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1
/*
1
/*
2
 * Copyright (c) 2007 Michal Kebrt, Petr Stepan
2
 * Copyright (c) 2007 Michal Kebrt, Petr Stepan
3
 * All rights reserved.
3
 * All rights reserved.
4
 *
4
 *
5
 * Redistribution and use in source and binary forms, with or without
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
6
 * modification, are permitted provided that the following conditions
7
 * are met:
7
 * are met:
8
 *
8
 *
9
 * - Redistributions of source code must retain the above copyright
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
15
 *   derived from this software without specific prior written permission.
16
 *
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
27
 */
28
 
28
 
29
/** @addtogroup arm32
29
/** @addtogroup arm32
30
 * @{
30
 * @{
31
 */
31
 */
32
/** @file
32
/** @file
33
 */
33
 */
34
 
34
 
35
#include <interrupt.h>
35
#include <interrupt.h>
36
#include <ipc/irq.h>
36
#include <ipc/irq.h>
37
#include <console/chardev.h>
37
#include <console/chardev.h>
38
#include <arch/drivers/gxemul.h>
38
#include <arch/drivers/gxemul.h>
39
#include <console/console.h>
39
#include <console/console.h>
40
#include <sysinfo/sysinfo.h>
40
#include <sysinfo/sysinfo.h>
41
#include <print.h>
41
#include <print.h>
42
#include <ddi/device.h>
42
#include <ddi/device.h>
43
#include <mm/page.h>
43
#include <mm/page.h>
44
#include <arch/machine.h>
44
#include <arch/machine.h>
45
 
45
 
46
/** Address of devices. */
46
/** Address of devices. */
47
#define GXEMUL_VIDEORAM            0x10000000
47
#define GXEMUL_VIDEORAM            0x10000000
48
#define GXEMUL_KBD                 0x10000000
48
#define GXEMUL_KBD                 0x10000000
49
#define GXEMUL_RTC                 0x15000000
49
#define GXEMUL_RTC                 0x15000000
50
#define GXEMUL_RTC_FREQ_OFFSET     0x100
50
#define GXEMUL_RTC_FREQ_OFFSET     0x100
51
#define GXEMUL_RTC_ACK_OFFSET      0x110
51
#define GXEMUL_RTC_ACK_OFFSET      0x110
52
#define GXEMUL_IRQC                0x16000000
52
#define GXEMUL_IRQC                0x16000000
53
#define GXEMUL_IRQC_MASK_OFFSET    0x4
53
#define GXEMUL_IRQC_MASK_OFFSET    0x4
54
#define GXEMUL_IRQC_UNMASK_OFFSET  0x8
54
#define GXEMUL_IRQC_UNMASK_OFFSET  0x8
55
#define GXEMUL_MP                  0x11000000
55
#define GXEMUL_MP                  0x11000000
56
#define GXEMUL_MP_MEMSIZE_OFFSET   0x0090
56
#define GXEMUL_MP_MEMSIZE_OFFSET   0x0090
57
 
57
 
58
 
58
 
59
/** IRQs */
59
/** IRQs */
60
#define GXEMUL_KBD_IRQ      2
60
#define GXEMUL_KBD_IRQ      2
61
#define GXEMUL_TIMER_IRQ    4
61
#define GXEMUL_TIMER_IRQ    4
62
 
62
 
63
static gxemul_hw_map_t gxemul_hw_map;
63
static gxemul_hw_map_t gxemul_hw_map;
64
static chardev_t console;
64
static chardev_t console;
65
static irq_t gxemul_irq;
65
static irq_t gxemul_irq;
66
static irq_t gxemul_timer_irq;
66
static irq_t gxemul_timer_irq;
67
 
67
 
-
 
68
static bool hw_map_init_called = false;
-
 
69
 
68
static void gxemul_write(chardev_t *dev, const char ch);
70
static void gxemul_write(chardev_t *dev, const char ch);
69
static void gxemul_enable(chardev_t *dev);
71
static void gxemul_enable(chardev_t *dev);
70
static void gxemul_disable(chardev_t *dev);
72
static void gxemul_disable(chardev_t *dev);
71
static char gxemul_do_read(chardev_t *dev);
73
static char gxemul_do_read(chardev_t *dev);
72
 
