i80200_irq.S revision 1.9 1 /* $NetBSD: i80200_irq.S,v 1.9 2002/10/25 14:29:37 briggs 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 .word _C_LABEL(prev_intr_depth)
60
61 .Lintr_dispatch:
62 .word _C_LABEL(i80200_extirq_dispatch)
63
64 #if defined(PERFCTRS)
65 .Lpmc_dispatch:
66 .word _C_LABEL(xscale_pmc_dispatch)
67 #endif
68
69 .Lastpending:
70 .word _C_LABEL(astpending)
71
72 ASENTRY_NP(irq_entry)
73 sub lr, lr, #0x00000004 /* Adjust the lr */
74
75 PUSHFRAMEINSVC /* Push an interrupt frame */
76
77 /*
78 * Note that we have entered the IRQ handler. We are
79 * in SVC mode so we cannot use the processor mode to
80 * determine if we are in an IRQ. Instead, we will
81 * count each time the interrupt handler is nested.
82 */
83 ldr r0, .Lcurrent_intr_depth
84 ldr r2, .Lcurrent_intr_depth+4
85 ldr r1, [r0]
86 str r1, [r2]
87 add r1, r1, #1
88 str r1, [r0]
89
90 /*
91 * Get the interrupt status into a callee-save register.
92 */
93 mrc p13, 0, r4, c4, c0, 0
94
95 #if defined(PERFCTRS)
96 /*
97 * Check for PMU interrupts.
98 * If we have one, call the routine to handle it.
99 */
100 tst r4, #(INTSRC_PI)
101 beq .Lpmc_intr_return
102 mov r1, r4
103 mov r0, sp
104 mov lr, pc
105 ldr pc, .Lpmc_dispatch
106 .Lpmc_intr_return:
107 #endif
108
109 /*
110 * XXX - any need to handle BMU interrupts?
111 */
112
113 /*
114 * Check for external IRQs. If we have one, call the
115 * external IRQ dispatcher. The argument is a pointer
116 * to the stack frame. This function will be called with
117 * interrupts disabled, and will return with interrupts
118 * disabled.
119 */
120 tst r4, #(INTSRC_II)
121 beq .Lextirq_return /* no external IRQ pending */
122 ldr r1, .Lintr_dispatch
123 mov r0, sp
124 mov lr, pc
125 ldr pc, [r1]
126 .Lextirq_return:
127
128 /* Decremement the nest count. */
129 ldr r0, .Lcurrent_intr_depth
130 ldr r2, .Lcurrent_intr_depth+4
131 ldr r1, [r0]
132 str r1, [r2]
133 sub r1, r1, #1
134 str r1, [r0]
135
136 /*
137 * If we're returning to user mode, check for pending ASTs.
138 */
139 ldr r0, [sp] /* Get the SPSR from stack */
140 and r0, r0, #(PSR_MODE) /* Test for USR32 mode before the IRQ */
141 teq r0, #(PSR_USR32_MODE)
142 bne .Lirqout /* Nope, get out now */
143
144 .Lastloop:
145 ldr r0, .Lastpending /* Do we have an AST pending? */
146 ldr r1, [r0]
147 teq r1, #0x00000000
148 beq .Lirqout /* Nope, get out now */
149
150 mov r1, #0x00000000
151 str r1, [r0] /* Clear astpending */
152
153 mrs r4, cpsr /* save CPSR */
154 bic r0, r4, #(I32_bit) /* Enable IRQs */
155 msr cpsr_c, r0
156
157 mov r0, sp
158 bl _C_LABEL(ast) /* ast(frame) */
159
160 msr cpsr_c, r4 /* Disable IRQs */
161 b .Lastloop /* Check for more ASTs */
162
163 .Lirqout:
164 PULLFRAMEFROMSVCANDEXIT
165 movs pc, lr /* Exit */
166
167 .bss
168 .align 0
169
170 .global _C_LABEL(astpending)
171 _C_LABEL(astpending):
172 .word 0
173
174 .global _C_LABEL(current_intr_depth)
175 _C_LABEL(current_intr_depth):
176 .word 0
177
178 .global _C_LABEL(prev_intr_depth)
179 _C_LABEL(prev_intr_depth):
180 .word 0
181
182 /*
183 * XXX Provide intrnames/intrcnt for legacy code, but
184 * don't actually use them.
185 */
186
187 .global _C_LABEL(intrnames), _C_LABEL(eintrnames)
188 .global _C_LABEL(intrcnt), _C_LABEL(eintrcnt)
189 _C_LABEL(intrnames):
190 _C_LABEL(eintrnames):
191
192 .global _C_LABEL(intrcnt), _C_LABEL(sintrcnt), _C_LABEL(eintrcnt)
193 _C_LABEL(intrcnt):
194 _C_LABEL(eintrcnt):
195