rewrite of platform irq handler
[openwrt.git] / target / linux / aruba-2.6 / patches / 002-irq.patch
1 diff -Nur linux-2.6.17/arch/mips/aruba/irq.c linux-2.6.17-openwrt/arch/mips/aruba/irq.c
2 --- linux-2.6.17/arch/mips/aruba/irq.c  1970-01-01 01:00:00.000000000 +0100
3 +++ linux-2.6.17-openwrt/arch/mips/aruba/irq.c  2006-10-12 14:32:40.026285000 -0700
4 @@ -0,0 +1,282 @@
5 +#include <linux/errno.h>
6 +#include <linux/init.h>
7 +#include <linux/kernel_stat.h>
8 +#include <linux/module.h>
9 +#include <linux/signal.h>
10 +#include <linux/sched.h>
11 +#include <linux/types.h>
12 +#include <linux/interrupt.h>
13 +#include <linux/ioport.h>
14 +#include <linux/timex.h>
15 +#include <linux/slab.h>
16 +#include <linux/random.h>
17 +#include <linux/delay.h>
18 +
19 +#include <asm/bitops.h>
20 +#include <asm/bootinfo.h>
21 +#include <asm/io.h>
22 +#include <asm/mipsregs.h>
23 +#include <asm/system.h>
24 +#include <asm/idt-boards/rc32434/rc32434.h>
25 +#include <asm/idt-boards/rc32434/rc32434_gpio.h>
26 +
27 +#include <asm/irq.h>
28 +
29 +extern void aruba_timer_interrupt(struct pt_regs *regs);
30 +
31 +typedef struct {
32 +       u32 mask;
33 +       volatile u32 *base_addr;
34 +} intr_group_t;
35 +
36 +static const intr_group_t intr_group_merlot[NUM_INTR_GROUPS] = {
37 +       {0x00000000, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 0)},
38 +};
39 +
40 +#define READ_PEND_MERLOT(base) (*((volatile unsigned long *)(0xbc003010)))
41 +#define READ_MASK_MERLOT(base) (*((volatile unsigned long *)(0xbc003014)))
42 +#define WRITE_MASK_MERLOT(base, val) ((*((volatile unsigned long *)(0xbc003014))) = (val), READ_MASK_MERLOT())
43 +
44 +static const intr_group_t intr_group_muscat[NUM_INTR_GROUPS] = {
45 +       {0x0000efff, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 0 * IC_GROUP_OFFSET)},
46 +       {0x00001fff, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 1 * IC_GROUP_OFFSET)},
47 +       {0x00000007, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 2 * IC_GROUP_OFFSET)},
48 +       {0x0003ffff, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 3 * IC_GROUP_OFFSET)},
49 +       {0xffffffff, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 4 * IC_GROUP_OFFSET)}
50 +};
51 +
52 +#define READ_PEND_MUSCAT(base) (*(base))
53 +#define READ_MASK_MUSCAT(base) (*(base + 2))
54 +#define WRITE_MASK_MUSCAT(base, val) (*(base + 2) = (val))
55 +
56 +static inline int group_to_ip(unsigned int group)
57 +{
58 +       switch (mips_machtype) {
59 +               case MACH_ARUBA_AP70:
60 +                       return group + 2;
61 +               case MACH_ARUBA_AP65:
62 +               case MACH_ARUBA_AP60:
63 +               default:
64 +                       return 6;
65 +       }
66 +}
67 +
68 +static inline void enable_local_irq(unsigned int irq)
69 +{
70 +       clear_c0_cause(0x100 << irq);
71 +       set_c0_status(0x100 << irq);
72 +       irq_enable_hazard();
73 +}
74 +
75 +static inline void disable_local_irq(unsigned int irq)
76 +{
77 +       clear_c0_status(0x100 << irq);
78 +       clear_c0_cause(0x100 << irq);
79 +       irq_disable_hazard();
80 +}
81 +
82 +static inline void aruba_irq_enable(unsigned int irq)
83 +{
84 +       unsigned long flags;
85 +       unsigned int  group, intr_bit;
86 +       volatile unsigned int  *addr;
87 +
88 +       local_irq_save(flags);
89 +
90 +       if (irq < GROUP0_IRQ_BASE) {
91 +               enable_local_irq(irq);
92 +       } else {
93 +               int ip = irq - GROUP0_IRQ_BASE;
94 +               switch (mips_machtype) {
95 +                       case MACH_ARUBA_AP70:
96 +                               // irqs are in groups of 32
97 +                               // ip is set to the remainder
98 +                               group = ip >> 5;
99 +                               ip &= 0x1f;
