From f61c94bb99ca4253ac5dd57750e1af209a4beb7a Mon Sep 17 00:00:00 2001 From: Bharat Bhushan Date: Wed, 8 Aug 2012 20:38:19 +0000 Subject: KVM: PPC: booke: Add watchdog emulation This patch adds the watchdog emulation in KVM. The watchdog emulation is enabled by KVM_ENABLE_CAP(KVM_CAP_PPC_BOOKE_WATCHDOG) ioctl. The kernel timer are used for watchdog emulation and emulates h/w watchdog state machine. On watchdog timer expiry, it exit to QEMU if TCR.WRC is non ZERO. QEMU can reset/shutdown etc depending upon how it is configured. Signed-off-by: Liu Yu Signed-off-by: Scott Wood [bharat.bhushan@freescale.com: reworked patch] Signed-off-by: Bharat Bhushan [agraf: adjust to new request framework] Signed-off-by: Alexander Graf --- arch/powerpc/kvm/booke_emulate.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'arch/powerpc/kvm/booke_emulate.c') diff --git a/arch/powerpc/kvm/booke_emulate.c b/arch/powerpc/kvm/booke_emulate.c index 12834bb608a..5a66ade7fd1 100644 --- a/arch/powerpc/kvm/booke_emulate.c +++ b/arch/powerpc/kvm/booke_emulate.c @@ -145,6 +145,14 @@ int kvmppc_booke_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, ulong spr_val) kvmppc_clr_tsr_bits(vcpu, spr_val); break; case SPRN_TCR: + /* + * WRC is a 2-bit field that is supposed to preserve its + * value once written to non-zero. + */ + if (vcpu->arch.tcr & TCR_WRC_MASK) { + spr_val &= ~TCR_WRC_MASK; + spr_val |= vcpu->arch.tcr & TCR_WRC_MASK; + } kvmppc_set_tcr(vcpu, spr_val); break; -- cgit v1.2.3-70-g09d2