74
 
73
static chardev_operations_t gxemul_ops = {
75
static chardev_operations_t gxemul_ops = {
74
    .resume = gxemul_enable,
76
    .resume = gxemul_enable,
75
    .suspend = gxemul_disable,
77
    .suspend = gxemul_disable,
76
    .write = gxemul_write,
78
    .write = gxemul_write,
77
    .read = gxemul_do_read,
79
    .read = gxemul_do_read,
78
};
80
};
79
 
81
 
80
 
82
 
81
/** Initializes #gxemul_hw_map. */
83
/** Initializes #gxemul_hw_map. */
82
void gxemul_hw_map_init(void)
84
void gxemul_hw_map_init(void)
83
{
85
{
84
    gxemul_hw_map.videoram = hw_map(GXEMUL_VIDEORAM, PAGE_SIZE);
86
    gxemul_hw_map.videoram = hw_map(GXEMUL_VIDEORAM, PAGE_SIZE);
85
    gxemul_hw_map.kbd = hw_map(GXEMUL_KBD, PAGE_SIZE);
87
    gxemul_hw_map.kbd = hw_map(GXEMUL_KBD, PAGE_SIZE);
86
    gxemul_hw_map.rtc = hw_map(GXEMUL_RTC, PAGE_SIZE);
88
    gxemul_hw_map.rtc = hw_map(GXEMUL_RTC, PAGE_SIZE);
87
    gxemul_hw_map.irqc = hw_map(GXEMUL_IRQC, PAGE_SIZE);
89
    gxemul_hw_map.irqc = hw_map(GXEMUL_IRQC, PAGE_SIZE);
88
 
90
 
89
    gxemul_hw_map.rtc_freq = gxemul_hw_map.rtc + GXEMUL_RTC_FREQ_OFFSET;
91
    gxemul_hw_map.rtc_freq = gxemul_hw_map.rtc + GXEMUL_RTC_FREQ_OFFSET;
90
    gxemul_hw_map.rtc_ack = gxemul_hw_map.rtc + GXEMUL_RTC_ACK_OFFSET;
92
    gxemul_hw_map.rtc_ack = gxemul_hw_map.rtc + GXEMUL_RTC_ACK_OFFSET;
91
    gxemul_hw_map.irqc_mask = gxemul_hw_map.irqc + GXEMUL_IRQC_MASK_OFFSET;
93
    gxemul_hw_map.irqc_mask = gxemul_hw_map.irqc + GXEMUL_IRQC_MASK_OFFSET;
92
    gxemul_hw_map.irqc_unmask = gxemul_hw_map.irqc + GXEMUL_IRQC_UNMASK_OFFSET;
94
    gxemul_hw_map.irqc_unmask = gxemul_hw_map.irqc + GXEMUL_IRQC_UNMASK_OFFSET;
93
 
95
 
-
 
96
    hw_map_init_called = true;
94
}
97
}
95
 
98
 
96
/** Putchar that works with gxemul */
99
/** Putchar that works with gxemul */
97
void gxemul_write(chardev_t *dev, const char ch)
100
void gxemul_write(chardev_t *dev, const char ch)
98
{
101
{
99
    *((char *) gxemul_hw_map.videoram) = ch;
102
    *((char *) gxemul_hw_map.videoram) = ch;
100
}
103
}
101
 
104
 
102
/* Called from getc(). */
105
/* Called from getc(). */
103
void gxemul_enable(chardev_t *dev)
106
void gxemul_enable(chardev_t *dev)
104
{
107
{
105
//  cp0_unmask_int(GXEMUL_KBD_IRQ);
108
//  cp0_unmask_int(GXEMUL_KBD_IRQ);
106
    gxemul_irqc_unmask(GXEMUL_KBD_IRQ);
109
    gxemul_irqc_unmask(GXEMUL_KBD_IRQ);
107
}
110
}
108
 
111
 
109
/* Called from getc(). */
112
/* Called from getc(). */
110
void gxemul_disable(chardev_t *dev)
113
void gxemul_disable(chardev_t *dev)
111
{
114
{
112
//  cp0_mask_int(GXEMUL_KBD_IRQ);
115
//  cp0_mask_int(GXEMUL_KBD_IRQ);
113
    gxemul_irqc_mask(GXEMUL_KBD_IRQ);
116
    gxemul_irqc_mask(GXEMUL_KBD_IRQ);
114
}
117
}
115
 
118
 
116
/** Read character using polling, assume interrupts disabled */
119
/** Read character using polling, assume interrupts disabled */
117
static char gxemul_do_read(chardev_t *dev)
120
static char gxemul_do_read(chardev_t *dev)
118
{
121
{
119
    char ch;
122
    char ch;
120
 
