isa_milan.c revision 1.4.10.2 1 /* $NetBSD: isa_milan.c,v 1.4.10.2 2002/02/28 04:08:26 nathanw Exp $ */
2
3 /*-
4 * Copyright (c) 2001 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Leo Weppelman.
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 <sys/types.h>
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/device.h>
43
44 #include <dev/isa/isavar.h>
45 #include <dev/isa/isareg.h>
46
47 #include <machine/iomap.h>
48
49 void isa_bus_init(void);
50
51 static void new_imask(void);
52 static void isa_callback(int);
53
54 /*
55 * Bitmask of currently enabled isa interrupts. Used by new_imask().
56 */
57 static u_int16_t imask_enable = 0xffff;
58
59 #define IRQ_SLAVE 2 /* Slave at level 2 */
60 #define MILAN_MAX_ISA_INTS 16 /* Max. number of vectors */
61 #define ICU_OFFSET 0 /* Interrupt vector base */
62
63 #define WICU(icu, val) *(volatile u_int8_t*)(icu) = val
64
65 static isa_intr_info_t milan_isa_iinfo[MILAN_MAX_ISA_INTS];
66
67 void
68 isa_bus_init()
69 {
70 volatile u_int8_t *icu;
71
72 /*
73 * Initialize both the icu's:
74 * - enter Special Mask Mode
75 * - Block all interrupts
76 */
77 icu = (u_int8_t*)(AD_8259_MASTER);
78
79 icu[0] = 0x11; /* reset; program device, four bytes */
80 icu[1] = ICU_OFFSET; /* starting at this vector index */
81 icu[1] = (1 << IRQ_SLAVE); /* slave on line 2 */
82 icu[1] = 1; /* 8086 mode */
83 icu[1] = 0xff; /* leave interrupts masked */
84 icu[0] = 0x68; /* special mask mode */
85 icu[0] = 0x0a; /* Read IRR by default. */
86
87 icu = (u_int8_t*)(AD_8259_SLAVE);
88
89 icu[0] = 0x11; /* reset; program device, four bytes */
90 icu[1] = ICU_OFFSET + 8; /* starting at this vector index */
91 icu[1] = IRQ_SLAVE; /* slave on line 2 */
92 icu[1] = 1; /* 8086 mode */
93 icu[1] = 0xff; /* leave interrupts masked */
94 icu[0] = 0x68; /* special mask mode */
95 icu[0] = 0x0a; /* Read IRR by default. */
96 }
97
98 /*
99 * Determine and activate new interrupt mask by scanning the milan_isa_iinfo
100 * array for enabled interrupts.
101 */
102 static void
103 new_imask()
104 {
105 int irq;
106 u_int16_t nmask = 0;
107
108 for (irq = 0; irq < MILAN_MAX_ISA_INTS; irq++) {
109 if (milan_isa_iinfo[irq].ifunc != NULL)
110 nmask |= 1 << irq;
111 if (nmask >= 0x100)
112 nmask |= 1 << IRQ_SLAVE;
113 }
114 imask_enable = ~nmask;
115 WICU(AD_8259_MASTER+1, imask_enable & 0xff);
116 WICU(AD_8259_SLAVE+1 , (imask_enable >> 8) & 0xff);
117 }
118
119 static void
120 isa_callback(vector)
121 int vector;
122 {
123 isa_intr_info_t *iinfo_p;
124 int s;
125
126 iinfo_p = &milan_isa_iinfo[vector];
127
128 s = splx(iinfo_p->ipl);
129 (void) (iinfo_p->ifunc)(iinfo_p->iarg);
130 if (vector > 7)
131 WICU(AD_8259_SLAVE, 0x60 | (vector & 7));
132 else WICU(AD_8259_MASTER, 0x60 | (vector & 7));
133 splx(s);
134 }
135
136 void milan_isa_intr(int, int);
137 void
138 milan_isa_intr(vector, sr)
139 int vector, sr;
140 {
141 isa_intr_info_t *iinfo_p;
142 int s;
143
144 if (vector >= MILAN_MAX_ISA_INTS) {
145 printf("milan_isa_intr: Bogus vector %d\n", vector);
146 return;
147 }
148
149 /* Ack cascade 0x60 == Specific EOI */
150 if (vector > 7)
151 WICU(AD_8259_MASTER, 0x60|IRQ_SLAVE);
152
153 iinfo_p = &milan_isa_iinfo[vector];
154 if (iinfo_p->ifunc == NULL) {
155 printf("milan_isa_intr: Stray interrupt: %d (mask:%04x)\n",
156 vector, imask_enable);
157 return;
158 }
159 if ((sr & PSL_IPL) >= (iinfo_p->ipl & PSL_IPL)) {
160 /*
161 * We're running at a too high priority now.
162 */
163 add_sicallback((si_farg)isa_callback, (void*)vector, 0);
164 }
165 else {
166 s = splx(iinfo_p->ipl);
167 (void) (iinfo_p->ifunc)(iinfo_p->iarg);
168 if (vector > 7)
169 WICU(AD_8259_SLAVE, 0x60 | (vector & 7));
170 else WICU(AD_8259_MASTER, 0x60 | (vector & 7));
171 splx(s);
172 }
173 }
174
175 /*
176 * Try to allocate a free interrupt... On the Milan, we have available:
177 * 5, 9, 10, 11, 13. Or in a bitmask: 0x1720.
178 */
179 #define MILAN_AVAIL_ISA_INTS 0x1720
180
181 int
182 isa_intr_alloc(ic, mask, type, irq)
183 isa_chipset_tag_t ic;
184 int mask;
185 int type;
186 int *irq;
187 {
188 int i;
189
190 /*
191 * Say no to impossible questions...
192 */
193 if (!(mask &= MILAN_AVAIL_ISA_INTS))
194 return 1;
195
196 for (i = 0; i < MILAN_MAX_ISA_INTS; i++) {
197 if (mask & (1<<i)) {
198 if (milan_isa_iinfo[i].ifunc == NULL) {
199 *irq = i;
200 return 0;
201 }
202 }
203 }
204 return (1);
205 }
206
207 void *
208 isa_intr_establish(ic, irq, type, level, ih_fun, ih_arg)
209 isa_chipset_tag_t ic;
210 int irq, type, level;
211 int (*ih_fun) __P((void *));
212 void *ih_arg;
213 {
214 isa_intr_info_t *iinfo_p;
215
216 iinfo_p = &milan_isa_iinfo[irq];
217
218 if (iinfo_p->ifunc != NULL) {
219 printf("isa_intr_establish: interrupt %d was already "
220 "established\n", irq);
221 return NULL;
222 }
223
224 iinfo_p->slot = 0; /* Unused on Milan */
225 iinfo_p->ihand = NULL; /* Unused on Milan */
226 iinfo_p->ipl = level;
227 iinfo_p->ifunc = ih_fun;
228 iinfo_p->iarg = ih_arg;
229
230 new_imask();
231 return(iinfo_p);
232 }
233
234 void
235 isa_intr_disestablish(ic, handler)
236 isa_chipset_tag_t ic;
237 void *handler;
238 {
239 isa_intr_info_t *iinfo_p = (isa_intr_info_t *)handler;
240
241 if (iinfo_p->ifunc == NULL)
242 panic("isa_intr_disestablish: interrupt was not established\n");
243
244 iinfo_p->ifunc = NULL;
245 new_imask();
246 }
247