KVM/ARM Architected Timers support

index c04c2a6..8a30186 100644
@@ -25,6 +25,7 @@
 #include <asm/arch_timer.h>
 #include <asm/system_info.h>
 #include <asm/sched_clock.h>
+#include <asm/virt.h>
 
 static unsigned long arch_timer_rate;
 

@@ -490,10 +491,14 @@ int __init arch_timer_of_register(void)
 		arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
 
 	/*
+	 * If HYP mode is available, we know that the physical timer
+	 * has been configured to be accessible from PL1. Use it, so
+	 * that a guest can use the virtual timer instead.
+	 *
 	 * If no interrupt provided for virtual timer, we'll have to
 	 * stick to the physical timer. It'd better be accessible...
 	 */
-	if (!arch_timer_ppi[VIRT_PPI]) {
+	if (is_hyp_mode_available() || !arch_timer_ppi[VIRT_PPI]) {
 		arch_timer_use_virtual = false;
 
 		if (!arch_timer_ppi[PHYS_SECURE_PPI] ||

new file mode 100644
index 0000000..513b852
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Marc Zyngier <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef __ASM_ARM_KVM_ARCH_TIMER_H
+#define __ASM_ARM_KVM_ARCH_TIMER_H
+
+struct arch_timer_kvm {
+};
+
+struct arch_timer_cpu {
+};
+
+#ifndef CONFIG_KVM_ARM_TIMER
+static inline int kvm_timer_hyp_init(void)
+{
+	return 0;
+};
+
+static inline int kvm_timer_init(struct kvm *kvm)
+{
+	return 0;
+}
+
+static inline void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) {}
+static inline void kvm_timer_sync_to_cpu(struct kvm_vcpu *vcpu) {}
+static inline void kvm_timer_sync_from_cpu(struct kvm_vcpu *vcpu) {}
+static inline void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu) {}
+#endif
+
+#endif

index d65faea..96cae84 100644
@@ -23,6 +23,7 @@
 #include <asm/kvm_asm.h>
 #include <asm/fpstate.h>
 #include <asm/kvm_vgic.h>
+#include <asm/kvm_arch_timer.h>
 
 #define KVM_MAX_VCPUS NR_CPUS
 #define KVM_MEMORY_SLOTS 32

@@ -56,6 +57,9 @@ struct kvm_arch {
 
 	/* Interrupt controller */
 	struct vgic_dist	vgic;
+
+	/* Timer */
+	struct arch_timer_kvm	timer;
 };
 
 #define KVM_NR_MEM_OBJS     40

@@ -93,6 +97,7 @@ struct kvm_vcpu_arch {
 
 	/* VGIC state */
 	struct vgic_cpu vgic_cpu;
+	struct arch_timer_cpu timer_cpu;
 
 	/*
 	 * Anything that is not used directly from assembly code goes

index 513b852..512ee39 100644
@@ -19,13 +19,63 @@
 #ifndef __ASM_ARM_KVM_ARCH_TIMER_H
 #define __ASM_ARM_KVM_ARCH_TIMER_H
 
+#include <linux/clocksource.h>
+#include <linux/hrtimer.h>
+#include <linux/workqueue.h>
+
 struct arch_timer_kvm {
+#ifdef CONFIG_KVM_ARM_TIMER
+	/* Is the timer enabled */
+	bool			enabled;
+
+	/*
+	 * Virtual offset (kernel access it through cntvoff, HYP code
+	 * access it as two 32bit values).
+	 */
+	union {
+		cycle_t		cntvoff;
+		struct {
+			u32	low; 	/* Restored only */
+			u32	high;  	/* Restored only */
+		} cntvoff32;
+	};
+#endif
 };
 
 struct arch_timer_cpu {
+#ifdef CONFIG_KVM_ARM_TIMER
+	/* Background timer used when the guest is not running */
+	struct hrtimer			timer;
+
+	/* Work queued with the above timer expires */
+	struct work_struct		expired;
+
+	/* Background timer active */
+	bool				armed;
+
+	/* Timer IRQ */
+	const struct kvm_irq_level	*irq;
+
+	/* Registers: control register, timer value */
+	u32				cntv_ctl;	/* Saved/restored */
+	union {
+		cycle_t			cntv_cval;
+		struct {
+			u32		low;		/* Saved/restored */
+			u32		high;		/* Saved/restored */
+		} cntv_cval32;
+	};
+#endif
 };
 
