xref: /qemu/target/microblaze/helper.c (revision 3072961b6edc99abfbd87caac3de29bb58a52ccf)
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 "exec/target_page.h"
27 #include "qemu/host-utils.h"
28 #include "exec/log.h"
29 #include "exec/helper-proto.h"
30 
31 
32 G_NORETURN
mb_unaligned_access_internal(CPUState * cs,uint64_t addr,uintptr_t retaddr)33 static void mb_unaligned_access_internal(CPUState *cs, uint64_t addr,
34                                          uintptr_t retaddr)
35 {
36     CPUMBState *env = cpu_env(cs);
37     uint32_t esr, iflags;
38 
39     /* Recover the pc and iflags from the corresponding insn_start.  */
40     cpu_restore_state(cs, retaddr);
41     iflags = env->iflags;
42 
43     qemu_log_mask(CPU_LOG_INT,
44                   "Unaligned access addr=0x%" PRIx64 " pc=%x iflags=%x\n",
45                   addr, env->pc, iflags);
46 
47     esr = ESR_EC_UNALIGNED_DATA;
48     if (likely(iflags & ESR_ESS_FLAG)) {
49         esr |= iflags & ESR_ESS_MASK;
50     } else {
51         qemu_log_mask(LOG_UNIMP, "Unaligned access without ESR_ESS_FLAG\n");
52     }
53 
54     env->ear = addr;
55     env->esr = esr;
56     cs->exception_index = EXCP_HW_EXCP;
57     cpu_loop_exit(cs);
58 }
59 
mb_cpu_do_unaligned_access(CPUState * cs,vaddr addr,MMUAccessType access_type,int mmu_idx,uintptr_t retaddr)60 void mb_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
61                                 MMUAccessType access_type,
62                                 int mmu_idx, uintptr_t retaddr)
63 {
64     mb_unaligned_access_internal(cs, addr, retaddr);
65 }
66 
67 #ifndef CONFIG_USER_ONLY
68 
HELPER(unaligned_access)69 void HELPER(unaligned_access)(CPUMBState *env, uint64_t addr)
70 {
71     mb_unaligned_access_internal(env_cpu(env), addr, GETPC());
72 }
73 
mb_cpu_access_is_secure(MicroBlazeCPU * cpu,MMUAccessType access_type)74 static bool mb_cpu_access_is_secure(MicroBlazeCPU *cpu,
75                                     MMUAccessType access_type)
76 {
77     if (access_type == MMU_INST_FETCH) {
78         return !cpu->ns_axi_ip;
79     } else {
80         return !cpu->ns_axi_dp;
81     }
82 }
83 
mb_cpu_tlb_fill(CPUState * cs,vaddr address,int size,MMUAccessType access_type,int mmu_idx,bool probe,uintptr_t retaddr)84 bool mb_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
85                      MMUAccessType access_type, int mmu_idx,
86                      bool probe, uintptr_t retaddr)
87 {
88     MicroBlazeCPU *cpu = MICROBLAZE_CPU(cs);
89     CPUMBState *env = &cpu->env;
90     MicroBlazeMMULookup lu;
91     unsigned int hit;
92     int prot;
93     MemTxAttrs attrs = {};
94 
95     attrs.secure = mb_cpu_access_is_secure(cpu, access_type);
96 
97     if (mmu_idx == MMU_NOMMU_IDX) {
98         /* MMU disabled or not available.  */
99         address &= TARGET_PAGE_MASK;
100         prot = PAGE_RWX;
101         tlb_set_page_with_attrs(cs, address, address, attrs, prot, mmu_idx,
102                                 TARGET_PAGE_SIZE);
103         return true;
104     }
105 
106     hit = mmu_translate(cpu, &lu, address, access_type, mmu_idx);
107     if (likely(hit)) {
108         uint32_t vaddr = address & TARGET_PAGE_MASK;
109         uint32_t paddr = lu.paddr + vaddr - lu.vaddr;
110 
111         qemu_log_mask(CPU_LOG_MMU, "MMU map mmu=%d v=%x p=%x prot=%x\n",
112                       mmu_idx, vaddr, paddr, lu.prot);
113         tlb_set_page_with_attrs(cs, vaddr, paddr, attrs, lu.prot, mmu_idx,
