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, write to the Free Software

    18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    19  */

    20 

    21 #if !defined(__HELPER_REGS_H__)

    22 #define __HELPER_REGS_H__

    23 

    24 /* Swap temporary saved registers with GPRs */

    25 static always_inline void hreg_swap_gpr_tgpr (CPUPPCState *env)

    26 {

    27     target_ulong tmp;

    28 

    29     tmp = env->gpr[0];

    30     env->gpr[0] = env->tgpr[0];

    31     env->tgpr[0] = tmp;

    32     tmp = env->gpr[1];

    33     env->gpr[1] = env->tgpr[1];

    34     env->tgpr[1] = tmp;

    35     tmp = env->gpr[2];

    36     env->gpr[2] = env->tgpr[2];

    37     env->tgpr[2] = tmp;

    38     tmp = env->gpr[3];

    39     env->gpr[3] = env->tgpr[3];

    40     env->tgpr[3] = tmp;

    41 }

    42 

    43 static always_inline void hreg_compute_mem_idx (CPUPPCState *env)

    44 {

    45     /* Precompute MMU index */

    46     if (msr_pr == 0 && msr_hv != 0) {

    47         env->mmu_idx = 2;

    48     } else {

    49         env->mmu_idx = 1 - msr_pr;

    50     }

    51 }

    52 

    53 static always_inline void hreg_compute_hflags (CPUPPCState *env)

    54 {

    55     target_ulong hflags_mask;

    56 

    57     /* We 'forget' FE0 & FE1: we'll never generate imprecise exceptions */

    58     hflags_mask = (1 << MSR_VR) | (1 << MSR_AP) | (1 << MSR_SA) |

    59         (1 << MSR_PR) | (1 << MSR_FP) | (1 << MSR_SE) | (1 << MSR_BE) |

    60         (1 << MSR_LE);

    61     hflags_mask |= (1ULL << MSR_CM) | (1ULL << MSR_SF) | MSR_HVB;

    62     hreg_compute_mem_idx(env);

    63     env->hflags = env->msr & hflags_mask;

    64     /* Merge with hflags coming from other registers */

    65     env->hflags |= env->hflags_nmsr;

    66 }

    67 

    68 static always_inline int hreg_store_msr (CPUPPCState *env, target_ulong value,

    69                                          int alter_hv)

    70 {

    71     int excp;

    72 

    73     excp = 0;

    74     value &= env->msr_mask;

    75 #if !defined (CONFIG_USER_ONLY)

    76     if (!alter_hv) {

    77         /* mtmsr cannot alter the hypervisor state */

    78         value &= ~MSR_HVB;

    79         value |= env->msr & MSR_HVB;

    80     }

    81     if (((value >> MSR_IR) & 1) != msr_ir ||

    82         ((value >> MSR_DR) & 1) != msr_dr) {

    83         /* Flush all tlb when changing translation mode */

    84         tlb_flush(env, 1);

    85         excp = POWERPC_EXCP_NONE;

    86         env->interrupt_request |= CPU_INTERRUPT_EXITTB;

    87     }

    88     if (unlikely((env->flags & POWERPC_FLAG_TGPR) &&

    89                  ((value ^ env->msr) & (1 << MSR_TGPR)))) {

    90         /* Swap temporary saved registers with GPRs */

    91         hreg_swap_gpr_tgpr(env);

    92     }

    93     if (unlikely((value >> MSR_EP) & 1) != msr_ep) {

    94         /* Change the exception prefix on PowerPC 601 */

    95         env->excp_prefix = ((value >> MSR_EP) & 1) * 0xFFF00000;

    96     }

    97 #endif

    98     env->msr = value;

    99     hreg_compute_hflags(env);

   100 #if !defined (CONFIG_USER_ONLY)

   101     if (unlikely(msr_pow == 1)) {

   102         if ((*env->check_pow)(env)) {

   103             env->halted = 1;

   104             excp = EXCP_HALTED;

   105         }

   106     }

   107 #endif

   108 

   109     return excp;

   110 }

   111 

   112 #endif /* !defined(__HELPER_REGS_H__) */