summaryrefslogtreecommitdiff
path: root/cpu/ixp/interrupts.c
blob: 2dd9561e1a57430be9a25468afb412a4a94fb6ed (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
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
/*
 * (C) Copyright 2006
 * Stefan Roese, DENX Software Engineering, sr@denx.de.
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Marius Groeger <mgroeger@sysgo.de>
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Alex Zuepke <azu@sysgo.de>
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

#include <common.h>
#include <asm/arch/ixp425.h>

#ifdef CONFIG_USE_IRQ
/*
 * When interrupts are enabled, use timer 2 for time/delay generation...
 */

#define FREQ		66666666
#define CLOCK_TICK_RATE	(((FREQ / CFG_HZ & ~IXP425_OST_RELOAD_MASK) + 1) * CFG_HZ)
#define LATCH		((CLOCK_TICK_RATE + CFG_HZ/2) / CFG_HZ)	/* For divider */

struct _irq_handler {
	void                *m_data;
	void (*m_func)( void *data);
};

static struct _irq_handler IRQ_HANDLER[N_IRQS];

static volatile ulong timestamp;

/* enable IRQ/FIQ interrupts */
void enable_interrupts(void)
{
	unsigned long temp;
	__asm__ __volatile__("mrs %0, cpsr\n"
			     "bic %0, %0, #0x80\n"
			     "msr cpsr_c, %0"
			     : "=r" (temp)
			     :
			     : "memory");
}

/*
 * disable IRQ/FIQ interrupts
 * returns true if interrupts had been enabled before we disabled them
 */
int disable_interrupts(void)
{
	unsigned long old,temp;
	__asm__ __volatile__("mrs %0, cpsr\n"
			     "orr %1, %0, #0x80\n"
			     "msr cpsr_c, %1"
			     : "=r" (old), "=r" (temp)
			     :
			     : "memory");
	return (old & 0x80) == 0;
}

static void default_isr(void *data)
{
	printf("default_isr():  called for IRQ %d, Interrupt Status=%x PR=%x\n",
	       (int)data, *IXP425_ICIP, *IXP425_ICIH);
}

static int next_irq(void)
{
	return (((*IXP425_ICIH & 0x000000fc) >> 2) - 1);
}

static void timer_isr(void *data)
{
	unsigned int *pTime = (unsigned int *)data;

	(*pTime)++;

	/*
	 * Reset IRQ source
	 */
	*IXP425_OSST = IXP425_OSST_TIMER_2_PEND;
}

ulong get_timer (ulong base)
{
	return timestamp - base;
}

void reset_timer (void)
{
	timestamp = 0;
}

#else /* #ifdef CONFIG_USE_IRQ */
void enable_interrupts (void)
{
	return;
}
int disable_interrupts (void)
{
	return 0;
}
#endif /* #ifdef CONFIG_USE_IRQ */

void bad_mode (void)
{
	panic ("Resetting CPU ...\n");
	reset_cpu (0);
}

void show_regs (struct pt_regs *regs)
{
	unsigned long flags;
	const char *processor_modes[] = {
	"USER_26",	"FIQ_26",	"IRQ_26",	"SVC_26",
	"UK4_26",	"UK5_26",	"UK6_26",	"UK7_26",
	"UK8_26",	"UK9_26",	"UK10_26",	"UK11_26",
	"UK12_26",	"UK13_26",	"UK14_26",	"UK15_26",
	"USER_32",	"FIQ_32",	"IRQ_32",	"SVC_32",
	"UK4_32",	"UK5_32",	"UK6_32",	"ABT_32",
	"UK8_32",	"UK9_32",	"UK10_32",	"UND_32",
	"UK12_32",	"UK13_32",	"UK14_32",	"SYS_32"
	};

	flags = condition_codes (regs);

	printf ("pc : [<%08lx>]    lr : [<%08lx>]\n"
		"sp : %08lx  ip : %08lx  fp : %08lx\n",
		instruction_pointer (regs),
		regs->ARM_lr, regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
	printf ("r10: %08lx  r9 : %08lx  r8 : %08lx\n",
		regs->ARM_r10, regs->ARM_r9, regs->ARM_r8);
	printf ("r7 : %08lx  r6 : %08lx  r5 : %08lx  r4 : %08lx\n",
		regs->ARM_r7, regs->ARM_r6, regs->ARM_r5, regs->ARM_r4);
	printf ("r3 : %08lx  r2 : %08lx  r1 : %08lx  r0 : %08lx\n",
		regs->ARM_r3, regs->ARM_r2, regs->ARM_r1, regs->ARM_r0);
	printf ("Flags: %c%c%c%c",
		flags & CC_N_BIT ? 'N' : 'n',
		flags & CC_Z_BIT ? 'Z' : 'z',
		flags & CC_C_BIT ? 'C' : 'c', flags & CC_V_BIT ? 'V' : 'v');
	printf ("  IRQs %s  FIQs %s  Mode %s%s\n",
		interrupts_enabled (regs) ? "on" : "off",
		fast_interrupts_enabled (regs) ? "on" : "off",
		processor_modes[processor_mode (regs)],
		thumb_mode (regs) ? " (T)" : "");
}

void do_undefined_instruction (struct pt_regs *pt_regs)
{
	printf ("undefined instruction\n");
	show_regs (pt_regs);
	bad_mode ();
}

void do_software_interrupt (struct pt_regs *pt_regs)
{
	printf ("software interrupt\n");
	show_regs (pt_regs);
	bad_mode ();
}

void do_prefetch_abort (struct pt_regs *pt_regs)
{
	printf ("prefetch abort\n");
	show_regs (pt_regs);
	bad_mode ();
}

void do_data_abort (struct pt_regs *pt_regs)
{
	printf ("data abort\n");
	show_regs (pt_regs);
	bad_mode ();
}

void do_not_used (struct pt_regs *pt_regs)
{
	printf ("not used\n");
	show_regs (pt_regs);
	bad_mode ();
}

void do_fiq (struct pt_regs *pt_regs)
{
	printf ("fast interrupt request\n");
	show_regs (pt_regs);
	printf("IRQ=%08lx FIQ=%08lx\n", *IXP425_ICIH, *IXP425_ICFH);
}

void do_irq (struct pt_regs *pt_regs)
{
#ifdef CONFIG_USE_IRQ
	int irq = next_irq();

	IRQ_HANDLER[irq].m_func(IRQ_HANDLER[irq].m_data);
#else
	printf ("interrupt request\n");
	show_regs (pt_regs);
	bad_mode ();
#endif
}

int interrupt_init (void)
{
#ifdef CONFIG_USE_IRQ
	int i;

	/* install default interrupt handlers */
	for (i = 0; i < N_IRQS; i++) {
		IRQ_HANDLER[i].m_data = (void *)i;
		IRQ_HANDLER[i].m_func = default_isr;
	}

	/* install interrupt handler for timer */
	IRQ_HANDLER[IXP425_TIMER_2_IRQ].m_data = (void *)&timestamp;
	IRQ_HANDLER[IXP425_TIMER_2_IRQ].m_func = timer_isr;

	/* setup the Timer counter value */
	*IXP425_OSRT2 = (LATCH & ~IXP425_OST_RELOAD_MASK) | IXP425_OST_ENABLE;

	/* configure interrupts for IRQ mode */
	*IXP425_ICLR = 0x00000000;

	/* enable timer irq */
	*IXP425_ICMR = (1 << IXP425_TIMER_2_IRQ);
#endif

	return (0);
}