114                                 TARGET_PAGE_SIZE);
115         return true;
116     }
117 
118     /* TLB miss.  */
119     if (probe) {
120         return false;
121     }
122 
123     qemu_log_mask(CPU_LOG_MMU, "mmu=%d miss v=%" VADDR_PRIx "\n",
124                   mmu_idx, address);
125 
126     env->ear = address;
127     switch (lu.err) {
128     case ERR_PROT:
129         env->esr = access_type == MMU_INST_FETCH ? 17 : 16;
130         env->esr |= (access_type == MMU_DATA_STORE) << 10;
131         break;
132     case ERR_MISS:
133         env->esr = access_type == MMU_INST_FETCH ? 19 : 18;
134         env->esr |= (access_type == MMU_DATA_STORE) << 10;
135         break;
136     default:
137         abort();
138     }
139 
140     if (cs->exception_index == EXCP_MMU) {
141         cpu_abort(cs, "recursive faults\n");
142     }
143 
144     /* TLB miss.  */
145     cs->exception_index = EXCP_MMU;
146     cpu_loop_exit_restore(cs, retaddr);
147 }
148 
mb_cpu_do_interrupt(CPUState * cs)149 void mb_cpu_do_interrupt(CPUState *cs)
150 {
151     MicroBlazeCPU *cpu = MICROBLAZE_CPU(cs);
152     CPUMBState *env = &cpu->env;
153     uint32_t t, msr = mb_cpu_read_msr(env);
154     bool set_esr;
155 
156     /* IMM flag cannot propagate across a branch and into the dslot.  */
157     assert((env->iflags & (D_FLAG | IMM_FLAG)) != (D_FLAG | IMM_FLAG));
158     /* BIMM flag cannot be set without D_FLAG. */
159     assert((env->iflags & (D_FLAG | BIMM_FLAG)) != BIMM_FLAG);
160     /* RTI flags are private to translate. */
161     assert(!(env->iflags & (DRTI_FLAG | DRTE_FLAG | DRTB_FLAG)));
162 
163     switch (cs->exception_index) {
164     case EXCP_HW_EXCP:
165         if (!(cpu->cfg.pvr_regs[0] & PVR0_USE_EXC_MASK)) {
166             qemu_log_mask(LOG_GUEST_ERROR,
167                           "Exception raised on system without exceptions!\n");
168             return;
169         }
170 
171         qemu_log_mask(CPU_LOG_INT,
172                       "INT: HWE at pc=%08x msr=%08x iflags=%x\n",
173                       env->pc, msr, env->iflags);
174 
175         /* Exception breaks branch + dslot sequence?  */
176         set_esr = true;
177         env->esr &= ~D_FLAG;
178         if (env->iflags & D_FLAG) {
179             env->esr |= D_FLAG;
180             env->btr = env->btarget;
181         }
182 
183         /* Exception in progress. */
184         msr |= MSR_EIP;
185         env->regs[17] = env->pc + 4;
186         env->pc = cpu->cfg.base_vectors + 0x20;
187         break;
188 
189     case EXCP_MMU:
190         qemu_log_mask(CPU_LOG_INT,
191                       "INT: MMU at pc=%08x msr=%08x "
192                       "ear=%" PRIx64 " iflags=%x\n",
193                       env->pc, msr, env->ear, env->iflags);
194 
195         /* Exception breaks branch + dslot sequence? */
196         set_esr = true;
197         env->esr &= ~D_FLAG;
198         if (env->iflags & D_FLAG) {
199             env->esr |= D_FLAG;
200             env->btr = env->btarget;
201             /* Reexecute the branch. */
202             env->regs[17] = env->pc - (env->iflags & BIMM_FLAG ? 8 : 4);
203         } else if (env->iflags & IMM_FLAG) {
204             /* Reexecute the imm. */
205             env->regs[17] = env->pc - 4;
206         } else {
207             env->regs[17] = env->pc;
208         }
209 
210         /* Exception in progress. */
211         msr |= MSR_EIP;
212         env->pc = cpu->cfg.base_vectors + 0x20;
213         break;
214 
