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 #define SHADOW_SLB_ENTRY_LEN    0x10
  21 #define OFFSET_ESID(x)          (SHADOW_SLB_ENTRY_LEN * x)
  22 #define OFFSET_VSID(x)          ((SHADOW_SLB_ENTRY_LEN * x) + 8)
  23
  24 /******************************************************************************
  25  *                                                                            *
  26  *                               Entry code                                   *
  27  *                                                                            *
  28  *****************************************************************************/
  29
  30 .macro LOAD_GUEST_SEGMENTS
  31
  32         /* Required state:
  33          *
  34          * MSR = ~IR|DR
  35          * R13 = PACA
  36          * R1 = host R1
  37          * R2 = host R2
  38          * R3 = shadow vcpu
  39          * all other volatile GPRS = free except R4, R6
  40          * SVCPU[CR]  = guest CR
  41          * SVCPU[XER] = guest XER
  42          * SVCPU[CTR] = guest CTR
  43          * SVCPU[LR]  = guest LR
  44          */
  45
  46 BEGIN_FW_FTR_SECTION
  47
  48         /* Declare SLB shadow as 0 entries big */
  49
  50         ld      r11, PACA_SLBSHADOWPTR(r13)
  51         li      r8, 0
  52         stb     r8, 3(r11)
  53
  54 END_FW_FTR_SECTION_IFSET(FW_FEATURE_LPAR)
  55
  56         /* Flush SLB */
  57
  58         li      r10, 0
  59         slbmte  r10, r10
  60         slbia
  61
  62         /* Fill SLB with our shadow */
  63
  64         lbz     r12, SVCPU_SLB_MAX(r3)
  65         mulli   r12, r12, 16
  66         addi    r12, r12, SVCPU_SLB
  67         add     r12, r12, r3
  68
  69         /* for (r11 = kvm_slb; r11 < kvm_slb + kvm_slb_size; r11+=slb_entry) */
  70         li      r11, SVCPU_SLB
  71         add     r11, r11, r3
  72
  73 slb_loop_enter:
  74
  75         ld      r10, 0(r11)
  76
  77         andis.  r9, r10, SLB_ESID_V@h
  78         beq     slb_loop_enter_skip
  79
  80         ld      r9, 8(r11)
  81         slbmte  r9, r10
  82
  83 slb_loop_enter_skip:
  84         addi    r11, r11, 16
  85         cmpd    cr0, r11, r12
  86         blt     slb_loop_enter
  87
  88 slb_do_enter:
  89
  90 .endm
  91
  92 /******************************************************************************
  93  *                                                                            *
  94  *                               Exit code                                    *
  95  *                                                                            *
  96  *****************************************************************************/
  97
  98 .macro LOAD_HOST_SEGMENTS
  99
 100         /* Register usage at this point:
 101          *
 102          * R1         = host R1
 103          * R2         = host R2
 104          * R12        = exit handler id
 105          * R13        = shadow vcpu - SHADOW_VCPU_OFF [=PACA on PPC64]
 106          * SVCPU.*    = guest *
 107          * SVCPU[CR]  = guest CR
 108          * SVCPU[XER] = guest XER
 109          * SVCPU[CTR] = guest CTR
 110          * SVCPU[LR]  = guest LR
 111          *
 112          */
 113
 114         /* Remove all SLB entries that are in use. */
 115
 116         li      r0, r0
 117         slbmte  r0, r0
 118         slbia
 119
 120         /* Restore bolted entries from the shadow */
 121
 122         ld      r11, PACA_SLBSHADOWPTR(r13)
 123
 124 BEGIN_FW_FTR_SECTION
 125
 126         /* Declare SLB shadow as SLB_NUM_BOLTED entries big */
 127
 128         li      r8, SLB_NUM_BOLTED
 129         stb     r8, 3(r11)
 130
 131 END_FW_FTR_SECTION_IFSET(FW_FEATURE_LPAR)
 132
 133         /* Manually load all entries from shadow SLB */
 134
 135         li      r8, SLBSHADOW_SAVEAREA
 136         li      r7, SLBSHADOW_SAVEAREA + 8
 137
 138         .rept   SLB_NUM_BOLTED
 139         LDX_BE  r10, r11, r8
 140         cmpdi   r10, 0
 141         beq     1f
 142         LDX_BE  r9, r11, r7
 143         slbmte  r9, r10
 144 1:      addi    r7, r7, SHADOW_SLB_ENTRY_LEN
 145         addi    r8, r8, SHADOW_SLB_ENTRY_LEN
 146         .endr
 147
 148         isync
 149         sync
 150
 151 slb_do_exit:
 152
 153 .endm