diff mbox

[08/28] Add SLB switching code for entry/exit

Message ID 1257199351-2238-1-git-send-email-agraf@suse.de (mailing list archive)
State New, archived
Headers show

Commit Message

Alexander Graf Nov. 2, 2009, 10:02 p.m. UTC
None
diff mbox

Patch

diff --git a/arch/powerpc/kvm/book3s_64_slb.S b/arch/powerpc/kvm/book3s_64_slb.S
new file mode 100644
index 0000000..ecd237a
--- /dev/null
+++ b/arch/powerpc/kvm/book3s_64_slb.S
@@ -0,0 +1,262 @@ 
+/*
+ * 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>
+ */
+
+#define SHADOW_SLB_ESID(num)	(SLBSHADOW_SAVEAREA + (num * 0x10))
+#define SHADOW_SLB_VSID(num)	(SLBSHADOW_SAVEAREA + (num * 0x10) + 0x8)
+#define UNBOLT_SLB_ENTRY(num) \
+	ld	r9, SHADOW_SLB_ESID(num)(r12); \
+	/* Invalid? Skip. */; \
+	rldicl. r0, r9, 37, 63; \
+	beq	slb_entry_skip_ ## num; \
+	xoris	r9, r9, SLB_ESID_V@h; \
+	std	r9, SHADOW_SLB_ESID(num)(r12); \
+  slb_entry_skip_ ## num:
+
+#define REBOLT_SLB_ENTRY(num) \
+	ld	r10, SHADOW_SLB_ESID(num)(r11); \
+	cmpdi	r10, 0; \
+	beq	slb_exit_skip_1; \
+	oris	r10, r10, SLB_ESID_V@h; \
+	ld	r9, SHADOW_SLB_VSID(num)(r11); \
+	slbmte	r9, r10; \
+	std	r10, SHADOW_SLB_ESID(num)(r11); \
+slb_exit_skip_ ## num:
+
+/******************************************************************************
+ *                                                                            *
+ *                               Entry code                                   *
+ *                                                                            *
+ *****************************************************************************/
+
+.global kvmppc_handler_trampoline_enter
+kvmppc_handler_trampoline_enter:
+
+	/* Required state:
+	 *
+	 * MSR = ~IR|DR
+	 * R13 = PACA
+	 * R9 = guest IP
+	 * R10 = guest MSR
+	 * R11 = free
+	 * R12 = free
+	 * PACA[PACA_EXMC + EX_R9] = guest R9
+	 * PACA[PACA_EXMC + EX_R10] = guest R10
+	 * PACA[PACA_EXMC + EX_R11] = guest R11
+	 * PACA[PACA_EXMC + EX_R12] = guest R12
+	 * PACA[PACA_EXMC + EX_R13] = guest R13
+	 * PACA[PACA_EXMC + EX_CCR] = guest CR
+	 * PACA[PACA_EXMC + EX_R3] = guest XER
+	 */
+
+	mtsrr0	r9
+	mtsrr1	r10
+
+	mtspr	SPRN_SPRG_SCRATCH0, r0
+
+	/* Remove LPAR shadow entries */
+
+#if SLB_NUM_BOLTED == 3
+
+	ld	r12, PACA_SLBSHADOWPTR(r13)
+
+	/* Save off the first entry so we can slbie it later */
+	ld	r10, SHADOW_SLB_ESID(0)(r12)
+	ld	r11, SHADOW_SLB_VSID(0)(r12)
+
+	/* Remove bolted entries */
+	UNBOLT_SLB_ENTRY(0)
+	UNBOLT_SLB_ENTRY(1)
+	UNBOLT_SLB_ENTRY(2)
+	
+#else
+#error unknown number of bolted entries
+#endif
+
+	/* Flush SLB */
+
+	slbia
+
+	/* r0 = esid & ESID_MASK */
+	rldicr  r10, r10, 0, 35
+	/* r0 |= CLASS_BIT(VSID) */
+	rldic   r12, r11, 56 - 36, 36
+	or      r10, r10, r12
+	slbie	r10
+
+	isync
+
+	/* Fill SLB with our shadow */
+
+	lbz	r12, PACA_KVM_SLB_MAX(r13)
+	mulli	r12, r12, 16
+	addi	r12, r12, PACA_KVM_SLB
+	add	r12, r12, r13
+
+	/* for (r11 = kvm_slb; r11 < kvm_slb + kvm_slb_size; r11+=slb_entry) */
+	li	r11, PACA_KVM_SLB
+	add	r11, r11, r13
+
+slb_loop_enter:
+
+	ld	r10, 0(r11)
+
+	rldicl. r0, r10, 37, 63
+	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:
+
+	/* Enter guest */
