xref: /qemu/target/ppc/mem_helper.c (revision 7cef6d686309e2792186504ae17cf4f3eb57ef68)
1 /*
2  *  PowerPC memory access emulation helpers for QEMU.
3  *
4  *  Copyright (c) 2003-2007 Jocelyn Mayer
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 "cpu.h"
22 #include "exec/target_page.h"
23 #include "qemu/host-utils.h"
24 #include "exec/helper-proto.h"
25 #include "helper_regs.h"
26 #include "accel/tcg/cpu-ldst.h"
27 #include "accel/tcg/helper-retaddr.h"
28 #include "accel/tcg/probe.h"
29 #include "internal.h"
30 #include "qemu/atomic128.h"
31 
32 /* #define DEBUG_OP */
33 
needs_byteswap(const CPUPPCState * env)34 static inline bool needs_byteswap(const CPUPPCState *env)
35 {
36 #if TARGET_BIG_ENDIAN
37   return FIELD_EX64(env->msr, MSR, LE);
38 #else
39   return !FIELD_EX64(env->msr, MSR, LE);
40 #endif
41 }
42 
43 /*****************************************************************************/
44 /* Memory load and stores */
45 
addr_add(CPUPPCState * env,target_ulong addr,target_long arg)46 static inline target_ulong addr_add(CPUPPCState *env, target_ulong addr,
47                                     target_long arg)
48 {
49 #if defined(TARGET_PPC64)
50     if (!msr_is_64bit(env, env->msr)) {
51         return (uint32_t)(addr + arg);
52     } else
53 #endif
54     {
55         return addr + arg;
56     }
57 }
58 
probe_contiguous(CPUPPCState * env,target_ulong addr,uint32_t nb,MMUAccessType access_type,int mmu_idx,uintptr_t raddr)59 static void *probe_contiguous(CPUPPCState *env, target_ulong addr, uint32_t nb,
60                               MMUAccessType access_type, int mmu_idx,
61                               uintptr_t raddr)
62 {
63     void *host1, *host2;
64     uint32_t nb_pg1, nb_pg2;
65 
66     nb_pg1 = -(addr | TARGET_PAGE_MASK);
67     if (likely(nb <= nb_pg1)) {
68         /* The entire operation is on a single page.  */
69         return probe_access(env, addr, nb, access_type, mmu_idx, raddr);
70     }
71 
72     /* The operation spans two pages.  */
73     nb_pg2 = nb - nb_pg1;
74     host1 = probe_access(env, addr, nb_pg1, access_type, mmu_idx, raddr);
75     addr = addr_add(env, addr, nb_pg1);
76     host2 = probe_access(env, addr, nb_pg2, access_type, mmu_idx, raddr);
77 
78     /* If the two host pages are contiguous, optimize.  */
79     if (host2 == host1 + nb_pg1) {
80         return host1;
81     }
82     return NULL;
83 }
84 
helper_lmw(CPUPPCState * env,target_ulong addr,uint32_t reg)85 void helper_lmw(CPUPPCState *env, target_ulong addr, uint32_t reg)
86 {
87     uintptr_t raddr = GETPC();
88     int mmu_idx = ppc_env_mmu_index(env, false);
89     void *host = probe_contiguous(env, addr, (32 - reg) * 4,
90                                   MMU_DATA_LOAD, mmu_idx, raddr);
91 
92     if (likely(host)) {
93         /* Fast path -- the entire operation is in RAM at host.  */
94         for (; reg < 32; reg++) {
95             env->gpr[reg] = (uint32_t)ldl_be_p(host);
96             host += 4;
97         }
98     } else {
99         /* Slow path -- at least some of the operation requires i/o.  */
100         for (; reg < 32; reg++) {
101             env->gpr[reg] = cpu_ldl_mmuidx_ra(env, addr, mmu_idx, raddr);
102             addr = addr_add(env, addr, 4);
103         }
104     }
105 }
106 
helper_stmw(CPUPPCState * env,target_ulong addr,uint32_t reg)107 void helper_stmw(CPUPPCState *env, target_ulong addr, uint32_t reg)
