Patchwork [RFC,v2,4/6] hw/kvm/arm_gic: Implement support for KVM in-kernel ARM GIC

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Submitter Peter Maydell
Date Oct. 10, 2012, 3:07 p.m.
Message ID <1349881659-8403-5-git-send-email-peter.maydell@linaro.org>
Download mbox | patch
Permalink /patch/190689/
State New
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Comments

Peter Maydell - Oct. 10, 2012, 3:07 p.m.
Implement support for using the KVM in-kernel GIC for ARM.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 hw/a15mpcore.c       |    8 ++-
 hw/arm/Makefile.objs |    1 +
 hw/kvm/arm_gic.c     |  162 ++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 170 insertions(+), 1 deletion(-)
 create mode 100644 hw/kvm/arm_gic.c
Andreas Färber - Oct. 10, 2012, 5:23 p.m.
Am 10.10.2012 17:07, schrieb Peter Maydell:
> Implement support for using the KVM in-kernel GIC for ARM.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>  hw/a15mpcore.c       |    8 ++-
>  hw/arm/Makefile.objs |    1 +
>  hw/kvm/arm_gic.c     |  162 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 170 insertions(+), 1 deletion(-)
>  create mode 100644 hw/kvm/arm_gic.c
> 
> diff --git a/hw/a15mpcore.c b/hw/a15mpcore.c
> index fc0a02a..a37fc61 100644
> --- a/hw/a15mpcore.c
> +++ b/hw/a15mpcore.c
> @@ -19,6 +19,7 @@
>   */
>  
>  #include "sysbus.h"
> +#include "kvm.h"
>  
>  /* A15MP private memory region.  */
>  
> @@ -41,7 +42,12 @@ static int a15mp_priv_init(SysBusDevice *dev)
>      A15MPPrivState *s = FROM_SYSBUS(A15MPPrivState, dev);
>      SysBusDevice *busdev;
>  
> -    s->gic = qdev_create(NULL, "arm_gic");
> +    if (kvm_irqchip_in_kernel()) {
> +        s->gic = qdev_create(NULL, "kvm-arm_gic");
> +    } else {
> +        s->gic = qdev_create(NULL, "arm_gic");
> +    }

You could follow x86 more closely by just selecting apic_type. (Then if
we drop/change qdev_create() at some point it's one change less.)

> +
>      qdev_prop_set_uint32(s->gic, "num-cpu", s->num_cpu);
>      qdev_prop_set_uint32(s->gic, "num-irq", s->num_irq);
>      qdev_prop_set_uint32(s->gic, "revision", 2);
[...]
> diff --git a/hw/kvm/arm_gic.c b/hw/kvm/arm_gic.c
> new file mode 100644
> index 0000000..3ec538d
> --- /dev/null
> +++ b/hw/kvm/arm_gic.c
> @@ -0,0 +1,162 @@
> +/*
> + * ARM Generic Interrupt Controller using KVM in-kernel support
> + *
> + * Copyright (c) 2012 Linaro Limited
> + * Written by Peter Maydell
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation, either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * 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 "hw/sysbus.h"
> +#include "kvm.h"
> +#include "hw/arm_gic_internal.h"
> +
> +#define TYPE_KVM_ARM_GIC "kvm-arm_gic"

"kvm-arm-gic"?

> +#define KVM_ARM_GIC(obj) \
> +     OBJECT_CHECK(gic_state, (obj), TYPE_KVM_ARM_GIC)
> +#define KVM_ARM_GIC_CLASS(klass) \
> +     OBJECT_CLASS_CHECK(KVMARMGICClass, (klass), TYPE_KVM_ARM_GIC)
> +#define KVM_ARM_GIC_GET_CLASS(obj) \
> +     OBJECT_GET_CLASS(KVMARMGICClass, (obj), TYPE_KVM_ARM_GIC)
> +
> +typedef struct KVMARMGICClass {
> +    ARMGICCommonClass parent_class;
> +    int (*parent_init)(SysBusDevice *dev);
> +    void (*parent_reset)(DeviceState *dev);
> +} KVMARMGICClass;
> +
> +static void kvm_arm_gic_set_irq(void *opaque, int irq, int level)
> +{
> +    /* Meaning of the 'irq' parameter:
> +     *  [0..N-1] : external interrupts
> +     *  [N..N+31] : PPI (internal) interrupts for CPU 0
> +     *  [N+32..N+63] : PPI (internal interrupts for CPU 1
> +     *  ...
> +     * Convert this to the kernel's desired encoding, which
> +     * has separate fields in the irq number for type,
> +     * CPU number and interrupt number.
> +     */
> +    gic_state *s = (gic_state *)opaque;

You don't happen to have time to clean up gic_state -> GICState before
spreading its use? ;)

[...]
> +static TypeInfo arm_gic_info = {

static const

> +    .name = TYPE_KVM_ARM_GIC,
> +    .parent = TYPE_ARM_GIC_COMMON,
> +    .instance_size = sizeof(gic_state),
> +    .class_init = kvm_arm_gic_class_init,
> +    .class_size = sizeof(KVMARMGICClass),
> +};
> +
> +static void arm_gic_register_types(void)

kvm_arm_gic_register_types?

