xref: /netbsd-src/sys/arch/arm/sa11x0/sa11x0_irq.S (revision 8ac07aec990b9d2e483062509d0a9fa5b4f57cf2)
1/*	$NetBSD: sa11x0_irq.S,v 1.12 2008/01/08 02:07:52 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
52Lcurrent_spl_level:
53	.word	_C_LABEL(current_spl_level)
54
55Lcurrent_intr_depth:
56	.word	_C_LABEL(cpu_info_store) + CI_IDEPTH
57
58Lspl_masks:
59	.word	_C_LABEL(spl_masks)
60
61	.globl	_C_LABEL(saipic_base)
62_C_LABEL(saipic_base):
63	.word	0x00000000
64
65#ifdef INTR_DEBUG
66Ldbg_str:
67	.asciz	"irq_entry %x %x\n"
68#endif
69
70LOCK_CAS_CHECK_LOCALS
71
72AST_ALIGNMENT_FAULT_LOCALS
73
74/*
75 * Register usage
76 *
77 *  r6  - Address of current handler
78 *  r7  - Pointer to handler pointer list
79 *  r8  - Current IRQ requests.
80 *  r9  - Used to count through possible IRQ bits.
81 *  r10 - Base address of SAIP
82 */
83
84ASENTRY_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	r0, Lcurrent_intr_depth
109	ldr	r1, [r0]
110	add	r1, r1, #1
111	str	r1, [r0]
112
113	/*
114 	 * Need to block all interrupts at the IPL or lower for
115	 * all asserted interrupts.
116	 * This basically emulates hardware interrupt priority levels.
117	 * Means we need to go through the interrupt mask and for
118	 * every asserted interrupt we need to mask out all other
119	 * interrupts at the same or lower IPL.
120	 * If only we could wait until the main loop but we need to sort
121	 * this out first so interrupts can be re-enabled.
122	 *
123	 * This would benefit from a special ffs type routine
124	 */
125
126	mov	r9, #(_SPL_LEVELS - 1)
127	ldr	r7, Lspl_masks
128
129Lfind_highest_ipl:
130	ldr	r2, [r7, r9, lsl #2]
131	tst	r8, r2
132	subeq	r9, r9, #1
133	beq	Lfind_highest_ipl
134
135	/* r9 = SPL level of highest priority interrupt */
136	add	r9, r9, #1
137	ldr	r2, [r7, r9, lsl #2]
138	mvn	r2, r2
139
140	ldr	r0, Lcurrent_spl_level
141	ldr	r1, [r0]
142	str	r9, [r0]
143	stmfd	sp!, {r1}
144
145	/* Update the SAIP irq masks */
146	bl	_C_LABEL(irq_setmasks)
147
148#ifdef INTR_DEBUG
149	stmfd	sp!, {r0,r1,r2}
150	adr	r0, Ldbg_str
151	mov	r1, #1
152	mov	r2, r9
153	bl	_C_LABEL(printf)
154	ldmia	sp!, {r0,r1,r2}
155#endif
156        mrs     r0, cpsr_all		/* Enable IRQs */
157	bic	r0, r0, #I32_bit
158	msr	cpsr_all, r0
159
160	ldr	r7, Lirqhandlers
161        mov	r9, #0x00000001
162
163irqloop:
164	/* This would benefit from a special ffs type routine */
165	tst	r8, r9			/* Is a bit set ? */
166	beq	nextirq			/* No ? try next bit */
167
168	ldr	r6, [r7]		/* Get address of first handler structure */
169
170	teq	r6, #0x00000000		/* Do we have a handler */
171	moveq	r0, r8			/* IRQ requests as arg 0 */
172	beq	_C_LABEL(stray_irqhandler) /* call special handler */
173
174        ldr	r0, Lcnt		/* Stat info */
175	ldr	r1, [r0, #(V_INTR)]
176	add	r1, r1, #0x00000001
177	str	r1, [r0, #(V_INTR)]
178
179	/*
180	 * XXX: Should stats be accumulated for every interrupt routine
181	 * called or for every physical interrupt that is serviced.
