arch/powerpc/kvm/book3s_64_slb.S

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License, version 2, as
   4  * published by the Free Software Foundation.
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  * GNU General Public License for more details.
  10  *
  11  * You should have received a copy of the GNU General Public License
  12  * along with this program; if not, write to the Free Software
  13  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  14  *
  15  * Copyright SUSE Linux Products GmbH 2009
  16  *
  17  * Authors: Alexander Graf <agraf@suse.de>
  18  */
  19
  20 #ifdef __LITTLE_ENDIAN__
  21 #error Need to fix SLB shadow accesses in little endian mode
  22 #endif
  23
  24 #define SHADOW_SLB_ESID(num)    (SLBSHADOW_SAVEAREA + (num * 0x10))
  25 #define SHADOW_SLB_VSID(num)    (SLBSHADOW_SAVEAREA + (num * 0x10) + 0x8)
  26 #define UNBOLT_SLB_ENTRY(num) \
  27         ld      r9, SHADOW_SLB_ESID(num)(r12); \
  28         /* Invalid? Skip. */; \
  29         rldicl. r0, r9, 37, 63; \
  30         beq     slb_entry_skip_ ## num; \
  31         xoris   r9, r9, SLB_ESID_V@h; \
  32         std     r9, SHADOW_SLB_ESID(num)(r12); \
  33   slb_entry_skip_ ## num:
  34
  35 #define REBOLT_SLB_ENTRY(num) \
  36         ld      r10, SHADOW_SLB_ESID(num)(r11); \
  37         cmpdi   r10, 0; \
  38         beq     slb_exit_skip_ ## num; \
  39         oris    r10, r10, SLB_ESID_V@h; \
  40         ld      r9, SHADOW_SLB_VSID(num)(r11); \
  41         slbmte  r9, r10; \
  42         std     r10, SHADOW_SLB_ESID(num)(r11); \
  43 slb_exit_skip_ ## num:
  44
  45 /******************************************************************************
  46  *                                                                            *
  47  *                               Entry code                                   *
  48  *                                                                            *
  49  *****************************************************************************/
  50
  51 .macro LOAD_GUEST_SEGMENTS
  52
  53         /* Required state:
  54          *
  55          * MSR = ~IR|DR
  56          * R13 = PACA
  57          * R1 = host R1
  58          * R2 = host R2
  59          * R3 = shadow vcpu
  60          * all other volatile GPRS = free except R4, R6
  61          * SVCPU[CR]  = guest CR
  62          * SVCPU[XER] = guest XER
  63          * SVCPU[CTR] = guest CTR
  64          * SVCPU[LR]  = guest LR
  65          */
  66
  67         /* Remove LPAR shadow entries */
  68
  69 #if SLB_NUM_BOLTED == 3
  70
  71         ld      r12, PACA_SLBSHADOWPTR(r13)
  72
  73         /* Remove bolted entries */
  74         UNBOLT_SLB_ENTRY(0)
  75         UNBOLT_SLB_ENTRY(1)
  76         UNBOLT_SLB_ENTRY(2)
  77
  78 #else
  79 #error unknown number of bolted entries
  80 #endif
  81
  82         /* Flush SLB */
  83
  84         li      r10, 0
  85         slbmte  r10, r10
  86         slbia
  87
  88         /* Fill SLB with our shadow */
  89
  90         lbz     r12, SVCPU_SLB_MAX(r3)
  91         mulli   r12, r12, 16
  92         addi    r12, r12, SVCPU_SLB
  93         add     r12, r12, r3
  94
  95         /* for (r11 = kvm_slb; r11 < kvm_slb + kvm_slb_size; r11+=slb_entry) */
  96         li      r11, SVCPU_SLB
  97         add     r11, r11, r3
  98
  99 slb_loop_enter:
 100
 101         ld      r10, 0(r11)
 102
 103         rldicl. r0, r10, 37, 63
 104         beq     slb_loop_enter_skip
 105
 106         ld      r9, 8(r11)
 107         slbmte  r9, r10
 108
 109 slb_loop_enter_skip:
 110         addi    r11, r11, 16
 111         cmpd    cr0, r11, r12
 112         blt     slb_loop_enter
 113
 114 slb_do_enter:
 115
 116 .endm
 117
 118 /******************************************************************************
 119  *                                                                            *
 120  *                               Exit code                                    *
 121  *                                                                            *
 122  *****************************************************************************/
 123
 124 .macro LOAD_HOST_SEGMENTS
 125
 126         /* Register usage at this point:
 127          *
 128          * R1         = host R1
 129          * R2         = host R2
 130          * R12        = exit handler id
 131          * R13        = shadow vcpu - SHADOW_VCPU_OFF [=PACA on PPC64]
 132          * SVCPU.*    = guest *
 133          * SVCPU[CR]  = guest CR
 134          * SVCPU[XER] = guest XER
 135          * SVCPU[CTR] = guest CTR
 136          * SVCPU[LR]  = guest LR
 137          *
 138          */
 139
 140         /* Restore bolted entries from the shadow and fix it along the way */
 141
 142         /* We don't store anything in entry 0, so we don't need to take care of it */
 143         slbia
 144         isync
 145
 146 #if SLB_NUM_BOLTED == 3
 147
 148         ld      r11, PACA_SLBSHADOWPTR(r13)
 149
 150         REBOLT_SLB_ENTRY(0)
 151         REBOLT_SLB_ENTRY(1)
 152         REBOLT_SLB_ENTRY(2)
 153
 154 #else
 155 #error unknown number of bolted entries
 156 #endif
 157
 158 slb_do_exit:
 159
 160 .endm