xref: /illumos-gate/usr/src/boot/efi/loader/arch/amd64/amd64_tramp.S (revision 9b9d39d2a32ff806d2431dbcc50968ef1e6d46b2)
1/*-
2 * Copyright (c) 2013 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Benno Rice under sponsorship from
6 * the FreeBSD Foundation.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD$
29 */
30
31#include <machine/asmacros.h>
32
33	.text
34	.globl	amd64_tramp
35
36/*
37 * void amd64_tramp(uint64_t stack, void *copy_finish, uint64_t kernend,
38 *		    uint64_t modulep, uint64_t pagetable, uint64_t entry)
39 */
40amd64_tramp:
41	cli			/* Make sure we don't get interrupted. */
42	movq	%rdi,%rsp	/* Switch to our temporary stack. */
43
44	movq	%rdx,%r12	/* Stash the kernel values for later. */
45	movq	%rcx,%r13
46	movq	%r8,%r14
47	movq	%r9,%r15
48
49	callq	*%rsi		/* Call copy_finish so we're all ready to go. */
50
51	pushq	%r12		/* Push kernend. */
52	salq	$32,%r13	/* Shift modulep and push it. */
53	pushq	%r13
54	pushq	%r15		/* Push the entry address. */
55	movq	%r14,%cr3	/* Switch page tables. */
56	ret			/* "Return" to kernel entry. */
57
58	ALIGN_TEXT
59amd64_tramp_end:
60
61	.data
62	.globl	amd64_tramp_size
63amd64_tramp_size:
64	.long	amd64_tramp_end-amd64_tramp
65