xref: /openbmc/qemu/hw/xtensa/pic_cpu.c (revision 4921d0a7)
1 /*
2  * Copyright (c) 2011, Max Filippov, Open Source and Linux Lab.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  *     * Redistributions of source code must retain the above copyright
8  *       notice, this list of conditions and the following disclaimer.
9  *     * Redistributions in binary form must reproduce the above copyright
10  *       notice, this list of conditions and the following disclaimer in the
11  *       documentation and/or other materials provided with the distribution.
12  *     * Neither the name of the Open Source and Linux Lab nor the
13  *       names of its contributors may be used to endorse or promote products
14  *       derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
20  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
23  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include "qemu/osdep.h"
29 #include "cpu.h"
30 #include "hw/irq.h"
31 #include "qemu/log.h"
32 #include "qemu/timer.h"
33 #include "qemu/atomic.h"
34 
35 void check_interrupts(CPUXtensaState *env)
36 {
37     CPUState *cs = env_cpu(env);
38     int minlevel = xtensa_get_cintlevel(env);
39     uint32_t int_set_enabled = env->sregs[INTSET] &
40         (env->sregs[INTENABLE] | env->config->inttype_mask[INTTYPE_NMI]);
41     int level;
42 
43     if (minlevel >= env->config->nmi_level) {
44         minlevel = env->config->nmi_level - 1;
45     }
46     for (level = env->config->nlevel; level > minlevel; --level) {
47         if (env->config->level_mask[level] & int_set_enabled) {
48             env->pending_irq_level = level;
49             cpu_interrupt(cs, CPU_INTERRUPT_HARD);
50             qemu_log_mask(CPU_LOG_INT,
51                     "%s level = %d, cintlevel = %d, "
52                     "pc = %08x, a0 = %08x, ps = %08x, "
53                     "intset = %08x, intenable = %08x, "
54                     "ccount = %08x\n",
55                     __func__, level, xtensa_get_cintlevel(env),
56                     env->pc, env->regs[0], env->sregs[PS],
57                     env->sregs[INTSET], env->sregs[INTENABLE],
58                     env->sregs[CCOUNT]);
59             return;
60         }
61     }
62     env->pending_irq_level = 0;
63     cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
64 }
65 
66 static void xtensa_set_irq(void *opaque, int irq, int active)
67 {
68     CPUXtensaState *env = opaque;
69 
70     if (irq >= env->config->ninterrupt) {
71         qemu_log("%s: bad IRQ %d\n", __func__, irq);
72     } else {
73         uint32_t irq_bit = 1 << irq;
74 
75         if (active) {
76             qatomic_or(&env->sregs[INTSET], irq_bit);
77         } else if (env->config->interrupt[irq].inttype == INTTYPE_LEVEL) {
78             qatomic_and(&env->sregs[INTSET], ~irq_bit);
79         }
80 
81         check_interrupts(env);
82     }
83 }
84 
85 static void xtensa_ccompare_cb(void *opaque)
86 {
87     XtensaCcompareTimer *ccompare = opaque;
88     CPUXtensaState *env = ccompare->env;
89     unsigned i = ccompare - env->ccompare;
90 
91     qemu_set_irq(env->irq_inputs[env->config->timerint[i]], 1);
92 }
93 
94 static void xtensa_set_runstall(void *opaque, int irq, int active)
95 {
96     CPUXtensaState *env = opaque;
97     xtensa_runstall(env, active);
98 }
99 
100 void xtensa_irq_init(CPUXtensaState *env)
101 {
102     unsigned i;
103 
104     env->irq_inputs = qemu_allocate_irqs(xtensa_set_irq, env,
105                                          env->config->ninterrupt);
106     if (xtensa_option_enabled(env->config, XTENSA_OPTION_TIMER_INTERRUPT)) {
107         env->time_base = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
108         env->ccount_base = env->sregs[CCOUNT];
109         for (i = 0; i < env->config->nccompare; ++i) {
110             env->ccompare[i].env = env;
111             env->ccompare[i].timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
112                     xtensa_ccompare_cb, env->ccompare + i);
113         }
114     }
115     for (i = 0; i < env->config->nextint; ++i) {
116         unsigned irq = env->config->extint[i];
117 
118         env->ext_irq_inputs[i] = env->irq_inputs[irq];
119     }
120     env->runstall_irq = qemu_allocate_irq(xtensa_set_runstall, env, 0);
121 }
122 
123 qemu_irq *xtensa_get_extints(CPUXtensaState *env)
124 {
125     return env->ext_irq_inputs;
126 }
127 
128 qemu_irq xtensa_get_runstall(CPUXtensaState *env)
129 {
130     return env->runstall_irq;
131 }
132