diff mbox

[07/27] Add book3s_64 highmem asm code

Message ID 1256137413-15256-8-git-send-email-agraf@suse.de (mailing list archive)
State New, archived
Headers show

Commit Message

Alexander Graf Oct. 21, 2009, 3:03 p.m. UTC
None
diff mbox

Patch

diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 2c6ee34..269ee46 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -39,6 +39,7 @@  enum emulation_result {
 extern int __kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu);
 extern char kvmppc_handlers_start[];
 extern unsigned long kvmppc_handler_len;
+extern void kvmppc_handler_highmem(void);
 
 extern void kvmppc_dump_vcpu(struct kvm_vcpu *vcpu);
 extern int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
diff --git a/arch/powerpc/kvm/book3s_64_interrupts.S b/arch/powerpc/kvm/book3s_64_interrupts.S
new file mode 100644
index 0000000..7b55d80
--- /dev/null
+++ b/arch/powerpc/kvm/book3s_64_interrupts.S
@@ -0,0 +1,392 @@ 
+/*
+ * 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>
+ */
+
+#include <asm/ppc_asm.h>
+#include <asm/kvm_asm.h>
+#include <asm/reg.h>
+#include <asm/page.h>
+#include <asm/asm-offsets.h>
+#include <asm/exception-64s.h>
+
+#define KVMPPC_HANDLE_EXIT .kvmppc_handle_exit
+#define ULONG_SIZE 8
+#define VCPU_GPR(n)     (VCPU_GPRS + (n * ULONG_SIZE))
+
+.macro mfpaca tmp_reg, src_reg, offset, vcpu_reg
+	ld	\tmp_reg, (PACA_EXMC+\offset)(r13)
+	std	\tmp_reg, VCPU_GPR(\src_reg)(\vcpu_reg)
+.endm
+
+.macro DISABLE_INTERRUPTS
+       mfmsr   r0
+       rldicl  r0,r0,48,1
+       rotldi  r0,r0,16
+       mtmsrd  r0,1
+.endm
+
+/*****************************************************************************
+ *                                                                           *
+ *     Guest entry / exit code that is in kernel module memory (highmem)     *
+ *                                                                           *
+ ****************************************************************************/
+
+/* Registers:
+ *  r3: kvm_run pointer
+ *  r4: vcpu pointer
+ */
+_GLOBAL(__kvmppc_vcpu_entry)
+
+kvm_start_entry:
+	/* Write correct stack frame */
+	mflr    r0
+	std     r0,16(r1)
+
+	/* Save host state to the stack */
+	stdu	r1, -SWITCH_FRAME_SIZE(r1)
+
+	/* Save r3 (kvm_run) and r4 (vcpu) */
+	SAVE_2GPRS(3, r1)
+
+	/* Save non-volatile registers (r14 - r31) */
+	SAVE_NVGPRS(r1)
+
+	/* Save LR */
+	mflr	r14
+	std	r14, _LINK(r1)
+
+/* XXX optimize non-volatile loading away */
