1 /*
2 * Toshiba RBTX4939 interrupt routines
3 * Based on linux/arch/mips/txx9/rbtx4938/irq.c,
4 * and RBTX49xx patch from CELF patch archive.
5 *
6 * Copyright (C) 2000-2001,2005-2006 Toshiba Corporation
7 * 2003-2005 (c) MontaVista Software, Inc. This file is licensed under the
8 * terms of the GNU General Public License version 2. This program is
9 * licensed "as is" without any warranty of any kind, whether express
10 * or implied.
11 */
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/irq.h>
15 #include <asm/mipsregs.h>
16 #include <asm/txx9/rbtx4939.h>
17
18 /*
19 * RBTX4939 IOC controller definition
20 */
21
rbtx4939_ioc_irq_unmask(struct irq_data * d)22 static void rbtx4939_ioc_irq_unmask(struct irq_data *d)
23 {
24 int ioc_nr = d->irq - RBTX4939_IRQ_IOC;
25
26 writeb(readb(rbtx4939_ien_addr) | (1 << ioc_nr), rbtx4939_ien_addr);
27 }
28
rbtx4939_ioc_irq_mask(struct irq_data * d)29 static void rbtx4939_ioc_irq_mask(struct irq_data *d)
30 {
31 int ioc_nr = d->irq - RBTX4939_IRQ_IOC;
32
33 writeb(readb(rbtx4939_ien_addr) & ~(1 << ioc_nr), rbtx4939_ien_addr);
34 mmiowb();
35 }
36
37 static struct irq_chip rbtx4939_ioc_irq_chip = {
38 .name = "IOC",
39 .irq_mask = rbtx4939_ioc_irq_mask,
40 .irq_unmask = rbtx4939_ioc_irq_unmask,
41 };
42
43
rbtx4939_ioc_irqroute(void)44 static inline int rbtx4939_ioc_irqroute(void)
45 {
46 unsigned char istat = readb(rbtx4939_ifac2_addr);
47
48 if (unlikely(istat == 0))
49 return -1;
50 return RBTX4939_IRQ_IOC + __fls8(istat);
51 }
52
rbtx4939_irq_dispatch(int pending)53 static int rbtx4939_irq_dispatch(int pending)
54 {
55 int irq;
56
57 if (pending & CAUSEF_IP7)
58 return MIPS_CPU_IRQ_BASE + 7;
59 irq = tx4939_irq();
60 if (likely(irq >= 0)) {
61 /* redirect IOC interrupts */
62 switch (irq) {
63 case RBTX4939_IRQ_IOCINT:
64 irq = rbtx4939_ioc_irqroute();
65 break;
66 }
67 } else if (pending & CAUSEF_IP0)
68 irq = MIPS_CPU_IRQ_BASE + 0;
69 else if (pending & CAUSEF_IP1)
70 irq = MIPS_CPU_IRQ_BASE + 1;
71 else
72 irq = -1;
73 return irq;
74 }
75
rbtx4939_irq_setup(void)76 void __init rbtx4939_irq_setup(void)
77 {
78 int i;
79
80 /* mask all IOC interrupts */
81 writeb(0, rbtx4939_ien_addr);
82
83 /* clear SoftInt interrupts */
84 writeb(0, rbtx4939_softint_addr);
85
86 txx9_irq_dispatch = rbtx4939_irq_dispatch;
87
88 tx4939_irq_init();
89 for (i = RBTX4939_IRQ_IOC;
90 i < RBTX4939_IRQ_IOC + RBTX4939_NR_IRQ_IOC; i++)
91 irq_set_chip_and_handler(i, &rbtx4939_ioc_irq_chip,
92 handle_level_irq);
93
94 irq_set_chained_handler(RBTX4939_IRQ_IOCINT, handle_simple_irq);
95 }
96