1 files changed, 441 insertions, 0 deletions
diff --git a/arch/arm/kvm/interrupts_head.S b/arch/arm/kvm/interrupts_head.S
new file mode 100644
index 00000000000..6a95d341e9c
--- /dev/null
+++ b/arch/arm/kvm/interrupts_head.S
@@ -0,0 +1,441 @@
+#define VCPU_USR_REG(_reg_nr)	(VCPU_USR_REGS + (_reg_nr * 4))
+#define VCPU_USR_SP		(VCPU_USR_REG(13))
+#define VCPU_USR_LR		(VCPU_USR_REG(14))
+#define CP15_OFFSET(_cp15_reg_idx) (VCPU_CP15 + (_cp15_reg_idx * 4))
+
+/*
+ * Many of these macros need to access the VCPU structure, which is always
+ * held in r0. These macros should never clobber r1, as it is used to hold the
+ * exception code on the return path (except of course the macro that switches
+ * all the registers before the final jump to the VM).
+ */
+vcpu	.req	r0		@ vcpu pointer always in r0
+
+/* Clobbers {r2-r6} */
+.macro store_vfp_state vfp_base
+	@ The VFPFMRX and VFPFMXR macros are the VMRS and VMSR instructions
+	VFPFMRX	r2, FPEXC
+	@ Make sure VFP is enabled so we can touch the registers.
+	orr	r6, r2, #FPEXC_EN
+	VFPFMXR	FPEXC, r6
+
+	VFPFMRX	r3, FPSCR
+	tst	r2, #FPEXC_EX		@ Check for VFP Subarchitecture
+	beq	1f
+	@ If FPEXC_EX is 0, then FPINST/FPINST2 reads are upredictable, so
+	@ we only need to save them if FPEXC_EX is set.
+	VFPFMRX r4, FPINST
+	tst	r2, #FPEXC_FP2V
+	VFPFMRX r5, FPINST2, ne		@ vmrsne
+	bic	r6, r2, #FPEXC_EX	@ FPEXC_EX disable
+	VFPFMXR	FPEXC, r6
+1:
+	VFPFSTMIA \vfp_base, r6		@ Save VFP registers
+	stm	\vfp_base, {r2-r5}	@ Save FPEXC, FPSCR, FPINST, FPINST2
+.endm
+
+/* Assume FPEXC_EN is on and FPEXC_EX is off, clobbers {r2-r6} */
+.macro restore_vfp_state vfp_base
+	VFPFLDMIA \vfp_base, r6		@ Load VFP registers
+	ldm	\vfp_base, {r2-r5}	@ Load FPEXC, FPSCR, FPINST, FPINST2
+
+	VFPFMXR FPSCR, r3
+	tst	r2, #FPEXC_EX		@ Check for VFP Subarchitecture
+	beq	1f
+	VFPFMXR FPINST, r4
+	tst	r2, #FPEXC_FP2V
+	VFPFMXR FPINST2, r5, ne
+1:
+	VFPFMXR FPEXC, r2	@ FPEXC	(last, in case !EN)
+.endm
+
+/* These are simply for the macros to work - value don't have meaning */
+.equ usr, 0
+.equ svc, 1
+.equ abt, 2
+.equ und, 3
+.equ irq, 4
+.equ fiq, 5
+
+.macro push_host_regs_mode mode
+	mrs	r2, SP_\mode
+	mrs	r3, LR_\mode
+	mrs	r4, SPSR_\mode
+	push	{r2, r3, r4}
+.endm
+
+/*
+ * Store all host persistent registers on the stack.
+ * Clobbers all registers, in all modes, except r0 and r1.