> +{
> +    type_register_static(&arm_gic_info);
> +}
> +
> +type_init(arm_gic_register_types)
> 

Andreas
Peter Maydell - Oct. 10, 2012, 5:35 p.m.
On 10 October 2012 18:23, Andreas Färber <afaerber@suse.de> wrote:
> Am 10.10.2012 17:07, schrieb Peter Maydell:
>> Implement support for using the KVM in-kernel GIC for ARM.
>>
>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>> ---
>>  hw/a15mpcore.c       |    8 ++-
>>  hw/arm/Makefile.objs |    1 +
>>  hw/kvm/arm_gic.c     |  162 ++++++++++++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 170 insertions(+), 1 deletion(-)
>>  create mode 100644 hw/kvm/arm_gic.c
>>
>> diff --git a/hw/a15mpcore.c b/hw/a15mpcore.c
>> index fc0a02a..a37fc61 100644
>> --- a/hw/a15mpcore.c
>> +++ b/hw/a15mpcore.c
>> @@ -19,6 +19,7 @@
>>   */
>>
>>  #include "sysbus.h"
>> +#include "kvm.h"
>>
>>  /* A15MP private memory region.  */
>>
>> @@ -41,7 +42,12 @@ static int a15mp_priv_init(SysBusDevice *dev)
>>      A15MPPrivState *s = FROM_SYSBUS(A15MPPrivState, dev);
>>      SysBusDevice *busdev;
>>
>> -    s->gic = qdev_create(NULL, "arm_gic");
>> +    if (kvm_irqchip_in_kernel()) {
>> +        s->gic = qdev_create(NULL, "kvm-arm_gic");
>> +    } else {
>> +        s->gic = qdev_create(NULL, "arm_gic");
>> +    }
>
> You could follow x86 more closely by just selecting apic_type. (Then if
> we drop/change qdev_create() at some point it's one change less.)

Good idea.

>
>> +
>>      qdev_prop_set_uint32(s->gic, "num-cpu", s->num_cpu);
>>      qdev_prop_set_uint32(s->gic, "num-irq", s->num_irq);
>>      qdev_prop_set_uint32(s->gic, "revision", 2);
> [...]
>> diff --git a/hw/kvm/arm_gic.c b/hw/kvm/arm_gic.c
>> new file mode 100644
>> index 0000000..3ec538d
>> --- /dev/null
>> +++ b/hw/kvm/arm_gic.c
>> @@ -0,0 +1,162 @@
>> +/*
>> + * ARM Generic Interrupt Controller using KVM in-kernel support
>> + *
>> + * Copyright (c) 2012 Linaro Limited
>> + * Written by Peter Maydell
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation, either version 2 of the License, or
>> + * (at your option) any later version.
>> + *
>> + * 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 "hw/sysbus.h"
>> +#include "kvm.h"
>> +#include "hw/arm_gic_internal.h"
>> +
>> +#define TYPE_KVM_ARM_GIC "kvm-arm_gic"
>
> "kvm-arm-gic"?

I was trying to follow arm_gic but yes, I guess it's better
to go with the recommended style (which is all-hyphens, right?)

>> +#define KVM_ARM_GIC(obj) \
>> +     OBJECT_CHECK(gic_state, (obj), TYPE_KVM_ARM_GIC)
>> +#define KVM_ARM_GIC_CLASS(klass) \
>> +     OBJECT_CLASS_CHECK(KVMARMGICClass, (klass), TYPE_KVM_ARM_GIC)
>> +#define KVM_ARM_GIC_GET_CLASS(obj) \
>> +     OBJECT_GET_CLASS(KVMARMGICClass, (obj), TYPE_KVM_ARM_GIC)
>> +
>> +typedef struct KVMARMGICClass {
>> +    ARMGICCommonClass parent_class;
>> +    int (*parent_init)(SysBusDevice *dev);
>> +    void (*parent_reset)(DeviceState *dev);
>> +} KVMARMGICClass;
>> +
>> +static void kvm_arm_gic_set_irq(void *opaque, int irq, int level)
>> +{
>> +    /* Meaning of the 'irq' parameter:
>> +     *  [0..N-1] : external interrupts
>> +     *  [N..N+31] : PPI (internal) interrupts for CPU 0
>> +     *  [N+32..N+63] : PPI (internal interrupts for CPU 1
>> +     *  ...
>> +     * Convert this to the kernel's desired encoding, which
>> +     * has separate fields in the irq number for type,
>> +     * CPU number and interrupt number.
>> +     */
>> +    gic_state *s = (gic_state *)opaque;
>
> You don't happen to have time to clean up gic_state -> GICState before
> spreading its use? ;)

I can submit a patch if you like...

