xref: /openbmc/qemu/target/hppa/int_helper.c (revision a6caeee8)
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 2.1 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 "hw/core/cpu.h"
26 #include "hw/hppa/hppa_hardware.h"
27 
28 #ifndef CONFIG_USER_ONLY
29 static void eval_interrupt(HPPACPU *cpu)
30 {
31     CPUState *cs = CPU(cpu);
32     if (cpu->env.cr[CR_EIRR] & cpu->env.cr[CR_EIEM]) {
33         cpu_interrupt(cs, CPU_INTERRUPT_HARD);
34     } else {
35         cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
36     }
37 }
38 
39 /* Each CPU has a word mapped into the GSC bus.  Anything on the GSC bus
40  * can write to this word to raise an external interrupt on the target CPU.
41  * This includes the system controler (DINO) for regular devices, or
42  * another CPU for SMP interprocessor interrupts.
43  */
44 static uint64_t io_eir_read(void *opaque, hwaddr addr, unsigned size)
45 {
46     HPPACPU *cpu = opaque;
47 
48     /* ??? What does a read of this register over the GSC bus do?  */
49     return cpu->env.cr[CR_EIRR];
50 }
51 
52 static void io_eir_write(void *opaque, hwaddr addr,
53                          uint64_t data, unsigned size)
54 {
55     HPPACPU *cpu = opaque;
56     int le_bit = ~data & (TARGET_REGISTER_BITS - 1);
57 
58     cpu->env.cr[CR_EIRR] |= (target_ureg)1 << le_bit;
59     eval_interrupt(cpu);
60 }
61 
62 const MemoryRegionOps hppa_io_eir_ops = {
63     .read = io_eir_read,
64     .write = io_eir_write,
65     .valid.min_access_size = 4,
66     .valid.max_access_size = 4,
67     .impl.min_access_size = 4,
68     .impl.max_access_size = 4,
69 };
70 
71 void hppa_cpu_alarm_timer(void *opaque)
72 {
73     /* Raise interrupt 0.  */
74     io_eir_write(opaque, 0, 0, 4);
75 }
76 
77 void HELPER(write_eirr)(CPUHPPAState *env, target_ureg val)
78 {
79     env->cr[CR_EIRR] &= ~val;
80     qemu_mutex_lock_iothread();
81     eval_interrupt(env_archcpu(env));
82     qemu_mutex_unlock_iothread();
83 }
84 
85 void HELPER(write_eiem)(CPUHPPAState *env, target_ureg val)
86 {
87     env->cr[CR_EIEM] = val;
88     qemu_mutex_lock_iothread();
89     eval_interrupt(env_archcpu(env));
90     qemu_mutex_unlock_iothread();
91 }
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     target_ureg old_psw;
104 
105     /* As documented in pa2.0 -- interruption handling.  */
106     /* step 1 */
107     env->cr[CR_IPSW] = old_psw = cpu_hppa_get_psw(env);
108 
109     /* step 2 -- note PSW_W == 0 for !HPPA64.  */
110     cpu_hppa_put_psw(env, PSW_W | (i == EXCP_HPMC ? PSW_M : 0));
111 
112     /* step 3 */
113     env->cr[CR_IIASQ] = iasq_f >> 32;
114     env->cr_back[0] = iasq_b >> 32;
115     env->cr[CR_IIAOQ] = iaoq_f;
116     env->cr_back[1] = iaoq_b;
117 
118     if (old_psw & PSW_Q) {
119         /* step 5 */
120         /* ISR and IOR will be set elsewhere.  */
121         switch (i) {
122         case EXCP_ILL:
123         case EXCP_BREAK:
124         case EXCP_PRIV_REG:
125         case EXCP_PRIV_OPR:
126             /* IIR set via translate.c.  */
127             break;
128 
129         case EXCP_OVERFLOW:
130         case EXCP_COND:
131         case EXCP_ASSIST:
132         case EXCP_DTLB_MISS:
133         case EXCP_NA_ITLB_MISS:
134         case EXCP_NA_DTLB_MISS:
135         case EXCP_DMAR:
136         case EXCP_DMPI:
137         case EXCP_UNALIGN:
138         case EXCP_DMP:
139         case EXCP_DMB:
140         case EXCP_TLB_DIRTY:
141         case EXCP_PAGE_REF:
142         case EXCP_ASSIST_EMU:
143             {
144                 /* Avoid reading directly from the virtual address, lest we
145                    raise another exception from some sort of TLB issue.  */
146                 /* ??? An alternate fool-proof method would be to store the
147                    instruction data into the unwind info.  That's probably
148                    a bit too much in the way of extra storage required.  */
149                 vaddr vaddr;
150                 hwaddr paddr;
151 
152                 paddr = vaddr = iaoq_f & -4;
153                 if (old_psw & PSW_C) {
154                     int prot, t;
155 
156                     vaddr = hppa_form_gva_psw(old_psw, iasq_f, vaddr);
157                     t = hppa_get_physical_address(env, vaddr, MMU_KERNEL_IDX,
158                                                   0, &paddr, &prot);
159                     if (t >= 0) {
160                         /* We can't re-load the instruction.  */
161                         env->cr[CR_IIR] = 0;
162                         break;
163                     }
164                 }
165                 env->cr[CR_IIR] = ldl_phys(cs->as, paddr);
166             }
167             break;
168 
