xref: /qemu/target/microblaze/helper.c (revision cc944932ecef3b7a56ae62d89dd92fb9e56c5cc8)
1 /*
2  *  MicroBlaze helper routines.
3  *
4  *  Copyright (c) 2009 Edgar E. Iglesias <edgar.iglesias@gmail.com>
5  *  Copyright (c) 2009-2012 PetaLogix Qld Pty Ltd.
6  *
7  * This library is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * This library is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include "qemu/osdep.h"
22 #include "cpu.h"
23 #include "exec/cputlb.h"
24 #include "accel/tcg/cpu-mmu-index.h"
25 #include "exec/page-protection.h"
26 #include "qemu/host-utils.h"
27 #include "exec/log.h"
28 
29 #ifndef CONFIG_USER_ONLY
30 static bool mb_cpu_access_is_secure(MicroBlazeCPU *cpu,
31                                     MMUAccessType access_type)
32 {
33     if (access_type == MMU_INST_FETCH) {
34         return !cpu->ns_axi_ip;
35     } else {
36         return !cpu->ns_axi_dp;
37     }
38 }
39 
40 bool mb_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
41                      MMUAccessType access_type, int mmu_idx,
42                      bool probe, uintptr_t retaddr)
43 {
44     MicroBlazeCPU *cpu = MICROBLAZE_CPU(cs);
45     CPUMBState *env = &cpu->env;
46     MicroBlazeMMULookup lu;
47     unsigned int hit;
48     int prot;
49     MemTxAttrs attrs = {};
50 
51     attrs.secure = mb_cpu_access_is_secure(cpu, access_type);
52 
53     if (mmu_idx == MMU_NOMMU_IDX) {
54         /* MMU disabled or not available.  */
55         address &= TARGET_PAGE_MASK;
56         prot = PAGE_RWX;
57         tlb_set_page_with_attrs(cs, address, address, attrs, prot, mmu_idx,
58                                 TARGET_PAGE_SIZE);
59         return true;
60     }
61 
62     hit = mmu_translate(cpu, &lu, address, access_type, mmu_idx);
63     if (likely(hit)) {
64         uint32_t vaddr = address & TARGET_PAGE_MASK;
65         uint32_t paddr = lu.paddr + vaddr - lu.vaddr;
66 
67         qemu_log_mask(CPU_LOG_MMU, "MMU map mmu=%d v=%x p=%x prot=%x\n",
68                       mmu_idx, vaddr, paddr, lu.prot);
69         tlb_set_page_with_attrs(cs, vaddr, paddr, attrs, lu.prot, mmu_idx,
70                                 TARGET_PAGE_SIZE);
71         return true;
72     }
73 
74     /* TLB miss.  */
75     if (probe) {
76         return false;
77     }
78 
79     qemu_log_mask(CPU_LOG_MMU, "mmu=%d miss v=%" VADDR_PRIx "\n",
80                   mmu_idx, address);
81 
82     env->ear = address;
83     switch (lu.err) {
84     case ERR_PROT:
85         env->esr = access_type == MMU_INST_FETCH ? 17 : 16;
86         env->esr |= (access_type == MMU_DATA_STORE) << 10;
87         break;
88     case ERR_MISS:
89         env->esr = access_type == MMU_INST_FETCH ? 19 : 18;
90         env->esr |= (access_type == MMU_DATA_STORE) << 10;
91         break;
92     default:
93         abort();
94     }
95 
96     if (cs->exception_index == EXCP_MMU) {
97         cpu_abort(cs, "recursive faults\n");
98     }
99 
100     /* TLB miss.  */
101     cs->exception_index = EXCP_MMU;
102     cpu_loop_exit_restore(cs, retaddr);
103 }
104 
105 void mb_cpu_do_interrupt(CPUState *cs)
106 {
107     MicroBlazeCPU *cpu = MICROBLAZE_CPU(cs);
108     CPUMBState *env = &cpu->env;
109     uint32_t t, msr = mb_cpu_read_msr(env);
110     bool set_esr;
111 
