From: Marc Zyngier <marc.zyngier@arm.com>
To: Eric Auger <eric.auger@linaro.org>,
"eric.auger@st.com" <eric.auger@st.com>,
"christoffer.dall@linaro.org" <christoffer.dall@linaro.org>,
Andre Przywara <Andre.Przywara@arm.com>,
"p.fedin@samsung.com" <p.fedin@samsung.com>,
"kvmarm@lists.cs.columbia.edu" <kvmarm@lists.cs.columbia.edu>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>
Cc: "patches@linaro.org" <patches@linaro.org>
Subject: Re: [RFC 4/6] KVM: arm/arm64: enable irqchip routing
Date: Thu, 18 Jun 2015 18:53:38 +0100 [thread overview]
Message-ID: <558305A2.8020206@arm.com> (raw)
In-Reply-To: <1434649258-27065-5-git-send-email-eric.auger@linaro.org>
Hi Eric,
On 18/06/15 18:40, Eric Auger wrote:
> This patch adds compilation and link against irqchip.
>
> On ARM, irqchip routing is not really useful since there is
> a single irqchip. However main motivation behind using irqchip
> code is to enable MSI routing code. With the support of in-kernel
> GICv3 ITS emulation, it now seems to be a MUST HAVE requirement.
>
> Functions previously implemented in vgic.c and substitute
> to more complex irqchip implementation are removed:
>
> - kvm_send_userspace_msi
> - kvm_irq_map_chip_pin
> - kvm_set_irq
> - kvm_irq_map_gsi.
>
> They implemented a kernel default identity GSI routing. This is now
> replaced by user-side provided routing.
>
> Routing standard hooks are now implemented in vgic:
> - kvm_set_routing_entry
> - kvm_set_irq
> - kvm_set_msi
>
> Both HAVE_KVM_IRQCHIP and HAVE_KVM_IRQ_ROUTING are defined.
> KVM_CAP_IRQ_ROUTING is advertised and KVM_SET_GSI_ROUTING is allowed.
>
> MSI routing is not yet allowed.
>
> Signed-off-by: Eric Auger <eric.auger@linaro.org>
> ---
> Documentation/virtual/kvm/api.txt | 11 ++++--
> arch/arm/include/asm/kvm_host.h | 2 +
> arch/arm/kvm/Kconfig | 2 +
> arch/arm/kvm/Makefile | 2 +-
> arch/arm64/include/asm/kvm_host.h | 1 +
> arch/arm64/kvm/Kconfig | 2 +
> arch/arm64/kvm/Makefile | 2 +-
> include/kvm/arm_vgic.h | 9 -----
> virt/kvm/arm/vgic.c | 78 ++++++++++++++++++++++++---------------
> virt/kvm/irqchip.c | 2 +
> 10 files changed, 67 insertions(+), 44 deletions(-)
>
> diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
> index bcec91e..2bc96e1 100644
> --- a/Documentation/virtual/kvm/api.txt
> +++ b/Documentation/virtual/kvm/api.txt
> @@ -1395,7 +1395,7 @@ KVM_ASSIGN_DEV_IRQ. Partial deassignment of host or guest IRQ is allowed.
> 4.52 KVM_SET_GSI_ROUTING
>
> Capability: KVM_CAP_IRQ_ROUTING
> -Architectures: x86 s390
> +Architectures: x86 s390 arm arm64
> Type: vm ioctl
> Parameters: struct kvm_irq_routing (in)
> Returns: 0 on success, -1 on error
> @@ -2310,9 +2310,12 @@ Note that closing the resamplefd is not sufficient to disable the
> irqfd. The KVM_IRQFD_FLAG_RESAMPLE is only necessary on assignment
> and need not be specified with KVM_IRQFD_FLAG_DEASSIGN.
>
> -On ARM/ARM64, the gsi field in the kvm_irqfd struct specifies the Shared
> -Peripheral Interrupt (SPI) index, such that the GIC interrupt ID is
> -given by gsi + 32.
> +On ARM/ARM64, when GSI routing is not used, the gsi field in the
> +kvm_irqfd struct specifies the Shared Peripheral Interrupt (SPI) index,
> +such that the GIC interrupt ID is given by gsi + 32. When GSI routing is
> +setup:
> +- if irqchip routing: irqchip.pin + 32 is the SPI ID that is injected
> +- if MSI routing: the MSI data is used as interrupt ID (SPI or LPI).
This feels just wrong. With GICv3, the MSI data is not the LPI at all.
It is an opaque value that gets translated into an LPI when combined
with the DeviceID.
Thanks,
M.
--
Jazz is not dead. It just smells funny...
next prev parent reply other threads:[~2015-06-18 17:43 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-18 17:40 [RFC 0/6] KVM: arm/arm64: gsi routing support Eric Auger
2015-06-18 17:40 ` [RFC 1/6] KVM: api: add kvm_irq_routing_extended_msi Eric Auger
2015-06-22 16:32 ` Andre Przywara
2015-06-23 7:36 ` Eric Auger
2015-06-18 17:40 ` [RFC 2/6] KVM: kvm_host: add kvm_extended_msi Eric Auger
2015-06-18 17:40 ` [RFC 3/6] KVM: irqchip: convey devid to kvm_set_msi Eric Auger
2015-06-18 17:40 ` [RFC 4/6] KVM: arm/arm64: enable irqchip routing Eric Auger
2015-06-18 17:53 ` Marc Zyngier [this message]
2015-06-18 18:00 ` Eric Auger
2015-06-18 18:07 ` Marc Zyngier
2015-06-18 17:40 ` [RFC 5/6] KVM: arm/arm64: enable MSI routing Eric Auger
2015-06-18 17:40 ` [RFC 6/6] KVM: arm: implement kvm_set_msi by gsi direct mapping Eric Auger
2015-06-19 6:37 ` [RFC 0/6] KVM: arm/arm64: gsi routing support Pavel Fedin
2015-06-22 8:31 ` Eric Auger
2015-06-22 8:40 ` Andre Przywara
2015-06-22 9:21 ` Eric Auger
2015-06-23 7:38 ` Pavel Fedin
2015-06-23 7:50 ` Eric Auger
2015-06-23 8:50 ` Pavel Fedin
2015-06-23 9:44 ` Eric Auger
2015-06-23 9:03 ` Andre Przywara
2015-06-23 9:33 ` Eric Auger
2015-06-23 12:53 ` Eric Auger
2015-06-24 12:20 ` Pavel Fedin
2015-06-24 13:03 ` Eric Auger
2015-06-25 8:46 ` Pavel Fedin
2015-06-26 16:17 ` Eric Auger
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