215     case EXCP_IRQ:
216         assert(!(msr & (MSR_EIP | MSR_BIP)));
217         assert(msr & MSR_IE);
218         assert(!(env->iflags & (D_FLAG | IMM_FLAG)));
219 
220         qemu_log_mask(CPU_LOG_INT,
221                       "INT: DEV at pc=%08x msr=%08x iflags=%x\n",
222                       env->pc, msr, env->iflags);
223         set_esr = false;
224 
225         /* Disable interrupts.  */
226         msr &= ~MSR_IE;
227         env->regs[14] = env->pc;
228         env->pc = cpu->cfg.base_vectors + 0x10;
229         break;
230 
231     case EXCP_HW_BREAK:
232         assert(!(env->iflags & (D_FLAG | IMM_FLAG)));
233 
234         qemu_log_mask(CPU_LOG_INT,
235                       "INT: BRK at pc=%08x msr=%08x iflags=%x\n",
236                       env->pc, msr, env->iflags);
237         set_esr = false;
238 
239         /* Break in progress. */
240         msr |= MSR_BIP;
241         env->regs[16] = env->pc;
242         env->pc = cpu->cfg.base_vectors + 0x18;
243         break;
244 
245     default:
246         cpu_abort(cs, "unhandled exception type=%d\n", cs->exception_index);
247         /* not reached */
248     }
249 
250     /* Save previous mode, disable mmu, disable user-mode. */
251     t = (msr & (MSR_VM | MSR_UM)) << 1;
252     msr &= ~(MSR_VMS | MSR_UMS | MSR_VM | MSR_UM);
253     msr |= t;
254     mb_cpu_write_msr(env, msr);
255 
256     env->res_addr = RES_ADDR_NONE;
257     env->iflags = 0;
258 
259     if (!set_esr) {
260         qemu_log_mask(CPU_LOG_INT,
261                       "         to pc=%08x msr=%08x\n", env->pc, msr);
262     } else if (env->esr & D_FLAG) {
263         qemu_log_mask(CPU_LOG_INT,
264                       "         to pc=%08x msr=%08x esr=%04x btr=%08x\n",
265                       env->pc, msr, env->esr, env->btr);
266     } else {
267         qemu_log_mask(CPU_LOG_INT,
268                       "         to pc=%08x msr=%08x esr=%04x\n",
269                       env->pc, msr, env->esr);
270     }
271 }
272 
mb_cpu_get_phys_page_attrs_debug(CPUState * cs,vaddr addr,MemTxAttrs * attrs)273 hwaddr mb_cpu_get_phys_page_attrs_debug(CPUState *cs, vaddr addr,
274                                         MemTxAttrs *attrs)
275 {
276     MicroBlazeCPU *cpu = MICROBLAZE_CPU(cs);
277     target_ulong vaddr, paddr = 0;
278     MicroBlazeMMULookup lu;
279     int mmu_idx = cpu_mmu_index(cs, false);
280     unsigned int hit;
281 
282     /* Caller doesn't initialize */
283     *attrs = (MemTxAttrs) {};
284     attrs->secure = mb_cpu_access_is_secure(cpu, MMU_DATA_LOAD);
285 
286     if (mmu_idx != MMU_NOMMU_IDX) {
287         hit = mmu_translate(cpu, &lu, addr, 0, 0);
288         if (hit) {
289             vaddr = addr & TARGET_PAGE_MASK;
290             paddr = lu.paddr + vaddr - lu.vaddr;
291         } else
292             paddr = 0; /* ???.  */
293     } else
294         paddr = addr & TARGET_PAGE_MASK;
295 
296     return paddr;
297 }
298 
mb_cpu_exec_interrupt(CPUState * cs,int interrupt_request)299 bool mb_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
300 {
301     CPUMBState *env = cpu_env(cs);
302 
303     if ((interrupt_request & CPU_INTERRUPT_HARD)
304         && (env->msr & MSR_IE)
305         && !(env->msr & (MSR_EIP | MSR_BIP))
306         && !(env->iflags & (D_FLAG | IMM_FLAG))) {
307         cs->exception_index = EXCP_IRQ;
308         mb_cpu_do_interrupt(cs);
309         return true;
310     }
311     return false;
312 }
313 
314 #endif /* !CONFIG_USER_ONLY */
315