xref: /netbsd-src/sys/arch/hpc/stand/hpcboot/sh3/sh_mmu.cpp (revision 2e968e7e378f35a6650e078ce1365e521ec23548)
1 /*	$NetBSD: sh_mmu.cpp,v 1.2 2002/02/04 17:38:27 uch Exp $	*/
2 
3 /*-
4  * Copyright (c) 2001, 2002 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by UCHIYAMA Yasushi.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <sh3/sh_arch.h>
40 #include <sh3/sh_mmu.h>
41 
42 BOOL
43 MemoryManager_SHMMU::init(void)
44 {
45 
46 	_kmode = SetKMode(1);
47 
48 	_asid = VOLATILE_REF(MMUPTEH) & MMUPTEH_ASID_MASK;
49 	DPRINTF((TEXT("ASID = %d\n"), _asid));
50 
51 	return TRUE;
52 }
53 
54 MemoryManager_SHMMU::~MemoryManager_SHMMU(void)
55 {
56 
57 	SetKMode(_kmode);
58 }
59 
60 // get physical address from memory mapped TLB.
61 paddr_t
62 MemoryManager_SHMMU::searchPage(vaddr_t vaddr)
63 {
64 	u_int32_t vpn, idx, s, dum, aae, dae, entry_idx;
65 	paddr_t paddr = ~0;
66 	int way;
67 
68 	vpn = vaddr & SH3_PAGE_MASK;
69 	// Windows CE uses VPN-only index-mode.
70 	idx = vaddr & MMUAA_VPN_MASK;
71 
72 	// to avoid another TLB access, disable external interrupt.
73 	s = suspendIntr();
74 
75 	do {
76 		// load target address page to TLB
77 		dum = VOLATILE_REF(vaddr);
78 		VOLATILE_REF(vaddr) = dum;
79 
80 		for (way = 0; way < MMU_WAY; way++) {
81 			entry_idx = idx | (way << MMUAA_WAY_SHIFT);
82 			// inquire MMU address array.
83 			aae = VOLATILE_REF(MMUAA | entry_idx);
84 
85 			if (!(aae & MMUAA_D_VALID) ||
86 			    ((aae & MMUAA_D_ASID_MASK) != _asid) ||
87 			    (((aae | idx) & SH3_PAGE_MASK) != vpn))
88 				continue;
89 
90 			// entry found.
91 			// inquire MMU data array to get its physical address.
92 			dae = VOLATILE_REF(MMUDA | entry_idx);
93 			paddr = (dae & SH3_PAGE_MASK) | (vaddr & ~SH3_PAGE_MASK);
94 			break;
95 		}
96 	} while (paddr == ~0);
97 
98 	resumeIntr(s);
99 
100 	return paddr;
101 }
102 
103