xref: /openbmc/qemu/target/ppc/helper_regs.h (revision 2a53cff4)
1 /*
2  *  PowerPC emulation special registers manipulation 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 
20 #ifndef HELPER_REGS_H
21 #define HELPER_REGS_H
22 
23 #include "qemu/main-loop.h"
24 #include "exec/exec-all.h"
25 
26 /* Swap temporary saved registers with GPRs */
27 static inline void hreg_swap_gpr_tgpr(CPUPPCState *env)
28 {
29     target_ulong tmp;
30 
31     tmp = env->gpr[0];
32     env->gpr[0] = env->tgpr[0];
33     env->tgpr[0] = tmp;
34     tmp = env->gpr[1];
35     env->gpr[1] = env->tgpr[1];
36     env->tgpr[1] = tmp;
37     tmp = env->gpr[2];
38     env->gpr[2] = env->tgpr[2];
39     env->tgpr[2] = tmp;
40     tmp = env->gpr[3];
41     env->gpr[3] = env->tgpr[3];
42     env->tgpr[3] = tmp;
43 }
44 
45 static inline void hreg_compute_mem_idx(CPUPPCState *env)
46 {
47     /* This is our encoding for server processors. The architecture
48      * specifies that there is no such thing as userspace with
49      * translation off, however it appears that MacOS does it and
50      * some 32-bit CPUs support it. Weird...
51      *
52      *   0 = Guest User space virtual mode
53      *   1 = Guest Kernel space virtual mode
54      *   2 = Guest User space real mode
55      *   3 = Guest Kernel space real mode
56      *   4 = HV User space virtual mode
57      *   5 = HV Kernel space virtual mode
58      *   6 = HV User space real mode
59      *   7 = HV Kernel space real mode
60      *
61      * For BookE, we need 8 MMU modes as follow:
62      *
63      *  0 = AS 0 HV User space
64      *  1 = AS 0 HV Kernel space
65      *  2 = AS 1 HV User space
66      *  3 = AS 1 HV Kernel space
67      *  4 = AS 0 Guest User space
68      *  5 = AS 0 Guest Kernel space
69      *  6 = AS 1 Guest User space
70      *  7 = AS 1 Guest Kernel space
71      */
72     if (env->mmu_model & POWERPC_MMU_BOOKE) {
73         env->immu_idx = env->dmmu_idx = msr_pr ? 0 : 1;
74         env->immu_idx += msr_is ? 2 : 0;
75         env->dmmu_idx += msr_ds ? 2 : 0;
76         env->immu_idx += msr_gs ? 4 : 0;
77         env->dmmu_idx += msr_gs ? 4 : 0;
78     } else {
79         env->immu_idx = env->dmmu_idx = msr_pr ? 0 : 1;
80         env->immu_idx += msr_ir ? 0 : 2;
81         env->dmmu_idx += msr_dr ? 0 : 2;
82         env->immu_idx += msr_hv ? 4 : 0;
83         env->dmmu_idx += msr_hv ? 4 : 0;
84     }
85 }
86 
87 static inline void hreg_compute_hflags(CPUPPCState *env)
88 {
89     target_ulong hflags_mask;
90 
91     /* We 'forget' FE0 & FE1: we'll never generate imprecise exceptions */
92     hflags_mask = (1 << MSR_VR) | (1 << MSR_AP) | (1 << MSR_SA) |
93         (1 << MSR_PR) | (1 << MSR_FP) | (1 << MSR_SE) | (1 << MSR_BE) |
94         (1 << MSR_LE) | (1 << MSR_VSX) | (1 << MSR_IR) | (1 << MSR_DR);
95     hflags_mask |= (1ULL << MSR_CM) | (1ULL << MSR_SF) | MSR_HVB;
96     hreg_compute_mem_idx(env);
97     env->hflags = env->msr & hflags_mask;
98     /* Merge with hflags coming from other registers */
99     env->hflags |= env->hflags_nmsr;
100 }
101 
102 static inline void cpu_interrupt_exittb(CPUState *cs)
103 {
104     if (!qemu_mutex_iothread_locked()) {