+ */
+.macro save_host_regs
+	/* Hyp regs. Only ELR_hyp (SPSR_hyp already saved) */
+	mrs	r2, ELR_hyp
+	push	{r2}
+
+	/* usr regs */
+	push	{r4-r12}	@ r0-r3 are always clobbered
+	mrs	r2, SP_usr
+	mov	r3, lr
+	push	{r2, r3}
+
+	push_host_regs_mode svc
+	push_host_regs_mode abt
+	push_host_regs_mode und
+	push_host_regs_mode irq
+
+	/* fiq regs */
+	mrs	r2, r8_fiq
+	mrs	r3, r9_fiq
+	mrs	r4, r10_fiq
+	mrs	r5, r11_fiq
+	mrs	r6, r12_fiq
+	mrs	r7, SP_fiq
+	mrs	r8, LR_fiq
+	mrs	r9, SPSR_fiq
+	push	{r2-r9}
+.endm
+
+.macro pop_host_regs_mode mode
+	pop	{r2, r3, r4}
+	msr	SP_\mode, r2
+	msr	LR_\mode, r3
+	msr	SPSR_\mode, r4
+.endm
+
+/*
+ * Restore all host registers from the stack.
+ * Clobbers all registers, in all modes, except r0 and r1.
+ */
+.macro restore_host_regs
+	pop	{r2-r9}
+	msr	r8_fiq, r2
+	msr	r9_fiq, r3
+	msr	r10_fiq, r4
+	msr	r11_fiq, r5
+	msr	r12_fiq, r6
+	msr	SP_fiq, r7
+	msr	LR_fiq, r8
+	msr	SPSR_fiq, r9
+
+	pop_host_regs_mode irq
+	pop_host_regs_mode und
+	pop_host_regs_mode abt
+	pop_host_regs_mode svc
+
+	pop	{r2, r3}
+	msr	SP_usr, r2
+	mov	lr, r3
+	pop	{r4-r12}
+
+	pop	{r2}
+	msr	ELR_hyp, r2
+.endm
+
+/*
+ * Restore SP, LR and SPSR for a given mode. offset is the offset of
+ * this mode's registers from the VCPU base.
+ *
+ * Assumes vcpu pointer in vcpu reg
+ *
+ * Clobbers r1, r2, r3, r4.
+ */
+.macro restore_guest_regs_mode mode, offset
+	add	r1, vcpu, \offset
+	ldm	r1, {r2, r3, r4}
+	msr	SP_\mode, r2
+	msr	LR_\mode, r3
+	msr	SPSR_\mode, r4
+.endm
+
+/*
+ * Restore all guest registers from the vcpu struct.
+ *
+ * Assumes vcpu pointer in vcpu reg
+ *
+ * Clobbers *all* registers.
+ */
+.macro restore_guest_regs
+	restore_guest_regs_mode svc, #VCPU_SVC_REGS
+	restore_guest_regs_mode abt, #VCPU_ABT_REGS
+	restore_guest_regs_mode und, #VCPU_UND_REGS
+	restore_guest_regs_mode irq, #VCPU_IRQ_REGS
+
+	add	r1, vcpu, #VCPU_FIQ_REGS
+	ldm	r1, {r2-r9}
+	msr	r8_fiq, r2
+	msr	r9_fiq, r3
+	msr	r10_fiq, r4
+	msr	r11_fiq, r5
+	msr	r12_fiq, r6
+	msr	SP_fiq, r7
+	msr	LR_fiq, r8
+	msr	SPSR_fiq, r9
+
+	@ Load return state
+	ldr	r2, [vcpu, #VCPU_PC]
+	ldr	r3, [vcpu, #VCPU_CPSR]
+	msr	ELR_hyp, r2
+	msr	SPSR_cxsf, r3
+
+	@ Load user registers
+	ldr	r2, [vcpu, #VCPU_USR_SP]
+	ldr	r3, [vcpu, #VCPU_USR_LR]
+	msr	SP_usr, r2
+	mov	lr, r3
+	add	vcpu, vcpu, #(VCPU_USR_REGS)
+	ldm	vcpu, {r0-r12}
+.endm
+
+/*
+ * Save SP, LR and SPSR for a given mode. offset is the offset of
+ * this mode's registers from the VCPU base.
+ *
+ * Assumes vcpu pointer in vcpu reg
+ *
+ * Clobbers r2, r3, r4, r5.
+ */
+.macro save_guest_regs_mode mode, offset
+	add	r2, vcpu, \offset
+	mrs	r3, SP_\mode
+	mrs	r4, LR_\mode
+	mrs	r5, SPSR_\mode
+	stm	r2, {r3, r4, r5}
+.endm
+
+/*
+ * Save all guest registers to the vcpu struct
+ * Expects guest's r0, r1, r2 on the stack.
