[RFC PATCH 0/8] Support GICv3 ITS and vITS in 32-bit mode

[Vladimir Murzin]

Hi,

This series introduces GICv3 ITS and vITS to 32-bit world. The first
six patches make it possible to use ITS in a 32-bit guest with vITS on
64-bit host. The last two patches extend vITS to 32-bit host.

I used Andrea's its/v8 branch at [1] for testing with the following
diff on top

diff --git a/arm/aarch32/arm-cpu.c b/arm/aarch32/arm-cpu.c
index 27a8e17..16bba55 100644
--- a/arm/aarch32/arm-cpu.c
+++ b/arm/aarch32/arm-cpu.c
@@ -12,7 +12,7 @@ static void generate_fdt_nodes(void *fdt, struct kvm *kvm)
 {
 	int timer_interrupts[4] = {13, 14, 11, 10};
 
-	gic__generate_fdt_nodes(fdt, IRQCHIP_GICV2);
+	gic__generate_fdt_nodes(fdt, kvm->cfg.arch.irqchip);
 	timer__generate_fdt_nodes(fdt, kvm, timer_interrupts);
 }
 
diff --git a/arm/aarch32/include/kvm/kvm-arch.h b/arm/aarch32/include/kvm/kvm-arch.h
index 1632e3c..99231f6 100644
--- a/arm/aarch32/include/kvm/kvm-arch.h
+++ b/arm/aarch32/include/kvm/kvm-arch.h
@@ -1,8 +1,8 @@
 #ifndef KVM__KVM_ARCH_H
 #define KVM__KVM_ARCH_H
 
-#define ARM_GIC_DIST_SIZE	0x1000
-#define ARM_GIC_CPUI_SIZE	0x2000
+#define ARM_GIC_DIST_SIZE	0x100000
+#define ARM_GIC_CPUI_SIZE	0x200000
 
 #define ARM_KERN_OFFSET(...)	0x8000
 

After passing --irqchip=gicv3-its --force-pci to kvmtool I can see
that MSI is used:

# cat /proc/interrupts
           CPU0       
 18:       1251     GICv3  27 Level     arch_timer
 28:          0   ITS-MSI 49152 Edge      virtio3-config
 29:          0   ITS-MSI 49153 Edge      virtio3-input
 30:          0   ITS-MSI 49154 Edge      virtio3-output
 31:          0   ITS-MSI 32768 Edge      virtio2-config
 32:          2   ITS-MSI 32769 Edge      virtio2-input.0
 33:          1   ITS-MSI 32770 Edge      virtio2-output.0
 34:          0   ITS-MSI   0 Edge      virtio0-config
 35:        303   ITS-MSI   1 Edge      virtio0-requests
 36:          0   ITS-MSI 16384 Edge      virtio1-config
 37:        218   ITS-MSI 16385 Edge      virtio1-requests
IPI0:          0  CPU wakeup interrupts
IPI1:          0  Timer broadcast interrupts
IPI2:          0  Rescheduling interrupts
IPI3:          0  Function call interrupts
IPI4:          0  CPU stop interrupts
IPI5:          0  IRQ work interrupts
IPI6:          0  completion interrupts
Err:          0

Patches are aginst v4.9-rc1.

[1] git://www.linux-arm.org/kvmtool.git

Thanks!

Vladimir Murzin (8):
  irqchip/gic-v3-its: Change unsigned types for AArch32 compatibility
  irqchip/gic-v3-its: narrow down Entry Size when used as a divider
  irqchip/gicv3-its: specialise flush_dcache operation
  irqchip/gicv3-its: specialise readq and writeq accesses
  ARM: gic-v3-its: Add 32bit support to GICv3 ITS
  ARM: virt: select ARM_GIC_V3_ITS
  KVM: arm64: vgic-its: fix compatability with 32-bit
  ARM: KVM: Support vGICv3 ITS

 Documentation/virtual/kvm/api.txt   |    2 +-
 arch/arm/Kconfig                    |    1 +
 arch/arm/include/asm/arch_gicv3.h   |   59 ++++++++++++++++++++++---
 arch/arm/include/uapi/asm/kvm.h     |    2 +
 arch/arm/kvm/Kconfig                |    1 +
 arch/arm/kvm/Makefile               |    1 +
 arch/arm/kvm/arm.c                  |    6 +++
 arch/arm64/include/asm/arch_gicv3.h |   19 ++++++++
 arch/arm64/kvm/Kconfig              |    4 --
 arch/arm64/kvm/reset.c              |    6 ---
 drivers/irqchip/irq-gic-v3-its.c    |   81 +++++++++++++++++------------------
 include/linux/irqchip/arm-gic-v3.h  |   12 +++---
 virt/kvm/arm/vgic/vgic-its.c        |   11 ++---
 virt/kvm/arm/vgic/vgic-kvm-device.c |    2 -
 virt/kvm/arm/vgic/vgic-mmio-v3.c    |    2 -
 virt/kvm/arm/vgic/vgic.h            |   26 -----------
 16 files changed, 135 insertions(+), 100 deletions(-)

-- 
1.7.9.5