xref: /openbmc/qemu/target/hppa/int_helper.c (revision ba632924)
1 /*
2  *  HPPA interrupt helper routines
3  *
4  *  Copyright (c) 2017 Richard Henderson
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 "qemu/main-loop.h"
22 #include "qemu/log.h"
23 #include "cpu.h"
24 #include "exec/helper-proto.h"
25 #include "qom/cpu.h"
26 
27 #ifndef CONFIG_USER_ONLY
28 static void eval_interrupt(HPPACPU *cpu)
29 {
30     CPUState *cs = CPU(cpu);
31     if (cpu->env.cr[CR_EIRR] & cpu->env.cr[CR_EIEM]) {
32         cpu_interrupt(cs, CPU_INTERRUPT_HARD);
33     } else {
34         cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
35     }
36 }
37 
38 /* Each CPU has a word mapped into the GSC bus.  Anything on the GSC bus
39  * can write to this word to raise an external interrupt on the target CPU.
40  * This includes the system controler (DINO) for regular devices, or
41  * another CPU for SMP interprocessor interrupts.
42  */
43 static uint64_t io_eir_read(void *opaque, hwaddr addr, unsigned size)
44 {
45     HPPACPU *cpu = opaque;
46 
47     /* ??? What does a read of this register over the GSC bus do?  */
48     return cpu->env.cr[CR_EIRR];
49 }
50 
51 static void io_eir_write(void *opaque, hwaddr addr,
52                          uint64_t data, unsigned size)
53 {
54     HPPACPU *cpu = opaque;
55     int le_bit = ~data & (TARGET_REGISTER_BITS - 1);
56 
57     cpu->env.cr[CR_EIRR] |= (target_ureg)1 << le_bit;
58     eval_interrupt(cpu);
59 }
60 
61 const MemoryRegionOps hppa_io_eir_ops = {
62     .read = io_eir_read,
63     .write = io_eir_write,
64     .valid.min_access_size = 4,
65     .valid.max_access_size = 4,
66     .impl.min_access_size = 4,
67     .impl.max_access_size = 4,
68 };
69 
70 void hppa_cpu_alarm_timer(void *opaque)
71 {
72     /* Raise interrupt 0.  */
73     io_eir_write(opaque, 0, 0, 4);
74 }
75 
76 void HELPER(write_eirr)(CPUHPPAState *env, target_ureg val)
77 {
78     env->cr[CR_EIRR] &= ~val;
79     qemu_mutex_lock_iothread();
80     eval_interrupt(hppa_env_get_cpu(env));
81     qemu_mutex_unlock_iothread();
82 }
83 
84 void HELPER(write_eiem)(CPUHPPAState *env, target_ureg val)
85 {
86     env->cr[CR_EIEM] = val;
87     qemu_mutex_lock_iothread();
88     eval_interrupt(hppa_env_get_cpu(env));
89     qemu_mutex_unlock_iothread();
90 }
91 #endif /* !CONFIG_USER_ONLY */
92 
93 void hppa_cpu_do_interrupt(CPUState *cs)
94 {
95     HPPACPU *cpu = HPPA_CPU(cs);
96     CPUHPPAState *env = &cpu->env;
97     int i = cs->exception_index;
98     target_ureg iaoq_f = env->iaoq_f;
99     target_ureg iaoq_b = env->iaoq_b;
100     uint64_t iasq_f = env->iasq_f;
101     uint64_t iasq_b = env->iasq_b;
102 
103 #ifndef CONFIG_USER_ONLY
104     target_ureg old_psw;
105 
106     /* As documented in pa2.0 -- interruption handling.  */
107     /* step 1 */
108     env->cr[CR_IPSW] = old_psw = cpu_hppa_get_psw(env);
109 
110     /* step 2 -- note PSW_W == 0 for !HPPA64.  */
111     cpu_hppa_put_psw(env, PSW_W | (i == EXCP_HPMC ? PSW_M : 0));
112 
113     /* step 3 */
114     env->cr[CR_IIASQ] = iasq_f >> 32;
115     env->cr_back[0] = iasq_b >> 32;
116     env->cr[CR_IIAOQ] = iaoq_f;
117     env->cr_back[1] = iaoq_b;
118 
119     if (old_psw & PSW_Q) {
120         /* step 5 */
121         /* ISR and IOR will be set elsewhere.  */
122         switch (i) {
123         case EXCP_ILL:
124         case EXCP_BREAK:
125         case EXCP_PRIV_REG:
126         case EXCP_PRIV_OPR:
127             /* IIR set via translate.c.  */
128             break;
129 
130         case EXCP_OVERFLOW:
131         case EXCP_COND:
132         case EXCP_ASSIST:
133         case EXCP_DTLB_MISS:
134         case EXCP_NA_ITLB_MISS:
135         case EXCP_NA_DTLB_MISS:
136         case EXCP_DMAR:
137         case EXCP_DMPI:
138         case EXCP_UNALIGN:
139         case EXCP_DMP:
140         case EXCP_DMB:
141         case EXCP_TLB_DIRTY:
142         case EXCP_PAGE_REF:
143         case EXCP_ASSIST_EMU:
144             {
145                 /* Avoid reading directly from the virtual address, lest we
146                    raise another exception from some sort of TLB issue.  */
147                 /* ??? An alternate fool-proof method would be to store the
148                    instruction data into the unwind info.  That's probably
149                    a bit too much in the way of extra storage required.  */
150                 vaddr vaddr;
151                 hwaddr paddr;
152 
153                 paddr = vaddr = iaoq_f & -4;
154                 if (old_psw & PSW_C) {
155                     int prot, t;
156 
157                     vaddr = hppa_form_gva_psw(old_psw, iasq_f, vaddr);