+kvm_start_lightweight:
+
+	DISABLE_INTERRUPTS
+
+	/* Save R1/R2 in the PACA */
+	std	r1, PACAR1(r13)
+	std	r2, (PACA_EXMC+EX_SRR0)(r13)
+	ld	r3, VCPU_HIGHMEM_HANDLER(r4)
+	std	r3, PACASAVEDMSR(r13)
+
+	/* Load non-volatile guest state from the vcpu */
+	ld	r14, VCPU_GPR(r14)(r4)
+	ld	r15, VCPU_GPR(r15)(r4)
+	ld	r16, VCPU_GPR(r16)(r4)
+	ld	r17, VCPU_GPR(r17)(r4)
+	ld	r18, VCPU_GPR(r18)(r4)
+	ld	r19, VCPU_GPR(r19)(r4)
+	ld	r20, VCPU_GPR(r20)(r4)
+	ld	r21, VCPU_GPR(r21)(r4)
+	ld	r22, VCPU_GPR(r22)(r4)
+	ld	r23, VCPU_GPR(r23)(r4)
+	ld	r24, VCPU_GPR(r24)(r4)
+	ld	r25, VCPU_GPR(r25)(r4)
+	ld	r26, VCPU_GPR(r26)(r4)
+	ld	r27, VCPU_GPR(r27)(r4)
+	ld	r28, VCPU_GPR(r28)(r4)
+	ld	r29, VCPU_GPR(r29)(r4)
+	ld	r30, VCPU_GPR(r30)(r4)
+	ld	r31, VCPU_GPR(r31)(r4)
+
+	ld	r9, VCPU_PC(r4)			/* r9 = vcpu->arch.pc */
+	ld	r10, VCPU_SHADOW_MSR(r4)	/* r10 = vcpu->arch.shadow_msr */
+
+	ld	r3, VCPU_TRAMPOLINE_ENTER(r4)
+	mtsrr0	r3
+
+	LOAD_REG_IMMEDIATE(r3, MSR_KERNEL & ~(MSR_IR | MSR_DR))
+	mtsrr1	r3
+
+	/* Load guest state in the respective registers */
+	lwz	r3, VCPU_CR(r4)		/* r3 = vcpu->arch.cr */
+	stw	r3, (PACA_EXMC + EX_CCR)(r13)
+
+	ld	r3, VCPU_CTR(r4)	/* r3 = vcpu->arch.ctr */
+	mtctr	r3			/* CTR = r3 */
+
+	ld	r3, VCPU_LR(r4)		/* r3 = vcpu->arch.lr */
+	mtlr	r3			/* LR = r3 */
+
+	ld	r3, VCPU_XER(r4)	/* r3 = vcpu->arch.xer */
+	std	r3, (PACA_EXMC + EX_R3)(r13)
+
+	/* Some guests may need to have dcbz set to 32 byte length.
+	 *
+	 * Usually we ensure that by patching the guest's instructions
+	 * to trap on dcbz and emulate it in the hypervisor.
+	 *
+	 * If we can, we should tell the CPU to use 32 byte dcbz though,
+	 * because that's a lot faster.
+	 */
+
+	ld	r3, VCPU_HFLAGS(r4)
+	rldicl.	r3, r3, 0, 63		/* CR = ((r3 & 1) == 0) */
+	beq	no_dcbz32_on
+
+	mfspr   r3,SPRN_HID5
+	ori     r3, r3, 0x80		/* XXX HID5_dcbz32 = 0x80 */
+	mtspr   SPRN_HID5,r3
+
+no_dcbz32_on:
+	/*	Load guest GPRs */
+
+	ld	r3, VCPU_GPR(r9)(r4)
+	std	r3, (PACA_EXMC + EX_R9)(r13)
+	ld	r3, VCPU_GPR(r10)(r4)
+	std	r3, (PACA_EXMC + EX_R10)(r13)
+	ld	r3, VCPU_GPR(r11)(r4)
+	std	r3, (PACA_EXMC + EX_R11)(r13)
+	ld	r3, VCPU_GPR(r12)(r4)
+	std	r3, (PACA_EXMC + EX_R12)(r13)
+	ld	r3, VCPU_GPR(r13)(r4)
+	std	r3, (PACA_EXMC + EX_R13)(r13)
+
+	ld	r0, VCPU_GPR(r0)(r4)
+	ld	r1, VCPU_GPR(r1)(r4)
+	ld	r2, VCPU_GPR(r2)(r4)
+	ld	r3, VCPU_GPR(r3)(r4)
+	ld	r5, VCPU_GPR(r5)(r4)
+	ld	r6, VCPU_GPR(r6)(r4)
+	ld	r7, VCPU_GPR(r7)(r4)
+	ld	r8, VCPU_GPR(r8)(r4)
+	ld	r4, VCPU_GPR(r4)(r4)
+