+
+	mfspr	r0, SPRN_SPRG_SCRATCH0
+
+	ld	r9, (PACA_EXMC+EX_R9)(r13)
+	ld	r10, (PACA_EXMC+EX_R10)(r13)
+	ld	r12, (PACA_EXMC+EX_R12)(r13)
+
+	lwz	r11, (PACA_EXMC+EX_CCR)(r13)
+	mtcr	r11
+
+	ld	r11, (PACA_EXMC+EX_R3)(r13)
+	mtxer	r11
+
+	ld	r11, (PACA_EXMC+EX_R11)(r13)
+	ld	r13, (PACA_EXMC+EX_R13)(r13)
+
+	RFI
+kvmppc_handler_trampoline_enter_end:
+
+
+
+/******************************************************************************
+ *                                                                            *
+ *                               Exit code                                    *
+ *                                                                            *
+ *****************************************************************************/
+
+.global kvmppc_handler_trampoline_exit
+kvmppc_handler_trampoline_exit:
+
+	/* Register usage at this point:
+	 *
+	 * SPRG_SCRATCH0 = guest R13
+	 * R01           = host R1
+	 * R02           = host R2
+	 * R10           = guest PC
+	 * R11           = guest MSR
+	 * R12           = exit handler id
+	 * R13           = PACA
+	 * PACA.exmc.CCR  = guest CR
+	 * PACA.exmc.R9  = guest R1
+	 * PACA.exmc.R10 = guest R10
+	 * PACA.exmc.R11 = guest R11
+	 * PACA.exmc.R12 = guest R12
+	 * PACA.exmc.R13 = guest R2
+	 *
+	 */
+
+	/* Save registers */
+
+	std	r0, (PACA_EXMC+EX_SRR0)(r13)
+	std	r9, (PACA_EXMC+EX_R3)(r13)
+	std	r10, (PACA_EXMC+EX_LR)(r13)
+	std	r11, (PACA_EXMC+EX_DAR)(r13)
+
+	/*
+	 * In order for us to easily get the last instruction,
+	 * we got the #vmexit at, we exploit the fact that the
+	 * virtual layout is still the same here, so we can just
+	 * ld from the guest's PC address
+	 */
+
+	/* We only load the last instruction when it's safe */
+	cmpwi	r12, BOOK3S_INTERRUPT_DATA_STORAGE
+	beq	ld_last_inst
+	cmpwi	r12, BOOK3S_INTERRUPT_PROGRAM
+	beq	ld_last_inst
+
+	b	no_ld_last_inst
+
+ld_last_inst:
+	/* Save off the guest instruction we're at */
+	/*    1) enable paging for data */
+	mfmsr	r9
+	ori	r11, r9, MSR_DR			/* Enable paging for data */
+	mtmsr	r11
+	/*    2) fetch the instruction */
+	lwz	r0, 0(r10)
+	/*    3) disable paging again */
+	mtmsr	r9
+
+no_ld_last_inst:
+
+	/* Restore bolted entries from the shadow and fix it along the way */
+
+	/* We don't store anything in entry 0, so we don't need to take care of it */
+	slbia
+	isync
+
+#if SLB_NUM_BOLTED == 3
+
+	ld	r11, PACA_SLBSHADOWPTR(r13)
+
+	REBOLT_SLB_ENTRY(0)
+	REBOLT_SLB_ENTRY(1)
+	REBOLT_SLB_ENTRY(2)
+	
+#else
+#error unknown number of bolted entries
+#endif
+
+slb_do_exit:
+
+	/* Restore registers */
+
+	ld	r11, (PACA_EXMC+EX_DAR)(r13)
+	ld	r10, (PACA_EXMC+EX_LR)(r13)
+	ld	r9, (PACA_EXMC+EX_R3)(r13)
+
+	/* Save last inst */
+	stw	r0, (PACA_EXMC+EX_LR)(r13)
+
+	/* Save DAR and DSISR before going to paged mode */
+	mfdar	r0
+	std	r0, (PACA_EXMC+EX_DAR)(r13)
+	mfdsisr	r0
+	stw	r0, (PACA_EXMC+EX_DSISR)(r13)
+
+	/* RFI into the highmem handler */
+	mfmsr	r0
+	ori	r0, r0, MSR_IR|MSR_DR|MSR_RI	/* Enable paging */
+	mtsrr1	r0
+	ld	r0, PACASAVEDMSR(r13)		/* Highmem handler address */
+	mtsrr0	r0
+
+	mfspr	r0, SPRN_SPRG_SCRATCH0
+
+	RFI
+kvmppc_handler_trampoline_exit_end:
+