From 0b04758b002bde9434053be2fff8064ac3d9d8bb Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:08 +0000 Subject: irqchip/gic-v3: Use SGIs without active state if offered To allow the direct injection of SGIs into a guest, the GICv4.1 architecture has to sacrifice the Active state so that SGIs look a lot like LPIs (they are injected by the same mechanism). In order not to break existing software, the architecture gives offers guests OSs the choice: SGIs with or without an active state. It is the hypervisors duty to honor the guest's choice. For this, the architecture offers a discovery bit indicating whether the GIC supports GICv4.1 SGIs (GICD_TYPER2.nASSGIcap), and another bit indicating whether the guest wants Active-less SGIs or not (controlled by GICD_CTLR.nASSGIreq). A hypervisor not supporting GICv4.1 SGIs would leave nASSGIcap clear, and a guest not knowing about GICv4.1 SGIs (or definitely wanting an Active state) would leave nASSGIreq clear (both being thankfully backward compatible with older revisions of the GIC). Since Linux is perfectly happy without an active state on SGIs, inform the hypervisor that we'll use that if offered. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Link: https://lore.kernel.org/r/20200304203330.4967-2-maz@kernel.org --- include/linux/irqchip/arm-gic-v3.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index 83439bfb6c5b..c29a02678a6f 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -57,6 +57,7 @@ #define GICD_SPENDSGIR 0x0F20 #define GICD_CTLR_RWP (1U << 31) +#define GICD_CTLR_nASSGIreq (1U << 8) #define GICD_CTLR_DS (1U << 6) #define GICD_CTLR_ARE_NS (1U << 4) #define GICD_CTLR_ENABLE_G1A (1U << 1) @@ -90,6 +91,7 @@ #define GICD_TYPER_ESPIS(typer) \ (((typer) & GICD_TYPER_ESPI) ? GICD_TYPER_SPIS((typer) >> 27) : 0) +#define GICD_TYPER2_nASSGIcap (1U << 8) #define GICD_TYPER2_VIL (1U << 7) #define GICD_TYPER2_VID GENMASK(4, 0) -- cgit v1.2.3 From f3a059219bc718ccc3bf3ff894f089b7e9a93139 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:10 +0000 Subject: irqchip/gic-v4.1: Ensure mutual exclusion between vPE affinity change and RD access Before GICv4.1, all operations would be serialized with the affinity changes by virtue of using the same ITS command queue. With v4.1, things change, as invalidations (and a number of other operations) are issued using the redistributor MMIO frame. We must thus make sure that these redistributor accesses cannot race against aginst the affinity change, or we may end-up talking to the wrong redistributor. To ensure this, we expand the irq_to_cpuid() helper to take a spinlock when the LPI is mapped to a vLPI (a new per-VPE lock) on each operation that requires mutual exclusion. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Link: https://lore.kernel.org/r/20200304203330.4967-4-maz@kernel.org --- include/linux/irqchip/arm-gic-v4.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include') diff --git a/include/linux/irqchip/arm-gic-v4.h b/include/linux/irqchip/arm-gic-v4.h index d9c34968467a..439963f4c66a 100644 --- a/include/linux/irqchip/arm-gic-v4.h +++ b/include/linux/irqchip/arm-gic-v4.h @@ -53,6 +53,11 @@ struct its_vpe { }; }; + /* + * Ensures mutual exclusion between affinity setting of the + * vPE and vLPI operations using vpe->col_idx. + */ + raw_spinlock_t vpe_lock; /* * This collection ID is used to indirect the target * redistributor for this VPE. The ID itself isn't involved in -- cgit v1.2.3 From 9058a4e980648e7d068a7f7726a8ea4c67d0e88a Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:12 +0000 Subject: irqchip/gic-v4.1: Ensure mutual exclusion betwen invalidations on the same RD The GICv4.1 spec says that it is CONTRAINED UNPREDICTABLE to write to any of the GICR_INV{LPI,ALL}R registers if GICR_SYNCR.Busy == 1. To deal with it, we must ensure that only a single invalidation can happen at a time for a given redistributor. Add a per-RD lock to that effect and take it around the invalidation/syncr-read to deal with this. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Reviewed-by: Eric Auger Link: https://lore.kernel.org/r/20200304203330.4967-6-maz@kernel.org --- include/linux/irqchip/arm-gic-v3.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index c29a02678a6f..b28acfa71f82 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -652,6 +652,7 @@ struct rdists { struct { + raw_spinlock_t rd_lock; void __iomem *rd_base; struct page *pend_page; phys_addr_t phys_base; -- cgit v1.2.3 From 3c40706d05fdea421e991da50e72a29d41131a66 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:13 +0000 Subject: irqchip/gic-v4.1: Advertise support v4.1 to KVM Tell KVM that we support v4.1. Nothing uses this information so far. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Reviewed-by: Eric Auger Link: https://lore.kernel.org/r/20200304203330.4967-7-maz@kernel.org --- include/linux/irqchip/arm-gic-common.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/irqchip/arm-gic-common.h b/include/linux/irqchip/arm-gic-common.h index b9850f5f1906..fa8c0455c352 100644 --- a/include/linux/irqchip/arm-gic-common.h +++ b/include/linux/irqchip/arm-gic-common.h @@ -32,6 +32,8 @@ struct gic_kvm_info { struct resource vctrl; /* vlpi support */ bool has_v4; + /* rvpeid support */ + bool has_v4_1; }; const struct gic_kvm_info *gic_get_kvm_info(void); -- cgit v1.2.3 From 166cba71818cd49d7d815fdc6f97c63395e94fc5 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:15 +0000 Subject: irqchip/gic-v4.1: Plumb skeletal VSGI irqchip Since GICv4.1 has the capability to inject 16 SGIs into each VPE, and that I'm keen not to invent too many specific interfaces to manipulate these interrupts, let's pretend that each of these SGIs is an actual Linux interrupt. For that matter, let's introduce a minimal irqchip and irqdomain setup that will get fleshed up in the following patches. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Reviewed-by: Eric Auger Link: https://lore.kernel.org/r/20200304203330.4967-9-maz@kernel.org --- include/linux/irqchip/arm-gic-v4.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/irqchip/arm-gic-v4.h b/include/linux/irqchip/arm-gic-v4.h index 439963f4c66a..44e8c19e3d56 100644 --- a/include/linux/irqchip/arm-gic-v4.h +++ b/include/linux/irqchip/arm-gic-v4.h @@ -49,6 +49,11 @@ struct its_vpe { }; /* GICv4.1 implementations */ struct { + struct { + u8 priority; + bool enabled; + bool group; + } sgi_config[16]; atomic_t vmapp_count; }; }; @@ -123,6 +128,8 @@ int its_unmap_vlpi(int irq); int its_prop_update_vlpi(int irq, u8 config, bool inv); struct irq_domain_ops; -int its_init_v4(struct irq_domain *domain, const struct irq_domain_ops *ops); +int its_init_v4(struct irq_domain *domain, + const struct irq_domain_ops *vpe_ops, + const struct irq_domain_ops *sgi_ops); #endif -- cgit v1.2.3 From e252cf8a34d92adf41124cb59b19b49d25395548 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:16 +0000 Subject: irqchip/gic-v4.1: Add initial SGI configuration The GICv4.1 ITS has yet another new command (VSGI) which allows a VPE-targeted SGI to be configured (or have its pending state cleared). Add support for this command and plumb it into the activate irqdomain callback so that it is ready to be used. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Link: https://lore.kernel.org/r/20200304203330.4967-10-maz@kernel.org --- include/linux/irqchip/arm-gic-v3.