1 /* $OpenBSD: k6_mem.c,v 1.7 2006/06/10 18:00:48 gwk Exp $ */
2 /*-
3 * Copyright (c) 1999 Brian Fundakowski Feldman
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 * $FreeBSD: src/sys/i386/i386/k6_mem.c,v 1.4 1999/09/05 15:45:57 green Exp $
28 *
29 */
30
31 #include <sys/param.h>
32 #include <sys/kernel.h>
33 #include <sys/systm.h>
34 #include <sys/ioccom.h>
35 #include <sys/malloc.h>
36 #include <sys/memrange.h>
37
38 #include <machine/cpufunc.h>
39 #include <machine/specialreg.h>
40
41 /*
42 * A K6-2 MTRR is defined as the highest 15 bits having the address, the next
43 * 15 having the mask, the 1st bit being "write-combining" and the 0th bit
44 * being "uncacheable".
45 *
46 * Address Mask WC UC
47 * | XXXXXXXXXXXXXXX | XXXXXXXXXXXXXXX | X | X |
48 *
49 * There are two of these in the 64-bit UWCCR.
50 */
51 #define UWCCR 0xc0000085
52
53 #define k6_reg_get(reg, addr, mask, wc, uc) do { \
54 addr = (reg) & 0xfffe0000; \
55 mask = ((reg) & 0x1fffc) >> 2; \
56 wc = ((reg) & 0x2) >> 1; \
57 uc = (reg) & 0x1; \
58 } while (0)
59
60 #define k6_reg_make(addr, mask, wc, uc) \
61 ((addr) | ((mask) << 2) | ((wc) << 1) | uc)
62
63 void k6_mrinit(struct mem_range_softc *sc);
64 int k6_mrset(struct mem_range_softc *, struct mem_range_desc *, int *);
65 __inline int k6_mrmake(struct mem_range_desc *, u_int32_t *);
66
67 struct mem_range_ops k6_mrops = {
68 k6_mrinit,
69 k6_mrset,
70 NULL
71 };
72
73 __inline int
74 k6_mrmake(struct mem_range_desc *desc, u_int32_t *mtrr)
75 {
76 u_int32_t len = 0, wc, uc;
77 int bit;
78
79 if (desc->mr_base &~ 0xfffe0000)
80 return EINVAL;
81 if (desc->mr_len < 131072 || !powerof2(desc->mr_len))
82 return EINVAL;
83 if (desc->mr_flags &~ (MDF_WRITECOMBINE|MDF_UNCACHEABLE))
84 return EOPNOTSUPP;
85
86 for (bit = ffs(desc->mr_len >> 17) - 1; bit < 15; bit++)
87 len |= 1 << bit;
88 wc = (desc->mr_flags & MDF_WRITECOMBINE) ? 1 : 0;
89 uc = (desc->mr_flags & MDF_UNCACHEABLE) ? 1 : 0;
90
91 *mtrr = k6_reg_make(desc->mr_base, len, wc, uc);
92 return 0;
93 }
94
95 void
96 k6_mrinit(struct mem_range_softc *sc)
97 {
98 u_int64_t reg;
99 u_int32_t addr, mask, wc, uc;
100 int d;
101
102 sc->mr_cap = 0;
103 sc->mr_ndesc = 2; /* XXX (BFF) For now, we only have one msr for this */
104 sc->mr_desc = malloc(sc->mr_ndesc * sizeof(struct mem_range_desc),
105 M_MEMDESC, M_NOWAIT);
106 if (sc->mr_desc == NULL)
107 panic("k6_mrinit: malloc returns NULL");
108
109 bzero(sc->mr_desc, sc->mr_ndesc * sizeof(struct mem_range_desc));
110
111 reg = rdmsr(UWCCR);
112 for (d = 0; d < sc->mr_ndesc; d++) {
113 u_int32_t one = (reg & (0xffffffff << (32 * d))) >> (32 * d);
114
115 k6_reg_get(one, addr, mask, wc, uc);
116 sc->mr_desc[d].mr_base = addr;
117 sc->mr_desc[d].mr_len = ffs(mask) << 17;
118 if (wc)
119 sc->mr_desc[d].mr_flags |= MDF_WRITECOMBINE;
120 if (uc)
121 sc->mr_desc[d].mr_flags |= MDF_UNCACHEABLE;
122 }
123
124 printf("mtrr: K6-family MTRR support (%d registers)\n", sc->mr_ndesc);
125 }
126
127 int
128 k6_mrset(struct mem_range_softc *sc, struct mem_range_desc *desc, int *arg)
129 {
130 u_int64_t reg;
131 u_int32_t mtrr;
132 int error, d;
133
134 switch (*arg) {
135 case MEMRANGE_SET_UPDATE:
136 error = k6_mrmake(desc, &mtrr);
137 if (error)
138 return error;
139 for (d = 0; d < sc->mr_ndesc; d++) {
140 if (!sc->mr_desc[d].mr_len) {
141 sc->mr_desc[d] = *desc;
142 goto out;
143 }
144 if (sc->mr_desc[d].mr_base == desc->mr_base &&
145 sc->mr_desc[d].mr_len == desc->mr_len)
146 return EEXIST;
147 }
148
149 return ENOSPC;
150 case MEMRANGE_SET_REMOVE:
151 mtrr = 0;
152 for (d = 0; d < sc->mr_ndesc; d++)
153 if (sc->mr_desc[d].mr_base == desc->mr_base &&
154 sc->mr_desc[d].mr_len == desc->mr_len) {
155 bzero(&sc->mr_desc[d], sizeof(sc->mr_desc[d]));
156 goto out;
157 }
158
159 return ENOENT;
160 default:
161 return EOPNOTSUPP;
162 }
163
164 out:
165
166 disable_intr();
167 wbinvd();
168 reg = rdmsr(UWCCR);
169 reg &= ~(0xffffffff << (32 * d));
170 reg |= mtrr << (32 * d);
171 wrmsr(UWCCR, reg);
172 wbinvd();
173 enable_intr();
174
175 return 0;
176 }