i80200_irq.S revision 1.8 1 /* $NetBSD: i80200_irq.S,v 1.8 2002/10/21 18:09:18 bjh21 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 #endif
107
108 /*
109 * XXX - any need to handle BMU interrupts?
110 */
111
112 /*
113 * Check for external IRQs. If we have one, call the
114 * external IRQ dispatcher. The argument is a pointer
115 * to the stack frame. This function will be called with
116 * interrupts disabled, and will return with interrupts
117 * disabled.
118 */
119 tst r4, #(INTSRC_II)
120 beq .Lextirq_return /* no external IRQ pending */
121 ldr r1, .Lintr_dispatch
122 mov r0, sp
123 mov lr, pc
124 ldr pc, [r1]
125 .Lextirq_return:
126
127 /* Decremement the nest count. */
128 ldr r0, .Lcurrent_intr_depth
129 ldr r2, .Lcurrent_intr_depth+4
130 ldr r1, [r0]
131 str r1, [r2]
132 sub r1, r1, #1
133 str r1, [r0]
134
135 /*
136 * If we're returning to user mode, check for pending ASTs.
137 */
138 ldr r0, [sp] /* Get the SPSR from stack */
139 and r0, r0, #(PSR_MODE) /* Test for USR32 mode before the IRQ */
140 teq r0, #(PSR_USR32_MODE)
141 bne .Lirqout /* Nope, get out now */
142
143 .Lastloop:
144 ldr r0, .Lastpending /* Do we have an AST pending? */
145 ldr r1, [r0]
146 teq r1, #0x00000000
147 beq .Lirqout /* Nope, get out now */
148
149 mov r1, #0x00000000
150 str r1, [r0] /* Clear astpending */
151
152 mrs r4, cpsr /* save CPSR */
153 bic r0, r4, #(I32_bit) /* Enable IRQs */
154 msr cpsr_c, r0
155
156 mov r0, sp
157 bl _C_LABEL(ast) /* ast(frame) */
158
159 msr cpsr_c, r4 /* Disable IRQs */
160 b .Lastloop /* Check for more ASTs */
161
162 .Lirqout:
163 PULLFRAMEFROMSVCANDEXIT
164 movs pc, lr /* Exit */
165
166 .bss
167 .align 0
168
169 .global _C_LABEL(astpending)
170 _C_LABEL(astpending):
171 .word 0
172
173 .global _C_LABEL(current_intr_depth)
174 _C_LABEL(current_intr_depth):
175 .word 0
176
177 .global _C_LABEL(prev_intr_depth)
178 _C_LABEL(prev_intr_depth):
179 .word 0
180
181 /*
182 * XXX Provide intrnames/intrcnt for legacy code, but
183 * don't actually use them.
184 */
185
186 .global _C_LABEL(intrnames), _C_LABEL(eintrnames)
187 .global _C_LABEL(intrcnt), _C_LABEL(eintrcnt)
188 _C_LABEL(intrnames):
189 _C_LABEL(eintrnames):
190
191 .global _C_LABEL(intrcnt), _C_LABEL(sintrcnt), _C_LABEL(eintrcnt)
192 _C_LABEL(intrcnt):
193 _C_LABEL(eintrcnt):
194