xref: /openbmc/qemu/target/openrisc/interrupt.c (revision 80e5db30)
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 
36     env->epcr = env->pc;
37     if (env->flags & D_FLAG) {
38         env->flags &= ~D_FLAG;
39         env->sr |= SR_DSX;
40         env->epcr -= 4;
41     }
42     if (cs->exception_index == EXCP_SYSCALL) {
43         env->epcr += 4;
44     }
45 
46     /* For machine-state changed between user-mode and supervisor mode,
47        we need flush TLB when we enter&exit EXCP.  */
48     tlb_flush(cs);
49 
50     env->esr = env->sr;
51     env->sr &= ~SR_DME;
52     env->sr &= ~SR_IME;
53     env->sr |= SR_SM;
54     env->sr &= ~SR_IEE;
55     env->sr &= ~SR_TEE;
56     env->tlb->cpu_openrisc_map_address_data = &cpu_openrisc_get_phys_nommu;
57     env->tlb->cpu_openrisc_map_address_code = &cpu_openrisc_get_phys_nommu;
58 
59     if (cs->exception_index > 0 && cs->exception_index < EXCP_NR) {
60         env->pc = (cs->exception_index << 8);
61     } else {
62         cpu_abort(cs, "Unhandled exception 0x%x\n", cs->exception_index);
63     }
64 #endif
65 
66     cs->exception_index = -1;
67 }
68 
69 bool openrisc_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
70 {
71     OpenRISCCPU *cpu = OPENRISC_CPU(cs);
72     CPUOpenRISCState *env = &cpu->env;
73     int idx = -1;
74 
75     if ((interrupt_request & CPU_INTERRUPT_HARD) && (env->sr & SR_IEE)) {
76         idx = EXCP_INT;
77     }
78     if ((interrupt_request & CPU_INTERRUPT_TIMER) && (env->sr & SR_TEE)) {
79         idx = EXCP_TICK;
80     }
81     if (idx >= 0) {
82         cs->exception_index = idx;
83         openrisc_cpu_do_interrupt(cs);
84         return true;
85     }
86     return false;
87 }
88