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
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
|
/* $Id: irq.c,v 1.4 2005/01/04 12:22:28 starvik Exp $
*
* linux/arch/cris/kernel/irq.c
*
* Copyright (c) 2000-2002 Axis Communications AB
*
* Authors: Bjorn Wesen (bjornw@axis.com)
*
* This file contains the interrupt vectors and some
* helper functions
*
*/
#include <asm/irq.h>
#include <asm/current.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/init.h>
/* From kgdb.c. */
extern void kgdb_init(void);
extern void breakpoint(void);
#define mask_irq(irq_nr) (*R_VECT_MASK_CLR = 1 << (irq_nr));
#define unmask_irq(irq_nr) (*R_VECT_MASK_SET = 1 << (irq_nr));
/* don't use set_int_vector, it bypasses the linux interrupt handlers. it is
* global just so that the kernel gdb can use it.
*/
void
set_int_vector(int n, irqvectptr addr)
{
etrax_irv->v[n + 0x20] = (irqvectptr)addr;
}
/* the breakpoint vector is obviously not made just like the normal irq handlers
* but needs to contain _code_ to jump to addr.
*
* the BREAK n instruction jumps to IBR + n * 8
*/
void
set_break_vector(int n, irqvectptr addr)
{
unsigned short *jinstr = (unsigned short *)&etrax_irv->v[n*2];
unsigned long *jaddr = (unsigned long *)(jinstr + 1);
/* if you don't know what this does, do not touch it! */
*jinstr = 0x0d3f;
*jaddr = (unsigned long)addr;
/* 00000026 <clrlop+1a> 3f0d82000000 jump 0x82 */
}
/*
* This builds up the IRQ handler stubs using some ugly macros in irq.h
*
* These macros create the low-level assembly IRQ routines that do all
* the operations that are needed. They are also written to be fast - and to
* disable interrupts as little as humanly possible.
*
*/
/* IRQ0 and 1 are special traps */
void hwbreakpoint(void);
void IRQ1_interrupt(void);
BUILD_TIMER_IRQ(2, 0x04) /* the timer interrupt is somewhat special */
BUILD_IRQ(3, 0x08)
BUILD_IRQ(4, 0x10)
BUILD_IRQ(5, 0x20)
BUILD_IRQ(6, 0x40)
BUILD_IRQ(7, 0x80)
BUILD_IRQ(8, 0x100)
BUILD_IRQ(9, 0x200)
BUILD_IRQ(10, 0x400)
BUILD_IRQ(11, 0x800)
BUILD_IRQ(12, 0x1000)
BUILD_IRQ(13, 0x2000)
void mmu_bus_fault(void); /* IRQ 14 is the bus fault interrupt */
void multiple_interrupt(void); /* IRQ 15 is the multiple IRQ interrupt */
BUILD_IRQ(16, 0x10000 | 0x20000) /* ethernet tx interrupt needs to block rx */
BUILD_IRQ(17, 0x20000 | 0x10000) /* ...and vice versa */
BUILD_IRQ(18, 0x40000)
BUILD_IRQ(19, 0x80000)
BUILD_IRQ(20, 0x100000)
BUILD_IRQ(21, 0x200000)
BUILD_IRQ(22, 0x400000)
BUILD_IRQ(23, 0x800000)
BUILD_IRQ(24, 0x1000000)
BUILD_IRQ(25, 0x2000000)
/* IRQ 26-30 are reserved */
BUILD_IRQ(31, 0x80000000)
/*
* Pointers to the low-level handlers
*/
static void (*interrupt[NR_IRQS])(void) = {
NULL, NULL, IRQ2_interrupt, IRQ3_interrupt,
IRQ4_interrupt, IRQ5_interrupt, IRQ6_interrupt, IRQ7_interrupt,
IRQ8_interrupt, IRQ9_interrupt, IRQ10_interrupt, IRQ11_interrupt,
IRQ12_interrupt, IRQ13_interrupt, NULL, NULL,
IRQ16_interrupt, IRQ17_interrupt, IRQ18_interrupt, IRQ19_interrupt,
IRQ20_interrupt, IRQ21_interrupt, IRQ22_interrupt, IRQ23_interrupt,
IRQ24_interrupt, IRQ25_interrupt, NULL, NULL, NULL, NULL, NULL,
IRQ31_interrupt
};
static void enable_crisv10_irq(unsigned int irq);
static unsigned int startup_crisv10_irq(unsigned int irq)
{
enable_crisv10_irq(irq);
return 0;
}
#define shutdown_crisv10_irq disable_crisv10_irq
