KVM: arm64: introduce ITS emulation file with stub functions

The ARM GICv3 ITS emulation code goes into a separate file, but
needs to be connected to the GICv3 emulation, of which it is an
option.
Introduce the skeleton with function stubs to be filled later.
Introduce the basic ITS data structure and initialize it, but don't
return any success yet, as we are not yet ready for the show.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Vadim Lomovtsev <Vadim.Lomovtsev@caviumnetworks.com>

diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile
index f90f4aa7f88d9d60ba4e8b53645c7d81d15f3e07..9803307899da2735e7e95f563c1dbbd58e71d3f8 100644 (file)
--- a/arch/arm64/kvm/Makefile
+++ b/arch/arm64/kvm/Makefile
@@ -25,5 +25,6 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic-v2-emul.o
 kvm-$(CONFIG_KVM_ARM_HOST) += vgic-v2-switch.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic-v3.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic-v3-emul.o
+kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/its-emul.o
 kvm-$(CONFIG_KVM_ARM_HOST) += vgic-v3-switch.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/arch_timer.o

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 8c6cb0eaabb8fa56a913d3d22ba0b5f3a4a002bd..9e9d4aa7355f7d1dc85bc2a9447f108f67f2f2f1 100644 (file)
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -156,6 +156,11 @@ struct vgic_io_device {
        struct kvm_io_device dev;
 };
 
+struct vgic_its {
+       bool                    enabled;
+       spinlock_t              lock;
+};
+
 struct vgic_dist {
        spinlock_t              lock;
        bool                    in_kernel;
@@ -264,6 +269,7 @@ struct vgic_dist {
        u64                     *pendbaser;
 
        bool                    lpis_enabled;
+       struct vgic_its         its;
 };
 
 struct vgic_v2_cpu_if {

diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
index 6949da7cf28a1c420a0beea0ca810f0fccb86344..24d156d45626e77fb29ff1500e1f827ac022786b 100644 (file)
--- a/include/linux/irqchip/arm-gic-v3.h
+++ b/include/linux/irqchip/arm-gic-v3.h
@@ -177,6 +177,7 @@
 #define GITS_CWRITER                   0x0088
 #define GITS_CREADR                    0x0090
 #define GITS_BASER                     0x0100
+#define GITS_IDREGS_BASE               0xffd0
 #define GITS_PIDR2                     GICR_PIDR2
 
 #define GITS_TRANSLATER                        0x10040

diff --git a/virt/kvm/arm/its-emul.c b/virt/kvm/arm/its-emul.c
new file mode 100644 (file)
index 0000000..659dd39
--- /dev/null
+++ b/virt/kvm/arm/its-emul.c
@@ -0,0 +1,125 @@
+/*
+ * GICv3 ITS emulation
+ *
+ * Copyright (C) 2015 ARM Ltd.
+ * Author: Andre Przywara <andre.przywara@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/irqchip/arm-gic-v3.h>
+#include <kvm/arm_vgic.h>
+
+#include <asm/kvm_emulate.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_mmu.h>
+
+#include "vgic.h"
+#include "its-emul.h"
+
+static bool handle_mmio_misc_gits(struct kvm_vcpu *vcpu,
+                                 struct kvm_exit_mmio *mmio,
+                                 phys_addr_t offset)
+{
+       return false;
+}
+
+static bool handle_mmio_gits_idregs(struct kvm_vcpu *vcpu,
+                                   struct kvm_exit_mmio *mmio,
+                                   phys_addr_t offset)
+{
+       return false;
+}
+
+static bool handle_mmio_gits_cbaser(struct kvm_vcpu *vcpu,
+                                   struct kvm_exit_mmio *mmio,
+                                   phys_addr_t offset)
+{
+       return false;
+}
+
+static bool handle_mmio_gits_cwriter(struct kvm_vcpu *vcpu,
+                                    struct kvm_exit_mmio *mmio,
+                                    phys_addr_t offset)
+{
+       return false;
+}
+
+static bool handle_mmio_gits_creadr(struct kvm_vcpu *vcpu,
+                                   struct kvm_exit_mmio *mmio,
+                                   phys_addr_t offset)
+{
+       return false;
+}
+
+static const struct vgic_io_range vgicv3_its_ranges[] = {
+       {
+               .base           = GITS_CTLR,
+               .len            = 0x10,
+               .bits_per_irq   = 0,
+               .handle_mmio    = handle_mmio_misc_gits,
+       },
+       {
+               .base           = GITS_CBASER,
+               .len            = 0x08,
+               .bits_per_irq   = 0,
+               .handle_mmio    = handle_mmio_gits_cbaser,
+       },
+       {
+               .base           = GITS_CWRITER,
+               .len            = 0x08,
+               .bits_per_irq   = 0,
+               .handle_mmio    = handle_mmio_gits_cwriter,
+       },
+       {
+               .base           = GITS_CREADR,
+               .len            = 0x08,
+               .bits_per_irq   = 0,
+               .handle_mmio    = handle_mmio_gits_creadr,
+       },
+       {
+               /* We don't need any memory from the guest. */
+               .base           = GITS_BASER,
+               .len            = 0x40,
+               .bits_per_irq   = 0,
+               .handle_mmio    = handle_mmio_raz_wi,
+       },
+       {
+               .base           = GITS_IDREGS_BASE,
+               .len            = 0x30,
+               .bits_per_irq   = 0,
+               .handle_mmio    = handle_mmio_gits_idregs,
+       },
+};
+
+/* This is called on setting the LPI enable bit in the redistributor. */
+void vgic_enable_lpis(struct kvm_vcpu *vcpu)
+{
+}
+
+int vits_init(struct kvm *kvm)
+{
+       struct vgic_dist *dist = &kvm->arch.vgic;
+       struct vgic_its *its = &dist->its;
+
+       spin_lock_init(&its->lock);
+
+       its->enabled = false;
+
+       return -ENXIO;
+}

