xref: /openbmc/qemu/target/ppc/mem_helper.c (revision dc5bd18f)
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 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 #include "qemu/osdep.h"
20 #include "cpu.h"
21 #include "exec/exec-all.h"
22 #include "qemu/host-utils.h"
23 #include "exec/helper-proto.h"
24 
25 #include "helper_regs.h"
26 #include "exec/cpu_ldst.h"
27 #include "internal.h"
28 
29 //#define DEBUG_OP
30 
31 static inline bool needs_byteswap(const CPUPPCState *env)
32 {
33 #if defined(TARGET_WORDS_BIGENDIAN)
34   return msr_le;
35 #else
36   return !msr_le;
37 #endif
38 }
39 
40 /*****************************************************************************/
41 /* Memory load and stores */
42 
43 static inline target_ulong addr_add(CPUPPCState *env, target_ulong addr,
44                                     target_long arg)
45 {
46 #if defined(TARGET_PPC64)
47     if (!msr_is_64bit(env, env->msr)) {
48         return (uint32_t)(addr + arg);
49     } else
50 #endif
51     {
52         return addr + arg;
53     }
54 }
55 
56 void helper_lmw(CPUPPCState *env, target_ulong addr, uint32_t reg)
57 {
58     for (; reg < 32; reg++) {
59         if (needs_byteswap(env)) {
60             env->gpr[reg] = bswap32(cpu_ldl_data_ra(env, addr, GETPC()));
61         } else {
62             env->gpr[reg] = cpu_ldl_data_ra(env, addr, GETPC());
63         }
64         addr = addr_add(env, addr, 4);
65     }
66 }
67 
68 void helper_stmw(CPUPPCState *env, target_ulong addr, uint32_t reg)
69 {
70     for (; reg < 32; reg++) {
71         if (needs_byteswap(env)) {
72             cpu_stl_data_ra(env, addr, bswap32((uint32_t)env->gpr[reg]),
73                                                    GETPC());
74         } else {
75             cpu_stl_data_ra(env, addr, (uint32_t)env->gpr[reg], GETPC());
76         }
77         addr = addr_add(env, addr, 4);
78     }
79 }
80 
81 static void do_lsw(CPUPPCState *env, target_ulong addr, uint32_t nb,
82                    uint32_t reg, uintptr_t raddr)
83 {
84     int sh;
85 
86     for (; nb > 3; nb -= 4) {
87         env->gpr[reg] = cpu_ldl_data_ra(env, addr, raddr);
88         reg = (reg + 1) % 32;
89         addr = addr_add(env, addr, 4);
90     }
91     if (unlikely(nb > 0)) {
92         env->gpr[reg] = 0;
93         for (sh = 24; nb > 0; nb--, sh -= 8) {
94             env->gpr[reg] |= cpu_ldub_data_ra(env, addr, raddr) << sh;
95             addr = addr_add(env, addr, 1);
96         }
97     }
98 }
99 
100 void helper_lsw(CPUPPCState *env, target_ulong addr, uint32_t nb, uint32_t reg)
101 {
102     do_lsw(env, addr, nb, reg, GETPC());
103 }
104 
105 /* PPC32 specification says we must generate an exception if
106  * rA is in the range of registers to be loaded.
107  * In an other hand, IBM says this is valid, but rA won't be loaded.
108  * For now, I'll follow the spec...
109  */
110 void helper_lswx(CPUPPCState *env, target_ulong addr, uint32_t reg,
111                  uint32_t ra, uint32_t rb)
112 {
113     if (likely(xer_bc != 0)) {
114         int num_used_regs = DIV_ROUND_UP(xer_bc, 4);
115         if (unlikely((ra != 0 && lsw_reg_in_range(reg, num_used_regs, ra)) ||
116                      lsw_reg_in_range(reg, num_used_regs, rb))) {
117             raise_exception_err_ra(env, POWERPC_EXCP_PROGRAM,
118                                    POWERPC_EXCP_INVAL |
119                                    POWERPC_EXCP_INVAL_LSWX, GETPC());
120         } else {
121             do_lsw(env, addr, xer_bc, reg, GETPC());
122         }
123     }
124 }
125 
126 void helper_stsw(CPUPPCState *env, target_ulong addr, uint32_t nb,
127                  uint32_t reg)
128 {
129     int sh;
130 
131     for (; nb > 3; nb -= 4) {
132         cpu_stl_data_ra(env, addr, env->gpr[reg], GETPC());
133         reg = (reg + 1) % 32;
134         addr = addr_add(env, addr, 4);
135     }
136     if (unlikely(nb > 0)) {
137         for (sh = 24; nb > 0; nb--, sh -= 8) {
138             cpu_stb_data_ra(env, addr, (env->gpr[reg] >> sh) & 0xFF, GETPC());
139             addr = addr_add(env, addr, 1);
140         }
141     }
142 }
143 
144 void helper_dcbz(CPUPPCState *env, target_ulong addr, uint32_t opcode)
145 {
146     target_ulong mask, dcbz_size = env->dcache_line_size;
147     uint32_t i;
148     void *haddr;
149 
150 #if defined(TARGET_PPC64)
151     /* Check for dcbz vs dcbzl on 970 */
152     if (env->excp_model == POWERPC_EXCP_970 &&
153         !(opcode & 0x00200000) && ((env->spr[SPR_970_HID5] >> 7) & 0x3) == 1) {
154         dcbz_size = 32;
155     }
156 #endif
157 
158     /* Align address */
159     mask = ~(dcbz_size - 1);
160     addr &= mask;
161 
162     /* Check reservation */
163     if ((env->reserve_addr & mask) == (addr & mask))  {
164         env->reserve_addr = (target_ulong)-1ULL;
165     }
166 
167     /* Try fast path translate */
168     haddr = tlb_vaddr_to_host(env, addr, MMU_DATA_STORE, env->dmmu_idx);
169     if (haddr) {
170         memset(haddr, 0, dcbz_size);
171     } else {
172         /* Slow path */