108 {
109     uintptr_t raddr = GETPC();
110     int mmu_idx = ppc_env_mmu_index(env, false);
111     void *host = probe_contiguous(env, addr, (32 - reg) * 4,
112                                   MMU_DATA_STORE, mmu_idx, raddr);
113 
114     if (likely(host)) {
115         /* Fast path -- the entire operation is in RAM at host.  */
116         for (; reg < 32; reg++) {
117             stl_be_p(host, env->gpr[reg]);
118             host += 4;
119         }
120     } else {
121         /* Slow path -- at least some of the operation requires i/o.  */
122         for (; reg < 32; reg++) {
123             cpu_stl_mmuidx_ra(env, addr, env->gpr[reg], mmu_idx, raddr);
124             addr = addr_add(env, addr, 4);
125         }
126     }
127 }
128 
do_lsw(CPUPPCState * env,target_ulong addr,uint32_t nb,uint32_t reg,uintptr_t raddr)129 static void do_lsw(CPUPPCState *env, target_ulong addr, uint32_t nb,
130                    uint32_t reg, uintptr_t raddr)
131 {
132     int mmu_idx;
133     void *host;
134     uint32_t val;
135 
136     if (unlikely(nb == 0)) {
137         return;
138     }
139 
140     mmu_idx = ppc_env_mmu_index(env, false);
141     host = probe_contiguous(env, addr, nb, MMU_DATA_LOAD, mmu_idx, raddr);
142 
143     if (likely(host)) {
144         /* Fast path -- the entire operation is in RAM at host.  */
145         for (; nb > 3; nb -= 4) {
146             env->gpr[reg] = (uint32_t)ldl_be_p(host);
147             reg = (reg + 1) % 32;
148             host += 4;
149         }
150         switch (nb) {
151         default:
152             return;
153         case 1:
154             val = ldub_p(host) << 24;
155             break;
156         case 2:
157             val = lduw_be_p(host) << 16;
158             break;
159         case 3:
160             val = (lduw_be_p(host) << 16) | (ldub_p(host + 2) << 8);
161             break;
162         }
163     } else {
164         /* Slow path -- at least some of the operation requires i/o.  */
165         for (; nb > 3; nb -= 4) {
166             env->gpr[reg] = cpu_ldl_mmuidx_ra(env, addr, mmu_idx, raddr);
167             reg = (reg + 1) % 32;
168             addr = addr_add(env, addr, 4);
169         }
170         switch (nb) {
171         default:
172             return;
173         case 1:
174             val = cpu_ldub_mmuidx_ra(env, addr, mmu_idx, raddr) << 24;
175             break;
176         case 2:
177             val = cpu_lduw_mmuidx_ra(env, addr, mmu_idx, raddr) << 16;
178             break;
179         case 3:
180             val = cpu_lduw_mmuidx_ra(env, addr, mmu_idx, raddr) << 16;
181             addr = addr_add(env, addr, 2);
182             val |= cpu_ldub_mmuidx_ra(env, addr, mmu_idx, raddr) << 8;
183             break;
184         }
185     }
186     env->gpr[reg] = val;
187 }
188 
helper_lsw(CPUPPCState * env,target_ulong addr,uint32_t nb,uint32_t reg)189 void helper_lsw(CPUPPCState *env, target_ulong addr,
190                 uint32_t nb, uint32_t reg)
191 {
192     do_lsw(env, addr, nb, reg, GETPC());
193 }
194 
195 /*
196  * PPC32 specification says we must generate an exception if rA is in
197  * the range of registers to be loaded.  In an other hand, IBM says
198  * this is valid, but rA won't be loaded.  For now, I'll follow the
199  * spec...