diff --git a/virt/kvm/arm/its-emul.h b/virt/kvm/arm/its-emul.h
new file mode 100644 (file)
index 0000000..5dc8e2f
--- /dev/null
+++ b/virt/kvm/arm/its-emul.h
@@ -0,0 +1,35 @@
+/*
+ * GICv3 ITS emulation definitions
+ *
+ * Copyright (C) 2015 ARM Ltd.
+ * Author: Andre Przywara <andre.przywara@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/>.
+ */
+
+#ifndef __KVM_ITS_EMUL_H__
+#define __KVM_ITS_EMUL_H__
+
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+
+#include <asm/kvm_emulate.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_mmu.h>
+
+#include "vgic.h"
+
+void vgic_enable_lpis(struct kvm_vcpu *vcpu);
+int vits_init(struct kvm *kvm);
+
+#endif

diff --git a/virt/kvm/arm/vgic-v3-emul.c b/virt/kvm/arm/vgic-v3-emul.c
index 5269ad1275b8341a1de8ca72f6de227490ff1e74..f5865e7579c4aef6d348499040a83979dc9e0400 100644 (file)
--- a/virt/kvm/arm/vgic-v3-emul.c
+++ b/virt/kvm/arm/vgic-v3-emul.c
@@ -48,6 +48,7 @@
 #include <asm/kvm_mmu.h>
 
 #include "vgic.h"
+#include "its-emul.h"
 
 static bool handle_mmio_rao_wi(struct kvm_vcpu *vcpu,
                               struct kvm_exit_mmio *mmio, phys_addr_t offset)
@@ -530,9 +531,20 @@ static bool handle_mmio_ctlr_redist(struct kvm_vcpu *vcpu,
                                    struct kvm_exit_mmio *mmio,
                                    phys_addr_t offset)
 {
-       /* since we don't support LPIs, this register is zero for now */
-       vgic_reg_access(mmio, NULL, offset,
-                       ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED);
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+       u32 reg;
+
+       if (!vgic_has_its(vcpu->kvm)) {
+               vgic_reg_access(mmio, NULL, offset,
+                               ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED);
+               return false;
+       }
+       reg = dist->lpis_enabled ? GICR_CTLR_ENABLE_LPIS : 0;
+       vgic_reg_access(mmio, &reg, offset,
+                       ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
+       if (!dist->lpis_enabled && (reg & GICR_CTLR_ENABLE_LPIS)) {
+               /* Eventually do something */
+       }
        return false;
 }
 
@@ -861,6 +873,12 @@ static int vgic_v3_map_resources(struct kvm *kvm,
                rdbase += GIC_V3_REDIST_SIZE;
        }
 
+       if (vgic_has_its(kvm)) {
+               ret = vits_init(kvm);
+               if (ret)
+                       goto out_unregister;
+       }
+
        dist->redist_iodevs = iodevs;
        dist->ready = true;
        goto out;