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>

5 files changed, 14 insertions, 50 deletions

diff --git a/arch/powerpc/include/asm/kvm_book3s_asm.h b/arch/powerpc/include/asm/kvm_book3s_asm.h
index 83596f32f50b..7cea76f11c26 100644
--- a/arch/powerpc/include/asm/kvm_book3s_asm.h
+++ b/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;
diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S
index 1125c9be9e06..175d49f468af 100644
--- a/arch/powerpc/kernel/idle_book3s.S
+++ b/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() */
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 362fbd972f76..9634425f0f39 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/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)
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 985bdc0ba1c1..fd2583ddc9a9 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/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
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 3480faaf1ef8..a3746b98ec11 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/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;