target-ppc/helper_regs.h

   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 #if !defined(__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     /* Precompute MMU index */
  45     if (msr_pr == 0 && msr_hv != 0) {
  46         env->mmu_idx = 2;
  47     } else {
  48         env->mmu_idx = 1 - msr_pr;
  49     }
  50 }
  51
  52 static inline void hreg_compute_hflags(CPUPPCState *env)
  53 {
  54     target_ulong hflags_mask;
  55
  56     /* We 'forget' FE0 & FE1: we'll never generate imprecise exceptions */
  57     hflags_mask = (1 << MSR_VR) | (1 << MSR_AP) | (1 << MSR_SA) |
  58         (1 << MSR_PR) | (1 << MSR_FP) | (1 << MSR_SE) | (1 << MSR_BE) |
  59         (1 << MSR_LE);
  60     hflags_mask |= (1ULL << MSR_CM) | (1ULL << MSR_SF) | MSR_HVB;
  61     hreg_compute_mem_idx(env);
  62     env->hflags = env->msr & hflags_mask;
  63     /* Merge with hflags coming from other registers */
  64     env->hflags |= env->hflags_nmsr;
  65 }
  66
  67 static inline int hreg_store_msr(CPUPPCState *env, target_ulong value,
  68                                  int alter_hv)
  69 {
  70     int excp;
  71
  72     excp = 0;
  73     value &= env->msr_mask;
  74 #if !defined (CONFIG_USER_ONLY)
  75     if (!alter_hv) {
  76         /* mtmsr cannot alter the hypervisor state */
  77         value &= ~MSR_HVB;
  78         value |= env->msr & MSR_HVB;
  79     }
  80     if (((value >> MSR_IR) & 1) != msr_ir ||
  81         ((value >> MSR_DR) & 1) != msr_dr) {
  82         /* Flush all tlb when changing translation mode */
  83         tlb_flush(env, 1);
  84         excp = POWERPC_EXCP_NONE;
  85         env->interrupt_request |= CPU_INTERRUPT_EXITTB;
  86     }
  87     if (unlikely((env->flags & POWERPC_FLAG_TGPR) &&
  88                  ((value ^ env->msr) & (1 << MSR_TGPR)))) {
  89         /* Swap temporary saved registers with GPRs */
  90         hreg_swap_gpr_tgpr(env);
  91     }
  92     if (unlikely((value >> MSR_EP) & 1) != msr_ep) {
  93         /* Change the exception prefix on PowerPC 601 */
  94         env->excp_prefix = ((value >> MSR_EP) & 1) * 0xFFF00000;
  95     }
  96 #endif
  97     env->msr = value;
  98     hreg_compute_hflags(env);
  99 #if !defined (CONFIG_USER_ONLY)
 100     if (unlikely(msr_pow == 1)) {
 101         if ((*env->check_pow)(env)) {
 102             env->halted = 1;
 103             excp = EXCP_HALTED;
 104         }
 105     }
 106 #endif
 107
 108     return excp;
 109 }
 110
 111 #endif /* !defined(__HELPER_REGS_H__) */