100 +
101 +                               // bit -> 0 = unmask
102 +                               intr_bit = 1 << ip;
103 +                               addr = intr_group_muscat[group].base_addr;
104 +                               WRITE_MASK_MUSCAT(addr, READ_MASK_MUSCAT(addr) & ~intr_bit);
105 +                               break;
106 +
107 +                       case MACH_ARUBA_AP65:
108 +                       case MACH_ARUBA_AP60:
109 +                               group = 0;
110 +
111 +                               // bit -> 1 = unmasked
112 +                               intr_bit = 1 << ip;
113 +                               addr = intr_group_merlot[group].base_addr;
114 +                               WRITE_MASK_MERLOT(addr, READ_MASK_MERLOT(addr) | intr_bit);
115 +                               break;
116 +               }
117 +               enable_local_irq(group_to_ip(group));
118 +       }
119 +
120 +       back_to_back_c0_hazard();
121 +       local_irq_restore(flags);
122 +}
123 +
124 +static void aruba_irq_disable(unsigned int irq)
125 +{
126 +       unsigned long flags;
127 +       unsigned int  group, intr_bit, mask;
128 +       volatile unsigned int  *addr;
129 +
130 +       local_irq_save(flags);
131 +
132 +       if (irq < GROUP0_IRQ_BASE) {
133 +               disable_local_irq(irq);
134 +       } else {
135 +               int ip = irq - GROUP0_IRQ_BASE;
136 +               switch (mips_machtype) {
137 +                       case MACH_ARUBA_AP70:
138 +                               idt_gpio->gpioistat &= ~(1 << ip);
139 +
140 +                               // irqs are in groups of 32
141 +                               // ip is set to the remainder
142 +                               group = ip >> 5;
143 +                               ip &= 0x1f;
144 +
145 +                               // bit -> 1 = mask
146 +                               intr_bit = 1 << ip;
147 +                               addr = intr_group_muscat[group].base_addr;
148 +
149 +                               mask = READ_MASK_MUSCAT(addr);
150 +                               mask |= intr_bit;
151 +                               WRITE_MASK_MUSCAT(addr, mask);
152 +
153 +                               if (mask == intr_group_muscat[group].mask) {
154 +                                       disable_local_irq(group_to_ip(group));
155 +                               }
156 +                               break;
157 +
158 +                       case MACH_ARUBA_AP65:
159 +                       case MACH_ARUBA_AP60:
160 +                               group = 0;
161 +
162 +                               // bit -> 0 = masked
163 +                               intr_bit = 1 << ip;
164 +                               addr = intr_group_merlot[group].base_addr;
165 +
166 +                               mask = READ_MASK_MERLOT(addr);
167 +                               mask &= ~intr_bit;
168 +                               WRITE_MASK_MERLOT(addr, mask);
169 +
170 +                               if (mask == intr_group_merlot[group].mask) {
171 +                                       disable_local_irq(group_to_ip(group));
172 +                               }
173 +                               break;
174 +               }
175 +       }
176 +
177 +       back_to_back_c0_hazard();
178 +       local_irq_restore(flags);
179 +}
180 +
181 +static unsigned int aruba_irq_startup(unsigned int irq)
182 +{
183 +       aruba_irq_enable(irq);
184 +       return 0;
185 +}
186 +
187 +#define aruba_irq_shutdown aruba_irq_disable
188 +
189 +static void aruba_irq_ack(unsigned int irq)
190 +{
191 +       aruba_irq_disable(irq);
192 +}
193 +
194 +static void aruba_irq_end(unsigned int irq)
195 +{
196 +       if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
