1 /*
2 * Copyright 2000 MontaVista Software Inc.
3 * Author: MontaVista Software, Inc.
4 * ppopov@mvista.com or source@mvista.com
5 *
6 * This file was derived from Carsten Langgaard's
7 * arch/mips/mips-boards/atlas/atlas_int.c.
8 *
9 * Carsten Langgaard, carstenl@mips.com
10 * Copyright (C) 1999,2000 MIPS Technologies, Inc. All rights reserved.
11 *
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms of the GNU General Public License as published by the
14 * Free Software Foundation; either version 2 of the License, or (at your
15 * option) any later version.
16 *
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
20 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
24 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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.
27 *
28 * You should have received a copy of the GNU General Public License along
29 * with this program; if not, write to the Free Software Foundation, Inc.,
30 * 675 Mass Ave, Cambridge, MA 02139, USA.
31 */
32 #include <linux/errno.h>
33 #include <linux/init.h>
34 #include <linux/kernel_stat.h>
35 #include <linux/irq.h>
36 #include <linux/module.h>
37 #include <linux/signal.h>
38 #include <linux/sched.h>
39 #include <linux/types.h>
40 #include <linux/interrupt.h>
41 #include <linux/ioport.h>
42 #include <linux/timex.h>
43 #include <linux/slab.h>
44 #include <linux/random.h>
45
46 #include <asm/bitops.h>
47 #include <asm/bootinfo.h>
48 #include <asm/io.h>
49 #include <asm/mipsregs.h>
50 #include <asm/system.h>
51 #include <asm/galileo-boards/ev96100int.h>
52
53 extern void mips_timer_interrupt(int irq, struct pt_regs *regs);
54 extern asmlinkage void ev96100IRQ(void);
55
disable_ev96100_irq(unsigned int irq_nr)56 static void disable_ev96100_irq(unsigned int irq_nr)
57 {
58 unsigned long flags;
59
60 save_and_cli(flags);
61 clear_c0_status(0x100 << irq_nr);
62 restore_flags(flags);
63 }
64
enable_ev96100_irq(unsigned int irq_nr)65 static inline void enable_ev96100_irq(unsigned int irq_nr)
66 {
67 unsigned long flags;
68
69 save_and_cli(flags);
70 set_c0_status(0x100 << irq_nr);
71 restore_flags(flags);
72 }
73
startup_ev96100_irq(unsigned int irq)74 static unsigned int startup_ev96100_irq(unsigned int irq)
75 {
76 enable_ev96100_irq(irq);
77
78 return 0; /* never anything pending */
79 }
80
81 #define shutdown_ev96100_irq disable_ev96100_irq
82 #define mask_and_ack_ev96100_irq disable_ev96100_irq
83
end_ev96100_irq(unsigned int irq)84 static void end_ev96100_irq (unsigned int irq)
85 {
86 if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
87 enable_ev96100_irq(irq);
88 }
89
ffz8(unsigned int word)90 static inline unsigned int ffz8(unsigned int word)
91 {
92 unsigned long k;
93
94 k = 7;
95 if (word & 0x0fUL) { k -= 4; word <<= 4; }
96 if (word & 0x30UL) { k -= 2; word <<= 2; }
97 if (word & 0x40UL) { k -= 1; }
98
99 return k;
100 }
101
ev96100_cpu_irq(unsigned long cause,struct pt_regs * regs)102 asmlinkage void ev96100_cpu_irq(unsigned long cause, struct pt_regs * regs)
103 {
104 if (!(cause & 0xff00))
105 return;
106
107 do_IRQ(ffz8((cause >> 8) & 0xff), regs);
108 }
109
110 static struct hw_interrupt_type ev96100_irq_type = {
111 "EV96100",
112 startup_ev96100_irq,
113 shutdown_ev96100_irq,
114 enable_ev96100_irq,
115 disable_ev96100_irq,
116 mask_and_ack_ev96100_irq,
117 end_ev96100_irq
118 };
119
init_IRQ(void)120 void __init init_IRQ(void)
121 {
122 int i;
123
124 set_except_vector(0, ev96100IRQ);
125 init_generic_irq();
126
127 for (i = 0; i < 8; i++) {
128 irq_desc[i].status = IRQ_DISABLED;
129 irq_desc[i].action = 0;
130 irq_desc[i].depth = 1;
131 irq_desc[i].handler = &ev96100_irq_type;
132 }
133 }
134