intr_restore(register_t ef);
void	invd(void);
void	invlpg(u_int addr);
void	invltlb(void);
u_short	inw(u_int port);
void	lidt(struct region_descriptor *addr);
void	lldt(u_short sel);
void	load_cr0(u_int cr0);
void	load_cr3(u_int cr3);
void	load_cr4(u_int cr4);
void	load_dr0(u_int dr0);
void	load_dr1(u_int dr1);
void	load_dr2(u_int dr2);
void	load_dr3(u_int dr3);
void	load_dr4(u_int dr4);
void	load_dr5(u_int dr5);
void	load_dr6(u_int dr6);
void	load_dr7(u_int dr7);
void	load_fs(u_int sel);
void	load_gs(u_int sel);
void	ltr(u_short sel);
void	outb(u_int port, u_char data);
void	outl(u_int port, u_int data);
void	outsb(u_int port, const void *addr, size_t cnt);
void	outsl(u_int port, const void *addr, size_t cnt);
void	outsw(u_int port, const void *addr, size_t cnt);
void	outw(u_int port, u_short data);
u_int	rcr0(void);
u_int	rcr2(void);
u_int	rcr3(void);
u_int	rcr4(void);
uint64_t rdmsr(u_int msr);
uint64_t rdpmc(u_int pmc);
u_int	rdr0(void);
u_int	rdr1(void);
u_int	rdr2(void);
u_int	rdr3(void);
u_int	rdr4(void);
u_int	rdr5(void);
u_int	rdr6(void);
u_int	rdr7(void);
uint64_t rdtsc(void);
u_int	read_eflags(void);
u_int	rfs(void);
uint64_t rgdt(void);
u_int	rgs(void);
uint64_t ridt(void);
u_short	rldt(void);
u_short	rtr(void);
void	wbinvd(void);
void	write_eflags(u_int ef);
void	wrmsr(u_int msr, uint64_t newval);

#endif	/* __GNUCLIKE_ASM && __CC_SUPPORTS___INLINE */

void    reset_dbregs(void);

#ifdef _KERNEL
int	rdmsr_safe(u_int msr, uint64_t *val);
int	wrmsr_safe(u_int msr, uint64_t newval);
#endif

#endif /* !_MACHINE_CPUFUNC_H_ */