+	/* This sets the Magic value for the trampoline */
+
+	li	r11, 1
+	stb	r11, PACA_KVM_IN_GUEST(r13)
+
+	/* Jump to SLB patching handlder and into our guest */
+	RFI
+
+/*
+ * This is the handler in module memory. It gets jumped at from the
+ * lowmem trampoline code, so it's basically the guest exit code.
+ *
+ */
+
+.global kvmppc_handler_highmem
+kvmppc_handler_highmem:
+
+	/*
+	 * Register usage at this point:
+	 *
+	 * R00   = guest R13
+	 * R01   = host R1
+	 * R02   = host R2
+	 * R10   = guest PC
+	 * R11   = guest MSR
+	 * R12   = exit handler id
+	 * R13   = PACA
+	 * 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
+	 * PACA.exmc.DAR   = guest DAR
+	 * PACA.exmc.DSISR = guest DSISR
+	 * PACA.exmc.LR    = guest instruction
+	 * PACA.exmc.CCR   = guest CR
+	 * PACA.exmc.SRR0  = guest R0
+	 *
+	 */
+
+	std	r3, (PACA_EXMC+EX_R3)(r13)
+
+	/* save the exit id in R3 */
+	mr	r3, r12
+
+	/* R12 = vcpu */
+	ld	r12, GPR4(r1)
+
+	/* Now save the guest state */
+
+	std	r0, VCPU_GPR(r13)(r12)
+	std	r4, VCPU_GPR(r4)(r12)
+	std	r5, VCPU_GPR(r5)(r12)
+	std	r6, VCPU_GPR(r6)(r12)
+	std	r7, VCPU_GPR(r7)(r12)
+	std	r8, VCPU_GPR(r8)(r12)
+	std	r9, VCPU_GPR(r9)(r12)
+
+	/* get registers from PACA */
+	mfpaca	r5, r0, EX_SRR0, r12
+	mfpaca	r5, r3, EX_R3, r12
+	mfpaca	r5, r1, EX_R9, r12
+	mfpaca	r5, r10, EX_R10, r12
+	mfpaca	r5, r11, EX_R11, r12
+	mfpaca	r5, r12, EX_R12, r12
+	mfpaca	r5, r2, EX_R13, r12
+
+	lwz	r5, (PACA_EXMC+EX_LR)(r13)
+	stw	r5, VCPU_LAST_INST(r12)
+
+	lwz	r5, (PACA_EXMC+EX_CCR)(r13)
+	stw	r5, VCPU_CR(r12)
+
+	ld	r5, VCPU_HFLAGS(r12)
+	rldicl.	r5, r5, 0, 63		/* CR = ((r5 & 1) == 0) */
+	beq	no_dcbz32_off
+
+	mfspr   r5,SPRN_HID5
+	rldimi  r5,r5,6,56
+	mtspr   SPRN_HID5,r5
+
+no_dcbz32_off:
+
+	/* XXX maybe skip on lightweight? */
+	std	r14, VCPU_GPR(r14)(r12)
+	std	r15, VCPU_GPR(r15)(r12)
+	std	r16, VCPU_GPR(r16)(r12)
+	std	r17, VCPU_GPR(r17)(r12)
+	std	r18, VCPU_GPR(r18)(r12)
+	std	r19, VCPU_GPR(r19)(r12)
+	std	r20, VCPU_GPR(r20)(r12)
+	std	r21, VCPU_GPR(r21)(r12)
+	std	r22, VCPU_GPR(r22)(r12)
+	std	r23, VCPU_GPR(r23)(r12)
+	std	r24, VCPU_GPR(r24)(r12)
+	std	r25, VCPU_GPR(r25)(r12)
+	std	r26, VCPU_GPR(r26)(r12)
+	std	r27, VCPU_GPR(r27)(r12)
+	std	r28, VCPU_GPR(r28)(r12)
+	std	r29, VCPU_GPR(r29)(r12)
+	std	r30, VCPU_GPR(r30)(r12)
+	std	r31, VCPU_GPR(r31)(r12)
+
+	/* Restore non-volatile host registers (r14 - r31) */
+	REST_NVGPRS(r1)
+
+	/* Save guest PC (R10) */
+	std	r10, VCPU_PC(r12)
+
+	/* Save guest msr (R11) */