173         for (i = 0; i < dcbz_size; i += 8) {
174             cpu_stq_data_ra(env, addr + i, 0, GETPC());
175         }
176     }
177 }
178 
179 void helper_icbi(CPUPPCState *env, target_ulong addr)
180 {
181     addr &= ~(env->dcache_line_size - 1);
182     /* Invalidate one cache line :
183      * PowerPC specification says this is to be treated like a load
184      * (not a fetch) by the MMU. To be sure it will be so,
185      * do the load "by hand".
186      */
187     cpu_ldl_data_ra(env, addr, GETPC());
188 }
189 
190 /* XXX: to be tested */
191 target_ulong helper_lscbx(CPUPPCState *env, target_ulong addr, uint32_t reg,
192                           uint32_t ra, uint32_t rb)
193 {
194     int i, c, d;
195 
196     d = 24;
197     for (i = 0; i < xer_bc; i++) {
198         c = cpu_ldub_data_ra(env, addr, GETPC());
199         addr = addr_add(env, addr, 1);
200         /* ra (if not 0) and rb are never modified */
201         if (likely(reg != rb && (ra == 0 || reg != ra))) {
202             env->gpr[reg] = (env->gpr[reg] & ~(0xFF << d)) | (c << d);
203         }
204         if (unlikely(c == xer_cmp)) {
205             break;
206         }
207         if (likely(d != 0)) {
208             d -= 8;
209         } else {
210             d = 24;
211             reg++;
212             reg = reg & 0x1F;
213         }
214     }
215     return i;
216 }
217 
218 /*****************************************************************************/
219 /* Altivec extension helpers */
220 #if defined(HOST_WORDS_BIGENDIAN)
221 #define HI_IDX 0
222 #define LO_IDX 1
223 #else
224 #define HI_IDX 1
225 #define LO_IDX 0
226 #endif
227 
228 /* We use msr_le to determine index ordering in a vector.  However,
229    byteswapping is not simply controlled by msr_le.  We also need to take
230    into account endianness of the target.  This is done for the little-endian
231    PPC64 user-mode target. */
232 
233 #define LVE(name, access, swap, element)                        \
234     void helper_##name(CPUPPCState *env, ppc_avr_t *r,          \
235                        target_ulong addr)                       \
236     {                                                           \
237         size_t n_elems = ARRAY_SIZE(r->element);                \
238         int adjust = HI_IDX*(n_elems - 1);                      \
239         int sh = sizeof(r->element[0]) >> 1;                    \
240         int index = (addr & 0xf) >> sh;                         \
241         if (msr_le) {                                           \
242             index = n_elems - index - 1;                        \
243         }                                                       \
244                                                                 \
245         if (needs_byteswap(env)) {                              \
246             r->element[LO_IDX ? index : (adjust - index)] =     \
247                 swap(access(env, addr, GETPC()));               \
248         } else {                                                \
249             r->element[LO_IDX ? index : (adjust - index)] =     \
250                 access(env, addr, GETPC());                     \
251         }                                                       \
252     }
253 #define I(x) (x)
254 LVE(lvebx, cpu_ldub_data_ra, I, u8)
255 LVE(lvehx, cpu_lduw_data_ra, bswap16, u16)
256 LVE(lvewx, cpu_ldl_data_ra, bswap32, u32)
257 #undef I
258 #undef LVE
259 
260 #define STVE(name, access, swap, element)                               \
261     void helper_##name(CPUPPCState *env, ppc_avr_t *r,                  \
262                        target_ulong addr)                               \
263     {                                                                   \
264         size_t n_elems = ARRAY_SIZE(r->element);                        \
265         int adjust = HI_IDX * (n_elems - 1);                            \
266         int sh = sizeof(r->element[0]) >> 1;                            \
267         int index = (addr & 0xf) >> sh;                                 \
268         if (msr_le) {                                                   \
269             index = n_elems - index - 1;                                \
270         }                                                               \
271                                                                         \
272         if (needs_byteswap(env)) {                                      \
273             access(env, addr, swap(r->element[LO_IDX ? index :          \
274                                               (adjust - index)]),       \
275                         GETPC());                                       \
276         } else {                                                        \
277             access(env, addr, r->element[LO_IDX ? index :               \
278                                          (adjust - index)], GETPC());   \
279         }                                                               \
280     }
281 #define I(x) (x)
282 STVE(stvebx, cpu_stb_data_ra, I, u8)