158                     t = hppa_get_physical_address(env, vaddr, MMU_KERNEL_IDX,
159                                                   0, &paddr, &prot);
160                     if (t >= 0) {
161                         /* We can't re-load the instruction.  */
162                         env->cr[CR_IIR] = 0;
163                         break;
164                     }
165                 }
166                 env->cr[CR_IIR] = ldl_phys(cs->as, paddr);
167             }
168             break;
169 
170         default:
171             /* Other exceptions do not set IIR.  */
172             break;
173         }
174 
175         /* step 6 */
176         env->shadow[0] = env->gr[1];
177         env->shadow[1] = env->gr[8];
178         env->shadow[2] = env->gr[9];
179         env->shadow[3] = env->gr[16];
180         env->shadow[4] = env->gr[17];
181         env->shadow[5] = env->gr[24];
182         env->shadow[6] = env->gr[25];
183     }
184 
185     /* step 7 */
186     env->iaoq_f = env->cr[CR_IVA] + 32 * i;
187     env->iaoq_b = env->iaoq_f + 4;
188     env->iasq_f = 0;
189     env->iasq_b = 0;
190 #endif
191 
192     if (qemu_loglevel_mask(CPU_LOG_INT)) {
193         static const char * const names[] = {
194             [EXCP_HPMC]          = "high priority machine check",
195             [EXCP_POWER_FAIL]    = "power fail interrupt",
196             [EXCP_RC]            = "recovery counter trap",
197             [EXCP_EXT_INTERRUPT] = "external interrupt",
198             [EXCP_LPMC]          = "low priority machine check",
199             [EXCP_ITLB_MISS]     = "instruction tlb miss fault",
200             [EXCP_IMP]           = "instruction memory protection trap",
201             [EXCP_ILL]           = "illegal instruction trap",
202             [EXCP_BREAK]         = "break instruction trap",
203             [EXCP_PRIV_OPR]      = "privileged operation trap",
204             [EXCP_PRIV_REG]      = "privileged register trap",
205             [EXCP_OVERFLOW]      = "overflow trap",
206             [EXCP_COND]          = "conditional trap",
207             [EXCP_ASSIST]        = "assist exception trap",
208             [EXCP_DTLB_MISS]     = "data tlb miss fault",
209             [EXCP_NA_ITLB_MISS]  = "non-access instruction tlb miss",
210             [EXCP_NA_DTLB_MISS]  = "non-access data tlb miss",
211             [EXCP_DMP]           = "data memory protection trap",
212             [EXCP_DMB]           = "data memory break trap",
213             [EXCP_TLB_DIRTY]     = "tlb dirty bit trap",
214             [EXCP_PAGE_REF]      = "page reference trap",
215             [EXCP_ASSIST_EMU]    = "assist emulation trap",
216             [EXCP_HPT]           = "high-privilege transfer trap",
217             [EXCP_LPT]           = "low-privilege transfer trap",
218             [EXCP_TB]            = "taken branch trap",
219             [EXCP_DMAR]          = "data memory access rights trap",
220             [EXCP_DMPI]          = "data memory protection id trap",
221             [EXCP_UNALIGN]       = "unaligned data reference trap",
222             [EXCP_PER_INTERRUPT] = "performance monitor interrupt",
223             [EXCP_SYSCALL]       = "syscall",
224             [EXCP_SYSCALL_LWS]   = "syscall-lws",
225         };
226         static int count;
227         const char *name = NULL;
228         char unknown[16];
229 
230         if (i >= 0 && i < ARRAY_SIZE(names)) {
231             name = names[i];
232         }
233         if (!name) {
234             snprintf(unknown, sizeof(unknown), "unknown %d", i);
235             name = unknown;
236         }
237         qemu_log("INT %6d: %s @ " TARGET_FMT_lx "," TARGET_FMT_lx
238                  " -> " TREG_FMT_lx " " TARGET_FMT_lx "\n",
239                  ++count, name,
240                  hppa_form_gva(env, iasq_f, iaoq_f),
241                  hppa_form_gva(env, iasq_b, iaoq_b),
242                  env->iaoq_f,
243                  hppa_form_gva(env, (uint64_t)env->cr[CR_ISR] << 32,
244                                env->cr[CR_IOR]));
245     }
246     cs->exception_index = -1;
247 }
248 
249 bool hppa_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
250 {
251 #ifndef CONFIG_USER_ONLY
252     HPPACPU *cpu = HPPA_CPU(cs);
253     CPUHPPAState *env = &cpu->env;
254 
255     /* If interrupts are requested and enabled, raise them.  */
256     if ((env->psw & PSW_I) && (interrupt_request & CPU_INTERRUPT_HARD)) {
257         cs->exception_index = EXCP_EXT_INTERRUPT;
258         hppa_cpu_do_interrupt(cs);
259         return true;
260     }
261 #endif
262     return false;
263 }
264