diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/v850/kernel/gbus_int.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/v850/kernel/gbus_int.c')
-rw-r--r-- | arch/v850/kernel/gbus_int.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/arch/v850/kernel/gbus_int.c b/arch/v850/kernel/gbus_int.c new file mode 100644 index 000000000000..92918b8d89ef --- /dev/null +++ b/arch/v850/kernel/gbus_int.c | |||
@@ -0,0 +1,271 @@ | |||
1 | /* | ||
2 | * arch/v850/kernel/gbus_int.c -- Midas labs GBUS interrupt support | ||
3 | * | ||
4 | * Copyright (C) 2001,02,03 NEC Electronics Corporation | ||
5 | * Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org> | ||
6 | * | ||
7 | * This file is subject to the terms and conditions of the GNU General | ||
8 | * Public License. See the file COPYING in the main directory of this | ||
9 | * archive for more details. | ||
10 | * | ||
11 | * Written by Miles Bader <miles@gnu.org> | ||
12 | */ | ||
13 | |||
14 | #include <linux/types.h> | ||
15 | #include <linux/init.h> | ||
16 | #include <linux/irq.h> | ||
17 | #include <linux/interrupt.h> | ||
18 | #include <linux/signal.h> | ||
19 | |||
20 | #include <asm/machdep.h> | ||
21 | |||
22 | |||
23 | /* The number of shared GINT interrupts. */ | ||
24 | #define NUM_GINTS 4 | ||
25 | |||
26 | /* For each GINT interrupt, how many GBUS interrupts are using it. */ | ||
27 | static unsigned gint_num_active_irqs[NUM_GINTS] = { 0 }; | ||
28 | |||
29 | /* A table of GINTn interrupts we actually use. | ||
30 | Note that we don't use GINT0 because all the boards we support treat it | ||
31 | specially. */ | ||
32 | struct used_gint { | ||
33 | unsigned gint; | ||
34 | unsigned priority; | ||
35 | } used_gint[] = { | ||
36 | { 1, GBUS_INT_PRIORITY_HIGH }, | ||
37 | { 3, GBUS_INT_PRIORITY_LOW } | ||
38 | }; | ||
39 | #define NUM_USED_GINTS (sizeof used_gint / sizeof used_gint[0]) | ||
40 | |||
41 | /* A table of which GINT is used by each GBUS interrupts (they are | ||
42 | assigned based on priority). */ | ||
43 | static unsigned char gbus_int_gint[IRQ_GBUS_INT_NUM]; | ||
44 | |||
45 | |||
46 | /* Interrupt enabling/disabling. */ | ||
47 | |||
48 | /* Enable interrupt handling for interrupt IRQ. */ | ||
49 | void gbus_int_enable_irq (unsigned irq) | ||
50 | { | ||
51 | unsigned gint = gbus_int_gint[irq - GBUS_INT_BASE_IRQ]; | ||
52 | GBUS_INT_ENABLE (GBUS_INT_IRQ_WORD(irq), gint) | ||
53 | |= GBUS_INT_IRQ_MASK (irq); | ||
54 | } | ||
55 | |||
56 | /* Disable interrupt handling for interrupt IRQ. Note that any | ||
57 | interrupts received while disabled will be delivered once the | ||
58 | interrupt is enabled again, unless they are explicitly cleared using | ||
59 | `gbus_int_clear_pending_irq'. */ | ||
60 | void gbus_int_disable_irq (unsigned irq) | ||
61 | { | ||
62 | unsigned gint = gbus_int_gint[irq - GBUS_INT_BASE_IRQ]; | ||
63 | GBUS_INT_ENABLE (GBUS_INT_IRQ_WORD(irq), gint) | ||
64 | &= ~GBUS_INT_IRQ_MASK (irq); | ||
65 | } | ||
66 | |||
67 | /* Return true if interrupt handling for interrupt IRQ is enabled. */ | ||
68 | int gbus_int_irq_enabled (unsigned irq) | ||
69 | { | ||
70 | unsigned gint = gbus_int_gint[irq - GBUS_INT_BASE_IRQ]; | ||
71 | return (GBUS_INT_ENABLE (GBUS_INT_IRQ_WORD(irq), gint) | ||
72 | & GBUS_INT_IRQ_MASK(irq)); | ||
73 | } | ||
74 | |||
75 | /* Disable all GBUS irqs. */ | ||
76 | void gbus_int_disable_irqs () | ||
77 | { | ||
78 | unsigned w, n; | ||
79 | for (w = 0; w < GBUS_INT_NUM_WORDS; w++) | ||
