xref: /openbmc/qemu/target/ppc/helper_regs.h (revision a9ded601)
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 /* Swap temporary saved registers with GPRs */
24 static inline void hreg_swap_gpr_tgpr(CPUPPCState *env)
25 {
26     target_ulong tmp;
27 
28     tmp = env->gpr[0];
29     env->gpr[0] = env->tgpr[0];
30     env->tgpr[0] = tmp;
31     tmp = env->gpr[1];
32     env->gpr[1] = env->tgpr[1];
33     env->tgpr[1] = tmp;
34     tmp = env->gpr[2];
35     env->gpr[2] = env->tgpr[2];
36     env->tgpr[2] = tmp;
37     tmp = env->gpr[3];
38     env->gpr[3] = env->tgpr[3];
39     env->tgpr[3] = tmp;
40 }
41 
42 static inline void hreg_compute_mem_idx(CPUPPCState *env)
43 {
44     /* This is our encoding for server processors. The architecture
45      * specifies that there is no such thing as userspace with
46      * translation off, however it appears that MacOS does it and
47      * some 32-bit CPUs support it. Weird...
48      *
49      *   0 = Guest User space virtual mode
50      *   1 = Guest Kernel space virtual mode
51      *   2 = Guest User space real mode
52      *   3 = Guest Kernel space real mode
53      *   4 = HV User space virtual mode
54      *   5 = HV Kernel space virtual mode
55      *   6 = HV User space real mode
56      *   7 = HV Kernel space real mode
57      *
58      * For BookE, we need 8 MMU modes as follow:
59      *
60      *  0 = AS 0 HV User space
61      *  1 = AS 0 HV Kernel space
62      *  2 = AS 1 HV User space
63      *  3 = AS 1 HV Kernel space
64      *  4 = AS 0 Guest User space
65      *  5 = AS 0 Guest Kernel space
66      *  6 = AS 1 Guest User space
67      *  7 = AS 1 Guest Kernel space
68      */
69     if (env->mmu_model & POWERPC_MMU_BOOKE) {
70         env->immu_idx = env->dmmu_idx = msr_pr ? 0 : 1;
71         env->immu_idx += msr_is ? 2 : 0;
72         env->dmmu_idx += msr_ds ? 2 : 0;
73         env->immu_idx += msr_gs ? 4 : 0;
74         env->dmmu_idx += msr_gs ? 4 : 0;
75     } else {
76         env->immu_idx = env->dmmu_idx = msr_pr ? 0 : 1;
77         env->immu_idx += msr_ir ? 0 : 2;
78         env->dmmu_idx += msr_dr ? 0 : 2;
79         env->immu_idx += msr_hv ? 4 : 0;
80         env->dmmu_idx += msr_hv ? 4 : 0;
81     }
82 }
83 
84 static inline void hreg_compute_hflags(CPUPPCState *env)
85 {
86     target_ulong hflags_mask;
87 
88     /* We 'forget' FE0 & FE1: we'll never generate imprecise exceptions */
89     hflags_mask = (1 << MSR_VR) | (1 << MSR_AP) | (1 << MSR_SA) |
90         (1 << MSR_PR) | (1 << MSR_FP) | (1 << MSR_SE) | (1 << MSR_BE) |
91         (1 << MSR_LE) | (1 << MSR_VSX) | (1 << MSR_IR) | (1 << MSR_DR);
92     hflags_mask |= (1ULL << MSR_CM) | (1ULL << MSR_SF) | MSR_HVB;
93     hreg_compute_mem_idx(env);
94     env->hflags = env->msr & hflags_mask;
95     /* Merge with hflags coming from other registers */
96     env->hflags |= env->hflags_nmsr;
97 }
98 
99 static inline int hreg_store_msr(CPUPPCState *env, target_ulong value,
100                                  int alter_hv)
101 {
102     int excp;
103 #if !defined(CONFIG_USER_ONLY)
104     CPUState *cs = CPU(ppc_env_get_cpu(env));
105 #endif
106 
107     excp = 0;
108     value &= env->msr_mask;
109 #if !defined(CONFIG_USER_ONLY)
110     /* Neither mtmsr nor guest state can alter HV */
111     if (!alter_hv || !(env->msr & MSR_HVB)) {
112         value &= ~MSR_HVB;
113         value |= env->msr & MSR_HVB;
114     }
115     if (((value >> MSR_IR) & 1) != msr_ir ||
116         ((value >> MSR_DR) & 1) != msr_dr) {
117         cs->interrupt_request |= CPU_INTERRUPT_EXITTB;
118     }
119     if ((env->mmu_model & POWERPC_MMU_BOOKE) &&
120         ((value >> MSR_GS) & 1) != msr_gs) {
121         cs->interrupt_request |= CPU_INTERRUPT_EXITTB;
122     }
123     if (unlikely((env->flags & POWERPC_FLAG_TGPR) &&
124                  ((value ^ env->msr) & (1 << MSR_TGPR)))) {
125         /* Swap temporary saved registers with GPRs */
126         hreg_swap_gpr_tgpr(env);
127     }
128     if (unlikely((value >> MSR_EP) & 1) != msr_ep) {
129         /* Change the exception prefix on PowerPC 601 */
130         env->excp_prefix = ((value >> MSR_EP) & 1) * 0xFFF00000;
131     }
132     /* If PR=1 then EE, IR and DR must be 1
133      *
134      * Note: We only enforce this on 64-bit server processors.
135      * It appears that:
136      * - 32-bit implementations supports PR=1 and EE/DR/IR=0 and MacOS
137      *   exploits it.
138      * - 64-bit embedded implementations do not need any operation to be
139      *   performed when PR is set.
140      */
141     if ((env->insns_flags & PPC_SEGMENT_64B) && ((value >> MSR_PR) & 1)) {
142         value |= (1 << MSR_EE) | (1 << MSR_DR) | (1 << MSR_IR);
143     }
144 #endif
145     env->msr = value;
146     hreg_compute_hflags(env);
147 #if !defined(CONFIG_USER_ONLY)
148     if (unlikely(msr_pow == 1)) {
149         if (!env->pending_interrupts && (*env->check_pow)(env)) {
150             cs->halted = 1;
151             excp = EXCP_HALTED;
152         }
153     }
154 #endif
155 
156     return excp;
157 }
158 
159 #if !defined(CONFIG_USER_ONLY)
160 static inline void check_tlb_flush(CPUPPCState *env, bool global)
161 {
162     CPUState *cs = CPU(ppc_env_get_cpu(env));
163     if (env->tlb_need_flush & TLB_NEED_LOCAL_FLUSH) {
164         tlb_flush(cs);
165         env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
166     }
167 
168     /* Propagate TLB invalidations to other CPUs when the guest uses broadcast
169      * TLB invalidation instructions.
170      */
171     if (global && (env->tlb_need_flush & TLB_NEED_GLOBAL_FLUSH)) {
172         CPUState *other_cs;
173         CPU_FOREACH(other_cs) {
174             if (other_cs != cs) {
175                 PowerPCCPU *cpu = POWERPC_CPU(other_cs);
176                 CPUPPCState *other_env = &cpu->env;
177 
178                 other_env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
179                 tlb_flush(other_cs);
180             }
181         }
182         env->tlb_need_flush &= ~TLB_NEED_GLOBAL_FLUSH;
183     }
184 }
185 #else
186 static inline void check_tlb_flush(CPUPPCState *env, bool global) { }
187 #endif
188 
189 #endif /* HELPER_REGS_H */
190