> [...]
>> +static TypeInfo arm_gic_info = {
>
> static const

Yep.

>> +    .name = TYPE_KVM_ARM_GIC,
>> +    .parent = TYPE_ARM_GIC_COMMON,
>> +    .instance_size = sizeof(gic_state),
>> +    .class_init = kvm_arm_gic_class_init,
>> +    .class_size = sizeof(KVMARMGICClass),
>> +};
>> +
>> +static void arm_gic_register_types(void)
>
> kvm_arm_gic_register_types?

Oops, yes, cut-n-pasto.

-- PMM

Patch

diff --git a/hw/a15mpcore.c b/hw/a15mpcore.c
index fc0a02a..a37fc61 100644
--- a/hw/a15mpcore.c
+++ b/hw/a15mpcore.c
@@ -19,6 +19,7 @@ 
  */
 
 #include "sysbus.h"
+#include "kvm.h"
 
 /* A15MP private memory region.  */
 
@@ -41,7 +42,12 @@  static int a15mp_priv_init(SysBusDevice *dev)
     A15MPPrivState *s = FROM_SYSBUS(A15MPPrivState, dev);
     SysBusDevice *busdev;
 
-    s->gic = qdev_create(NULL, "arm_gic");
+    if (kvm_irqchip_in_kernel()) {
+        s->gic = qdev_create(NULL, "kvm-arm_gic");
+    } else {
+        s->gic = qdev_create(NULL, "arm_gic");
+    }
+
     qdev_prop_set_uint32(s->gic, "num-cpu", s->num_cpu);
     qdev_prop_set_uint32(s->gic, "num-irq", s->num_irq);
     qdev_prop_set_uint32(s->gic, "revision", 2);
diff --git a/hw/arm/Makefile.objs b/hw/arm/Makefile.objs
index 6d049e7..38b10a8 100644
--- a/hw/arm/Makefile.objs
+++ b/hw/arm/Makefile.objs
@@ -31,5 +31,6 @@  obj-y += collie.o
 obj-y += imx_serial.o imx_ccm.o imx_timer.o imx_avic.o
 obj-y += kzm.o
 obj-$(CONFIG_FDT) += ../device_tree.o
+obj-$(CONFIG_KVM) += kvm/arm_gic.o
 
