aboutsummaryrefslogtreecommitdiff
path: root/hw/etraxfs_pic.c
blob: 7022c99534210f6d5ec36a3eb6f003117bdb0c54 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
/*
 * QEMU ETRAX Interrupt Controller.
 *
 * Copyright (c) 2008 Edgar E. Iglesias, Axis Communications AB.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <stdio.h>
#include "hw.h"

#define D(x)

struct fs_pic_state_t
{
	CPUState *env;
	target_phys_addr_t base;

	uint32_t rw_mask;
	/* Active interrupt lines.  */
	uint32_t r_vect;
	/* Active lines, gated through the mask.  */
	uint32_t r_masked_vect;
	uint32_t r_nmi;
	uint32_t r_guru;
};

static uint32_t pic_readb (void *opaque, target_phys_addr_t addr)
{
	return 0;
}
static uint32_t pic_readw (void *opaque, target_phys_addr_t addr)
{
	return 0;
}

static uint32_t pic_readl (void *opaque, target_phys_addr_t addr)
{
	struct fs_pic_state_t *fs = opaque;
	uint32_t rval;

	/* Transform this to a relative addr.  */
	addr -= fs->base;
	switch (addr)
	{
		case 0x0: 
			rval = fs->rw_mask;
			break;
		case 0x4: 
			rval = fs->r_vect;
			break;
		case 0x8: 
			rval = fs->r_masked_vect;
			break;
		case 0xc: 
			rval = fs->r_nmi;
			break;
		case 0x10: 
			rval = fs->r_guru;
			break;
		default:
			cpu_abort(fs->env, "invalid PIC register.\n");
			break;

	}
	D(printf("%s %x=%x\n", __func__, addr, rval));
	return rval;
}

static void
pic_writeb (void *opaque, target_phys_addr_t addr, uint32_t value)
{
}

static void
pic_writew (void *opaque, target_phys_addr_t addr, uint32_t value)
{
}

static void
pic_writel (void *opaque, target_phys_addr_t addr, uint32_t value)
{
	struct fs_pic_state_t *fs = opaque;
	D(printf("%s addr=%x val=%x\n", __func__, addr, value));
	/* Transform this to a relative addr.  */
	addr -= fs->base;
	switch (addr) 
	{
		case 0x0: 
			fs->rw_mask = value;
			break;
		case 0x4: 
			fs->r_vect = value;
			break;
		case 0x8: 
			fs->r_masked_vect = value;
			break;
		case 0xc: 
			fs->r_nmi = value;
			break;
		case 0x10: 
			fs->r_guru = value;
			break;
		default:
			cpu_abort(fs->env, "invalid PIC register.\n");
			break;
	}
}

static CPUReadMemoryFunc *pic_read[] = {
	&pic_readb,
	&pic_readw,
	&pic_readl,
};

static CPUWriteMemoryFunc *pic_write[] = {
	&pic_writeb,
	&pic_writew,
	&pic_writel,
};

void pic_info(void)
{
}

void irq_info(void)
{
}

static void etraxfs_pic_handler(void *opaque, int irq, int level)
{	
	struct fs_pic_state_t *fs = (void *)opaque;
	CPUState *env = fs->env;
	int i;
	uint32_t vector = 0;

	D(printf("%s irq=%d level=%d mask=%x v=%x mv=%x\n", 
		 __func__, irq, level,
		 fs->rw_mask, fs->r_vect, fs->r_masked_vect));

	irq -= 1;
	fs->r_vect &= ~(1 << irq);
	fs->r_vect |= (!!level << irq);
	fs->r_masked_vect = fs->r_vect & fs->rw_mask;

	/* The ETRAX interrupt controller signals interrupts to teh core
	   through an interrupt request wire and an irq vector bus. If 
	   multiple interrupts are simultaneously active it chooses vector 
	   0x30 and lets the sw choose the priorities.  */
	if (fs->r_masked_vect) {
		uint32_t mv = fs->r_masked_vect;
		for (i = 0; i < 31; i++) {
			if (mv & 1) {
				vector = 0x31 + i;
				/* Check for multiple interrupts.  */
				if (mv > 1)
					vector = 0x30;
				break;
			}
			mv >>= 1;
		}
		if (vector) {
			env->interrupt_vector = vector;
			D(printf("%s vector=%x\n", __func__, vector));
			cpu_interrupt(env, CPU_INTERRUPT_HARD);
		}
	} else {
		env->interrupt_vector = 0;
		cpu_reset_interrupt(env, CPU_INTERRUPT_HARD);
		D(printf("%s reset irqs\n", __func__));
	}
}

qemu_irq *etraxfs_pic_init(CPUState *env, target_phys_addr_t base)
{
	struct fs_pic_state_t *fs;
	qemu_irq *pic;
	int intr_vect_regs;

	fs = qemu_mallocz(sizeof *fs);
	if (!fs)
		return NULL;
	fs->env = env;

	pic = qemu_allocate_irqs(etraxfs_pic_handler, fs, 30);

	intr_vect_regs = cpu_register_io_memory(0, pic_read, pic_write, fs);
	cpu_register_physical_memory(base, 0x14, intr_vect_regs);
	fs->base = base;

	return pic;
}