197 +               aruba_irq_enable(irq);
198 +}
199 +
200 +static struct hw_interrupt_type aruba_irq_type = {
201 +       .typename       = "ARUBA",
202 +       .startup        = aruba_irq_startup,
203 +       .shutdown       = aruba_irq_shutdown,
204 +       .enable         = aruba_irq_enable,
205 +       .disable        = aruba_irq_disable,
206 +       .ack            = aruba_irq_ack,
207 +       .end            = aruba_irq_end,
208 +};
209 +
210 +void __init arch_init_irq(void)
211 +{
212 +       int i;
213 +       printk("Initializing IRQ's: %d out of %d\n", RC32434_NR_IRQS, NR_IRQS);
214 +       memset(irq_desc, 0, sizeof(irq_desc));
215 +
216 +       for (i = 0; i < RC32434_NR_IRQS; i++) {
217 +               irq_desc[i].status = IRQ_DISABLED;
218 +               irq_desc[i].action = NULL;
219 +               irq_desc[i].depth = 1;
220 +               irq_desc[i].handler = &aruba_irq_type;
221 +               spin_lock_init(&irq_desc[i].lock);
222 +       }
223 +}
224 +
225 +/* Main Interrupt dispatcher */
226 +
227 +void plat_irq_dispatch(struct pt_regs *regs)
228 +{
229 +       unsigned int pend, group, ip;
230 +       volatile unsigned int *addr;
231 +       unsigned long cp0_cause = read_c0_cause() & read_c0_status() & CAUSEF_IP;
232 +
233 +       if (cp0_cause & CAUSEF_IP7)
234 +               return aruba_timer_interrupt(regs);
235 +
236 +       if(cp0_cause == 0) {
237 +               printk("INTERRUPT(S) FIRED WHILE MASKED\n");
238 +#ifdef ARUBA_DEBUG
239 +               // debuging use -- figure out which interrupt(s) fired
240 +               cp0_cause = read_c0_cause() & CAUSEF_IP;
241 +               while (cp0_cause) {
242 +                       unsigned long intr_bit;
243 +                       unsigned int irq_nr;
244 +                       intr_bit = (31 - rc32434_clz(cp0_cause));
245 +                       irq_nr = intr_bit - GROUP0_IRQ_BASE;
246 +                       printk(" ---> MASKED IRQ %d\n",irq_nr);
247 +                       cp0_cause &= ~(1 << intr_bit);
248 +               }
249 +#endif
250 +               return;
251 +       }
252 +
253 +       switch (mips_machtype) {
254 +               case MACH_ARUBA_AP70:
255 +                       if ((ip = (cp0_cause & 0x7c00))) {
256 +                               group = 21 - rc32434_clz(ip);
257 +               
258 +                               addr = intr_group_muscat[group].base_addr;
259 +               
260 +                               pend = READ_PEND_MUSCAT(addr);
261 +                               pend &= ~READ_MASK_MUSCAT(addr); // only unmasked interrupts
262 +                               pend = 39 - rc32434_clz(pend);
263 +                               do_IRQ(pend + (group << 5), regs);
264 +                       }
265 +                       break;
266 +               case MACH_ARUBA_AP65:
267 +               case MACH_ARUBA_AP60:
268 +               default:
269 +                       if (cp0_cause & 0x4000) { // 1 << (8 +6) == irq 6
270 +                               // Misc Interrupt
271 +                               group = 0;
272 +
273 +                               addr = intr_group_merlot[group].base_addr;
274 +
275 +                               pend = READ_PEND_MERLOT(addr);
276 +                               pend &= READ_MASK_MERLOT(addr); // only unmasked interrupts
277 +                               pend = 31 - rc32434_clz(pend);
278 +                               do_IRQ(pend + GROUP0_IRQ_BASE, regs);
279 +                       }
280 +                       if ((ip = (cp0_cause & 0x3c00))) { // irq 2-5
281 +                               pend = 31 - rc32434_clz(ip);
282 +                               do_IRQ(pend - GROUP0_IRQ_BASE, regs);
283 +                       }
284 +                       break;
285 +       }
286 +}