283 STVE(stvehx, cpu_stw_data_ra, bswap16, u16)
284 STVE(stvewx, cpu_stl_data_ra, bswap32, u32)
285 #undef I
286 #undef LVE
287 
288 #ifdef TARGET_PPC64
289 #define GET_NB(rb) ((rb >> 56) & 0xFF)
290 
291 #define VSX_LXVL(name, lj)                                              \
292 void helper_##name(CPUPPCState *env, target_ulong addr,                 \
293                    target_ulong xt_num, target_ulong rb)                \
294 {                                                                       \
295     int i;                                                              \
296     ppc_vsr_t xt;                                                       \
297     uint64_t nb = GET_NB(rb);                                           \
298                                                                         \
299     xt.s128 = int128_zero();                                            \
300     if (nb) {                                                           \
301         nb = (nb >= 16) ? 16 : nb;                                      \
302         if (msr_le && !lj) {                                            \
303             for (i = 16; i > 16 - nb; i--) {                            \
304                 xt.VsrB(i - 1) = cpu_ldub_data_ra(env, addr, GETPC());  \
305                 addr = addr_add(env, addr, 1);                          \
306             }                                                           \
307         } else {                                                        \
308             for (i = 0; i < nb; i++) {                                  \
309                 xt.VsrB(i) = cpu_ldub_data_ra(env, addr, GETPC());      \
310                 addr = addr_add(env, addr, 1);                          \
311             }                                                           \
312         }                                                               \
313     }                                                                   \
314     putVSR(xt_num, &xt, env);                                           \
315 }
316 
317 VSX_LXVL(lxvl, 0)
318 VSX_LXVL(lxvll, 1)
319 #undef VSX_LXVL
320 
321 #define VSX_STXVL(name, lj)                                       \
322 void helper_##name(CPUPPCState *env, target_ulong addr,           \
323                    target_ulong xt_num, target_ulong rb)          \
324 {                                                                 \
325     int i;                                                        \
326     ppc_vsr_t xt;                                                 \
327     target_ulong nb = GET_NB(rb);                                 \
328                                                                   \
329     if (!nb) {                                                    \
330         return;                                                   \
331     }                                                             \
332     getVSR(xt_num, &xt, env);                                     \
333     nb = (nb >= 16) ? 16 : nb;                                    \
334     if (msr_le && !lj) {                                          \
335         for (i = 16; i > 16 - nb; i--) {                          \
336             cpu_stb_data_ra(env, addr, xt.VsrB(i - 1), GETPC());  \
337             addr = addr_add(env, addr, 1);                        \
338         }                                                         \
339     } else {                                                      \
340         for (i = 0; i < nb; i++) {                                \
341             cpu_stb_data_ra(env, addr, xt.VsrB(i), GETPC());      \
342             addr = addr_add(env, addr, 1);                        \
343         }                                                         \
344     }                                                             \
345 }
346 
347 VSX_STXVL(stxvl, 0)
348 VSX_STXVL(stxvll, 1)
349 #undef VSX_STXVL
350 #undef GET_NB
351 #endif /* TARGET_PPC64 */
352 
353 #undef HI_IDX
354 #undef LO_IDX
355 
356 void helper_tbegin(CPUPPCState *env)
357 {
358     /* As a degenerate implementation, always fail tbegin.  The reason
359      * given is "Nesting overflow".  The "persistent" bit is set,
360      * providing a hint to the error handler to not retry.  The TFIAR
361      * captures the address of the failure, which is this tbegin
362      * instruction.  Instruction execution will continue with the
363      * next instruction in memory, which is precisely what we want.
364      */
365 
366     env->spr[SPR_TEXASR] =
367         (1ULL << TEXASR_FAILURE_PERSISTENT) |
368         (1ULL << TEXASR_NESTING_OVERFLOW) |
369         (msr_hv << TEXASR_PRIVILEGE_HV) |
370         (msr_pr << TEXASR_PRIVILEGE_PR) |
371         (1ULL << TEXASR_FAILURE_SUMMARY) |
372         (1ULL << TEXASR_TFIAR_EXACT);
373     env->spr[SPR_TFIAR] = env->nip | (msr_hv << 1) | msr_pr;
374     env->spr[SPR_TFHAR] = env->nip + 4;
375     env->crf[0] = 0xB; /* 0b1010 = transaction failure */
376 }
377