200  */
helper_lswx(CPUPPCState * env,target_ulong addr,uint32_t reg,uint32_t ra,uint32_t rb)201 void helper_lswx(CPUPPCState *env, target_ulong addr, uint32_t reg,
202                  uint32_t ra, uint32_t rb)
203 {
204     if (likely(xer_bc != 0)) {
205         int num_used_regs = DIV_ROUND_UP(xer_bc, 4);
206         if (unlikely((ra != 0 && lsw_reg_in_range(reg, num_used_regs, ra)) ||
207                      lsw_reg_in_range(reg, num_used_regs, rb))) {
208             raise_exception_err_ra(env, POWERPC_EXCP_PROGRAM,
209                                    POWERPC_EXCP_INVAL |
210                                    POWERPC_EXCP_INVAL_LSWX, GETPC());
211         } else {
212             do_lsw(env, addr, xer_bc, reg, GETPC());
213         }
214     }
215 }
216 
helper_stsw(CPUPPCState * env,target_ulong addr,uint32_t nb,uint32_t reg)217 void helper_stsw(CPUPPCState *env, target_ulong addr, uint32_t nb,
218                  uint32_t reg)
219 {
220     uintptr_t raddr = GETPC();
221     int mmu_idx;
222     void *host;
223     uint32_t val;
224 
225     if (unlikely(nb == 0)) {
226         return;
227     }
228 
229     mmu_idx = ppc_env_mmu_index(env, false);
230     host = probe_contiguous(env, addr, nb, MMU_DATA_STORE, mmu_idx, raddr);
231 
232     if (likely(host)) {
233         /* Fast path -- the entire operation is in RAM at host.  */
234         for (; nb > 3; nb -= 4) {
235             stl_be_p(host, env->gpr[reg]);
236             reg = (reg + 1) % 32;
237             host += 4;
238         }
239         val = env->gpr[reg];
240         switch (nb) {
241         case 1:
242             stb_p(host, val >> 24);
243             break;
244         case 2:
245             stw_be_p(host, val >> 16);
246             break;
247         case 3:
248             stw_be_p(host, val >> 16);
249             stb_p(host + 2, val >> 8);
250             break;
251         }
252     } else {
253         for (; nb > 3; nb -= 4) {
254             cpu_stl_mmuidx_ra(env, addr, env->gpr[reg], mmu_idx, raddr);
255             reg = (reg + 1) % 32;
256             addr = addr_add(env, addr, 4);
257         }
258         val = env->gpr[reg];
259         switch (nb) {
260         case 1:
261             cpu_stb_mmuidx_ra(env, addr, val >> 24, mmu_idx, raddr);
262             break;
263         case 2:
264             cpu_stw_mmuidx_ra(env, addr, val >> 16, mmu_idx, raddr);
265             break;
266         case 3:
267             cpu_stw_mmuidx_ra(env, addr, val >> 16, mmu_idx, raddr);
268             addr = addr_add(env, addr, 2);
269             cpu_stb_mmuidx_ra(env, addr, val >> 8, mmu_idx, raddr);
270             break;
271         }
272     }
273 }
274 
dcbz_common(CPUPPCState * env,target_ulong addr,int mmu_idx,int dcbz_size,uintptr_t retaddr)275 static void dcbz_common(CPUPPCState *env, target_ulong addr,
276                         int mmu_idx, int dcbz_size, uintptr_t retaddr)
277 {
278     target_ulong mask = ~(target_ulong)(dcbz_size - 1);
279     void *haddr;
280 
281     /* Align address */
282     addr &= mask;
283 
284     /* Check reservation */
285     if (unlikely((env->reserve_addr & mask) == addr))  {
286         env->reserve_addr = (target_ulong)-1ULL;
287     }
288 
289     /* Try fast path translate */
290 #ifdef CONFIG_USER_ONLY
291     haddr = tlb_vaddr_to_host(env, addr, MMU_DATA_STORE, mmu_idx);
292 #else
293     haddr = probe_write(env, addr, dcbz_size, mmu_idx, retaddr);
294     if (unlikely(!haddr)) {
295         /* Slow path */
296         for (int i = 0; i < dcbz_size; i += 8) {
297             cpu_stq_mmuidx_ra(env, addr + i, 0, mmu_idx, retaddr);
298         }
299         return;
300     }
301 #endif
302 
303     set_helper_retaddr(retaddr);
304     memset(haddr, 0, dcbz_size);
305     clear_helper_retaddr();
306 }
307 
helper_dcbz(CPUPPCState * env,target_ulong addr,int mmu_idx)308 void helper_dcbz(CPUPPCState *env, target_ulong addr, int mmu_idx)
309 {
310     dcbz_common(env, addr, mmu_idx, env->dcache_line_size, GETPC());
311 }
312 
313 #ifdef TARGET_PPC64
helper_dcbzl(CPUPPCState * env,target_ulong addr)314 void helper_dcbzl(CPUPPCState *env, target_ulong addr)
315 {
316     int dcbz_size = env->dcache_line_size;
317 
318     /*
319      * The translator checked for POWERPC_EXCP_970.
320      * All that's left is to check HID5.
321      */
322     if (((env->spr[SPR_970_HID5] >> 7) & 0x3) == 1) {
323         dcbz_size = 32;
324     }
325 
326     dcbz_common(env, addr, ppc_env_mmu_index(env, false), dcbz_size, GETPC());
327 }
328 #endif
329 
helper_icbi(CPUPPCState * env,target_ulong addr)330 void helper_icbi(CPUPPCState *env, target_ulong addr)
331 {
332     addr &= ~(env->dcache_line_size - 1);
333     /*
334      * Invalidate one cache line :
335      * PowerPC specification says this is to be treated like a load
336      * (not a fetch) by the MMU. To be sure it will be so,
337      * do the load "by hand".