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index b28acfa71f82..fd3be49ac9a5 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -502,8 +502,9 @@ #define GITS_CMD_VMAPTI GITS_CMD_GICv4(GITS_CMD_MAPTI) #define GITS_CMD_VMOVI GITS_CMD_GICv4(GITS_CMD_MOVI) #define GITS_CMD_VSYNC GITS_CMD_GICv4(GITS_CMD_SYNC) -/* VMOVP and INVDB are the odd ones, as they dont have a physical counterpart */ +/* VMOVP, VSGI and INVDB are the odd ones, as they dont have a physical counterpart */ #define GITS_CMD_VMOVP GITS_CMD_GICv4(2) +#define GITS_CMD_VSGI GITS_CMD_GICv4(3) #define GITS_CMD_INVDB GITS_CMD_GICv4(0xe) /* -- cgit v1.2.3 From 7017ff0ee1de9d45fafee88a4e7890cce92f482e Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:18 +0000 Subject: irqchip/gic-v4.1: Plumb get/set_irqchip_state SGI callbacks To implement the get/set_irqchip_state callbacks (limited to the PENDING state), we have to use a particular set of hacks: - Reading the pending state is done by using a pair of new redistributor registers (GICR_VSGIR, GICR_VSGIPENDR), which allow the 16 interrupts state to be retrieved. - Setting the pending state is done by generating it as we'd otherwise do for a guest (writing to GITS_SGIR). - Clearing the pending state is done by emitting a VSGI command with the "clear" bit set. This requires some interesting locking though: - When talking to the redistributor, we must make sure that the VPE affinity doesn't change, hence taking the VPE lock. - At the same time, we must ensure that nobody accesses the same redistributor's GICR_VSGIR registers for a different VPE, which would corrupt the reading of the pending bits. We thus take the per-RD spinlock. Much fun. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Link: https://lore.kernel.org/r/20200304203330.4967-12-maz@kernel.org --- include/linux/irqchip/arm-gic-v3.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'include') diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index fd3be49ac9a5..590cdbeba9d5 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -345,6 +345,15 @@ #define GICR_VPENDBASER_4_1_VGRP1EN (1ULL << 58) #define GICR_VPENDBASER_4_1_VPEID GENMASK_ULL(15, 0) +#define GICR_VSGIR 0x0080 + +#define GICR_VSGIR_VPEID GENMASK(15, 0) + +#define GICR_VSGIPENDR 0x0088 + +#define GICR_VSGIPENDR_BUSY (1U << 31) +#define GICR_VSGIPENDR_PENDING GENMASK(15, 0) + /* * ITS registers, offsets from ITS_base */ @@ -368,6 +377,11 @@ #define GITS_TRANSLATER 0x10040 +#define GITS_SGIR 0x20020 + +#define GITS_SGIR_VPEID GENMASK_ULL(47, 32) +#define GITS_SGIR_VINTID GENMASK_ULL(3, 0) + #define GITS_CTLR_ENABLE (1U << 0) #define GITS_CTLR_ImDe (1U << 1) #define GITS_CTLR_ITS_NUMBER_SHIFT 4 -- cgit v1.2.3 From 05d32df13c6b3c0850b68928048536e9a736d520 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:19 +0000 Subject: irqchip/gic-v4.1: Plumb set_vcpu_affinity SGI callbacks Just like for vLPIs, there is some configuration information that cannot be directly communicated through the normal irqchip API, and we have to use our good old friend set_vcpu_affinity as a side-band communication mechanism. This is used to configure group and priority for a given vSGI. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Reviewed-by: Eric Auger Link: https://lore.kernel.org/r/20200304203330.4967-13-maz@kernel.org --- include/linux/irqchip/arm-gic-v4.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include') diff --git a/include/linux/irqchip/arm-gic-v4.h b/include/linux/irqchip/arm-gic-v4.h index 44e8c19e3d56..1b34100e3536 100644 --- a/include/linux/irqchip/arm-gic-v4.h +++ b/include/linux/irqchip/arm-gic-v4.h @@ -103,6 +103,7 @@ enum its_vcpu_info_cmd_type { SCHEDULE_VPE, DESCHEDULE_VPE, INVALL_VPE, + PROP_UPDATE_VSGI, }; struct its_cmd_info { @@ -115,6 +116,10 @@ struct its_cmd_info { bool g0en; bool g1en; }; + struct { + u8 priority; + bool group; + }; }; }; -- cgit v1.2.3 From ae699ad348cdcd416cbf28e8a02fc468780161f7 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:20 +0000 Subject: irqchip/gic-v4.1: Move doorbell management to the GICv4 abstraction layer In order to hide some of the differences between v4.0 and v4.1, move the doorbell management out of the KVM code, and into the GICv4-specific layer. This allows the calling code to ask for the doorbell when blocking, and otherwise to leave the doorbell permanently disabled. This matches the v4.1 code perfectly, and only results in a minor refactoring of the v4.0 code. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Link: https://lore.kernel.org/r/20200304203330.4967-14-maz@kernel.org --- include/kvm/arm_vgic.h | 1 + include/linux/irqchip/arm-gic-v4.h | 3 ++- 2 files changed, 3 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 9d53f545a3d5..63457908c9c4 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -70,6 +70,7 @@ struct vgic_global { /* Hardware has GICv4? */ bool has_gicv4; + bool has_gicv4_1; /* GIC system register CPU interface */ struct static_key_false gicv3_cpuif; diff --git a/include/linux/irqchip/arm-gic-v4.h b/include/linux/irqchip/arm-gic-v4.h index 1b34100e3536..34ed4b5754dd 100644 --- a/include/linux/irqchip/arm-gic-v4.h +++ b/include/linux/irqchip/arm-gic-v4.h @@ -125,7 +125,8 @@ struct its_cmd_info { int its_alloc_vcpu_irqs(struct its_vm *vm); void its_free_vcpu_irqs(struct its_vm *vm); -int its_schedule_vpe(struct its_vpe *vpe, bool on); +int its_make_vpe_resident(struct its_vpe *vpe, bool g0en, bool g1en); +int its_make_vpe_non_resident(struct its_vpe *vpe, bool db); int its_invall_vpe(struct its_vpe *vpe); int its_map_vlpi(int irq, struct its_vlpi_map *map); int its_get_vlpi(int irq, struct its_vlpi_map *map); -- cgit v1.2.3 From 6d31b6ff985dbd144b2c4d519cf573b8f81865d9 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:21 +0000 Subject: irqchip/gic-v4.1: Add VSGI allocation/teardown Allocate per-VPE SGIs when initializing the GIC-specific part of the VPE data structure. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Link: https://lore.kernel.org/r/20200304203330.4967-15-maz@kernel.org --- include/linux/irqchip/arm-gic-v4.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/irqchip/arm-gic-v4.h b/include/linux/irqchip/arm-gic-v4.h index 34ed4b5754dd..b120a01952fe 100644 --- a/include/linux/irqchip/arm-gic-v4.h +++ b/include/linux/irqchip/arm-gic-v4.h @@ -49,6 +49,8 @@ struct its_vpe { }; /* GICv4.1 implementations */ struct { + struct fwnode_handle *fwnode; + struct irq_domain *sgi_domain; struct { u8 priority; bool enabled; -- cgit v1.2.3 From d50676f5ce8481b98f9bbc1514b5d3f8747dd3c2 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:22 +0000 Subject: irqchip/gic-v4.1: Add VSGI property setup Add the SGI configuration entry point for KVM to use. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Link: https://lore.kernel.org/r/20200304203330.4967-16-maz@kernel.org --- include/linux/irqchip/arm-gic-v4.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/irqchip/arm-gic-v4.h b/include/linux/irqchip/arm-gic-v4.h index b120a01952fe..6976b8331b60 100644 --- a/include/linux/irqchip/arm-gic-v4.h +++ b/include/linux/irqchip/arm-gic-v4.h @@ -134,6 +134,7 @@ int its_map_vlpi(int irq, struct its_vlpi_map *map); int its_get_vlpi(int irq, struct its_vlpi_map *map); int its_unmap_vlpi(int irq); int its_prop_update_vlpi(int irq, u8 config, bool inv); +int its_prop_update_vsgi(int irq, u8 priority, bool group); struct irq_domain_ops; int its_init_v4(struct irq_domain *domain, -- cgit v1.2.3 From bacf2c60548befa8a31c2f19ef65bf2177fda33f Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 4 Mar 2020 20:33:26 +0000 Subject: KVM: arm64: GICv4.1: Allow SGIs to switch between HW and SW interrupts In order to let a guest buy in the new, active-less SGIs, we need to be able to switch between the two modes. Handle this by stopping all guest activity, transfer the state from one mode to the other, and resume the guest. Nothing calls this code so far, but a later patch will plug it into the MMIO emulation. Signed-off-by: Marc Zyngier Reviewed-by: Zenghui Yu Link: https://lore.kernel.org/r/20200304203330.4967-20-maz@kernel.org --- include/kvm/arm_vgic.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include') diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 63457908c9c4..69f4164d6477 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -231,6 +231,9 @@ struct vgic_dist { /* distributor enabled */ bool enabled; + /* Wants SGIs without active state */ + bool nassgireq; + struct vgic_irq *spis; struct vgic_io_device dist_iodev; -- cgit v1.2.3