105         qemu_mutex_lock_iothread();
106         cpu_interrupt(cs, CPU_INTERRUPT_EXITTB);
107         qemu_mutex_unlock_iothread();
108     } else {
109         cpu_interrupt(cs, CPU_INTERRUPT_EXITTB);
110     }
111 }
112 
113 static inline int hreg_store_msr(CPUPPCState *env, target_ulong value,
114                                  int alter_hv)
115 {
116     int excp;
117 #if !defined(CONFIG_USER_ONLY)
118     CPUState *cs = CPU(ppc_env_get_cpu(env));
119 #endif
120 
121     excp = 0;
122     value &= env->msr_mask;
123 #if !defined(CONFIG_USER_ONLY)
124     /* Neither mtmsr nor guest state can alter HV */
125     if (!alter_hv || !(env->msr & MSR_HVB)) {
126         value &= ~MSR_HVB;
127         value |= env->msr & MSR_HVB;
128     }
129     if (((value >> MSR_IR) & 1) != msr_ir ||
130         ((value >> MSR_DR) & 1) != msr_dr) {
131         cpu_interrupt_exittb(cs);
132     }
133     if ((env->mmu_model & POWERPC_MMU_BOOKE) &&
134         ((value >> MSR_GS) & 1) != msr_gs) {
135         cpu_interrupt_exittb(cs);
136     }
137     if (unlikely((env->flags & POWERPC_FLAG_TGPR) &&
138                  ((value ^ env->msr) & (1 << MSR_TGPR)))) {
139         /* Swap temporary saved registers with GPRs */
140         hreg_swap_gpr_tgpr(env);
141     }
142     if (unlikely((value >> MSR_EP) & 1) != msr_ep) {
143         /* Change the exception prefix on PowerPC 601 */
144         env->excp_prefix = ((value >> MSR_EP) & 1) * 0xFFF00000;
145     }
146     /* If PR=1 then EE, IR and DR must be 1
147      *
148      * Note: We only enforce this on 64-bit server processors.
149      * It appears that:
150      * - 32-bit implementations supports PR=1 and EE/DR/IR=0 and MacOS
151      *   exploits it.
152      * - 64-bit embedded implementations do not need any operation to be
153      *   performed when PR is set.
154      */
155     if ((env->insns_flags & PPC_SEGMENT_64B) && ((value >> MSR_PR) & 1)) {
156         value |= (1 << MSR_EE) | (1 << MSR_DR) | (1 << MSR_IR);
157     }
158 #endif
159     env->msr = value;
160     hreg_compute_hflags(env);
161 #if !defined(CONFIG_USER_ONLY)
162     if (unlikely(msr_pow == 1)) {
163         if (!env->pending_interrupts && (*env->check_pow)(env)) {
164             cs->halted = 1;
165             excp = EXCP_HALTED;
166         }
167     }
168 #endif
169 
170     return excp;
171 }
172 
173 #if !defined(CONFIG_USER_ONLY)
174 static inline void check_tlb_flush(CPUPPCState *env, bool global)
175 {
176     CPUState *cs = CPU(ppc_env_get_cpu(env));
177 
178     /* Handle global flushes first */
179     if (global && (env->tlb_need_flush & TLB_NEED_GLOBAL_FLUSH)) {
180         env->tlb_need_flush &= ~TLB_NEED_GLOBAL_FLUSH;
181         env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
182         tlb_flush_all_cpus_synced(cs);
183         return;
184     }
185 
186     /* Then handle local ones */
187     if (env->tlb_need_flush & TLB_NEED_LOCAL_FLUSH) {
188         env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
189         tlb_flush(cs);
190     }
191 }
192 #else
193 static inline void check_tlb_flush(CPUPPCState *env, bool global) { }
194 #endif
195 
196 #endif /* HELPER_REGS_H */
197