xref: /qemu/target/openrisc/interrupt.c (revision b9bed1b9ab37a6ae62e88a52cbcbd2ad81aa1056)
1 /*
2  * OpenRISC interrupt.
3  *
4  * Copyright (c) 2011-2012 Jia Liu <proljc@gmail.com>
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "cpu.h"
22 #include "exec/exec-all.h"
23 #include "qemu-common.h"
24 #include "exec/gdbstub.h"
25 #include "qemu/host-utils.h"
26 #ifndef CONFIG_USER_ONLY
27 #include "hw/loader.h"
28 #endif
29 
30 void openrisc_cpu_do_interrupt(CPUState *cs)
31 {
32 #ifndef CONFIG_USER_ONLY
33     OpenRISCCPU *cpu = OPENRISC_CPU(cs);
34     CPUOpenRISCState *env = &cpu->env;
35     int exception = cs->exception_index;
36 
37     env->epcr = env->pc;
38     if (env->dflag) {
39         env->dflag = 0;
40         env->sr |= SR_DSX;
41         env->epcr -= 4;
42     } else {
43         env->sr &= ~SR_DSX;
44     }
45     if (exception == EXCP_SYSCALL) {
46         env->epcr += 4;
47     }
48     /* When we have an illegal instruction the error effective address
49        shall be set to the illegal instruction address.  */
50     if (exception == EXCP_ILLEGAL) {
51         env->eear = env->pc;
52     }
53 
54     env->esr = cpu_get_sr(env);
55     env->sr &= ~SR_DME;
56     env->sr &= ~SR_IME;
57     env->sr |= SR_SM;
58     env->sr &= ~SR_IEE;
59     env->sr &= ~SR_TEE;
60     env->pmr &= ~PMR_DME;
61     env->pmr &= ~PMR_SME;
62     env->lock_addr = -1;
63 
64     if (exception > 0 && exception < EXCP_NR) {
65         static const char * const int_name[EXCP_NR] = {
66             [EXCP_RESET]    = "RESET",
67             [EXCP_BUSERR]   = "BUSERR (bus error)",
68             [EXCP_DPF]      = "DFP (data protection fault)",
69             [EXCP_IPF]      = "IPF (code protection fault)",
70             [EXCP_TICK]     = "TICK (timer interrupt)",
71             [EXCP_ALIGN]    = "ALIGN",
72             [EXCP_ILLEGAL]  = "ILLEGAL",
73             [EXCP_INT]      = "INT (device interrupt)",
74             [EXCP_DTLBMISS] = "DTLBMISS (data tlb miss)",
75             [EXCP_ITLBMISS] = "ITLBMISS (code tlb miss)",
76             [EXCP_RANGE]    = "RANGE",
77             [EXCP_SYSCALL]  = "SYSCALL",
78             [EXCP_FPE]      = "FPE",
79             [EXCP_TRAP]     = "TRAP",
80         };
81 
82         qemu_log_mask(CPU_LOG_INT, "INT: %s\n", int_name[exception]);
83 
84         hwaddr vect_pc = exception << 8;
85         if (env->cpucfgr & CPUCFGR_EVBARP) {
86             vect_pc |= env->evbar;
87         }
88         if (env->sr & SR_EPH) {
89             vect_pc |= 0xf0000000;
90         }
91         env->pc = vect_pc;
92     } else {
93         cpu_abort(cs, "Unhandled exception 0x%x\n", exception);
94     }
95 #endif
96 
97     cs->exception_index = -1;
98 }
99 
100 bool openrisc_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
101 {
102     OpenRISCCPU *cpu = OPENRISC_CPU(cs);
103     CPUOpenRISCState *env = &cpu->env;
104     int idx = -1;
105 
106     if ((interrupt_request & CPU_INTERRUPT_HARD) && (env->sr & SR_IEE)) {
107         idx = EXCP_INT;
108     }
109     if ((interrupt_request & CPU_INTERRUPT_TIMER) && (env->sr & SR_TEE)) {
110         idx = EXCP_TICK;
111     }
112     if (idx >= 0) {
113         cs->exception_index = idx;
114         openrisc_cpu_do_interrupt(cs);
115         return true;
116     }
117     return false;
118 }
119