182	 */
183
184#ifdef IRQSTATS
185	ldr	r0, Lintrcnt
186	ldr	r1, [r6, #(IH_COUNT)]
187
188	add	r0, r0, r1, lsl #2
189	ldr	r1, [r0]
190	add	r1, r1, #0x00000001
191	str	r1, [r0]
192#endif	/* IRQSTATS */
193
194irqchainloop:
195#ifdef INTR_DEBUG
196	stmfd	sp!, {r0,r1,r2}
197	adr	r0, Ldbg_str
198	mov	r1, #2
199	bl	_C_LABEL(printf)
200	ldmia	sp!, {r0,r1,r2}
201#endif
202	ldr	r0, [r6, #(IH_ARG)]	/* Get argument pointer */
203	teq	r0, #0x00000000		/* If arg is zero pass stack frame */
204	addeq	r0, sp, #4		/* ... stack frame [XXX needs care] */
205	mov	lr, pc			/* return address */
206	ldr	pc, [r6, #(IH_FUNC)]	/* Call handler */
207
208	teq	r0, #0x00000001		/* Was the irq serviced ? */
209	beq	irqdone
210
211	ldr	r6, [r6, #(IH_NEXT)]
212	teq	r6, #0x00000000
213	bne	irqchainloop
214
215irqdone:
216nextirq:
217	add	r7, r7, #0x00000004	/* update pointer to handlers */
218	mov	r9, r9, lsl #1		/* move on to next bit */
219	teq	r9, #(1 << 31)		/* done the last bit ? */
220	bne	irqloop			/* no - loop back. */
221
222	ldmfd	sp!, {r2}
223	ldr	r1, Lcurrent_spl_level
224	str	r2, [r1]
225
226	/* Restore previous disabled mask */
227	bl	_C_LABEL(irq_setmasks)
228
229#ifdef __HAVE_FAST_SOFTINTS
230	bl	_C_LABEL(dosoftints)	/* Handle the soft interrupts */
231#endif
232
233	/* Kill IRQ's in preparation for exit */
234        mrs     r0, cpsr_all
235        orr     r0, r0, #(I32_bit)
236        msr     cpsr_all, r0
237
238#ifdef INTR_DEBUG
239	adr	r0, Ldbg_str
240	mov	r1, #3
241	ldr	r2, [r10, #(SAIPIC_MR)]
242	bl	_C_LABEL(printf)
243#endif
244
245	/* Decrement the nest count */
246	ldr	r0, Lcurrent_intr_depth
247	ldr	r1, [r0]
248	sub	r1, r1, #1
249	str	r1, [r0]
250
251	LOCK_CAS_CHECK
252
253	DO_AST_AND_RESTORE_ALIGNMENT_FAULTS
254	PULLFRAMEFROMSVCANDEXIT
255
256	/* NOT REACHED */
257	b	. - 8
258
259ENTRY(irq_setmasks)
260	/* Disable interrupts */
261	mrs	r3, cpsr_all
262	orr	r1, r3,  #(I32_bit)
263	msr	cpsr_all, r1
264
265	/* Calculate interrupt mask */
266	ldr	r0, Lspl_masks
267	ldr	r2, Lcurrent_spl_level
268	ldr	r2, [r2]
269	ldr	r2, [r0, r2, lsl #2]
270
271	ldr	r0, _C_LABEL(saipic_base)
272	str	r2, [r0, #(SAIPIC_MR)]	/* Set mask register */
273
274	/* Restore old cpsr and exit */
275	msr	cpsr_all, r3
276	mov	pc, lr
277
278Lcnt:
279	.word	_C_LABEL(uvmexp)
280
281#ifdef IRQSTATS
282Lintrcnt:
283	.word	_C_LABEL(intrcnt)
284#endif
285
286Lirqhandlers:
287	.word	_C_LABEL(irqhandlers)	/* Pointer to array of irqhandlers */
288
289
290#ifdef IRQSTATS
291	.global _C_LABEL(intrnames), _C_LABEL(eintrnames)
292	.global _C_LABEL(eintrcnt)
293_C_LABEL(intrnames):
294_C_LABEL(eintrnames):
295_C_LABEL(eintrcnt):
296
297	.globl	_C_LABEL(intrcnt), _C_LABEL(sintrcnt)
298
299_C_LABEL(intrcnt):
300	.space	ICU_LEN*4  /* XXX Should be linked to number of interrupts */
301
302_C_LABEL(sintrcnt):
303	.space 32*4
304#endif
305