sa11x0_irq.S revision 1.16 1 /* $NetBSD: sa11x0_irq.S,v 1.16 2012/08/29 07:06:27 matt Exp $ */
2
3 /*
4 * Copyright (c) 1998 Mark Brinicombe.
5 * Copyright (c) 1998 Causality Limited
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to the NetBSD Foundation
9 * by IWAMOTO Toshihiro.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by Mark Brinicombe
22 * for the NetBSD Project.
23 * 4. The name of the company nor the name of the author may be used to
24 * endorse or promote products derived from this software without specific
25 * prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
28 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
29 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
30 * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
31 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
32 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
33 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 */
39
40 #include "opt_irqstats.h"
41
42 #include "assym.h"
43 #include <machine/asm.h>
44 #include <machine/cpu.h>
45 #include <machine/frame.h>
46 #include <arm/sa11x0/sa11x0_reg.h>
47
48
49 .text
50 .align 0
51
52 Lspl_masks:
53 .word _C_LABEL(spl_masks)
54
55 Lcpu_info_store:
56 .word _C_LABEL(cpu_info_store)
57
58 .globl _C_LABEL(saipic_base)
59 _C_LABEL(saipic_base):
60 .word 0x00000000
61
62 #ifdef INTR_DEBUG
63 Ldbg_str:
64 .asciz "irq_entry %x %x\n"
65 .align 5
66 #endif
67
68 LOCK_CAS_CHECK_LOCALS
69
70 AST_ALIGNMENT_FAULT_LOCALS
71
72 /*
73 * Register usage
74 *
75 * r4 - Pointer to cpu_info
76 * r5 - Pointer to handler pointer list
77 * r6 - Address of current handler
78 * r7 - pspr mode
79 * r8 - Current IRQ requests.
80 * r9 - Used to count through possible IRQ bits.
81 * r10 - Base address of SAIP
82 */
83
84 ASENTRY_NP(irq_entry)
85 sub lr, lr, #0x00000004 /* Adjust the lr */
86
87 PUSHFRAMEINSVC /* Push an interrupt frame */
88 ENABLE_ALIGNMENT_FAULTS
89
90 /* Load r8 with the SAIPIC interrupt requests */
91
92 ldr r10, _C_LABEL(saipic_base)
93 ldr r8, [r10, #(SAIPIC_IP)] /* Load IRQ pending register */
94
95 #ifdef INTR_DEBUG
96 ldr r2, [r10, #(SAIPIC_MR)]
97 adr r0, Ldbg_str
98 mov r1, r8
99 bl _C_LABEL(printf)
100 #endif
101 /*
102 * Note that we have entered the IRQ handler.
103 * We are in SVC mode so we cannot use the processor mode
104 * to determine if we are in an IRQ. Instead we will count the
105 * each time the interrupt handler is nested.
106 */
107
108 ldr r1, [r4, #CI_INTR_DEPTH]
109 add r1, r1, #1
110 str r1, [r4, #CI_INTR_DEPTH]
111
112 /*
113 * Need to block all interrupts at the IPL or lower for
114 * all asserted interrupts.
115 * This basically emulates hardware interrupt priority levels.
116 * Means we need to go through the interrupt mask and for
117 * every asserted interrupt we need to mask out all other
118 * interrupts at the same or lower IPL.
119 * If only we could wait until the main loop but we need to sort
120 * this out first so interrupts can be re-enabled.
121 *
122 * This would benefit from a special ffs type routine
123 */
124
125 mov r9, #(NIPL - 1)
126 ldr r5, Lspl_masks
127
128 Lfind_highest_ipl:
129 ldr r2, [r5, r9, lsl #2]
130 tst r8, r2
131 subeq r9, r9, #1
132 beq Lfind_highest_ipl
133
134 /* r9 = SPL level of highest priority interrupt */
135 add r9, r9, #1
136 ldr r2, [r5, r9, lsl #2]
137
138 ldr r1, [r4, #CI_CPL]
139 str r9, [r4, #CI_CPL]
140 stmfd sp!, {r1}
141
142 /* Update the SAIP irq masks */
143 bl _C_LABEL(irq_setmasks)
144
145 #ifdef INTR_DEBUG
146 stmfd sp!, {r0,r1,r2}
147 adr r0, Ldbg_str
148 mov r1, #1
149 mov r2, r9
150 bl _C_LABEL(printf)
151 ldmia sp!, {r0,r1,r2}
152 #endif
153 mrs r0, cpsr_all /* Enable IRQs */
154 bic r0, r0, #I32_bit
155 msr cpsr_all, r0
156
157 ldr r5, Lirqhandlers
158 mov r9, #0x00000001
159
160 irqloop:
161 /* This would benefit from a special ffs type routine */
162 tst r8, r9 /* Is a bit set ? */
163 beq nextirq /* No ? try next bit */
164
165 ldr r6, [r5] /* Get address of first handler structure */
166
167 teq r6, #0x00000000 /* Do we have a handler */
168 moveq r0, r8 /* IRQ requests as arg 0 */
169 beq _C_LABEL(stray_irqhandler) /* call special handler */
170
171 ldr r0, [r4, #(CI_CC_NINTR)]
172 ldr r1, [r4, #(CI_CC_NINTR+4)]
173 #ifdef _ARMEL
174 adds r0, r0, #0x00000001
175 adc r1, r1, #0x00000001
176 #else
177 adds r1, r1, #0x00000001
178 adc r0, r0, #0x00000000
179 #endif
180 str r0, [r4, #(CI_CC_NINTR)]
181 str r1, [r4, #(CI_CC_NINTR+4)]
182
183 /*
184 * XXX: Should stats be accumulated for every interrupt routine
185 * called or for every physical interrupt that is serviced.