169         default:
170             /* Other exceptions do not set IIR.  */
171             break;
172         }
173 
174         /* step 6 */
175         env->shadow[0] = env->gr[1];
176         env->shadow[1] = env->gr[8];
177         env->shadow[2] = env->gr[9];
178         env->shadow[3] = env->gr[16];
179         env->shadow[4] = env->gr[17];
180         env->shadow[5] = env->gr[24];
181         env->shadow[6] = env->gr[25];
182     }
183 
184     /* step 7 */
185     if (i == EXCP_TOC) {
186         env->iaoq_f = FIRMWARE_START;
187         /* help SeaBIOS and provide iaoq_b and iasq_back in shadow regs */
188         env->gr[24] = env->cr_back[0];
189         env->gr[25] = env->cr_back[1];
190     } else {
191         env->iaoq_f = env->cr[CR_IVA] + 32 * i;
192     }
193     env->iaoq_b = env->iaoq_f + 4;
194     env->iasq_f = 0;
195     env->iasq_b = 0;
196 
197     if (qemu_loglevel_mask(CPU_LOG_INT)) {
198         static const char * const names[] = {
199             [EXCP_HPMC]          = "high priority machine check",
200             [EXCP_POWER_FAIL]    = "power fail interrupt",
201             [EXCP_RC]            = "recovery counter trap",
202             [EXCP_EXT_INTERRUPT] = "external interrupt",
203             [EXCP_LPMC]          = "low priority machine check",
204             [EXCP_ITLB_MISS]     = "instruction tlb miss fault",
205             [EXCP_IMP]           = "instruction memory protection trap",
206             [EXCP_ILL]           = "illegal instruction trap",
207             [EXCP_BREAK]         = "break instruction trap",
208             [EXCP_PRIV_OPR]      = "privileged operation trap",
209             [EXCP_PRIV_REG]      = "privileged register trap",
210             [EXCP_OVERFLOW]      = "overflow trap",
211             [EXCP_COND]          = "conditional trap",
212             [EXCP_ASSIST]        = "assist exception trap",
213             [EXCP_DTLB_MISS]     = "data tlb miss fault",
214             [EXCP_NA_ITLB_MISS]  = "non-access instruction tlb miss",
215             [EXCP_NA_DTLB_MISS]  = "non-access data tlb miss",
216             [EXCP_DMP]           = "data memory protection trap",
217             [EXCP_DMB]           = "data memory break trap",
218             [EXCP_TLB_DIRTY]     = "tlb dirty bit trap",
219             [EXCP_PAGE_REF]      = "page reference trap",
220             [EXCP_ASSIST_EMU]    = "assist emulation trap",
221             [EXCP_HPT]           = "high-privilege transfer trap",
222             [EXCP_LPT]           = "low-privilege transfer trap",
223             [EXCP_TB]            = "taken branch trap",
224             [EXCP_DMAR]          = "data memory access rights trap",
225             [EXCP_DMPI]          = "data memory protection id trap",
226             [EXCP_UNALIGN]       = "unaligned data reference trap",
227             [EXCP_PER_INTERRUPT] = "performance monitor interrupt",
228             [EXCP_SYSCALL]       = "syscall",
229             [EXCP_SYSCALL_LWS]   = "syscall-lws",
230             [EXCP_TOC]           = "TOC (transfer of control)",
231         };
232         static int count;
233         const char *name = NULL;
234         char unknown[16];
235 
236         if (i >= 0 && i < ARRAY_SIZE(names)) {
237             name = names[i];
238         }
239         if (!name) {
240             snprintf(unknown, sizeof(unknown), "unknown %d", i);
241             name = unknown;
242         }
243         qemu_log("INT %6d: %s @ " TARGET_FMT_lx "," TARGET_FMT_lx
244                  " -> " TREG_FMT_lx " " TARGET_FMT_lx "\n",
245                  ++count, name,
246                  hppa_form_gva(env, iasq_f, iaoq_f),
247                  hppa_form_gva(env, iasq_b, iaoq_b),
248                  env->iaoq_f,
249                  hppa_form_gva(env, (uint64_t)env->cr[CR_ISR] << 32,
250                                env->cr[CR_IOR]));
251     }
252     cs->exception_index = -1;
253 }
254 
255 bool hppa_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
256 {
257     HPPACPU *cpu = HPPA_CPU(cs);
258     CPUHPPAState *env = &cpu->env;
259 
260     if (interrupt_request & CPU_INTERRUPT_NMI) {
261         /* Raise TOC (NMI) interrupt */
262         cpu_reset_interrupt(cs, CPU_INTERRUPT_NMI);
263         cs->exception_index = EXCP_TOC;
264         hppa_cpu_do_interrupt(cs);
265         return true;
266     }
267 
268     /* If interrupts are requested and enabled, raise them.  */
269     if ((env->psw & PSW_I) && (interrupt_request & CPU_INTERRUPT_HARD)) {
270         cs->exception_index = EXCP_EXT_INTERRUPT;
271         hppa_cpu_do_interrupt(cs);
272         return true;
273     }
274     return false;
275 }
276 
277 #endif /* !CONFIG_USER_ONLY */
278