+ *
+ * Assumes vcpu pointer in vcpu reg
+ *
+ * Clobbers r2, r3, r4, r5.
+ */
+.macro save_guest_regs
+	@ Store usr registers
+	add	r2, vcpu, #VCPU_USR_REG(3)
+	stm	r2, {r3-r12}
+	add	r2, vcpu, #VCPU_USR_REG(0)
+	pop	{r3, r4, r5}		@ r0, r1, r2
+	stm	r2, {r3, r4, r5}
+	mrs	r2, SP_usr
+	mov	r3, lr
+	str	r2, [vcpu, #VCPU_USR_SP]
+	str	r3, [vcpu, #VCPU_USR_LR]
+
+	@ Store return state
+	mrs	r2, ELR_hyp
+	mrs	r3, spsr
+	str	r2, [vcpu, #VCPU_PC]
+	str	r3, [vcpu, #VCPU_CPSR]
+
+	@ Store other guest registers
+	save_guest_regs_mode svc, #VCPU_SVC_REGS
+	save_guest_regs_mode abt, #VCPU_ABT_REGS
+	save_guest_regs_mode und, #VCPU_UND_REGS
+	save_guest_regs_mode irq, #VCPU_IRQ_REGS
+.endm
+
+/* Reads cp15 registers from hardware and stores them in memory
+ * @store_to_vcpu: If 0, registers are written in-order to the stack,
+ * 		   otherwise to the VCPU struct pointed to by vcpup
+ *
+ * Assumes vcpu pointer in vcpu reg
+ *
+ * Clobbers r2 - r12
+ */
+.macro read_cp15_state store_to_vcpu
+	mrc	p15, 0, r2, c1, c0, 0	@ SCTLR
+	mrc	p15, 0, r3, c1, c0, 2	@ CPACR
+	mrc	p15, 0, r4, c2, c0, 2	@ TTBCR
+	mrc	p15, 0, r5, c3, c0, 0	@ DACR
+	mrrc	p15, 0, r6, r7, c2	@ TTBR 0
+	mrrc	p15, 1, r8, r9, c2	@ TTBR 1
+	mrc	p15, 0, r10, c10, c2, 0	@ PRRR
+	mrc	p15, 0, r11, c10, c2, 1	@ NMRR
+	mrc	p15, 2, r12, c0, c0, 0	@ CSSELR
+
+	.if \store_to_vcpu == 0
+	push	{r2-r12}		@ Push CP15 registers
+	.else
+	str	r2, [vcpu, #CP15_OFFSET(c1_SCTLR)]
+	str	r3, [vcpu, #CP15_OFFSET(c1_CPACR)]
+	str	r4, [vcpu, #CP15_OFFSET(c2_TTBCR)]
+	str	r5, [vcpu, #CP15_OFFSET(c3_DACR)]
+	add	r2, vcpu, #CP15_OFFSET(c2_TTBR0)
+	strd	r6, r7, [r2]
+	add	r2, vcpu, #CP15_OFFSET(c2_TTBR1)
+	strd	r8, r9, [r2]
+	str	r10, [vcpu, #CP15_OFFSET(c10_PRRR)]
+	str	r11, [vcpu, #CP15_OFFSET(c10_NMRR)]
+	str	r12, [vcpu, #CP15_OFFSET(c0_CSSELR)]
+	.endif
+
+	mrc	p15, 0, r2, c13, c0, 1	@ CID
+	mrc	p15, 0, r3, c13, c0, 2	@ TID_URW
+	mrc	p15, 0, r4, c13, c0, 3	@ TID_URO
+	mrc	p15, 0, r5, c13, c0, 4	@ TID_PRIV
+	mrc	p15, 0, r6, c5, c0, 0	@ DFSR
+	mrc	p15, 0, r7, c5, c0, 1	@ IFSR
+	mrc	p15, 0, r8, c5, c1, 0	@ ADFSR
+	mrc	p15, 0, r9, c5, c1, 1	@ AIFSR
+	mrc	p15, 0, r10, c6, c0, 0	@ DFAR
+	mrc	p15, 0, r11, c6, c0, 2	@ IFAR
+	mrc	p15, 0, r12, c12, c0, 0	@ VBAR
