From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoffer Dall Subject: Re: [PATCH] KVM: arm: Enable emulation of the physical timer Date: Fri, 16 Feb 2018 09:13:27 +0100 Message-ID: <20180216081327.GA10440@cbox> References: <1518518476-26645-1-git-send-email-j.fanguede@virtualopensystems.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline In-Reply-To: <1518518476-26645-1-git-send-email-j.fanguede@virtualopensystems.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: =?iso-8859-1?B?Suly6W15IEZhbmd16GRl?= Cc: Marc Zyngier , linux-kernel@vger.kernel.org, Russell King , tech@virtualopensystems.com, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org List-Id: kvmarm@lists.cs.columbia.edu On Tue, Feb 13, 2018 at 11:41:16AM +0100, J=E9r=E9my Fangu=E8de wrote: > Set the handlers to emulate read and write operations for CNTP_CTL, > CNTP_CVAL and CNTP_TVAL registers in such a way that VMs can use the > physical timer. > = > Signed-off-by: J=E9r=E9my Fangu=E8de > --- > = > This patch is the equivalent of this one: [1], but for arm 32bits > instead of ARMv8 aarch32. > = > [1] https://patchwork.kernel.org/patch/10207019/ > = Thanks, both queued. -Christoffer > --- > arch/arm/kvm/coproc.c | 61 +++++++++++++++++++++++++++++++++++++++++++++= ++++++ > 1 file changed, 61 insertions(+) > = > diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c > index 6d1d2e2..3a02e76 100644 > --- a/arch/arm/kvm/coproc.c > +++ b/arch/arm/kvm/coproc.c > @@ -270,6 +270,60 @@ static bool access_gic_sre(struct kvm_vcpu *vcpu, > return true; > } > = > +static bool access_cntp_tval(struct kvm_vcpu *vcpu, > + const struct coproc_params *p, > + const struct coproc_reg *r) > +{ > + u64 now =3D kvm_phys_timer_read(); > + u64 val; > + > + if (p->is_write) { > + val =3D *vcpu_reg(vcpu, p->Rt1); > + kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL, val + now); > + } else { > + val =3D kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL); > + *vcpu_reg(vcpu, p->Rt1) =3D val - now; > + } > + > + return true; > +} > + > +static bool access_cntp_ctl(struct kvm_vcpu *vcpu, > + const struct coproc_params *p, > + const struct coproc_reg *r) > +{ > + u32 val; > + > + if (p->is_write) { > + val =3D *vcpu_reg(vcpu, p->Rt1); > + kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CTL, val); > + } else { > + val =3D kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CTL); > + *vcpu_reg(vcpu, p->Rt1) =3D val; > + } > + > + return true; > +} > + > +static bool access_cntp_cval(struct kvm_vcpu *vcpu, > + const struct coproc_params *p, > + const struct coproc_reg *r) > +{ > + u64 val; > + > + if (p->is_write) { > + val =3D (u64)*vcpu_reg(vcpu, p->Rt2) << 32; > + val |=3D *vcpu_reg(vcpu, p->Rt1); > + kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL, val); > + } else { > + val =3D kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL); > + *vcpu_reg(vcpu, p->Rt1) =3D val; > + *vcpu_reg(vcpu, p->Rt2) =3D val >> 32; > + } > + > + return true; > +} > + > /* > * We could trap ID_DFR0 and tell the guest we don't support performance > * monitoring. Unfortunately the patch to make the kernel check ID_DFR0= was > @@ -423,10 +477,17 @@ static const struct coproc_reg cp15_regs[] =3D { > { CRn(13), CRm( 0), Op1( 0), Op2( 4), is32, > NULL, reset_unknown, c13_TID_PRIV }, > = > + /* CNTP */ > + { CRm64(14), Op1( 2), is64, access_cntp_cval}, > + > /* CNTKCTL: swapped by interrupt.S. */ > { CRn(14), CRm( 1), Op1( 0), Op2( 0), is32, > NULL, reset_val, c14_CNTKCTL, 0x00000000 }, > = > + /* CNTP */ > + { CRn(14), CRm( 2), Op1( 0), Op2( 0), is32, access_cntp_tval }, > + { CRn(14), CRm( 2), Op1( 0), Op2( 1), is32, access_cntp_ctl }, > + > /* The Configuration Base Address Register. */ > { CRn(15), CRm( 0), Op1( 4), Op2( 0), is32, access_cbar}, > }; > -- = > 2.7.4 > =