KVM/ARM Architected Timers support

index c8ef207..8adcd04 100644
@@ -26,6 +26,7 @@
 #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;
 

@@ -489,10 +490,14 @@ 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..68cb9e1
@@ -0,0 +1,85 @@
+/*
+ * 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
+
+#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 */
+	cycle_t			cntvoff;
+#endif
+};
+
+struct arch_timer_cpu {
+#ifdef CONFIG_KVM_ARM_TIMER
+	/* Registers: control register, timer value */
+	u32				cntv_ctl;	/* Saved/restored */
+	cycle_t				cntv_cval;	/* Saved/restored */
+
+	/*
+	 * Anything that is not used directly from assembly code goes
+	 * here.
+	 */
+
+	/* 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;
+#endif
+};
+
+#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_flush_hwstate(struct kvm_vcpu *vcpu);
+void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu);
+void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu);
+#else
+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_flush_hwstate(struct kvm_vcpu *vcpu) {}
+static inline void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu) {}
+static inline void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu) {}
+#endif
+
+#endif

index feac7f4..e58fd93 100644
@@ -23,6 +23,7 @@
 #include <asm/kvm_asm.h>
 #include <asm/kvm_mmio.h>
 #include <asm/fpstate.h>
+#include <asm/kvm_arch_timer.h>
 
 #define KVM_MAX_VCPUS CONFIG_KVM_ARM_MAX_VCPUS
 #define KVM_MEMORY_SLOTS 32

@@ -49,6 +50,9 @@ struct kvm_arch {
 	/* VTTBR value associated with below pgd and vmid */
 	u64    vttbr;
 
+	/* Timer */
+	struct arch_timer_kvm	timer;
+
 	/*
 	 * Anything that is not used directly from assembly code goes
 	 * here.

@@ -99,6 +103,7 @@ 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

271 lines not on this page · raw message

index 58d787b..8a60ed8 100644
@@ -45,7 +45,8 @@
 #define c13_TID_URW	23	/* Thread ID, User R/W */
 #define c13_TID_URO	24	/* Thread ID, User R/O */
 #define c13_TID_PRIV	25	/* Thread ID, Privileged */
-#define NR_CP15_REGS	26	/* Number of regs (incl. invalid) */
+#define c14_CNTKCTL	26	/* Timer Control Register (PL1) */
+#define NR_CP15_REGS	27	/* Number of regs (incl. invalid) */
 
 #define ARM_EXCEPTION_RESET	  0
 #define ARM_EXCEPTION_UNDEFINED   1

index 17cea2e..5ce738b 100644
@@ -179,6 +179,12 @@ 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_CVAL,	offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_cval));
+  DEFINE(KVM_TIMER_CNTVOFF,	offsetof(struct kvm, arch.timer.cntvoff));
+  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 68cb2b550..1a98b5c 100644
@@ -707,6 +707,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		update_vttbr(vcpu->kvm);
 
 		kvm_vgic_flush_hwstate(vcpu);
+		kvm_timer_flush_hwstate(vcpu);
 
 		local_irq_disable();
 

@@ -720,6 +721,7 @@ 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_hwstate(vcpu);
 			kvm_vgic_sync_hwstate(vcpu);
 			continue;
 		}

@@ -759,6 +761,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		 * Back from guest
 		 *************************************************************/
 
+		kvm_timer_sync_hwstate(vcpu);
 		kvm_vgic_sync_hwstate(vcpu);
 
 		ret = handle_exit(vcpu, run, ret);

index d782638..4ea9a98 100644
@@ -222,6 +222,10 @@ static const struct coproc_reg cp15_regs[] = {
 			NULL, reset_unknown, c13_TID_URO },
 	{ CRn(13), CRm( 0), Op1( 0), Op2( 4), is32,
 			NULL, reset_unknown, c13_TID_PRIV },
+
+	/* CNTKCTL: swapped by interrupt.S. */
+	{ CRn(14), CRm( 1), Op1( 0), Op2( 0), is32,
+			NULL, reset_val, c14_CNTKCTL, 0x00000000 },
 };
 
 /* Target specific emulation tables */

index 1a98b5c..2ab3552 100644
@@ -289,6 +289,7 @@ int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
 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);
 }
 

@@ -330,6 +331,9 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 	if (ret)
 		return ret;
 
+	/* Set up the timer */
+	kvm_timer_vcpu_init(vcpu);
+
 	return 0;
 }
 

@@ -1096,6 +1100,13 @@ static int init_hyp_mode(void)
 		vgic_present = true;
 #endif
 
+	/*
+	 * Init HYP architected timer support
+	 */
+	err = kvm_timer_hyp_init();
+	if (err)
+		goto out_free_mappings;
+
 	kvm_info("Hyp mode initialized successfully\n");
 	return 0;
 out_free_vfp:

index 519cde1..c451bf0 100644
@@ -1417,6 +1417,7 @@ int kvm_vgic_init(struct kvm *kvm)
 	for (i = VGIC_NR_PRIVATE_IRQS; i < VGIC_NR_IRQS; i += 4)
 		vgic_set_target_reg(kvm, 0, i);
 
+	kvm_timer_init(kvm);
 	kvm->arch.vgic.ready = true;
 out:
 	mutex_unlock(&kvm->lock);