+
+	.if \store_to_vcpu == 0
+	push	{r2-r12}		@ Push CP15 registers
+	.else
+	str	r2, [vcpu, #CP15_OFFSET(c13_CID)]
+	str	r3, [vcpu, #CP15_OFFSET(c13_TID_URW)]
+	str	r4, [vcpu, #CP15_OFFSET(c13_TID_URO)]
+	str	r5, [vcpu, #CP15_OFFSET(c13_TID_PRIV)]
+	str	r6, [vcpu, #CP15_OFFSET(c5_DFSR)]
+	str	r7, [vcpu, #CP15_OFFSET(c5_IFSR)]
+	str	r8, [vcpu, #CP15_OFFSET(c5_ADFSR)]
+	str	r9, [vcpu, #CP15_OFFSET(c5_AIFSR)]
+	str	r10, [vcpu, #CP15_OFFSET(c6_DFAR)]
+	str	r11, [vcpu, #CP15_OFFSET(c6_IFAR)]
+	str	r12, [vcpu, #CP15_OFFSET(c12_VBAR)]
+	.endif
+.endm
+
+/*
+ * Reads cp15 registers from memory and writes them to hardware
+ * @read_from_vcpu: If 0, registers are read in-order from the stack,
+ *		    otherwise from the VCPU struct pointed to by vcpup
+ *
+ * Assumes vcpu pointer in vcpu reg
+ */
+.macro write_cp15_state read_from_vcpu
+	.if \read_from_vcpu == 0
+	pop	{r2-r12}
+	.else
+	ldr	r2, [vcpu, #CP15_OFFSET(c13_CID)]
+	ldr	r3, [vcpu, #CP15_OFFSET(c13_TID_URW)]
+	ldr	r4, [vcpu, #CP15_OFFSET(c13_TID_URO)]
+	ldr	r5, [vcpu, #CP15_OFFSET(c13_TID_PRIV)]
+	ldr	r6, [vcpu, #CP15_OFFSET(c5_DFSR)]
+	ldr	r7, [vcpu, #CP15_OFFSET(c5_IFSR)]
+	ldr	r8, [vcpu, #CP15_OFFSET(c5_ADFSR)]
+	ldr	r9, [vcpu, #CP15_OFFSET(c5_AIFSR)]
+	ldr	r10, [vcpu, #CP15_OFFSET(c6_DFAR)]
+	ldr	r11, [vcpu, #CP15_OFFSET(c6_IFAR)]
+	ldr	r12, [vcpu, #CP15_OFFSET(c12_VBAR)]
+	.endif
+
+	mcr	p15, 0, r2, c13, c0, 1	@ CID
+	mcr	p15, 0, r3, c13, c0, 2	@ TID_URW
+	mcr	p15, 0, r4, c13, c0, 3	@ TID_URO
+	mcr	p15, 0, r5, c13, c0, 4	@ TID_PRIV
+	mcr	p15, 0, r6, c5, c0, 0	@ DFSR
+	mcr	p15, 0, r7, c5, c0, 1	@ IFSR
+	mcr	p15, 0, r8, c5, c1, 0	@ ADFSR
+	mcr	p15, 0, r9, c5, c1, 1	@ AIFSR
+	mcr	p15, 0, r10, c6, c0, 0	@ DFAR
+	mcr	p15, 0, r11, c6, c0, 2	@ IFAR
+	mcr	p15, 0, r12, c12, c0, 0	@ VBAR
+
+	.if \read_from_vcpu == 0
+	pop	{r2-r12}
+	.else
+	ldr	r2, [vcpu, #CP15_OFFSET(c1_SCTLR)]
+	ldr	r3, [vcpu, #CP15_OFFSET(c1_CPACR)]
+	ldr	r4, [vcpu, #CP15_OFFSET(c2_TTBCR)]
+	ldr	r5, [vcpu, #CP15_OFFSET(c3_DACR)]
+	add	r12, vcpu, #CP15_OFFSET(c2_TTBR0)
+	ldrd	r6, r7, [r12]
+	add	r12, vcpu, #CP15_OFFSET(c2_TTBR1)
+	ldrd	r8, r9, [r12]
+	ldr	r10, [vcpu, #CP15_OFFSET(c10_PRRR)]
+	ldr	r11, [vcpu, #CP15_OFFSET(c10_NMRR)]
+	ldr	r12, [vcpu, #CP15_OFFSET(c0_CSSELR)]