186 */
187
188 #ifdef IRQSTATS
189 ldr r0, Lintrcnt
190 ldr r1, [r6, #(IH_COUNT)]
191
192 add r0, r0, r1, lsl #2
193 ldr r1, [r0]
194 add r1, r1, #0x00000001
195 str r1, [r0]
196 #endif /* IRQSTATS */
197
198 irqchainloop:
199 #ifdef INTR_DEBUG
200 stmfd sp!, {r0,r1,r2}
201 adr r0, Ldbg_str
202 mov r1, #2
203 bl _C_LABEL(printf)
204 ldmia sp!, {r0,r1,r2}
205 #endif
206 ldr r0, [r6, #(IH_ARG)] /* Get argument pointer */
207 teq r0, #0x00000000 /* If arg is zero pass stack frame */
208 addeq r0, sp, #4 /* ... stack frame [XXX needs care] */
209 mov lr, pc /* return address */
210 ldr pc, [r6, #(IH_FUNC)] /* Call handler */
211
212 teq r0, #0x00000001 /* Was the irq serviced ? */
213 beq irqdone
214
215 ldr r6, [r6, #(IH_NEXT)]
216 teq r6, #0x00000000
217 bne irqchainloop
218
219 irqdone:
220 nextirq:
221 add r5, r5, #0x00000004 /* update pointer to handlers */
222 mov r9, r9, lsl #1 /* move on to next bit */
223 teq r9, #(1 << 31) /* done the last bit ? */
224 bne irqloop /* no - loop back. */
225
226 ldmfd sp!, {r2}
227 str r2, [r4, #CI_CPL]
228
229 /* Restore previous disabled mask */
230 bl _C_LABEL(irq_setmasks)
231
232 #ifdef __HAVE_FAST_SOFTINTS
233 bl _C_LABEL(dosoftints) /* Handle the soft interrupts */
234 #endif
235
236 /* Kill IRQ's in preparation for exit */
237 mrs r0, cpsr_all
238 orr r0, r0, #(I32_bit)
239 msr cpsr_all, r0
240
241 #ifdef INTR_DEBUG
242 adr r0, Ldbg_str
243 mov r1, #3
244 ldr r2, [r10, #(SAIPIC_MR)]
245 bl _C_LABEL(printf)
246 #endif
247
248 /* Decrement the nest count */
249 ldr r1, [r4, #CI_INTR_DEPTH]
250 sub r1, r1, #1
251 str r1, [r4, #CI_INTR_DEPTH]
252
253 LOCK_CAS_CHECK
254
255 DO_AST_AND_RESTORE_ALIGNMENT_FAULTS
256 PULLFRAMEFROMSVCANDEXIT
257
258 /* NOT REACHED */
259 b . - 8
260
261 ENTRY(irq_setmasks)
262 stmfd sp!, {r0, r1, r4, lr} /* Preserve registers */
263
264 /* Disable interrupts */
265 mrs r1, cpsr_all
266 orr r3, r1, #(I32_bit)
267 msr cpsr_all, r3
268
269 /* Calculate interrupt mask */
270 ldr r0, Lspl_masks
271 ldr r4, Lcpu_info_store
272 ldr r2, [r4, #CI_CPL]
273 ldr r2, [r0, r2, lsl #2]
274
275 ldr r0, _C_LABEL(saipic_base)
276 str r2, [r0, #(SAIPIC_MR)] /* Set mask register */
277
278 /* Restore old cpsr and exit */
279 msr cpsr_all, r1
280 ldmia sp!, {r0, r1, r4, pc} /* Restore registers */
281
282 #ifdef IRQSTATS
283 Lintrcnt:
284 .word _C_LABEL(intrcnt)
285 #endif
286
287 Lirqhandlers:
288 .word _C_LABEL(irqhandlers) /* Pointer to array of irqhandlers */
289
290
291 #ifdef IRQSTATS
292 .global _C_LABEL(intrnames), _C_LABEL(eintrnames)
293 .global _C_LABEL(eintrcnt)
294 _C_LABEL(intrnames):
295 _C_LABEL(eintrnames):
296 _C_LABEL(eintrcnt):
297
298 .globl _C_LABEL(intrcnt), _C_LABEL(sintrcnt)
299
300 _C_LABEL(intrcnt):
301 .space ICU_LEN*4 /* XXX Should be linked to number of interrupts */
302
303 _C_LABEL(sintrcnt):
304 .space 32*4
305 #endif
306