112     /* IMM flag cannot propagate across a branch and into the dslot.  */
113     assert((env->iflags & (D_FLAG | IMM_FLAG)) != (D_FLAG | IMM_FLAG));
114     /* BIMM flag cannot be set without D_FLAG. */
115     assert((env->iflags & (D_FLAG | BIMM_FLAG)) != BIMM_FLAG);
116     /* RTI flags are private to translate. */
117     assert(!(env->iflags & (DRTI_FLAG | DRTE_FLAG | DRTB_FLAG)));
118 
119     switch (cs->exception_index) {
120     case EXCP_HW_EXCP:
121         if (!(cpu->cfg.pvr_regs[0] & PVR0_USE_EXC_MASK)) {
122             qemu_log_mask(LOG_GUEST_ERROR,
123                           "Exception raised on system without exceptions!\n");
124             return;
125         }
126 
127         qemu_log_mask(CPU_LOG_INT,
128                       "INT: HWE at pc=%08x msr=%08x iflags=%x\n",
129                       env->pc, msr, env->iflags);
130 
131         /* Exception breaks branch + dslot sequence?  */
132         set_esr = true;
133         env->esr &= ~D_FLAG;
134         if (env->iflags & D_FLAG) {
135             env->esr |= D_FLAG;
136             env->btr = env->btarget;
137         }
138 
139         /* Exception in progress. */
140         msr |= MSR_EIP;
141         env->regs[17] = env->pc + 4;
142         env->pc = cpu->cfg.base_vectors + 0x20;
143         break;
144 
145     case EXCP_MMU:
146         qemu_log_mask(CPU_LOG_INT,
147                       "INT: MMU at pc=%08x msr=%08x "
148                       "ear=%" PRIx64 " iflags=%x\n",
149                       env->pc, msr, env->ear, env->iflags);
150 
151         /* Exception breaks branch + dslot sequence? */
152         set_esr = true;
153         env->esr &= ~D_FLAG;
154         if (env->iflags & D_FLAG) {
155             env->esr |= D_FLAG;
156             env->btr = env->btarget;
157             /* Reexecute the branch. */
158             env->regs[17] = env->pc - (env->iflags & BIMM_FLAG ? 8 : 4);
159         } else if (env->iflags & IMM_FLAG) {
160             /* Reexecute the imm. */
161             env->regs[17] = env->pc - 4;
162         } else {
163             env->regs[17] = env->pc;
164         }
165 
166         /* Exception in progress. */
167         msr |= MSR_EIP;
168         env->pc = cpu->cfg.base_vectors + 0x20;
169         break;
170 
171     case EXCP_IRQ:
172         assert(!(msr & (MSR_EIP | MSR_BIP)));
173         assert(msr & MSR_IE);
174         assert(!(env->iflags & (D_FLAG | IMM_FLAG)));
175 
176         qemu_log_mask(CPU_LOG_INT,
177                       "INT: DEV at pc=%08x msr=%08x iflags=%x\n",
178                       env->pc, msr, env->iflags);
179         set_esr = false;
180 
181         /* Disable interrupts.  */
182         msr &= ~MSR_IE;
183         env->regs[14] = env->pc;
184         env->pc = cpu->cfg.base_vectors + 0x10;
185         break;
186 
187     case EXCP_HW_BREAK:
188         assert(!(env->iflags & (D_FLAG | IMM_FLAG)));
189 
190         qemu_log_mask(CPU_LOG_INT,
191                       "INT: BRK at pc=%08x msr=%08x iflags=%x\n",
192                       env->pc, msr, env->iflags);
193         set_esr = false;
194 
195         /* Break in progress. */
196         msr |= MSR_BIP;
197         env->regs[16] = env->pc;
198         env->pc = cpu->cfg.base_vectors + 0x18;
199         break;
200 
201     default:
202         cpu_abort(cs, "unhandled exception type=%d\n", cs->exception_index);
203         /* not reached */
204     }
205 
206     /* Save previous mode, disable mmu, disable user-mode. */
207     t = (msr & (MSR_VM | MSR_UM)) << 1;
208     msr &= ~(MSR_VMS | MSR_UMS | MSR_VM | MSR_UM);
209     msr |= t;
210     mb_cpu_write_msr(env, msr);
211 
212     env->res_addr = RES_ADDR_NONE;
213     env->iflags = 0;
214 
215     if (!set_esr) {
216         qemu_log_mask(CPU_LOG_INT,
217                       "         to pc=%08x msr=%08x\n", env->pc, msr);
218     } else if (env->esr & D_FLAG) {
219         qemu_log_mask(CPU_LOG_INT,
220                       "         to pc=%08x msr=%08x esr=%04x btr=%08x\n",
221                       env->pc, msr, env->esr, env->btr);
222     } else {
223         qemu_log_mask(CPU_LOG_INT,
224                       "         to pc=%08x msr=%08x esr=%04x\n",
225                       env->pc, msr, env->esr);
226     }
227 }
228 
229 hwaddr mb_cpu_get_phys_page_attrs_debug(CPUState *cs, vaddr addr,
230                                         MemTxAttrs *attrs)
231 {
232     MicroBlazeCPU *cpu = MICROBLAZE_CPU(cs);
233     target_ulong vaddr, paddr = 0;
234     MicroBlazeMMULookup lu;
235     int mmu_idx = cpu_mmu_index(cs, false);
236     unsigned int hit;
237 
238     /* Caller doesn't initialize */
239     *attrs = (MemTxAttrs) {};
240     attrs->secure = mb_cpu_access_is_secure(cpu, MMU_DATA_LOAD);
241 
242     if (mmu_idx != MMU_NOMMU_IDX) {
243         hit = mmu_translate(cpu, &lu, addr, 0, 0);
244         if (hit) {
245             vaddr = addr & TARGET_PAGE_MASK;
246             paddr = lu.paddr + vaddr - lu.vaddr;
247         } else
248             paddr = 0; /* ???.  */
249     } else
250         paddr = addr & TARGET_PAGE_MASK;
251 
252     return paddr;
253 }
254 
255 bool mb_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
256 {
257     CPUMBState *env = cpu_env(cs);
258 
259     if ((interrupt_request & CPU_INTERRUPT_HARD)
260         && (env->msr & MSR_IE)
261         && !(env->msr & (MSR_EIP | MSR_BIP))
262         && !(env->iflags & (D_FLAG | IMM_FLAG))) {
263         cs->exception_index = EXCP_IRQ;
264         mb_cpu_do_interrupt(cs);
265         return true;
266     }
267     return false;
268 }
269 
270 #endif /* !CONFIG_USER_ONLY */
271 
272 void mb_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
273                                 MMUAccessType access_type,
274                                 int mmu_idx, uintptr_t retaddr)
275 {
276     MicroBlazeCPU *cpu = MICROBLAZE_CPU(cs);
277     uint32_t esr, iflags;
278 
279     /* Recover the pc and iflags from the corresponding insn_start.  */
280     cpu_restore_state(cs, retaddr);
281     iflags = cpu->env.iflags;
282 
283     qemu_log_mask(CPU_LOG_INT,
284                   "Unaligned access addr=" TARGET_FMT_lx " pc=%x iflags=%x\n",
285                   (target_ulong)addr, cpu->env.pc, iflags);
286 
287     esr = ESR_EC_UNALIGNED_DATA;
288     if (likely(iflags & ESR_ESS_FLAG)) {
289         esr |= iflags & ESR_ESS_MASK;
290     } else {
291         qemu_log_mask(LOG_UNIMP, "Unaligned access without ESR_ESS_FLAG\n");
292     }
293 
294     cpu->env.ear = addr;
295     cpu->env.esr = esr;
296     cs->exception_index = EXCP_HW_EXCP;
297     cpu_loop_exit(cs);
298 }
299