1 /*
2 * This program is free software; you can redistribute it and/or modify it
3 * under the terms of the GNU General Public License as published by the
4 * Free Software Foundation; either version 2 of the License, or (at your
5 * option) any later version.
6 *
7 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
8 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
9 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
10 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
11 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
12 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
13 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
14 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
15 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
16 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 675 Mass Ave, Cambridge, MA 02139, USA.
21 *
22 * Copyright 2002 MontaVista Software Inc.
23 * Author: MontaVista Software, Inc.
24 * stevel@mvista.com or source@mvista.com
25 */
26
27 #include <linux/bitops.h>
28 #include <linux/errno.h>
29 #include <linux/init.h>
30 #include <linux/io.h>
31 #include <linux/kernel_stat.h>
32 #include <linux/module.h>
33 #include <linux/signal.h>
34 #include <linux/sched.h>
35 #include <linux/types.h>
36 #include <linux/interrupt.h>
37 #include <linux/ioport.h>
38 #include <linux/timex.h>
39 #include <linux/random.h>
40 #include <linux/delay.h>
41
42 #include <asm/bootinfo.h>
43 #include <asm/time.h>
44 #include <asm/mipsregs.h>
45 #include <asm/system.h>
46
47 #include <asm/mach-rc32434/irq.h>
48 #include <asm/mach-rc32434/gpio.h>
49
50 struct intr_group {
51 u32 mask; /* mask of valid bits in pending/mask registers */
52 volatile u32 *base_addr;
53 };
54
55 #define RC32434_NR_IRQS (GROUP4_IRQ_BASE + 32)
56
57 #if (NR_IRQS < RC32434_NR_IRQS)
58 #error Too little irqs defined. Did you override <asm/irq.h> ?
59 #endif
60
61 static const struct intr_group intr_group[NUM_INTR_GROUPS] = {
62 {
63 .mask = 0x0000efff,
64 .base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 0 * IC_GROUP_OFFSET)},
65 {
66 .mask = 0x00001fff,
67 .base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 1 * IC_GROUP_OFFSET)},
68 {
69 .mask = 0x00000007,
70 .base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 2 * IC_GROUP_OFFSET)},
71 {
72 .mask = 0x0003ffff,
73 .base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 3 * IC_GROUP_OFFSET)},
74 {
75 .mask = 0xffffffff,
76 .base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 4 * IC_GROUP_OFFSET)}
77 };
78
79 #define READ_PEND(base) (*(base))
80 #define READ_MASK(base) (*(base + 2))
81 #define WRITE_MASK(base, val) (*(base + 2) = (val))
82
irq_to_group(unsigned int irq_nr)83 static inline int irq_to_group(unsigned int irq_nr)
84 {
85 return (irq_nr - GROUP0_IRQ_BASE) >> 5;
86 }
87
group_to_ip(unsigned int group)88 static inline int group_to_ip(unsigned int group)
89 {
90 return group + 2;
91 }
92
enable_local_irq(unsigned int ip)93 static inline void enable_local_irq(unsigned int ip)
94 {
95 int ipnum = 0x100 << ip;
96
97 set_c0_status(ipnum);
98 }
99
disable_local_irq(unsigned int ip)100 static inline void disable_local_irq(unsigned int ip)
101 {
102 int ipnum = 0x100 << ip;
103
104 clear_c0_status(ipnum);
105 }
106
ack_local_irq(unsigned int ip)107 static inline void ack_local_irq(unsigned int ip)
108 {
109 int ipnum = 0x100 << ip;