+	.endif
+
+	mcr	p15, 0, r2, c1, c0, 0	@ SCTLR
+	mcr	p15, 0, r3, c1, c0, 2	@ CPACR
+	mcr	p15, 0, r4, c2, c0, 2	@ TTBCR
+	mcr	p15, 0, r5, c3, c0, 0	@ DACR
+	mcrr	p15, 0, r6, r7, c2	@ TTBR 0
+	mcrr	p15, 1, r8, r9, c2	@ TTBR 1
+	mcr	p15, 0, r10, c10, c2, 0	@ PRRR
+	mcr	p15, 0, r11, c10, c2, 1	@ NMRR
+	mcr	p15, 2, r12, c0, c0, 0	@ CSSELR
+.endm
+
+/*
+ * Save the VGIC CPU state into memory
+ *
+ * Assumes vcpu pointer in vcpu reg
+ */
+.macro save_vgic_state
+.endm
+
+/*
+ * Restore the VGIC CPU state from memory
+ *
+ * Assumes vcpu pointer in vcpu reg
+ */
+.macro restore_vgic_state
+.endm
+
+.equ vmentry,	0
+.equ vmexit,	1
+
+/* Configures the HSTR (Hyp System Trap Register) on entry/return
+ * (hardware reset value is 0) */
+.macro set_hstr operation
+	mrc	p15, 4, r2, c1, c1, 3
+	ldr	r3, =HSTR_T(15)
+	.if \operation == vmentry
+	orr	r2, r2, r3		@ Trap CR{15}
+	.else
+	bic	r2, r2, r3		@ Don't trap any CRx accesses
+	.endif
+	mcr	p15, 4, r2, c1, c1, 3
+.endm
+
+/* Configures the HCPTR (Hyp Coprocessor Trap Register) on entry/return
+ * (hardware reset value is 0). Keep previous value in r2. */
+.macro set_hcptr operation, mask
+	mrc	p15, 4, r2, c1, c1, 2
+	ldr	r3, =\mask
+	.if \operation == vmentry
+	orr	r3, r2, r3		@ Trap coproc-accesses defined in mask
+	.else
+	bic	r3, r2, r3		@ Don't trap defined coproc-accesses
+	.endif
+	mcr	p15, 4, r3, c1, c1, 2
+.endm
+
+/* Configures the HDCR (Hyp Debug Configuration Register) on entry/return
+ * (hardware reset value is 0) */
+.macro set_hdcr operation
+	mrc	p15, 4, r2, c1, c1, 1
+	ldr	r3, =(HDCR_TPM|HDCR_TPMCR)
+	.if \operation == vmentry
+	orr	r2, r2, r3		@ Trap some perfmon accesses
+	.else
+	bic	r2, r2, r3		@ Don't trap any perfmon accesses
+	.endif
+	mcr	p15, 4, r2, c1, c1, 1
+.endm
+
+/* Enable/Disable: stage-2 trans., trap interrupts, trap wfi, trap smc */
+.macro configure_hyp_role operation
+	mrc	p15, 4, r2, c1, c1, 0	@ HCR
+	bic	r2, r2, #HCR_VIRT_EXCP_MASK
+	ldr	r3, =HCR_GUEST_MASK
+	.if \operation == vmentry
+	orr	r2, r2, r3
+	ldr	r3, [vcpu, #VCPU_IRQ_LINES]
+	orr	r2, r2, r3
+	.else
+	bic	r2, r2, r3
+	.endif
+	mcr	p15, 4, r2, c1, c1, 0
+.endm
+
+.macro load_vcpu
+	mrc	p15, 4, vcpu, c13, c0, 2	@ HTPIDR
+.endm