 obj-y := $(addprefix ../,$(obj-y))
diff --git a/hw/kvm/arm_gic.c b/hw/kvm/arm_gic.c
new file mode 100644
index 0000000..3ec538d
--- /dev/null
+++ b/hw/kvm/arm_gic.c
@@ -0,0 +1,162 @@ 
+/*
+ * ARM Generic Interrupt Controller using KVM in-kernel support
+ *
+ * Copyright (c) 2012 Linaro Limited
+ * Written by Peter Maydell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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 "hw/sysbus.h"
+#include "kvm.h"
+#include "hw/arm_gic_internal.h"
+
+#define TYPE_KVM_ARM_GIC "kvm-arm_gic"
+#define KVM_ARM_GIC(obj) \
+     OBJECT_CHECK(gic_state, (obj), TYPE_KVM_ARM_GIC)
+#define KVM_ARM_GIC_CLASS(klass) \
+     OBJECT_CLASS_CHECK(KVMARMGICClass, (klass), TYPE_KVM_ARM_GIC)
+#define KVM_ARM_GIC_GET_CLASS(obj) \
+     OBJECT_GET_CLASS(KVMARMGICClass, (obj), TYPE_KVM_ARM_GIC)
+
+typedef struct KVMARMGICClass {
+    ARMGICCommonClass parent_class;
+    int (*parent_init)(SysBusDevice *dev);
+    void (*parent_reset)(DeviceState *dev);
+} KVMARMGICClass;
+
+static void kvm_arm_gic_set_irq(void *opaque, int irq, int level)
+{
+    /* Meaning of the 'irq' parameter:
+     *  [0..N-1] : external interrupts
+     *  [N..N+31] : PPI (internal) interrupts for CPU 0
+     *  [N+32..N+63] : PPI (internal interrupts for CPU 1
+     *  ...
+     * Convert this to the kernel's desired encoding, which
+     * has separate fields in the irq number for type,
+     * CPU number and interrupt number.
+     */
+    gic_state *s = (gic_state *)opaque;
+    int kvm_irq, irqtype, cpu;
+
+    if (irq < (s->num_irq - GIC_INTERNAL)) {
+        /* External interrupt. The kernel numbers these like the GIC
+         * hardware, with external interrupt IDs starting after the
+         * internal ones.
+         */
+        irqtype = KVM_ARM_IRQ_TYPE_SPI;
+        cpu = 0;
+        irq += GIC_INTERNAL;
+    } else {
+        /* Internal interrupt: decode into (cpu, interrupt id) */
+        irqtype = KVM_ARM_IRQ_TYPE_PPI;
+        irq -= (s->num_irq - GIC_INTERNAL);
+        cpu = irq / GIC_INTERNAL;
+        irq %= GIC_INTERNAL;
+    }
+    kvm_irq = (irqtype << KVM_ARM_IRQ_TYPE_SHIFT)
+        | (cpu << KVM_ARM_IRQ_VCPU_SHIFT) | irq;
+
+    kvm_set_irq(kvm_state, kvm_irq, !!level);
+}
+
+static void kvm_arm_gic_put(gic_state *s)
+{
+    /* TODO: there isn't currently a kernel interface to set the GIC state */
+}
+
+static void kvm_arm_gic_get(gic_state *s)
+{
+    /* TODO: there isn't currently a kernel interface to get the GIC state */
+}
+
+static void kvm_arm_gic_reset(DeviceState *dev)
+{
+    gic_state *s = ARM_GIC_COMMON(dev);
+    KVMARMGICClass *kgc = KVM_ARM_GIC_GET_CLASS(s);
+    kgc->parent_reset(dev);
+    kvm_arm_gic_put(s);
+}
+
+static int kvm_arm_gic_init(SysBusDevice *dev)
+{
+    /* Device instance init function for the GIC sysbus device */
+    int i;
+    gic_state *s = FROM_SYSBUS(gic_state, dev);
+    KVMARMGICClass *kgc = KVM_ARM_GIC_GET_CLASS(s);
+
+    kgc->parent_init(dev);
+
+    i = s->num_irq - GIC_INTERNAL;
+    /* For the GIC, also expose incoming GPIO lines for PPIs for each CPU.
+     * GPIO array layout is thus:
+     *  [0..N-1] SPIs
+     *  [N..N+31] PPIs for CPU 0
+     *  [N+32..N+63] PPIs for CPU 1
+     *   ...
+     */
+    i += (GIC_INTERNAL * s->num_cpu);
+    qdev_init_gpio_in(&s->busdev.qdev, kvm_arm_gic_set_irq, i);
+    /* We never use our outbound IRQ lines but provide them so that
+     * we maintain the same interface as the non-KVM GIC.
+     */
+    for (i = 0; i < s->num_cpu; i++) {
+        sysbus_init_irq(&s->busdev, &s->parent_irq[i]);
+    }
+    /* Distributor */
+    memory_region_init_reservation(&s->iomem, "kvm-gic_dist", 0x1000);
+    sysbus_init_mmio(dev, &s->iomem);
+    /* CPU interface for current core. Unlike arm_gic, we don't
+     * provide the "interface for core #N" memory regions, because
+     * cores with a VGIC don't have those.
+     */
+    memory_region_init_reservation(&s->cpuiomem[0], "kvm-gic_cpu", 0x1000);
+    sysbus_init_mmio(dev, &s->cpuiomem[0]);
+    /* TODO: we should tell the kernel at some point the address
+     * of the private peripheral base. However we don't currently have
+     * any convenient infrastructure to do that, and in any case the
+     * kernel doesn't yet implement an ioctl to let us tell it.
+     */
+    return 0;
+}
+
+static void kvm_arm_gic_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(klass);
+    ARMGICCommonClass *agcc = ARM_GIC_COMMON_CLASS(klass);
+    KVMARMGICClass *kgc = KVM_ARM_GIC_CLASS(klass);
+    agcc->pre_save = kvm_arm_gic_get;
+    agcc->post_load = kvm_arm_gic_put;
+    kgc->parent_init = sbc->init;
+    kgc->parent_reset = dc->reset;
+    sbc->init = kvm_arm_gic_init;
+    dc->reset = kvm_arm_gic_reset;
+    dc->no_user = 1;
+}
+
+static TypeInfo arm_gic_info = {
+    .name = TYPE_KVM_ARM_GIC,
+    .parent = TYPE_ARM_GIC_COMMON,
+    .instance_size = sizeof(gic_state),
+    .class_init = kvm_arm_gic_class_init,
+    .class_size = sizeof(KVMARMGICClass),
+};
+
+static void arm_gic_register_types(void)
+{
+    type_register_static(&arm_gic_info);
+}
+
+type_init(arm_gic_register_types)