80 | for (n = 0; n < IRQ_GINT_NUM; n++) | ||
81 | GBUS_INT_ENABLE (w, n) = 0; | ||
82 | } | ||
83 | |||
84 | /* Clear any pending interrupts for IRQ. */ | ||
85 | void gbus_int_clear_pending_irq (unsigned irq) | ||
86 | { | ||
87 | GBUS_INT_CLEAR (GBUS_INT_IRQ_WORD(irq)) = GBUS_INT_IRQ_MASK (irq); | ||
88 | } | ||
89 | |||
90 | /* Return true if interrupt IRQ is pending (but disabled). */ | ||
91 | int gbus_int_irq_pending (unsigned irq) | ||
92 | { | ||
93 | return (GBUS_INT_STATUS (GBUS_INT_IRQ_WORD(irq)) | ||
94 | & GBUS_INT_IRQ_MASK(irq)); | ||
95 | } | ||
96 | |||
97 | |||
98 | /* Delegating interrupts. */ | ||
99 | |||
100 | /* Handle a shared GINT interrupt by passing to the appropriate GBUS | ||
101 | interrupt handler. */ | ||
102 | static irqreturn_t gbus_int_handle_irq (int irq, void *dev_id, | ||
103 | struct pt_regs *regs) | ||
104 | { | ||
105 | unsigned w; | ||
106 | irqreturn_t rval = IRQ_NONE; | ||
107 | unsigned gint = irq - IRQ_GINT (0); | ||
108 | |||
109 | for (w = 0; w < GBUS_INT_NUM_WORDS; w++) { | ||
110 | unsigned status = GBUS_INT_STATUS (w); | ||
111 | unsigned enable = GBUS_INT_ENABLE (w, gint); | ||
112 | |||
113 | /* Only pay attention to enabled interrupts. */ | ||
114 | status &= enable; | ||
115 | if (status) { | ||
116 | irq = IRQ_GBUS_INT (w * GBUS_INT_BITS_PER_WORD); | ||
117 | do { | ||
118 | /* There's an active interrupt in word | ||
119 | W, find out which one, and call its | ||
120 | handler. */ | ||
121 | |||
122 | while (! (status & 0x1)) { | ||
123 | irq++; | ||
124 | status >>= 1; | ||
125 | } | ||
126 | status &= ~0x1; | ||
127 | |||
128 | /* Recursively call handle_irq to handle it. */ | ||
129 | handle_irq (irq, regs); | ||
130 | rval = IRQ_HANDLED; | ||
131 | } while (status); | ||
132 | } | ||
133 | } | ||
134 | |||
135 | /* Toggle the `all enable' bit back and forth, which should cause | ||
136 | another edge transition if there are any other interrupts | ||
137 | still pending, and so result in another CPU interrupt. */ | ||
138 | GBUS_INT_ENABLE (0, gint) &= ~0x1; | ||
139 | GBUS_INT_ENABLE (0, gint) |= 0x1; | ||
140 | |||
141 | return rval; | ||
142 | } | ||
143 | |||
144 | |||
145 | /* Initialize GBUS interrupt sources. */ | ||
146 | |||
147 | static void irq_nop (unsigned irq) { } | ||
148 | |||
149 | static unsigned gbus_int_startup_irq (unsigned irq) | ||
150 | { | ||
151 | unsigned gint = gbus_int_gint[irq - GBUS_INT_BASE_IRQ]; | ||
152 | |||
153 | if (gint_num_active_irqs[gint] == 0) { | ||
154 | /* First enable the CPU interrupt. */ | ||
155 | int rval = | ||
156 | request_irq (IRQ_GINT(gint), gbus_int_handle_irq, | ||
157 | SA_INTERRUPT, | ||
158 | "gbus_int_handler", | ||
159 | &gint_num_active_irqs[gint]); | ||
160 | if (rval != 0) | ||
161 | return rval; | ||
162 | } | ||
163 | |||
164 | gint_num_active_irqs[gint]++; | ||
165 | |||
166 | gbus_int_clear_pending_irq (irq); | ||
167 | gbus_int_enable_irq (irq); | ||
168 | |||
169 | return 0; | ||
170 | } | ||
171 | |||
172 | static void gbus_int_shutdown_irq (unsigned irq) | ||
173 | { | ||
174 | unsigned gint = gbus_int_gint[irq - GBUS_INT_BASE_IRQ]; | ||
175 | |||
176 | gbus_int_disable_irq (irq); | ||
177 | |||
178 | if (--gint_num_active_irqs[gint] == 0) | ||
179 | /* Disable the CPU interrupt. */ | ||
180 | free_irq (IRQ_GINT(gint), &gint_num_active_irqs[gint]); | ||
181 | } | ||
182 | |||
183 | /* Initialize HW_IRQ_TYPES for INTC-controlled irqs described in array | ||
