/* SPDX-License-Identifier: GPL-2.0-only */
/*
 *
 * Copyright SUSE Linux Products GmbH 2009
 *
 * Authors: Alexander Graf <agraf@suse.de>
 */

#include <asm/asm-compat.h>
#include <asm/feature-fixups.h>

#define SHADOW_SLB_ENTRY_LEN    0x10
#define OFFSET_ESID(x)          (SHADOW_SLB_ENTRY_LEN * x)
#define OFFSET_VSID(x)          ((SHADOW_SLB_ENTRY_LEN * x) + 8)

/******************************************************************************
 *                                                                            *
 *                               Entry code                                   *
 *                                                                            *
 *****************************************************************************/

.macro LOAD_GUEST_SEGMENTS

        /* Required state:
         *
         * MSR = ~IR|DR
         * R13 = PACA
         * R1 = host R1
         * R2 = host R2
         * R3 = shadow vcpu
         * all other volatile GPRS = free except R4, R6
         * SVCPU[CR]  = guest CR
         * SVCPU[XER] = guest XER
         * SVCPU[CTR] = guest CTR
         * SVCPU[LR]  = guest LR
         */

BEGIN_FW_FTR_SECTION

        /* Declare SLB shadow as 0 entries big */

        ld      r11, PACA_SLBSHADOWPTR(r13)
        li      r8, 0
        stb     r8, 3(r11)

END_FW_FTR_SECTION_IFSET(FW_FEATURE_LPAR)

        /* Flush SLB */

        li      r10, 0
        slbmte  r10, r10
        slbia

        /* Fill SLB with our shadow */

        lbz     r12, SVCPU_SLB_MAX(r3)
        mulli   r12, r12, 16
        addi    r12, r12, SVCPU_SLB
        add     r12, r12, r3

        /* for (r11 = kvm_slb; r11 < kvm_slb + kvm_slb_size; r11+=slb_entry) */
        li      r11, SVCPU_SLB
        add     r11, r11, r3

slb_loop_enter:

        ld      r10, 0(r11)

        andis.  r9, r10, SLB_ESID_V@h
        beq     slb_loop_enter_skip

        ld      r9, 8(r11)
        slbmte  r9, r10

slb_loop_enter_skip:
        addi    r11, r11, 16
        cmpd    cr0, r11, r12
        blt     slb_loop_enter

slb_do_enter:

.endm

/******************************************************************************
 *                                                                            *
 *                               Exit code                                    *
 *                                                                            *
 *****************************************************************************/

.macro LOAD_HOST_SEGMENTS

        /* Register usage at this point:
         *
         * R1         = host R1
         * R2         = host R2
         * R12        = exit handler id
         * R13        = shadow vcpu - SHADOW_VCPU_OFF [=PACA on PPC64]
         * SVCPU.*    = guest *
         * SVCPU[CR]  = guest CR
         * SVCPU[XER] = guest XER
         * SVCPU[CTR] = guest CTR
         * SVCPU[LR]  = guest LR
         *
         */

        /* Remove all SLB entries that are in use. */

        li      r0, 0
        slbmte  r0, r0
        slbia

        /* Restore bolted entries from the shadow */

        ld      r11, PACA_SLBSHADOWPTR(r13)

BEGIN_FW_FTR_SECTION

        /* Declare SLB shadow as SLB_NUM_BOLTED entries big */

        li      r8, SLB_NUM_BOLTED
        stb     r8, 3(r11)

END_FW_FTR_SECTION_IFSET(FW_FEATURE_LPAR)

        /* Manually load all entries from shadow SLB */

        li      r8, SLBSHADOW_SAVEAREA
        li      r7, SLBSHADOW_SAVEAREA + 8

        .rept   SLB_NUM_BOLTED
        LDX_BE  r10, r11, r8
        cmpdi   r10, 0
        beq     1f
        LDX_BE  r9, r11, r7
        slbmte  r9, r10
1:      addi    r7, r7, SHADOW_SLB_ENTRY_LEN
        addi    r8, r8, SHADOW_SLB_ENTRY_LEN
        .endr

        isync
        sync

slb_do_exit:

.endm