xref: /titanic_41/usr/src/uts/sun4u/sunfire/ml/fhc_asm.s (revision fcf3ce441efd61da9bb2884968af01cb7c1452cc)
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29#include <sys/param.h>
30#include <sys/errno.h>
31#include <sys/asm_linkage.h>
32#include <sys/machthread.h>
33#include <sys/asi.h>
34#include <sys/privregs.h>
35#include <sys/spitregs.h>
36
37#if defined(lint)
38
39#else	/* lint */
40#include "assym.h"
41#endif	/* lint */
42
43/*
44 * fhc_shutdown_asm(u_longlong_t base, int size)
45 *
46 * Flush cpu E$ then shutdown.
47 * This function is special in that it really sets the D-tags to
48 * a known state.  And this is the behavior we're looking for.
49 *
50 * The flush address is known to be a cpu-unique non-existent
51 * cacheable address.  We write to non-existent memory, using
52 * the side effect of d-tag invalidation.
53 *
54 * Also, note that this function is never run from main memory.
55 * Rather it is copied to non-cacheable SRAM (hence the ..._end
56 * label at the bottom of the function).  This implies that the
57 * function must be position independent code that doesn't reference
58 * cacheable real memory.
59 */
60#if defined(lint)
61
62/*ARGSUSED*/
63void
64fhc_shutdown_asm(u_longlong_t base, int size)
65{}
66
67#else	/* lint */
68
69	ENTRY(fhc_shutdown_asm)
70	! turn off errors (we'll be writing to non-existent memory)
71	stxa	%g0, [%g0]ASI_ESTATE_ERR
72	membar	#Sync			! SYNC
73
74	rdpr	%pstate, %o4
75	andn	%o4, PSTATE_IE | PSTATE_AM, %o3
76	wrpr	%o3, %g0, %pstate
771:
78	brlez,pn %o1, 2f		! if (len <= 0) exit loop
79	  dec	64, %o1			! size -= 64
80        sta     %g0, [%o0]ASI_MEM	! store (unpopulated) word
81	ba	1b
82	  inc	64, %o0			! addr += 64
832:
84	membar  #Sync			! SYNC
85	shutdown			! SHUTDOWN
86	/*NOTREACHED*/
87
88	! if, for some reason, this cpu doesn't shutdown, just sit here
893:
90	ba	3b
91	  nop				! eventually the master will notice
92	SET_SIZE(fhc_shutdown_asm)
93
94	.global	fhc_shutdown_asm_end
95fhc_shutdown_asm_end:
96
97#endif	/* lint */
98