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+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Copyright SUSE Linux Products GmbH 2009
+ *
+ * Authors: Alexander Graf <agraf@suse.de>
+ */
+
+/******************************************************************************
+ * *
+ * Entry code *
+ * *
+ *****************************************************************************/
+
+.macro LOAD_GUEST_SEGMENTS
+
+ /* Required state:
+ *
+ * MSR = ~IR|DR
+ * R1 = host R1
+ * R2 = host R2
+ * R3 = shadow vcpu
+ * all other volatile GPRS = free
+ * SVCPU[CR] = guest CR
+ * SVCPU[XER] = guest XER
+ * SVCPU[CTR] = guest CTR
+ * SVCPU[LR] = guest LR
+ */
+
+#define XCHG_SR(n) lwz r9, (SVCPU_SR+(n*4))(r3); \
+ mtsr n, r9
+
+ XCHG_SR(0)
+ XCHG_SR(1)
+ XCHG_SR(2)
+ XCHG_SR(3)
+ XCHG_SR(4)
+ XCHG_SR(5)
+ XCHG_SR(6)
+ XCHG_SR(7)
+ XCHG_SR(8)
+ XCHG_SR(9)
+ XCHG_SR(10)
+ XCHG_SR(11)
+ XCHG_SR(12)
+ XCHG_SR(13)
+ XCHG_SR(14)
+ XCHG_SR(15)
+
+ /* Clear BATs. */
+
+#define KVM_KILL_BAT(n, reg) \
+ mtspr SPRN_IBAT##n##U,reg; \
+ mtspr SPRN_IBAT##n##L,reg; \
+ mtspr SPRN_DBAT##n##U,reg; \
+ mtspr SPRN_DBAT##n##L,reg; \
+
+ li r9, 0
+ KVM_KILL_BAT(0, r9)
+ KVM_KILL_BAT(1, r9)
+ KVM_KILL_BAT(2, r9)
+ KVM_KILL_BAT(3, r9)
+
+.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
+ * SVCPU.* = guest *
+ * SVCPU[CR] = guest CR
+ * SVCPU[XER] = guest XER
+ * SVCPU[CTR] = guest CTR
+ * SVCPU[LR] = guest LR
+ *
+ */
+
+ /* Restore BATs */
+
+ /* We only overwrite the upper part, so we only restoree
+ the upper part. */
+#define KVM_LOAD_BAT(n, reg, RA, RB) \
+ lwz RA,(n*16)+0(reg); \
+ lwz RB,(n*16)+4(reg); \
+ mtspr SPRN_IBAT##n##U,RA; \
+ mtspr SPRN_IBAT##n##L,RB; \
+ lwz RA,(n*16)+8(reg); \
+ lwz RB,(n*16)+12(reg); \
+ mtspr SPRN_DBAT##n##U,RA; \
+ mtspr SPRN_DBAT##n##L,RB; \
+
+ lis r9, BATS@ha
+ addi r9, r9, BATS@l
+ tophys(r9, r9)
+ KVM_LOAD_BAT(0, r9, r10, r11)
+ KVM_LOAD_BAT(1, r9, r10, r11)
+ KVM_LOAD_BAT(2, r9, r10, r11)
+ KVM_LOAD_BAT(3, r9, r10, r11)
+
+ /* Restore Segment Registers */
+
+ /* 0xc - 0xf */
+
+ li r0, 4
+ mtctr r0
+ LOAD_REG_IMMEDIATE(r3, 0x20000000 | (0x111 * 0xc))
+ lis r4, 0xc000
+3: mtsrin r3, r4
+ addi r3, r3, 0x111 /* increment VSID */
+ addis r4, r4, 0x1000 /* address of next segment */
+ bdnz 3b
+
+ /* 0x0 - 0xb */
+
+ /* 'current->mm' needs to be in r4 */
+ tophys(r4, r2)
+ lwz r4, MM(r4)
+ tophys(r4, r4)
+ /* This only clobbers r0, r3, r4 and r5 */
+ bl switch_mmu_context
+
+.endm