1 files changed, 116 insertions, 1 deletions

diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index 90644db9d38e..49a2c7825e04 100644
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -278,7 +278,8 @@ void kvmhv_commence_exit(int trap)
         struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore;
         int ptid = local_paca->kvm_hstate.ptid;
         struct kvm_split_mode *sip = local_paca->kvm_hstate.kvm_split_mode;
-        int me, ee, i;
+        int me, ee, i, t;
+        int cpu0;
 
         /* Set our bit in the threads-exiting-guest map in the 0xff00
            bits of vcore->entry_exit_map */
@@ -320,6 +321,22 @@ void kvmhv_commence_exit(int trap)
                 if ((ee >> 8) == 0)
                         kvmhv_interrupt_vcore(vc, ee);
         }
+
+        /*
+         * On POWER9 when running a HPT guest on a radix host (sip != NULL),
+         * we have to interrupt inactive CPU threads to get them to
+         * restore the host LPCR value.
+         */
+        if (sip->lpcr_req) {
+                if (cmpxchg(&sip->do_restore, 0, 1) == 0) {
+                        vc = local_paca->kvm_hstate.kvm_vcore;
+                        cpu0 = vc->pcpu + ptid - local_paca->kvm_hstate.tid;
+                        for (t = 1; t < threads_per_core; ++t) {
+                                if (sip->napped[t])
+                                        kvmhv_rm_send_ipi(cpu0 + t);
+                        }
+                }
+        }
 }
 
 struct kvmppc_host_rm_ops *kvmppc_host_rm_ops_hv;
@@ -529,6 +546,8 @@ static inline bool is_rm(void)
 
 unsigned long kvmppc_rm_h_xirr(struct kvm_vcpu *vcpu)
 {
+        if (!kvmppc_xics_enabled(vcpu))
+                return H_TOO_HARD;
         if (xive_enabled()) {
                 if (is_rm())
                         return xive_rm_h_xirr(vcpu);
@@ -541,6 +560,8 @@ unsigned long kvmppc_rm_h_xirr(struct kvm_vcpu *vcpu)
 
 unsigned long kvmppc_rm_h_xirr_x(struct kvm_vcpu *vcpu)
 {
+        if (!kvmppc_xics_enabled(vcpu))
+                return H_TOO_HARD;
         vcpu->arch.gpr[5] = get_tb();
         if (xive_enabled()) {
                 if (is_rm())
@@ -554,6 +575,8 @@ unsigned long kvmppc_rm_h_xirr_x(struct kvm_vcpu *vcpu)
 
 unsigned long kvmppc_rm_h_ipoll(struct kvm_vcpu *vcpu, unsigned long server)
 {
+        if (!kvmppc_xics_enabled(vcpu))
+                return H_TOO_HARD;
         if (xive_enabled()) {
                 if (is_rm())
                         return xive_rm_h_ipoll(vcpu, server);
@@ -567,6 +590,8 @@ unsigned long kvmppc_rm_h_ipoll(struct kvm_vcpu *vcpu, unsigned long server)
 int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
                     unsigned long mfrr)
 {
+        if (!kvmppc_xics_enabled(vcpu))
+                return H_TOO_HARD;
         if (xive_enabled()) {
                 if (is_rm())
                         return xive_rm_h_ipi(vcpu, server, mfrr);
@@ -579,6 +604,8 @@ int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
 
 int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr)
 {
+        if (!kvmppc_xics_enabled(vcpu))
+                return H_TOO_HARD;
         if (xive_enabled()) {
                 if (is_rm())
                         return xive_rm_h_cppr(vcpu, cppr);
@@ -591,6 +618,8 @@ int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr)
 
 int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr)
 {
+        if (!kvmppc_xics_enabled(vcpu))
+                return H_TOO_HARD;
         if (xive_enabled()) {
                 if (is_rm())
                         return xive_rm_h_eoi(vcpu, xirr);
@@ -601,3 +630,89 @@ int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr)
                 return xics_rm_h_eoi(vcpu, xirr);
 }
 #endif /* CONFIG_KVM_XICS */
+
+void kvmppc_bad_interrupt(struct pt_regs *regs)
+{
+        die("Bad interrupt in KVM entry/exit code", regs, SIGABRT);
+        panic("Bad KVM trap");
+}
+
+/*
+ * Functions used to switch LPCR HR and UPRT bits on all threads
+ * when entering and exiting HPT guests on a radix host.
+ */
+
+#define PHASE_REALMODE          1       /* in real mode */
+#define PHASE_SET_LPCR          2       /* have set LPCR */
+#define PHASE_OUT_OF_GUEST      4       /* have finished executing in guest */
+#define PHASE_RESET_LPCR        8       /* have reset LPCR to host value */
+
+#define ALL(p)          (((p) << 24) | ((p) << 16) | ((p) << 8) | (p))
+
+static void wait_for_sync(struct kvm_split_mode *sip, int phase)
+{
+        int thr = local_paca->kvm_hstate.tid;
+
+        sip->lpcr_sync.phase[thr] |= phase;
+        phase = ALL(phase);
+        while ((sip->lpcr_sync.allphases & phase) != phase) {
+                HMT_low();
+                barrier();
+        }
+        HMT_medium();
+}
+
+void kvmhv_p9_set_lpcr(struct kvm_split_mode *sip)
+{
+        unsigned long rb, set;
+
+        /* wait for every other thread to get to real mode */
+        wait_for_sync(sip, PHASE_REALMODE);
+
+        /* Set LPCR and LPIDR */
+        mtspr(SPRN_LPCR, sip->lpcr_req);
+        mtspr(SPRN_LPID, sip->lpidr_req);
+        isync();
+
+        /* Invalidate the TLB on thread 0 */
+        if (local_paca->kvm_hstate.tid == 0) {
+                sip->do_set = 0;
+                asm volatile("ptesync" : : : "memory");
+                for (set = 0; set < POWER9_TLB_SETS_RADIX; ++set) {
+                        rb = TLBIEL_INVAL_SET_LPID +
+                                (set << TLBIEL_INVAL_SET_SHIFT);
+                        asm volatile(PPC_TLBIEL(%0, %1, 0, 0, 0) : :
+                                     "r" (rb), "r" (0));
+                }
+                asm volatile("ptesync" : : : "memory");
+        }
+
+        /* indicate that we have done so and wait for others */
+        wait_for_sync(sip, PHASE_SET_LPCR);
+        /* order read of sip->lpcr_sync.allphases vs. sip->do_set */
+        smp_rmb();
+}
+
+/*
+ * Called when a thread that has been in the guest needs
+ * to reload the host LPCR value - but only on POWER9 when
+ * running a HPT guest on a radix host.
+ */
+void kvmhv_p9_restore_lpcr(struct kvm_split_mode *sip)
+{
+        /* we're out of the guest... */
+        wait_for_sync(sip, PHASE_OUT_OF_GUEST);
+
+        mtspr(SPRN_LPID, 0);
+        mtspr(SPRN_LPCR, sip->host_lpcr);
+        isync();
+
+        if (local_paca->kvm_hstate.tid == 0) {
+                sip->do_restore = 0;
+                smp_wmb();      /* order store of do_restore vs. phase */
+        }
+
+        wait_for_sync(sip, PHASE_RESET_LPCR);
+        smp_mb();
+        local_paca->kvm_hstate.kvm_split_mode = NULL;
+}