xref: /dragonfly/sys/platform/vkernel64/x86_64/locore.s (revision 466d4f43)

/*
 * Copyright (c) 2006 The DragonFly Project.  All rights reserved.
 *
 * This code is derived from software contributed to The DragonFly Project
 * by Matthew Dillon <dillon@backplane.com>
 *
 * 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.
 * 3. Neither the name of The DragonFly Project 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 COPYRIGHT HOLDERS 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
 * COPYRIGHT HOLDERS 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.
 */

#include <sys/syscall.h>
#include <machine/asmacros.h>
#include <machine/psl.h>
#include "assym.s"

	/*
	 * The sysinit and sysuninit sections have to be read-write data
	 * sections, not read-only data sections.
	 */
	.section	set_sysinit_set, "aw"
	.section	set_sysuninit_set, "aw"

	.data
	ALIGN_DATA		/* just to be sure */

	/*
	 * Normally the startup code would begin here, but this is a
	 * virtual kernel so we just have a main() in platform/init.c
	 */

	.text
/**********************************************************************
 *
 * Signal trampoline, copied to top of user stack
 *
 * arguments: %rdi, %rsi, %rdx, %rcx
 */
NON_GPROF_ENTRY(sigcode)
	call	*SIGF_HANDLER(%rsp)	/* call signal handler */
	lea	SIGF_UC(%rsp),%rdi	/* get ucontext_t */
	pushq	$0			/* junk to fake return addr. */
	movq	$SYS_sigreturn,%rax
	syscall				/* enter kernel with args */
0:	hlt				/* trap priviliged instruction */
	jmp	0b

	ALIGN_TEXT
esigcode:

/* void reset_dbregs() */
ENTRY(reset_dbregs)
	movq	$0x200,%rax	/* the manual says that bit 10 must be set to 1 */
	movq	%rax,%dr7	/* disable all breapoints first */
	movq	$0,%rax
	movq	%rax,%dr0
	movq	%rax,%dr1
	movq	%rax,%dr2
	movq	%rax,%dr3
	movq	%rax,%dr6
	ret
END(reset_dbregs)

	.data
	.globl	szsigcode
szsigcode:
	.long	esigcode - sigcode