static void enable_crisv10_irq(unsigned int irq)
{
unmask_irq(irq);
}
static void disable_crisv10_irq(unsigned int irq)
{
mask_irq(irq);
}
static void ack_crisv10_irq(unsigned int irq)
{
}
static void end_crisv10_irq(unsigned int irq)
{
}
static struct hw_interrupt_type crisv10_irq_type = {
.typename = "CRISv10",
.startup = startup_crisv10_irq,
.shutdown = shutdown_crisv10_irq,
.enable = enable_crisv10_irq,
.disable = disable_crisv10_irq,
.ack = ack_crisv10_irq,
.end = end_crisv10_irq,
.set_affinity = NULL
};
void weird_irq(void);
void system_call(void); /* from entry.S */
void do_sigtrap(void); /* from entry.S */
void gdb_handle_breakpoint(void); /* from entry.S */
extern void do_IRQ(int irq, struct pt_regs * regs);
/* Handle multiple IRQs */
void do_multiple_IRQ(struct pt_regs* regs)
{
int bit;
unsigned masked;
unsigned mask;
unsigned ethmask = 0;
/* Get interrupts to mask and handle */
mask = masked = *R_VECT_MASK_RD;
/* Never mask timer IRQ */
mask &= ~(IO_MASK(R_VECT_MASK_RD, timer0));
/*
* If either ethernet interrupt (rx or tx) is active then block
* the other one too. Unblock afterwards also.
*/
if (mask &
(IO_STATE(R_VECT_MASK_RD, dma0, active) |
IO_STATE(R_VECT_MASK_RD, dma1, active))) {
ethmask = (IO_MASK(R_VECT_MASK_RD, dma0) |
IO_MASK(R_VECT_MASK_RD, dma1));
}
/* Block them */
*R_VECT_MASK_CLR = (mask | ethmask);
/* An extra irq_enter here to prevent softIRQs to run after
* each do_IRQ. This will decrease the interrupt latency.
*/
irq_enter();
/* Handle all IRQs */
for (bit = 2; bit < 32; bit++) {
if (masked & (1 << bit)) {
do_IRQ(bit, regs);
}
}
/* This irq_exit() will trigger the soft IRQs. */
irq_exit();
/* Unblock the IRQs again */
*R_VECT_MASK_SET = (masked | ethmask);
}
/* init_IRQ() is called by start_kernel and is responsible for fixing IRQ masks and
setting the irq vector table.
*/
void __init
init_IRQ(void)
{
int i;
/* clear all interrupt masks */
#ifndef CONFIG_SVINTO_SIM
*R_IRQ_MASK0_CLR = 0xffffffff;
*R_IRQ_MASK1_CLR = 0xffffffff;
*R_IRQ_MASK2_CLR = 0xffffffff;
#endif
*R_VECT_MASK_CLR = 0xffffffff;
for (i = 0; i < 256; i++)
etrax_irv->v[i] = weird_irq;
/* Initialize IRQ handler descriptors. */
for(i = 2; i < NR_IRQS; i++) {
irq_desc[i].chip = &crisv10_irq_type;
set_int_vector(i, interrupt[i]);
}
/* the entries in the break vector contain actual code to be
executed by the associated break handler, rather than just a jump
address. therefore we need to setup a default breakpoint handler
for all breakpoints */
for (i = 0; i < 16; i++)
set_break_vector(i, do_sigtrap);
/* except IRQ 15 which is the multiple-IRQ handler on Etrax100 */
set_int_vector(15, multiple_interrupt);
/* 0 and 1 which are special breakpoint/NMI traps */
set_int_vector(0, hwbreakpoint);
set_int_vector(1, IRQ1_interrupt);
/* and irq 14 which is the mmu bus fault handler */
set_int_vector(14, mmu_bus_fault);
/* setup the system-call trap, which is reached by BREAK 13 */
set_break_vector(13, system_call);
/* setup a breakpoint handler for debugging used for both user and
kernel mode debugging (which is why it is not inside an ifdef
CONFIG_ETRAX_KGDB) */
set_break_vector(8, gdb_handle_breakpoint);
#ifdef CONFIG_ETRAX_KGDB
/* setup kgdb if its enabled, and break into the debugger */
kgdb_init();
breakpoint();
#endif
}
|