123
 
121
    while (1) {
124
    while (1) {
122
        ch = *((volatile char *) gxemul_hw_map.kbd);
125
        ch = *((volatile char *) gxemul_hw_map.kbd);
123
        if (ch) {
126
        if (ch) {
124
            if (ch == '\r')
127
            if (ch == '\r')
125
                return '\n';
128
                return '\n';
126
            if (ch == 0x7f)
129
            if (ch == 0x7f)
127
                return '\b';
130
                return '\b';
128
            return ch;
131
            return ch;
129
        }
132
        }
130
    }
133
    }
131
}
134
}
132
 
135
 
133
/** Process keyboard interrupt. */
136
/** Process keyboard interrupt. */
134
static void gxemul_irq_handler(irq_t *irq, void *arg, ...)
137
static void gxemul_irq_handler(irq_t *irq, void *arg, ...)
135
{
138
{
136
    if ((irq->notif_cfg.notify) && (irq->notif_cfg.answerbox))
139
    if ((irq->notif_cfg.notify) && (irq->notif_cfg.answerbox))
137
        ipc_irq_send_notif(irq);
140
        ipc_irq_send_notif(irq);
138
    else {
141
    else {
139
        char ch = 0;
142
        char ch = 0;
140
       
143
       
141
            ch = *((char *) gxemul_hw_map.kbd);
144
            ch = *((char *) gxemul_hw_map.kbd);
142
            if (ch =='\r')
145
            if (ch =='\r')
143
                ch = '\n';
146
                ch = '\n';
144
            if (ch == 0x7f)
147
            if (ch == 0x7f)
145
                ch = '\b';
148
                ch = '\b';
146
            chardev_push_character(&console, ch);
149
            chardev_push_character(&console, ch);
147
    }
150
    }
148
}
151
}
149
 
152
 
150
static irq_ownership_t gxemul_claim(void)
153
static irq_ownership_t gxemul_claim(void)
151
{
154
{
152
    return IRQ_ACCEPT;
155
    return IRQ_ACCEPT;
153
}
156
}
154
 
157
 
155
void machine_grab_console(void)
158
void machine_grab_console(void)
156
{
159
{
157
    ipl_t ipl = interrupts_disable();
160
    ipl_t ipl = interrupts_disable();
158
    spinlock_lock(&gxemul_irq.lock);
161
    spinlock_lock(&gxemul_irq.lock);
159
    gxemul_irq.notif_cfg.notify = false;
162
    gxemul_irq.notif_cfg.notify = false;
160
    spinlock_unlock(&gxemul_irq.lock);
163
    spinlock_unlock(&gxemul_irq.lock);
161
    interrupts_restore(ipl);
164
    interrupts_restore(ipl);
162
}
165
}
163
 
166
 
164
void machine_release_console(void)
167
void machine_release_console(void)
165
{
168
{
166
    ipl_t ipl = interrupts_disable();
169
    ipl_t ipl = interrupts_disable();
167
    spinlock_lock(&gxemul_irq.lock);
170
    spinlock_lock(&gxemul_irq.lock);
168
    if (gxemul_irq.notif_cfg.answerbox)
171
    if (gxemul_irq.notif_cfg.answerbox)
169
        gxemul_irq.notif_cfg.notify = true;
172
        gxemul_irq.notif_cfg.notify = true;
170
    spinlock_unlock(&gxemul_irq.lock);
173
    spinlock_unlock(&gxemul_irq.lock);
171
    interrupts_restore(ipl);
174
    interrupts_restore(ipl);
172
}
175
}
173
 
176
 
174
 
177
 
175
/** Return console object representing gxemul console */
178
/** Return console object representing gxemul console */
176
void machine_console_init(devno_t devno)
179
void machine_console_init(devno_t devno)
177
{
180
{
178
    chardev_initialize("gxemul_console", &console, &gxemul_ops);
181
    chardev_initialize("gxemul_console", &console, &gxemul_ops);
179
    stdin = &console;
182
    stdin = &console;
180
    stdout = &console;
183
    stdout = &console;
181
   
