Merge remote-tracking branch 'remotes/powerpc/topic/ppc-kvm' into kvm-ppc-next

This merges in the ppc-kvm topic branch of the powerpc tree to get the
commit that reverts the patch "KVM: PPC: Book3S HV: POWER9 does not
require secondary thread management".  This is needed for subsequent
patches which will be applied on this branch.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

arch/powerpc/include/asm/kvm_book3s_asm.h

@@ -104,10 +104,6 @@ struct kvmppc_host_state {
 	u8 napping;
 
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
-	/*
-	 * hwthread_req/hwthread_state pair is used to pull sibling threads
-	 * out of guest on pre-ISAv3.0B CPUs where threads share MMU.
-	 */
 	u8 hwthread_req;
 	u8 hwthread_state;
 	u8 host_ipi;

arch/powerpc/kernel/idle_book3s.S

@@ -319,20 +319,13 @@ enter_winkle:
 /*
  * r3 - PSSCR value corresponding to the requested stop state.
  */
+power_enter_stop:
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
-power_enter_stop_kvm_rm:
-	/*
-	 * This is currently unused because POWER9 KVM does not have to
-	 * gather secondary threads into sibling mode, but the code is
-	 * here in case that function is required.
-	 *
-	 * Tell KVM we're entering idle.
-	 */
+	/* Tell KVM we're entering idle */
 	li	r4,KVM_HWTHREAD_IN_IDLE
 	/* DO THIS IN REAL MODE!  See comment above. */
 	stb	r4,HSTATE_HWTHREAD_STATE(r13)
 #endif
-power_enter_stop:
 /*
  * Check if we are executing the lite variant with ESL=EC=0
  */
@@ -496,18 +489,6 @@ pnv_powersave_wakeup_mce:
 
 	b	pnv_powersave_wakeup
 
-#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
-kvm_start_guest_check:
-	li	r0,KVM_HWTHREAD_IN_KERNEL
-	stb	r0,HSTATE_HWTHREAD_STATE(r13)
-	/* Order setting hwthread_state vs. testing hwthread_req */
-	sync
-	lbz	r0,HSTATE_HWTHREAD_REQ(r13)
-	cmpwi	r0,0
-	beqlr
-	b	kvm_start_guest
-#endif
-
 /*
  * Called from reset vector for powersave wakeups.
  * cr3 - set to gt if waking up with partial/complete hypervisor state loss
@@ -532,9 +513,15 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300)
 	mr	r3,r12
 
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
-BEGIN_FTR_SECTION
-	bl	kvm_start_guest_check
-END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
+	li	r0,KVM_HWTHREAD_IN_KERNEL
+	stb	r0,HSTATE_HWTHREAD_STATE(r13)
+	/* Order setting hwthread_state vs. testing hwthread_req */
+	sync
+	lbz	r0,HSTATE_HWTHREAD_REQ(r13)
+	cmpwi	r0,0
+	beq	1f
+	b	kvm_start_guest
+1:
 #endif
 
 	/* Return SRR1 from power7_nap() */

arch/powerpc/kvm/book3s_hv.c

@@ -2118,15 +2118,6 @@ static int kvmppc_grab_hwthread(int cpu)
 	struct paca_struct *tpaca;
 	long timeout = 10000;
 
-	/*
-	 * ISA v3.0 idle routines do not set hwthread_state or test
-	 * hwthread_req, so they can not grab idle threads.
-	 */
-	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
-		WARN(1, "KVM: can not control sibling threads\n");
-		return -EBUSY;
-	}
-
 	tpaca = &paca[cpu];
 
 	/* Ensure the thread won't go into the kernel if it wakes */
@@ -2161,12 +2152,10 @@ static void kvmppc_release_hwthread(int cpu)
 	struct paca_struct *tpaca;
 
 	tpaca = &paca[cpu];
+	tpaca->kvm_hstate.hwthread_req = 0;
 	tpaca->kvm_hstate.kvm_vcpu = NULL;
 	tpaca->kvm_hstate.kvm_vcore = NULL;
 	tpaca->kvm_hstate.kvm_split_mode = NULL;
-	if (!cpu_has_feature(CPU_FTR_ARCH_300))
-		tpaca->kvm_hstate.hwthread_req = 0;
-
 }
 
 static void radix_flush_cpu(struct kvm *kvm, int cpu, struct kvm_vcpu *vcpu)

arch/powerpc/kvm/book3s_hv_rmhandlers.S

@@ -150,11 +150,9 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	subf	r4, r4, r3
 	mtspr	SPRN_DEC, r4
 
-BEGIN_FTR_SECTION
 	/* hwthread_req may have got set by cede or no vcpu, so clear it */
 	li	r0, 0
 	stb	r0, HSTATE_HWTHREAD_REQ(r13)
-END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 
 	/*
 	 * For external interrupts we need to call the Linux
@@ -317,7 +315,6 @@ kvm_novcpu_exit:
  * Relocation is off and most register values are lost.
  * r13 points to the PACA.
  * r3 contains the SRR1 wakeup value, SRR1 is trashed.
- * This is not used by ISAv3.0B processors.
  */
 	.globl	kvm_start_guest
 kvm_start_guest:
@@ -436,9 +433,6 @@ kvm_secondary_got_guest:
  * While waiting we also need to check if we get given a vcpu to run.
  */
 kvm_no_guest:
-BEGIN_FTR_SECTION
-	twi	31,0,0
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	lbz	r3, HSTATE_HWTHREAD_REQ(r13)
 	cmpwi	r3, 0
 	bne	53f
@@ -2544,10 +2538,8 @@ kvm_do_nap:
 	clrrdi	r0, r0, 1
 	mtspr	SPRN_CTRLT, r0
 
-BEGIN_FTR_SECTION
 	li	r0,1
 	stb	r0,HSTATE_HWTHREAD_REQ(r13)
-END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 	mfspr	r5,SPRN_LPCR
 	ori	r5,r5,LPCR_PECE0 | LPCR_PECE1
 BEGIN_FTR_SECTION

arch/powerpc/kvm/powerpc.c

@@ -644,8 +644,8 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 		break;
 #endif
 	case KVM_CAP_PPC_HTM:
-		r = cpu_has_feature(CPU_FTR_TM_COMP) &&
-		    is_kvmppc_hv_enabled(kvm);
+		r = is_kvmppc_hv_enabled(kvm) &&
+		    (cur_cpu_spec->cpu_user_features2 & PPC_FEATURE2_HTM_COMP);
 		break;
 	default:
 		r = 0;