xref: /netbsd-src/sys/arch/arm/xscale/i80200_irq.S (revision 1ffa7b76c40339c17a0fb2a09fac93f287cfc046)
1/*	$NetBSD: i80200_irq.S,v 1.10 2003/01/02 23:54:41 thorpej Exp $	*/
2
3/*
4 * Copyright (c) 2002 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Jason R. Thorpe for Wasabi Systems, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *	This product includes software developed for the NetBSD Project by
20 *	Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 *    or promote products derived from this software without specific prior
23 *    written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38#include "assym.h"
39#include "opt_perfctrs.h"
40
41#include <machine/asm.h>
42#include <machine/cpu.h>
43#include <machine/frame.h>
44
45#include <arm/xscale/i80200reg.h>
46
47/*
48 * irq_entry:
49 *
50 *	Main entry point for the IRQ vector on i80200 CPUs.  Calls
51 *	board-specific external interrupt dispatch routine.
52 */
53
54	.text
55	.align	0
56
57.Lcurrent_intr_depth:
58	.word	_C_LABEL(current_intr_depth)
59
60.Lintr_dispatch:
61	.word	_C_LABEL(i80200_extirq_dispatch)
62
63#if defined(PERFCTRS)
64.Lpmc_dispatch:
65	.word	_C_LABEL(xscale_pmc_dispatch)
66#endif
67
68.Lastpending:
69	.word	_C_LABEL(astpending)
70
71ASENTRY_NP(irq_entry)
72	sub	lr, lr, #0x00000004	/* Adjust the lr */
73
74	PUSHFRAMEINSVC			/* Push an interrupt frame */
75
76	/*
77	 * Note that we have entered the IRQ handler.  We are
78	 * in SVC mode so we cannot use the processor mode to
79	 * determine if we are in an IRQ.  Instead, we will
80	 * count each time the interrupt handler is nested.
81	 */
82	ldr	r0, .Lcurrent_intr_depth
83	ldr	r1, [r0]
84	add	r1, r1, #1
85	str	r1, [r0]
86
87	/*
88	 * Get the interrupt status into a callee-save register.
89	 */
90	mrc	p13, 0, r4, c4, c0, 0
91
92#if defined(PERFCTRS)
93	/*
94	 * Check for PMU interrupts.
95	 * If we have one, call the routine to handle it.
96	 */
97	tst	r4, #(INTSRC_PI)
98	beq	.Lpmc_intr_return
99	mov	r1, r4
100	mov	r0, sp
101	mov	lr, pc
102	ldr	pc, .Lpmc_dispatch
103.Lpmc_intr_return:
104#endif
105
106	/*
107	 * XXX - any need to handle BMU interrupts?
108	 */
109
110	/*
111	 * Check for external IRQs.  If we have one, call the
112	 * external IRQ dispatcher.  The argument is a pointer
113	 * to the stack frame.  This function will be called with
114	 * interrupts disabled, and will return with interrupts
115	 * disabled.
116	 */
117	tst	r4, #(INTSRC_II)
118	beq	.Lextirq_return		/* no external IRQ pending */
119	ldr	r1, .Lintr_dispatch
120	mov	r0, sp
121	mov	lr, pc
122	ldr	pc, [r1]
123.Lextirq_return:
124
125	/* Decremement the nest count. */
126	ldr	r0, .Lcurrent_intr_depth
127	ldr	r1, [r0]
128	sub	r1, r1, #1
129	str	r1, [r0]
130
131	/*
132	 * If we're returning to user mode, check for pending ASTs.
133	 */
134	ldr	r0, [sp]		/* Get the SPSR from stack */
135	and	r0, r0, #(PSR_MODE)	/* Test for USR32 mode before the IRQ */
136	teq	r0, #(PSR_USR32_MODE)
137	bne	.Lirqout		/* Nope, get out now */
138
139.Lastloop:
140	ldr	r0, .Lastpending	/* Do we have an AST pending? */
141	ldr	r1, [r0]
142	teq	r1, #0x00000000
143	beq	.Lirqout		/* Nope, get out now */
144
145	mov	r1, #0x00000000
146	str	r1, [r0]		/* Clear astpending */
147
148	mrs	r4, cpsr		/* save CPSR */
149	bic	r0, r4, #(I32_bit)	/* Enable IRQs */
150	msr	cpsr_c, r0
151
152	mov	r0, sp
153	bl	_C_LABEL(ast)		/* ast(frame) */
154
155	msr	cpsr_c, r4		/* Disable IRQs */
156	b	.Lastloop		/* Check for more ASTs */
157
158.Lirqout:
159	PULLFRAMEFROMSVCANDEXIT
160	movs	pc, lr			/* Exit */
161
162	.bss
163	.align	0
164
165	.global _C_LABEL(astpending)
166_C_LABEL(astpending):
167	.word	0
168
169	.global	_C_LABEL(current_intr_depth)
170_C_LABEL(current_intr_depth):
171	.word	0
172
173	/*
174	 * XXX Provide intrnames/intrcnt for legacy code, but
175	 * don't actually use them.
176	 */
177
178	.global _C_LABEL(intrnames), _C_LABEL(eintrnames)
179	.global _C_LABEL(intrcnt), _C_LABEL(eintrcnt)
180_C_LABEL(intrnames):
181_C_LABEL(eintrnames):
182
183	.global _C_LABEL(intrcnt), _C_LABEL(sintrcnt), _C_LABEL(eintrcnt)
184_C_LABEL(intrcnt):
185_C_LABEL(eintrcnt):
186