184
   
182
    irq_initialize(&gxemul_irq);
185
    irq_initialize(&gxemul_irq);
183
    gxemul_irq.devno = devno;
186
    gxemul_irq.devno = devno;
184
    gxemul_irq.inr = GXEMUL_KBD_IRQ;
187
    gxemul_irq.inr = GXEMUL_KBD_IRQ;
185
    gxemul_irq.claim = gxemul_claim;
188
    gxemul_irq.claim = gxemul_claim;
186
    gxemul_irq.handler = gxemul_irq_handler;
189
    gxemul_irq.handler = gxemul_irq_handler;
187
    irq_register(&gxemul_irq);
190
    irq_register(&gxemul_irq);
188
   
191
   
189
//  cp0_unmask_int(GXEMUL_KBD_IRQ);
192
//  cp0_unmask_int(GXEMUL_KBD_IRQ);
190
    gxemul_irqc_unmask(GXEMUL_KBD_IRQ);
193
    gxemul_irqc_unmask(GXEMUL_KBD_IRQ);
191
   
194
   
192
    sysinfo_set_item_val("kbd", NULL, true);
195
    sysinfo_set_item_val("kbd", NULL, true);
193
    sysinfo_set_item_val("kbd.devno", NULL, devno);
196
    sysinfo_set_item_val("kbd.devno", NULL, devno);
194
    sysinfo_set_item_val("kbd.inr", NULL, GXEMUL_KBD_IRQ);
197
    sysinfo_set_item_val("kbd.inr", NULL, GXEMUL_KBD_IRQ);
195
    sysinfo_set_item_val("kbd.address.virtual", NULL, gxemul_hw_map.kbd);
198
    sysinfo_set_item_val("kbd.address.virtual", NULL, gxemul_hw_map.kbd);
196
}
199
}
197
 
200
 
198
/** Return the mask of active interrupts. */
201
/** Return the mask of active interrupts. */
199
inline uint32_t gxemul_irqc_get_sources(void)
202
inline uint32_t gxemul_irqc_get_sources(void)
200
{
203
{
201
    return *(uint32_t*) gxemul_hw_map.irqc;
204
    return *(uint32_t*) gxemul_hw_map.irqc;
202
}
205
}
203
 
206
 
204
/** Masks interrupt.
207
/** Masks interrupt.
205
 *
208
 *
206
 * @param irq interrupt number
209
 * @param irq interrupt number
207
 */
210
 */
208
inline void gxemul_irqc_mask(uint32_t irq)
211
inline void gxemul_irqc_mask(uint32_t irq)
209
{
212
{
210
    *(uint32_t*) gxemul_hw_map.irqc_mask = irq;
213
    *(uint32_t*) gxemul_hw_map.irqc_mask = irq;
211
}
214
}
212
 
215
 
213
/** Unmasks interrupt.
216
/** Unmasks interrupt.
214
 *
217
 *
215
 * @param irq interrupt number
218
 * @param irq interrupt number
216
 */
219
 */
217
inline void gxemul_irqc_unmask(uint32_t irq)
220
inline void gxemul_irqc_unmask(uint32_t irq)
218
{
221
{
219
    *(uint32_t*) gxemul_hw_map.irqc_unmask = irq;
222
    *(uint32_t*) gxemul_hw_map.irqc_unmask = irq;
220
}
223
}
221
 
224
 
222
 
225
 
223
/** Starts gxemul Real Time Clock device, which asserts regular interrupts.
226
/** Starts gxemul Real Time Clock device, which asserts regular interrupts.
224
 *
227
 *
225
 * @param frequency interrupts frequency (0 disables RTC)
228
 * @param frequency interrupts frequency (0 disables RTC)
226
 */
229
 */
227
void gxemul_timer_start(uint32_t frequency)
230
void gxemul_timer_start(uint32_t frequency)
228
{
231
{
229
    *(uint32_t*) gxemul_hw_map.rtc_freq = frequency;
232
    *(uint32_t*) gxemul_hw_map.rtc_freq = frequency;
230
}
233
}
231
 
234
 
232
static irq_ownership_t gxemul_timer_claim(void)
235
static irq_ownership_t gxemul_timer_claim(void)
233
{
236
{
234
    return IRQ_ACCEPT;
237
    return IRQ_ACCEPT;
235
}
238
}
236
 
239
 
237
static void gxemul_timer_irq_handler(irq_t *irq, void *arg, ...)
240
static void gxemul_timer_irq_handler(irq_t *irq, void *arg, ...)
238
{
241
{
239
    /* TODO time drifts ??
242
    /* TODO time drifts ??
240
    unsigned long drift;
243
    unsigned long drift;
241
 