110
111 clear_c0_cause(ipnum);
112 }
113
rb532_enable_irq(struct irq_data * d)114 static void rb532_enable_irq(struct irq_data *d)
115 {
116 unsigned int group, intr_bit, irq_nr = d->irq;
117 int ip = irq_nr - GROUP0_IRQ_BASE;
118 volatile unsigned int *addr;
119
120 if (ip < 0)
121 enable_local_irq(irq_nr);
122 else {
123 group = ip >> 5;
124
125 ip &= (1 << 5) - 1;
126 intr_bit = 1 << ip;
127
128 enable_local_irq(group_to_ip(group));
129
130 addr = intr_group[group].base_addr;
131 WRITE_MASK(addr, READ_MASK(addr) & ~intr_bit);
132 }
133 }
134
rb532_disable_irq(struct irq_data * d)135 static void rb532_disable_irq(struct irq_data *d)
136 {
137 unsigned int group, intr_bit, mask, irq_nr = d->irq;
138 int ip = irq_nr - GROUP0_IRQ_BASE;
139 volatile unsigned int *addr;
140
141 if (ip < 0) {
142 disable_local_irq(irq_nr);
143 } else {
144 group = ip >> 5;
145
146 ip &= (1 << 5) - 1;
147 intr_bit = 1 << ip;
148 addr = intr_group[group].base_addr;
149 mask = READ_MASK(addr);
150 mask |= intr_bit;
151 WRITE_MASK(addr, mask);
152
153 /* There is a maximum of 14 GPIO interrupts */
154 if (group == GPIO_MAPPED_IRQ_GROUP && irq_nr <= (GROUP4_IRQ_BASE + 13))
155 rb532_gpio_set_istat(0, irq_nr - GPIO_MAPPED_IRQ_BASE);
156
157 /*
158 * if there are no more interrupts enabled in this
159 * group, disable corresponding IP
160 */
161 if (mask == intr_group[group].mask)
162 disable_local_irq(group_to_ip(group));
163 }
164 }
165
rb532_mask_and_ack_irq(struct irq_data * d)166 static void rb532_mask_and_ack_irq(struct irq_data *d)
167 {
168 rb532_disable_irq(d);
169 ack_local_irq(group_to_ip(irq_to_group(d->irq)));
170 }
171
rb532_set_type(struct irq_data * d,unsigned type)172 static int rb532_set_type(struct irq_data *d, unsigned type)
173 {
174 int gpio = d->irq - GPIO_MAPPED_IRQ_BASE;
175 int group = irq_to_group(d->irq);
176
177 if (group != GPIO_MAPPED_IRQ_GROUP || d->irq > (GROUP4_IRQ_BASE + 13))
178 return (type == IRQ_TYPE_LEVEL_HIGH) ? 0 : -EINVAL;
179
180 switch (type) {
181 case IRQ_TYPE_LEVEL_HIGH:
182 rb532_gpio_set_ilevel(1, gpio);
183 break;
184 case IRQ_TYPE_LEVEL_LOW:
185 rb532_gpio_set_ilevel(0, gpio);
186 break;
187 default:
188 return -EINVAL;
189 }
190
191 return 0;
192 }
193
194 static struct irq_chip rc32434_irq_type = {
195 .name = "RB532",
196 .irq_ack = rb532_disable_irq,
197 .irq_mask = rb532_disable_irq,
198 .irq_mask_ack = rb532_mask_and_ack_irq,
199 .irq_unmask = rb532_enable_irq,
200 .irq_set_type = rb532_set_type,
201 };
202
arch_init_irq(void)203 void __init arch_init_irq(void)
204 {
205 int i;
206
207 pr_info("Initializing IRQ's: %d out of %d\n", RC32434_NR_IRQS, NR_IRQS);
208
209 for (i = 0; i < RC32434_NR_IRQS; i++)
210 irq_set_chip_and_handler(i, &rc32434_irq_type,
211 handle_level_irq);
212 }
213
214 /* Main Interrupt dispatcher */
plat_irq_dispatch(void)215 asmlinkage void plat_irq_dispatch(void)
216 {
217 unsigned int ip, pend, group;
218 volatile unsigned int *addr;
219 unsigned int cp0_cause = read_c0_cause() & read_c0_status();
220
221 if (cp0_cause & CAUSEF_IP7) {
222 do_IRQ(7);
223 } else {
224 ip = (cp0_cause & 0x7c00);
225 if (ip) {
226 group = 21 + (fls(ip) - 32);
227
228 addr = intr_group[group].base_addr;
229
230 pend = READ_PEND(addr);
231 pend &= ~READ_MASK(addr); /* only unmasked interrupts */
232 pend = 39 + (fls(pend) - 32);
233 do_IRQ((group << 5) + pend);
234 }
235 }
236 }
237