338      */
339     cpu_ldl_data_ra(env, addr, GETPC());
340 }
341 
helper_icbiep(CPUPPCState * env,target_ulong addr)342 void helper_icbiep(CPUPPCState *env, target_ulong addr)
343 {
344 #if !defined(CONFIG_USER_ONLY)
345     /* See comments above */
346     addr &= ~(env->dcache_line_size - 1);
347     cpu_ldl_mmuidx_ra(env, addr, PPC_TLB_EPID_LOAD, GETPC());
348 #endif
349 }
350 
351 /* XXX: to be tested */
helper_lscbx(CPUPPCState * env,target_ulong addr,uint32_t reg,uint32_t ra,uint32_t rb)352 target_ulong helper_lscbx(CPUPPCState *env, target_ulong addr, uint32_t reg,
353                           uint32_t ra, uint32_t rb)
354 {
355     int i, c, d;
356 
357     d = 24;
358     for (i = 0; i < xer_bc; i++) {
359         c = cpu_ldub_data_ra(env, addr, GETPC());
360         addr = addr_add(env, addr, 1);
361         /* ra (if not 0) and rb are never modified */
362         if (likely(reg != rb && (ra == 0 || reg != ra))) {
363             env->gpr[reg] = (env->gpr[reg] & ~(0xFF << d)) | (c << d);
364         }
365         if (unlikely(c == xer_cmp)) {
366             break;
367         }
368         if (likely(d != 0)) {
369             d -= 8;
370         } else {
371             d = 24;
372             reg++;
373             reg = reg & 0x1F;
374         }
375     }
376     return i;
377 }
378 
379 /*****************************************************************************/
380 /* Altivec extension helpers */
381 #if HOST_BIG_ENDIAN
382 #define HI_IDX 0
383 #define LO_IDX 1
384 #else
385 #define HI_IDX 1
386 #define LO_IDX 0
387 #endif
388 
389 /*
390  * We use MSR_LE to determine index ordering in a vector.  However,
391  * byteswapping is not simply controlled by MSR_LE.  We also need to
392  * take into account endianness of the target.  This is done for the
393  * little-endian PPC64 user-mode target.
394  */
395 
396 #define LVE(name, access, swap, element)                        \
397     void helper_##name(CPUPPCState *env, ppc_avr_t *r,          \
398                        target_ulong addr)                       \
399     {                                                           \
400         size_t n_elems = ARRAY_SIZE(r->element);                \
401         int adjust = HI_IDX * (n_elems - 1);                    \
402         int sh = sizeof(r->element[0]) >> 1;                    \
403         int index = (addr & 0xf) >> sh;                         \
404         if (FIELD_EX64(env->msr, MSR, LE)) {                    \
405             index = n_elems - index - 1;                        \
406         }                                                       \
407                                                                 \
408         if (needs_byteswap(env)) {                              \
409             r->element[LO_IDX ? index : (adjust - index)] =     \
410                 swap(access(env, addr, GETPC()));               \
411         } else {                                                \
412             r->element[LO_IDX ? index : (adjust - index)] =     \
413                 access(env, addr, GETPC());                     \
414         }                                                       \
415     }
416 #define I(x) (x)
LVE(LVEBX,cpu_ldub_data_ra,I,u8)417 LVE(LVEBX, cpu_ldub_data_ra, I, u8)
418 LVE(LVEHX, cpu_lduw_data_ra, bswap16, u16)
419 LVE(LVEWX, cpu_ldl_data_ra, bswap32, u32)
420 #undef I
421 #undef LVE
422 
423 #define STVE(name, access, swap, element)                               \
424     void helper_##name(CPUPPCState *env, ppc_avr_t *r,                  \
425                        target_ulong addr)                               \
426     {                                                                   \
427         size_t n_elems = ARRAY_SIZE(r->element);                        \
428         int adjust = HI_IDX * (n_elems - 1);                            \
429         int sh = sizeof(r->element[0]) >> 1;                            \
430         int index = (addr & 0xf) >> sh;                                 \
431         if (FIELD_EX64(env->msr, MSR, LE)) {                            \
432             index = n_elems - index - 1;                                \
433         }                                                               \
434                                                                         \
435         if (needs_byteswap(env)) {                                      \
436             access(env, addr, swap(r->element[LO_IDX ? index :          \
437                                               (adjust - index)]),       \
438                         GETPC());                                       \
439         } else {                                                        \
440             access(env, addr, r->element[LO_IDX ? index :               \
441                                          (adjust - index)], GETPC());   \
442         }                                                               \
443     }
444 #define I(x) (x)
445 STVE(STVEBX, cpu_stb_data_ra, I, u8)