+	std	r11, VCPU_SHADOW_MSR(r12)
+
+	/* Save guest CTR (in R12) */
+	mfctr	r5
+	std	r5, VCPU_CTR(r12)
+
+	/* Save guest LR */
+	mflr	r5
+	std	r5, VCPU_LR(r12)
+
+	/* Save guest XER */
+	mfxer	r5
+	std	r5, VCPU_XER(r12)
+
+	/* Save guest DAR */
+	ld	r5, (PACA_EXMC+EX_DAR)(r13)
+	std	r5, VCPU_FAULT_DEAR(r12)
+
+	/* Save guest DSISR */
+	lwz	r5, (PACA_EXMC+EX_DSISR)(r13)
+	std	r5, VCPU_FAULT_DSISR(r12)
+
+	/* Restore host msr -> SRR1 */
+	ld	r7, VCPU_HOST_MSR(r12)
+	mtsrr1	r7
+
+	/* Restore host IP -> SRR0 */
+	ld	r6, VCPU_HOST_RETIP(r12)
+	mtsrr0	r6
+
+	/*
+	 * For some interrupts, we need to call the real Linux
+	 * handler, so it can do work for us. This has to happen
+	 * as if the interrupt arrived from the kernel though,
+	 * so let's fake it here where most state is restored.
+	 *
+	 * Call Linux for hardware interrupts/decrementer
+	 * r3 = address of interrupt handler (exit reason)
+	 */
+
+	cmpwi	r3, BOOK3S_INTERRUPT_EXTERNAL
+	beq	call_linux_handler
+	cmpwi	r3, BOOK3S_INTERRUPT_DECREMENTER
+	beq	call_linux_handler
+
+	/* Back to Interruptable Mode! (goto kvm_return_point) */
+	RFI
+
+call_linux_handler:
+
+	/*
+	 * If we land here we need to jump back to the handler we
+	 * came from.
+	 *
+	 * We have a page that we can access from real mode, so let's
+	 * jump back to that and use it as a trampoline to get back into the
+	 * interrupt handler!
+	 *
+	 * R3 still contains the exit code,
+	 * R6 VCPU_HOST_RETIP and
+	 * R7 VCPU_HOST_MSR
+	 */
+
+	mtlr	r3
+
+	ld	r5, VCPU_TRAMPOLINE_LOWMEM(r12)
+	mtsrr0	r5
+	LOAD_REG_IMMEDIATE(r5, MSR_KERNEL & ~(MSR_IR | MSR_DR))
+	mtsrr1	r5
+
+	RFI
+
+.global kvm_return_point
+kvm_return_point:
+
+	/* Jump back to lightweight entry if we're supposed to */
+	/* go back into the guest */
+	mr	r5, r3
+	/* Restore r3 (kvm_run) and r4 (vcpu) */
+	REST_2GPRS(3, r1)
+	bl	KVMPPC_HANDLE_EXIT
+
+#if 0 /* XXX get lightweight exits back */
+	cmpwi	r3, RESUME_GUEST
+	bne	kvm_exit_heavyweight
+
+	/* put VCPU and KVM_RUN back into place and roll again! */
+	REST_2GPRS(3, r1)
+	b	kvm_start_lightweight
+
+kvm_exit_heavyweight:
+	/* Restore non-volatile host registers */
+	ld	r14, _LINK(r1)
+	mtlr	r14
+	REST_NVGPRS(r1)
+
+	addi    r1, r1, SWITCH_FRAME_SIZE
+#else
+	ld	r4, _LINK(r1)
+	mtlr	r4
+
+	cmpwi	r3, RESUME_GUEST
+	bne	kvm_exit_heavyweight
+
+	REST_2GPRS(3, r1)
+
+	addi    r1, r1, SWITCH_FRAME_SIZE
+
+	b	kvm_start_entry
+
+kvm_exit_heavyweight:
+
+	addi    r1, r1, SWITCH_FRAME_SIZE
+#endif
+
+	blr