-#ifndef CONFIG_KVM_ARM_TIMER
+#ifdef CONFIG_KVM_ARM_TIMER
+int kvm_timer_hyp_init(void);
+int kvm_timer_init(struct kvm *kvm);
+void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu);
+void kvm_timer_sync_to_cpu(struct kvm_vcpu *vcpu);
+void kvm_timer_sync_from_cpu(struct kvm_vcpu *vcpu);
+void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu);
+#else
 static inline int kvm_timer_hyp_init(void)
 {
 	return 0;

index 290a13d..bb17def 100644
@@ -37,6 +37,12 @@ static struct kvm_regs a15_regs_reset = {
 	.cpsr = SVC_MODE | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT,
 };
 
+#ifdef CONFIG_KVM_ARM_TIMER
+static const struct kvm_irq_level a15_virt_timer_ppi = {
+	.irq	= 27,	/* A7/A15 specific */
+	.level	= 1,
+};
+#endif
 
 /*******************************************************************************
  * Exported reset function

@@ -59,6 +65,9 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
 			return -EINVAL;
 		cpu_reset = &a15_regs_reset;
 		vcpu->arch.midr = read_cpuid_id();
+#ifdef CONFIG_KVM_ARM_TIMER
+		vcpu->arch.timer_cpu.irq = &a15_virt_timer_ppi;
+#endif
 		break;
 	default:
 		return -ENODEV;

204 lines not on this page · raw message

index 1f4a894..1c4181e 100644
@@ -176,6 +176,14 @@ int main(void)
   DEFINE(VGIC_CPU_APR,		offsetof(struct vgic_cpu, vgic_apr));
   DEFINE(VGIC_CPU_LR,		offsetof(struct vgic_cpu, vgic_lr));
   DEFINE(VGIC_CPU_NR_LR,	offsetof(struct vgic_cpu, nr_lr));
+#ifdef CONFIG_KVM_ARM_TIMER
+  DEFINE(VCPU_TIMER_CNTV_CTL,	offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_ctl));
+  DEFINE(VCPU_TIMER_CNTV_CVALH,	offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_cval32.high));
+  DEFINE(VCPU_TIMER_CNTV_CVALL,	offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_cval32.low));
+  DEFINE(KVM_TIMER_CNTVOFF_H,	offsetof(struct kvm, arch.timer.cntvoff32.high));
+  DEFINE(KVM_TIMER_CNTVOFF_L,	offsetof(struct kvm, arch.timer.cntvoff32.low));
+  DEFINE(KVM_TIMER_ENABLED,	offsetof(struct kvm, arch.timer.enabled));
+#endif
   DEFINE(KVM_VGIC_VCTRL,	offsetof(struct kvm, arch.vgic.vctrl_base));
 #endif
   DEFINE(KVM_VTTBR,		offsetof(struct kvm, arch.vttbr));

index b03e604..c62bf28 100644
@@ -649,6 +649,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		update_vttbr(vcpu->kvm);
 
 		kvm_vgic_sync_to_cpu(vcpu);
+		kvm_timer_sync_to_cpu(vcpu);
 
 		local_irq_disable();
 

@@ -662,6 +663,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 
 		if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)) {
 			local_irq_enable();
+			kvm_timer_sync_from_cpu(vcpu);
 			kvm_vgic_sync_from_cpu(vcpu);
 			continue;
 		}

@@ -701,6 +703,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		 * Back from guest
 		 *************************************************************/
 
+		kvm_timer_sync_from_cpu(vcpu);
 		kvm_vgic_sync_from_cpu(vcpu);
 
 		ret = handle_exit(vcpu, run, ret);

index c62bf28..f8c377b 100644
@@ -283,6 +283,7 @@ out:
 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
 {
 	kvm_mmu_free_memory_caches(vcpu);
+	kvm_timer_vcpu_terminate(vcpu);
 	kmem_cache_free(kvm_vcpu_cache, vcpu);
 }
 

@@ -320,6 +321,9 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 	/* Set up VGIC */
 	kvm_vgic_vcpu_init(vcpu);
 
+	/* Set up the timer */
+	kvm_timer_vcpu_init(vcpu);
+
 	return 0;
 }
 

@@ -1010,6 +1014,13 @@ static int init_hyp_mode(void)
 	if (!err)
 		vgic_present = true;
 
+	/*
+	 * Init HYP architected timer support
+	 */
+	err = kvm_timer_hyp_init();
+	if (err)
+		goto out_free_mappings;
+
 	return 0;
 out_free_vfp:
 	free_percpu(kvm_host_vfp_state);

index 63fe0dd..494d94d 100644
@@ -1111,5 +1111,9 @@ int kvm_vgic_init(struct kvm *kvm)
 
 out:
 	mutex_unlock(&kvm->lock);
+
+	if (!ret)
+		kvm_timer_init(kvm);
+
 	return ret;
 }