184 | INITS (which is terminated by an entry with the name field == 0). */ | ||
185 | void __init gbus_int_init_irq_types (struct gbus_int_irq_init *inits, | ||
186 | struct hw_interrupt_type *hw_irq_types) | ||
187 | { | ||
188 | struct gbus_int_irq_init *init; | ||
189 | for (init = inits; init->name; init++) { | ||
190 | unsigned i; | ||
191 | struct hw_interrupt_type *hwit = hw_irq_types++; | ||
192 | |||
193 | hwit->typename = init->name; | ||
194 | |||
195 | hwit->startup = gbus_int_startup_irq; | ||
196 | hwit->shutdown = gbus_int_shutdown_irq; | ||
197 | hwit->enable = gbus_int_enable_irq; | ||
198 | hwit->disable = gbus_int_disable_irq; | ||
199 | hwit->ack = irq_nop; | ||
200 | hwit->end = irq_nop; | ||
201 | |||
202 | /* Initialize kernel IRQ infrastructure for this interrupt. */ | ||
203 | init_irq_handlers(init->base, init->num, init->interval, hwit); | ||
204 | |||
205 | /* Set the interrupt priorities. */ | ||
206 | for (i = 0; i < init->num; i++) { | ||
207 | unsigned j; | ||
208 | for (j = 0; j < NUM_USED_GINTS; j++) | ||
209 | if (used_gint[j].priority > init->priority) | ||
210 | break; | ||
211 | /* Wherever we stopped looking is one past the | ||
212 | GINT we want. */ | ||
213 | gbus_int_gint[init->base + i * init->interval | ||
214 | - GBUS_INT_BASE_IRQ] | ||
215 | = used_gint[j > 0 ? j - 1 : 0].gint; | ||
216 | } | ||
217 | } | ||
218 | } | ||
219 | |||
220 | |||
221 | /* Initialize IRQS. */ | ||
222 | |||
223 | /* Chip interrupts (GINTn) shared among GBUS interrupts. */ | ||
224 | static struct hw_interrupt_type gint_hw_itypes[NUM_USED_GINTS]; | ||
225 | |||
226 | |||
227 | /* GBUS interrupts themselves. */ | ||
228 | |||
229 | struct gbus_int_irq_init gbus_irq_inits[] __initdata = { | ||
230 | /* First set defaults. */ | ||
231 | { "GBUS_INT", IRQ_GBUS_INT(0), IRQ_GBUS_INT_NUM, 1, 6}, | ||
232 | { 0 } | ||
233 | }; | ||
234 | #define NUM_GBUS_IRQ_INITS \ | ||
235 | ((sizeof gbus_irq_inits / sizeof gbus_irq_inits[0]) - 1) | ||
236 | |||
237 | static struct hw_interrupt_type gbus_hw_itypes[NUM_GBUS_IRQ_INITS]; | ||
238 | |||
239 | |||
240 | /* Initialize GBUS interrupts. */ | ||
241 | void __init gbus_int_init_irqs (void) | ||
242 | { | ||
243 | unsigned i; | ||
244 | |||
245 | /* First initialize the shared gint interrupts. */ | ||
246 | for (i = 0; i < NUM_USED_GINTS; i++) { | ||
247 | unsigned gint = used_gint[i].gint; | ||
248 | struct v850e_intc_irq_init gint_irq_init[2]; | ||
249 | |||
250 | /* We initialize one GINT interrupt at a time. */ | ||
251 | gint_irq_init[0].name = "GINT"; | ||
252 | gint_irq_init[0].base = IRQ_GINT (gint); | ||
253 | gint_irq_init[0].num = 1; | ||
254 | gint_irq_init[0].interval = 1; | ||
255 | gint_irq_init[0].priority = used_gint[i].priority; | ||
256 | |||
257 | gint_irq_init[1].name = 0; /* Terminate the vector. */ | ||
258 | |||
259 | v850e_intc_init_irq_types (gint_irq_init, gint_hw_itypes); | ||
260 | } | ||
261 | |||
262 | /* Then the GBUS interrupts. */ | ||
263 | gbus_int_disable_irqs (); | ||
264 | gbus_int_init_irq_types (gbus_irq_inits, gbus_hw_itypes); | ||
265 | /* Turn on the `all enable' bits, which are ANDed with | ||
266 | individual interrupt enable bits; we only want to bother with | ||
267 | the latter. They are the first bit in the first word of each | ||
268 | interrupt-enable area. */ | ||
269 | for (i = 0; i < NUM_USED_GINTS; i++) | ||
270 | GBUS_INT_ENABLE (0, used_gint[i].gint) = 0x1; | ||
271 | } | ||