xref: /openbmc/qemu/target/ppc/helper_regs.h (revision db211f24)
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 #include "sysemu/kvm.h"
26 
27 /* Swap temporary saved registers with GPRs */
28 static inline void hreg_swap_gpr_tgpr(CPUPPCState *env)
29 {
30     target_ulong tmp;
31 
32     tmp = env->gpr[0];
33     env->gpr[0] = env->tgpr[0];
34     env->tgpr[0] = tmp;
35     tmp = env->gpr[1];
36     env->gpr[1] = env->tgpr[1];
37     env->tgpr[1] = tmp;
38     tmp = env->gpr[2];
39     env->gpr[2] = env->tgpr[2];
40     env->tgpr[2] = tmp;
41     tmp = env->gpr[3];
42     env->gpr[3] = env->tgpr[3];
43     env->tgpr[3] = tmp;
44 }
45 
46 static inline void hreg_compute_mem_idx(CPUPPCState *env)
47 {
48     /*
49      * This is our encoding for server processors. The architecture
50      * specifies that there is no such thing as userspace with
51      * translation off, however it appears that MacOS does it and some
52      * 32-bit CPUs support it. Weird...
53      *
54      *   0 = Guest User space virtual mode
55      *   1 = Guest Kernel space virtual mode
56      *   2 = Guest User space real mode
57      *   3 = Guest Kernel space real mode
58      *   4 = HV User space virtual mode
59      *   5 = HV Kernel space virtual mode
60      *   6 = HV User space real mode
61      *   7 = HV Kernel space real mode
62      *
63      * For BookE, we need 8 MMU modes as follow:
64      *
65      *  0 = AS 0 HV User space
66      *  1 = AS 0 HV Kernel space
67      *  2 = AS 1 HV User space
68      *  3 = AS 1 HV Kernel space
69      *  4 = AS 0 Guest User space
70      *  5 = AS 0 Guest Kernel space
71      *  6 = AS 1 Guest User space
72      *  7 = AS 1 Guest Kernel space
73      */
74     if (env->mmu_model & POWERPC_MMU_BOOKE) {
75         env->immu_idx = env->dmmu_idx = msr_pr ? 0 : 1;
76         env->immu_idx += msr_is ? 2 : 0;
77         env->dmmu_idx += msr_ds ? 2 : 0;
78         env->immu_idx += msr_gs ? 4 : 0;
79         env->dmmu_idx += msr_gs ? 4 : 0;
80     } else {
81         env->immu_idx = env->dmmu_idx = msr_pr ? 0 : 1;
82         env->immu_idx += msr_ir ? 0 : 2;
83         env->dmmu_idx += msr_dr ? 0 : 2;
84         env->immu_idx += msr_hv ? 4 : 0;
85         env->dmmu_idx += msr_hv ? 4 : 0;
86     }
87 }
88 
89 static inline void hreg_compute_hflags(CPUPPCState *env)
90 {
91     target_ulong hflags_mask;
92 
93     /* We 'forget' FE0 & FE1: we'll never generate imprecise exceptions */
94     hflags_mask = (1 << MSR_VR) | (1 << MSR_AP) | (1 << MSR_SA) |
95         (1 << MSR_PR) | (1 << MSR_FP) | (1 << MSR_SE) | (1 << MSR_BE) |
96         (1 << MSR_LE) | (1 << MSR_VSX) | (1 << MSR_IR) | (1 << MSR_DR);
97     hflags_mask |= (1ULL << MSR_CM) | (1ULL << MSR_SF) | MSR_HVB;
98     hreg_compute_mem_idx(env);
99     env->hflags = env->msr & hflags_mask;
100     /* Merge with hflags coming from other registers */
101     env->hflags |= env->hflags_nmsr;
102 }
103 
104 static inline void cpu_interrupt_exittb(CPUState *cs)
105 {
106     if (!kvm_enabled()) {
107         return;
108     }
109 
110     if (!qemu_mutex_iothread_locked()) {
111         qemu_mutex_lock_iothread();
112         cpu_interrupt(cs, CPU_INTERRUPT_EXITTB);
113         qemu_mutex_unlock_iothread();
114     } else {
115         cpu_interrupt(cs, CPU_INTERRUPT_EXITTB);
116     }
117 }
118 
119 static inline int hreg_store_msr(CPUPPCState *env, target_ulong value,
120                                  int alter_hv)
121 {
122     int excp;
123 #if !defined(CONFIG_USER_ONLY)
124     CPUState *cs = env_cpu(env);
125 #endif
126 
127     excp = 0;
128     value &= env->msr_mask;
129 #if !defined(CONFIG_USER_ONLY)
130     /* Neither mtmsr nor guest state can alter HV */
131     if (!alter_hv || !(env->msr & MSR_HVB)) {
132         value &= ~MSR_HVB;
133         value |= env->msr & MSR_HVB;
134     }
135     if (((value >> MSR_IR) & 1) != msr_ir ||
136         ((value >> MSR_DR) & 1) != msr_dr) {
137         cpu_interrupt_exittb(cs);
138     }
139     if ((env->mmu_model & POWERPC_MMU_BOOKE) &&
140         ((value >> MSR_GS) & 1) != msr_gs) {
141         cpu_interrupt_exittb(cs);
142     }
143     if (unlikely((env->flags & POWERPC_FLAG_TGPR) &&
144                  ((value ^ env->msr) & (1 << MSR_TGPR)))) {
145         /* Swap temporary saved registers with GPRs */
146         hreg_swap_gpr_tgpr(env);
147     }
148     if (unlikely((value >> MSR_EP) & 1) != msr_ep) {
149         /* Change the exception prefix on PowerPC 601 */
150         env->excp_prefix = ((value >> MSR_EP) & 1) * 0xFFF00000;
151     }
152     /*
153      * If PR=1 then EE, IR and DR must be 1
154      *
155      * Note: We only enforce this on 64-bit server processors.
156      * It appears that:
157      * - 32-bit implementations supports PR=1 and EE/DR/IR=0 and MacOS
158      *   exploits it.
159      * - 64-bit embedded implementations do not need any operation to be
160      *   performed when PR is set.
161      */
162     if (is_book3s_arch2x(env) && ((value >> MSR_PR) & 1)) {
163         value |= (1 << MSR_EE) | (1 << MSR_DR) | (1 << MSR_IR);
164     }
165 #endif
166     env->msr = value;
167     hreg_compute_hflags(env);
168 #if !defined(CONFIG_USER_ONLY)
169     if (unlikely(msr_pow == 1)) {
170         if (!env->pending_interrupts && (*env->check_pow)(env)) {
171             cs->halted = 1;
172             excp = EXCP_HALTED;
173         }
174     }
175 #endif
176 
177     return excp;
178 }
179 
180 #if !defined(CONFIG_USER_ONLY)
181 static inline void check_tlb_flush(CPUPPCState *env, bool global)
182 {
183     CPUState *cs = env_cpu(env);
184 
185     /* Handle global flushes first */
186     if (global && (env->tlb_need_flush & TLB_NEED_GLOBAL_FLUSH)) {
187         env->tlb_need_flush &= ~TLB_NEED_GLOBAL_FLUSH;
188         env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
189         tlb_flush_all_cpus_synced(cs);
190         return;
191     }
192 
193     /* Then handle local ones */
194     if (env->tlb_need_flush & TLB_NEED_LOCAL_FLUSH) {
195         env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
196         tlb_flush(cs);
197     }
198 }
199 #else
200 static inline void check_tlb_flush(CPUPPCState *env, bool global) { }
201 #endif
202 
203 #endif /* HELPER_REGS_H */
204