446 STVE(STVEHX, cpu_stw_data_ra, bswap16, u16)
447 STVE(STVEWX, cpu_stl_data_ra, bswap32, u32)
448 #undef I
449 #undef LVE
450 
451 #ifdef TARGET_PPC64
452 #define GET_NB(rb) ((rb >> 56) & 0xFF)
453 
454 #define VSX_LXVL(name, lj)                                              \
455 void helper_##name(CPUPPCState *env, target_ulong addr,                 \
456                    ppc_vsr_t *xt, target_ulong rb)                      \
457 {                                                                       \
458     ppc_vsr_t t;                                                        \
459     uint64_t nb = GET_NB(rb);                                           \
460     int i;                                                              \
461                                                                         \
462     t.s128 = int128_zero();                                             \
463     if (nb) {                                                           \
464         nb = (nb >= 16) ? 16 : nb;                                      \
465         if (FIELD_EX64(env->msr, MSR, LE) && !lj) {                     \
466             for (i = 16; i > 16 - nb; i--) {                            \
467                 t.VsrB(i - 1) = cpu_ldub_data_ra(env, addr, GETPC());   \
468                 addr = addr_add(env, addr, 1);                          \
469             }                                                           \
470         } else {                                                        \
471             for (i = 0; i < nb; i++) {                                  \
472                 t.VsrB(i) = cpu_ldub_data_ra(env, addr, GETPC());       \
473                 addr = addr_add(env, addr, 1);                          \
474             }                                                           \
475         }                                                               \
476     }                                                                   \
477     *xt = t;                                                            \
478 }
479 
480 VSX_LXVL(LXVL, 0)
481 VSX_LXVL(LXVLL, 1)
482 #undef VSX_LXVL
483 
484 #define VSX_STXVL(name, lj)                                       \
485 void helper_##name(CPUPPCState *env, target_ulong addr,           \
486                    ppc_vsr_t *xt, target_ulong rb)                \
487 {                                                                 \
488     target_ulong nb = GET_NB(rb);                                 \
489     int i;                                                        \
490                                                                   \
491     if (!nb) {                                                    \
492         return;                                                   \
493     }                                                             \
494                                                                   \
495     nb = (nb >= 16) ? 16 : nb;                                    \
496     if (FIELD_EX64(env->msr, MSR, LE) && !lj) {                   \
497         for (i = 16; i > 16 - nb; i--) {                          \
498             cpu_stb_data_ra(env, addr, xt->VsrB(i - 1), GETPC()); \
499             addr = addr_add(env, addr, 1);                        \
500         }                                                         \
501     } else {                                                      \
502         for (i = 0; i < nb; i++) {                                \
503             cpu_stb_data_ra(env, addr, xt->VsrB(i), GETPC());     \
504             addr = addr_add(env, addr, 1);                        \
505         }                                                         \
506     }                                                             \
507 }
508 
509 VSX_STXVL(STXVL, 0)
510 VSX_STXVL(STXVLL, 1)
511 #undef VSX_STXVL
512 #undef GET_NB
513 #endif /* TARGET_PPC64 */
514 
515 #undef HI_IDX
516 #undef LO_IDX
517 
518 void helper_tbegin(CPUPPCState *env)
519 {
520     /*
521      * As a degenerate implementation, always fail tbegin.  The reason
522      * given is "Nesting overflow".  The "persistent" bit is set,
523      * providing a hint to the error handler to not retry.  The TFIAR
524      * captures the address of the failure, which is this tbegin
525      * instruction.  Instruction execution will continue with the next
526      * instruction in memory, which is precisely what we want.
527      */
528 
529     env->spr[SPR_TEXASR] =
530         (1ULL << TEXASR_FAILURE_PERSISTENT) |
531         (1ULL << TEXASR_NESTING_OVERFLOW) |
532         (FIELD_EX64_HV(env->msr) << TEXASR_PRIVILEGE_HV) |
533         (FIELD_EX64(env->msr, MSR, PR) << TEXASR_PRIVILEGE_PR) |
534         (1ULL << TEXASR_FAILURE_SUMMARY) |
535         (1ULL << TEXASR_TFIAR_EXACT);
536     env->spr[SPR_TFIAR] = env->nip | (FIELD_EX64_HV(env->msr) << 1) |
537                           FIELD_EX64(env->msr, MSR, PR);
538     env->spr[SPR_TFHAR] = env->nip + 4;
539     env->crf[0] = 0xB; /* 0b1010 = transaction failure */
540 }
541