244
 
242
    drift = cp0_count_read() - nextcount;
245
    drift = cp0_count_read() - nextcount;
243
    while (drift > cp0_compare_value) {
246
    while (drift > cp0_compare_value) {
244
        drift -= cp0_compare_value;
247
        drift -= cp0_compare_value;
245
        CPU->missed_clock_ticks++;
248
        CPU->missed_clock_ticks++;
246
    }
249
    }
247
    nextcount = cp0_count_read() + cp0_compare_value - drift;
250
    nextcount = cp0_count_read() + cp0_compare_value - drift;
248
    cp0_compare_write(nextcount);
251
    cp0_compare_write(nextcount);
249
    */
252
    */
250
 
253
 
251
    /*
254
    /*
252
    * We are holding a lock which prevents preemption.
255
    * We are holding a lock which prevents preemption.
253
    * Release the lock, call clock() and reacquire the lock again.
256
    * Release the lock, call clock() and reacquire the lock again.
254
    */
257
    */
255
    spinlock_unlock(&irq->lock);
258
    spinlock_unlock(&irq->lock);
256
    clock();
259
    clock();
257
    spinlock_lock(&irq->lock);
260
    spinlock_lock(&irq->lock);
258
 
261
 
259
    /* acknowledge tick */
262
    /* acknowledge tick */
260
    *(uint32_t*) gxemul_hw_map.rtc_ack = 0;
263
    *(uint32_t*) gxemul_hw_map.rtc_ack = 0;
261
   
264
   
262
    /* TODO what's that? *
265
    /* TODO what's that? *
263
    if (virtual_timer_fnc != NULL)
266
    if (virtual_timer_fnc != NULL)
264
        virtual_timer_fnc();
267
        virtual_timer_fnc();
265
    */
268
    */
266
}
269
}
267
 
270
 
268
/**
271
/**
269
 * Initializes and registers timer interrupt handler.
272
 * Initializes and registers timer interrupt handler.
270
 */
273
 */
271
void gxemul_timer_irq_init()
274
void gxemul_timer_irq_init()
272
{
275
{
273
    irq_initialize(&gxemul_timer_irq);
276
    irq_initialize(&gxemul_timer_irq);
274
    gxemul_timer_irq.devno = device_assign_devno();
277
    gxemul_timer_irq.devno = device_assign_devno();
275
    gxemul_timer_irq.inr = GXEMUL_TIMER_IRQ;
278
    gxemul_timer_irq.inr = GXEMUL_TIMER_IRQ;
276
    gxemul_timer_irq.claim = gxemul_timer_claim;
279
    gxemul_timer_irq.claim = gxemul_timer_claim;
277
    gxemul_timer_irq.handler = gxemul_timer_irq_handler;
280
    gxemul_timer_irq.handler = gxemul_timer_irq_handler;
278
 
281
 
279
    irq_register(&gxemul_timer_irq);
282
    irq_register(&gxemul_timer_irq);
280
}
283
}
281
 
284
 
282
void machine_timer_irq_start()
285
void machine_timer_irq_start()
283
{
286
{
284
    gxemul_timer_irq_init();
287
    gxemul_timer_irq_init();
285
    gxemul_timer_start(GXEMUL_TIMER_FREQ);
288
    gxemul_timer_start(GXEMUL_TIMER_FREQ);
286
}
289
}
287
 
290
 
288
size_t machine_get_memory_size(void)
291
size_t machine_get_memory_size(void)
289
{
292
{
290
    return  *((int*)(GXEMUL_MP + GXEMUL_MP_MEMSIZE_OFFSET));
293
    return  *((int*)(GXEMUL_MP + GXEMUL_MP_MEMSIZE_OFFSET));
291
}
294
}
292
 
295
 
293
void gxemul_debug_putc(char ch) {
296
void machine_debug_putc(char ch) {
-
 
297
    if (!hw_map_init_called) {
294
//  *((volatile char *) GXEMUL_KBD) = ch;
298
        *((volatile char *) GXEMUL_KBD) = ch;
295
//TODO commented version doesn't work, don't know why (as ??
299
    } else {
296
    *((char *) gxemul_hw_map.videoram) = ch;
300
        *((char *) gxemul_hw_map.videoram) = ch;
-
 
301
    }
297
}
302
}
298
 
303
 
299
/** @}
304
/** @}
300
 */
305
 */
301
 
306