KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller

This patch makes KVM capable of using the XIVE interrupt controller
to provide the standard PAPR "XICS" style hypercalls. It is necessary
for proper operations when the host uses XIVE natively.

This has been lightly tested on an actual system, including PCI
pass-through with a TG3 device.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Cleanup pr_xxx(), unsplit pr_xxx() strings, etc., fix build
 failures by adding KVM_XIVE which depends on KVM_XICS and XIVE, and
 adding empty stubs for the kvm_xive_xxx() routines, fixup subject,
 integrate fixes from Paul for building PR=y HV=n]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 60 insertions, 2 deletions

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 7c6477d1840a..bdb3f76ceb6b 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -30,6 +30,7 @@
 #include <asm/book3s/64/mmu-hash.h>
 #include <asm/tm.h>
 #include <asm/opal.h>
+#include <asm/xive-regs.h>
 
 #define VCPU_GPRS_TM(reg) (((reg) * ULONG_SIZE) + VCPU_GPR_TM)
 
@@ -970,6 +971,23 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 	cmpwi	r3, 512		/* 1 microsecond */
 	blt	hdec_soon
 
+#ifdef CONFIG_KVM_XICS
+	/* We are entering the guest on that thread, push VCPU to XIVE */
+	ld	r10, HSTATE_XIVE_TIMA_PHYS(r13)
+	cmpldi	cr0, r10, r0
+	beq	no_xive
+	ld	r11, VCPU_XIVE_SAVED_STATE(r4)
+	li	r9, TM_QW1_OS
+	stdcix	r11,r9,r10
+	eieio
+	lwz	r11, VCPU_XIVE_CAM_WORD(r4)
+	li	r9, TM_QW1_OS + TM_WORD2
+	stwcix	r11,r9,r10
+	li	r9, 1
+	stw	r9, VCPU_XIVE_PUSHED(r4)
+no_xive:
+#endif /* CONFIG_KVM_XICS */
+
 deliver_guest_interrupt:
 	ld	r6, VCPU_CTR(r4)
 	ld	r7, VCPU_XER(r4)
@@ -1307,6 +1325,42 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	blt	deliver_guest_interrupt
 
 guest_exit_cont:		/* r9 = vcpu, r12 = trap, r13 = paca */
+#ifdef CONFIG_KVM_XICS
+	/* We are exiting, pull the VP from the XIVE */
+	lwz	r0, VCPU_XIVE_PUSHED(r9)
+	cmpwi	cr0, r0, 0
+	beq	1f
+	li	r7, TM_SPC_PULL_OS_CTX
+	li	r6, TM_QW1_OS
+	mfmsr	r0
+	andi.	r0, r0, MSR_IR		/* in real mode? */
+	beq	2f
+	ld	r10, HSTATE_XIVE_TIMA_VIRT(r13)
+	cmpldi	cr0, r10, 0
+	beq	1f
+	/* First load to pull the context, we ignore the value */
+	lwzx	r11, r7, r10
+	eieio
+	/* Second load to recover the context state (Words 0 and 1) */
+	ldx	r11, r6, r10
+	b	3f
+2:	ld	r10, HSTATE_XIVE_TIMA_PHYS(r13)
+	cmpldi	cr0, r10, 0
+	beq	1f
+	/* First load to pull the context, we ignore the value */
+	lwzcix	r11, r7, r10
+	eieio
+	/* Second load to recover the context state (Words 0 and 1) */
+	ldcix	r11, r6, r10
+3:	std	r11, VCPU_XIVE_SAVED_STATE(r9)
+	/* Fixup some of the state for the next load */
+	li	r10, 0
+	li	r0, 0xff
+	stw	r10, VCPU_XIVE_PUSHED(r9)
+	stb	r10, (VCPU_XIVE_SAVED_STATE+3)(r9)
+	stb	r0, (VCPU_XIVE_SAVED_STATE+4)(r9)
+1:
+#endif /* CONFIG_KVM_XICS */
 	/* Save more register state  */
 	mfdar	r6
 	mfdsisr	r7
@@ -2011,7 +2065,7 @@ hcall_real_table:
 	.long	DOTSYM(kvmppc_rm_h_eoi) - hcall_real_table
 	.long	DOTSYM(kvmppc_rm_h_cppr) - hcall_real_table
 	.long	DOTSYM(kvmppc_rm_h_ipi) - hcall_real_table
-	.long	0		/* 0x70 - H_IPOLL */
+	.long	DOTSYM(kvmppc_rm_h_ipoll) - hcall_real_table
 	.long	DOTSYM(kvmppc_rm_h_xirr) - hcall_real_table
 #else
 	.long	0		/* 0x64 - H_EOI */
@@ -2181,7 +2235,11 @@ hcall_real_table:
 	.long	0		/* 0x2f0 */
 	.long	0		/* 0x2f4 */
 	.long	0		/* 0x2f8 */
-	.long	0		/* 0x2fc */
+#ifdef CONFIG_KVM_XICS
+	.long	DOTSYM(kvmppc_rm_h_xirr_x) - hcall_real_table
+#else
+	.long	0		/* 0x2fc - H_XIRR_X*/
+#endif
 	.long	DOTSYM(kvmppc_h_random) - hcall_real_table
 	.globl	hcall_real_table_end
 hcall_real_table_end: