[PATCH v6 19/21] KVM: ARM: vgic: add the GICv3 backend
Marc Zyngier
marc.zyngier at arm.com
Mon Jun 30 08:01:48 PDT 2014
Introduce the support code for emulating a GICv2 on top of GICv3
hardware.
Acked-by: Catalin Marinas <catalin.marinas at arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
arch/arm64/include/asm/kvm_asm.h | 2 +
arch/arm64/kvm/vgic-v3-switch.S | 29 +++++
include/kvm/arm_vgic.h | 28 +++++
virt/kvm/arm/vgic-v3.c | 231 +++++++++++++++++++++++++++++++++++++++
4 files changed, 290 insertions(+)
create mode 100644 arch/arm64/kvm/vgic-v3-switch.S
create mode 100644 virt/kvm/arm/vgic-v3.c
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index 6252264..ed4987b 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -106,6 +106,8 @@ extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);
extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
+extern u64 __vgic_v3_get_ich_vtr_el2(void);
+
extern char __save_vgic_v2_state[];
extern char __restore_vgic_v2_state[];
diff --git a/arch/arm64/kvm/vgic-v3-switch.S b/arch/arm64/kvm/vgic-v3-switch.S
new file mode 100644
index 0000000..9fbf273
--- /dev/null
+++ b/arch/arm64/kvm/vgic-v3-switch.S
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2012,2013 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyngier at arm.com>
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/linkage.h>
+#include <linux/irqchip/arm-gic-v3.h>
+
+ .text
+ .pushsection .hyp.text, "ax"
+
+ENTRY(__vgic_v3_get_ich_vtr_el2)
+ mrs x0, ICH_VTR_EL2
+ ret
+ENDPROC(__vgic_v3_get_ich_vtr_el2)
+
+ .popsection
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 65f1121..35b0c12 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -33,6 +33,7 @@
#define VGIC_MAX_CPUS KVM_MAX_VCPUS
#define VGIC_V2_MAX_LRS (1 << 6)
+#define VGIC_V3_MAX_LRS 16
/* Sanity checks... */
#if (VGIC_MAX_CPUS > 8)
@@ -72,6 +73,7 @@ struct kvm_vcpu;
enum vgic_type {
VGIC_V2, /* Good ol' GICv2 */
+ VGIC_V3, /* New fancy GICv3 */
};
#define LR_STATE_PENDING (1 << 0)
@@ -172,6 +174,19 @@ struct vgic_v2_cpu_if {
u32 vgic_lr[VGIC_V2_MAX_LRS];
};
+struct vgic_v3_cpu_if {
+#ifdef CONFIG_ARM_GIC_V3
+ u32 vgic_hcr;
+ u32 vgic_vmcr;
+ u32 vgic_misr; /* Saved only */
+ u32 vgic_eisr; /* Saved only */
+ u32 vgic_elrsr; /* Saved only */
+ u32 vgic_ap0r[4];
+ u32 vgic_ap1r[4];
+ u64 vgic_lr[VGIC_V3_MAX_LRS];
+#endif
+};
+
struct vgic_cpu {
#ifdef CONFIG_KVM_ARM_VGIC
/* per IRQ to LR mapping */
@@ -190,6 +205,7 @@ struct vgic_cpu {
/* CPU vif control registers for world switch */
union {
struct vgic_v2_cpu_if vgic_v2;
+ struct vgic_v3_cpu_if vgic_v3;
};
#endif
};
@@ -224,6 +240,18 @@ bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run,
int vgic_v2_probe(struct device_node *vgic_node,
const struct vgic_ops **ops,
const struct vgic_params **params);
+#ifdef CONFIG_ARM_GIC_V3
+int vgic_v3_probe(struct device_node *vgic_node,
+ const struct vgic_ops **ops,
+ const struct vgic_params **params);
+#else
+static inline int vgic_v3_probe(struct device_node *vgic_node,
+ const struct vgic_ops **ops,
+ const struct vgic_params **params)
+{
+ return -ENODEV;
+}
+#endif
#else
static inline int kvm_vgic_hyp_init(void)
diff --git a/virt/kvm/arm/vgic-v3.c b/virt/kvm/arm/vgic-v3.c
new file mode 100644
index 0000000..f01d446
--- /dev/null
+++ b/virt/kvm/arm/vgic-v3.c
@@ -0,0 +1,231 @@
+/*
+ * Copyright (C) 2013 ARM Limited, All Rights Reserved.
+ * Author: Marc Zyngier <marc.zyngier at arm.com>
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/cpu.h>
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include <linux/irqchip/arm-gic-v3.h>
+
+#include <asm/kvm_emulate.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_mmu.h>
+
+/* These are for GICv2 emulation only */
+#define GICH_LR_VIRTUALID (0x3ffUL << 0)
+#define GICH_LR_PHYSID_CPUID_SHIFT (10)
+#define GICH_LR_PHYSID_CPUID (7UL << GICH_LR_PHYSID_CPUID_SHIFT)
+
+/*
+ * LRs are stored in reverse order in memory. make sure we index them
+ * correctly.
+ */
+#define LR_INDEX(lr) (VGIC_V3_MAX_LRS - 1 - lr)
+
+static u32 ich_vtr_el2;
+
+static struct vgic_lr vgic_v3_get_lr(const struct kvm_vcpu *vcpu, int lr)
+{
+ struct vgic_lr lr_desc;
+ u64 val = vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[LR_INDEX(lr)];
+
+ lr_desc.irq = val & GICH_LR_VIRTUALID;
+ if (lr_desc.irq <= 15)
+ lr_desc.source = (val >> GICH_LR_PHYSID_CPUID_SHIFT) & 0x7;
+ else
+ lr_desc.source = 0;
+ lr_desc.state = 0;
+
+ if (val & ICH_LR_PENDING_BIT)
+ lr_desc.state |= LR_STATE_PENDING;
+ if (val & ICH_LR_ACTIVE_BIT)
+ lr_desc.state |= LR_STATE_ACTIVE;
+ if (val & ICH_LR_EOI)
+ lr_desc.state |= LR_EOI_INT;
+
+ return lr_desc;
+}
+
+static void vgic_v3_set_lr(struct kvm_vcpu *vcpu, int lr,
+ struct vgic_lr lr_desc)
+{
+ u64 lr_val = (((u32)lr_desc.source << GICH_LR_PHYSID_CPUID_SHIFT) |
+ lr_desc.irq);
+
+ if (lr_desc.state & LR_STATE_PENDING)
+ lr_val |= ICH_LR_PENDING_BIT;
+ if (lr_desc.state & LR_STATE_ACTIVE)
+ lr_val |= ICH_LR_ACTIVE_BIT;
+ if (lr_desc.state & LR_EOI_INT)
+ lr_val |= ICH_LR_EOI;
+
+ vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[LR_INDEX(lr)] = lr_val;
+}
+
+static void vgic_v3_sync_lr_elrsr(struct kvm_vcpu *vcpu, int lr,
+ struct vgic_lr lr_desc)
+{
+ if (!(lr_desc.state & LR_STATE_MASK))
+ vcpu->arch.vgic_cpu.vgic_v3.vgic_elrsr |= (1U << lr);
+}
+
+static u64 vgic_v3_get_elrsr(const struct kvm_vcpu *vcpu)
+{
+ return vcpu->arch.vgic_cpu.vgic_v3.vgic_elrsr;
+}
+
+static u64 vgic_v3_get_eisr(const struct kvm_vcpu *vcpu)
+{
+ return vcpu->arch.vgic_cpu.vgic_v3.vgic_eisr;
+}
+
+static u32 vgic_v3_get_interrupt_status(const struct kvm_vcpu *vcpu)
+{
+ u32 misr = vcpu->arch.vgic_cpu.vgic_v3.vgic_misr;
+ u32 ret = 0;
+
+ if (misr & ICH_MISR_EOI)
+ ret |= INT_STATUS_EOI;
+ if (misr & ICH_MISR_U)
+ ret |= INT_STATUS_UNDERFLOW;
+
+ return ret;
+}
+
+static void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
+{
+ u32 vmcr = vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr;
+
+ vmcrp->ctlr = (vmcr & ICH_VMCR_CTLR_MASK) >> ICH_VMCR_CTLR_SHIFT;
+ vmcrp->abpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
+ vmcrp->bpr = (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
+ vmcrp->pmr = (vmcr & ICH_VMCR_PMR_MASK) >> ICH_VMCR_PMR_SHIFT;
+}
+
+static void vgic_v3_enable_underflow(struct kvm_vcpu *vcpu)
+{
+ vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr |= ICH_HCR_UIE;
+}
+
+static void vgic_v3_disable_underflow(struct kvm_vcpu *vcpu)
+{
+ vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr &= ~ICH_HCR_UIE;
+}
+
+static void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
+{
+ u32 vmcr;
+
+ vmcr = (vmcrp->ctlr << ICH_VMCR_CTLR_SHIFT) & ICH_VMCR_CTLR_MASK;
+ vmcr |= (vmcrp->abpr << ICH_VMCR_BPR1_SHIFT) & ICH_VMCR_BPR1_MASK;
+ vmcr |= (vmcrp->bpr << ICH_VMCR_BPR0_SHIFT) & ICH_VMCR_BPR0_MASK;
+ vmcr |= (vmcrp->pmr << ICH_VMCR_PMR_SHIFT) & ICH_VMCR_PMR_MASK;
+
+ vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr = vmcr;
+}
+
+static void vgic_v3_enable(struct kvm_vcpu *vcpu)
+{
+ /*
+ * By forcing VMCR to zero, the GIC will restore the binary
+ * points to their reset values. Anything else resets to zero
+ * anyway.
+ */
+ vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr = 0;
+
+ /* Get the show on the road... */
+ vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr = ICH_HCR_EN;
+}
+
+static const struct vgic_ops vgic_v3_ops = {
+ .get_lr = vgic_v3_get_lr,
+ .set_lr = vgic_v3_set_lr,
+ .sync_lr_elrsr = vgic_v3_sync_lr_elrsr,
+ .get_elrsr = vgic_v3_get_elrsr,
+ .get_eisr = vgic_v3_get_eisr,
+ .get_interrupt_status = vgic_v3_get_interrupt_status,
+ .enable_underflow = vgic_v3_enable_underflow,
+ .disable_underflow = vgic_v3_disable_underflow,
+ .get_vmcr = vgic_v3_get_vmcr,
+ .set_vmcr = vgic_v3_set_vmcr,
+ .enable = vgic_v3_enable,
+};
+
+static struct vgic_params vgic_v3_params;
+
+/**
+ * vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
+ * @node: pointer to the DT node
+ * @ops: address of a pointer to the GICv3 operations
+ * @params: address of a pointer to HW-specific parameters
+ *
+ * Returns 0 if a GICv3 has been found, with the low level operations
+ * in *ops and the HW parameters in *params. Returns an error code
+ * otherwise.
+ */
+int vgic_v3_probe(struct device_node *vgic_node,
+ const struct vgic_ops **ops,
+ const struct vgic_params **params)
+{
+ int ret = 0;
+ u32 gicv_idx;
+ struct resource vcpu_res;
+ struct vgic_params *vgic = &vgic_v3_params;
+
+ vgic->maint_irq = irq_of_parse_and_map(vgic_node, 0);
+ if (!vgic->maint_irq) {
+ kvm_err("error getting vgic maintenance irq from DT\n");
+ ret = -ENXIO;
+ goto out;
+ }
+
+ ich_vtr_el2 = kvm_call_hyp(__vgic_v3_get_ich_vtr_el2);
+
+ /*
+ * The ListRegs field is 5 bits, but there is a architectural
+ * maximum of 16 list registers. Just ignore bit 4...
+ */
+ vgic->nr_lr = (ich_vtr_el2 & 0xf) + 1;
+
+ if (of_property_read_u32(vgic_node, "#redistributor-regions", &gicv_idx))
+ gicv_idx = 1;
+
+ gicv_idx += 3; /* Also skip GICD, GICC, GICH */
+ if (of_address_to_resource(vgic_node, gicv_idx, &vcpu_res)) {
+ kvm_err("Cannot obtain GICV region\n");
+ ret = -ENXIO;
+ goto out;
+ }
+ vgic->vcpu_base = vcpu_res.start;
+ vgic->vctrl_base = NULL;
+ vgic->type = VGIC_V3;
+
+ kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
+ vcpu_res.start, vgic->maint_irq);
+
+ *ops = &vgic_v3_ops;
+ *params = vgic;
+
+out:
+ of_node_put(vgic_node);
+ return ret;
+}
--
2.0.0
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