virt: Add PCI host controller

[abrodkin]

This adds PCI bridge support to ARC's virt platform, which in its turn allows to both connect complex Virtio devices like VirtGPU, VirtRNG as well as pass-through host PCI devices including USB.

Note this requires corresponding support in the Linux kernel like this:

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index ba00c4e1e1c2..09efd393a0b2 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -48,6 +48,7 @@ config ARC select PCI_SYSCALL if PCI select PERF_USE_VMALLOC if ARC_CACHE_VIPT_ALIASING select HAVE_ARCH_JUMP_LABEL if ISA_ARCV2 && !CPU_ENDIAN_BE32 + select HAVE_PCI config ARCH_HAS_CACHE_LINE_SIZE def_bool y diff --git a/arch/arc/boot/dts/haps_hs.dts b/arch/arc/boot/dts/haps_hs.dts index 60d578e2781f..c57c7381c468 100644 --- a/arch/arc/boot/dts/haps_hs.dts +++ b/arch/arc/boot/dts/haps_hs.dts @@ -95,5 +95,45 @@ virtio4: virtio@f0108000 { reg = <0xf0108000 0x2000>; interrupts = <35>; }; + + pci { + compatible = "pci-host-ecam-generic"; + device_type = "pci"; + #address-cells = <3>; + #size-cells = <2>; + #interrupt-cells = <0x1>; + + bus-range = <0x0 0x0>; + reg = <0xe0000000 0x1000000>; + + // BUS_ADDRESS(3) CPU_PHYSICAL(1) SIZE(2) + ranges = <0x01000000 0x0 0x00000000 0xc0000000 0x0 0x00010000>, /* PIO */ + <0x02000000 0x0 0xd0000000 0xd0000000 0x0 0x10000000>; /* MMIO */ + + // PCI_DEVICE(3) INT#(1) CONTROLLER(PHANDLE) CONTROLLER_IRQ(1) + interrupt-map = < + 0x0000 0x0 0x0 0x1 &core_intc 40 /* 1st slot */ + 0x0000 0x0 0x0 0x2 &core_intc 41 + 0x0000 0x0 0x0 0x3 &core_intc 42 + 0x0000 0x0 0x0 0x4 &core_intc 43 + + 0x0800 0x0 0x0 0x1 &core_intc 41 /* 2nd slot */ + 0x0800 0x0 0x0 0x2 &core_intc 42 + 0x0800 0x0 0x0 0x3 &core_intc 43 + 0x0800 0x0 0x0 0x4 &core_intc 40 + + 0x1000 0x0 0x0 0x1 &core_intc 42 /* 3rd slot */ + 0x1000 0x0 0x0 0x2 &core_intc 43 + 0x1000 0x0 0x0 0x3 &core_intc 40 + 0x1000 0x0 0x0 0x4 &core_intc 41 + + 0x1800 0x0 0x0 0x1 &core_intc 43 /* 4th slot */ + 0x1800 0x0 0x0 0x2 &core_intc 40 + 0x1800 0x0 0x0 0x3 &core_intc 41 + 0x1800 0x0 0x0 0x4 &core_intc 42 + >; + + interrupt-map-mask = <0x1800 0x0 0x0 0x7>; + }; }; }; diff --git a/arch/arc/configs/haps_hs_defconfig b/arch/arc/configs/haps_hs_defconfig index 86cc5aa4537c..25b0bcd34782 100644 --- a/arch/arc/configs/haps_hs_defconfig +++ b/arch/arc/configs/haps_hs_defconfig @@ -31,6 +31,8 @@ CONFIG_NET_KEY=y CONFIG_INET=y # CONFIG_IPV6 is not set # CONFIG_WIRELESS is not set +CONFIG_PCI=y +CONFIG_PCI_HOST_GENERIC=y CONFIG_DEVTMPFS=y CONFIG_DEVTMPFS_MOUNT=y # CONFIG_STANDALONE is not set @@ -51,10 +53,16 @@ CONFIG_SERIAL_8250_NR_UARTS=1 CONFIG_SERIAL_8250_RUNTIME_UARTS=1 CONFIG_SERIAL_8250_DW=y CONFIG_SERIAL_OF_PLATFORM=y -# CONFIG_HW_RANDOM is not set +CONFIG_HW_RANDOM=y +CONFIG_HW_RANDOM_VIRTIO=y # CONFIG_HWMON is not set -# CONFIG_HID is not set -# CONFIG_USB_SUPPORT is not set +CONFIG_DRM=y +CONFIG_DRM_VIRTIO_GPU=y +CONFIG_USB=y +CONFIG_USB_XHCI_HCD=y +CONFIG_USB_EHCI_HCD=y +CONFIG_USB_OHCI_HCD=y +CONFIG_VIRTIO_PCI=y CONFIG_VIRTIO_MMIO=y # CONFIG_IOMMU_SUPPORT is not set CONFIG_EXT2_FS=y

./build/qemu-system-arc -M virt -monitor none -serial mon:stdio -kernel vmlinux -cpu archs \ -append "root=/dev/vda ro" -drive file=rootfs.ext2,format=raw,id=hd0 -device virtio-blk-device,drive=hd0 \ -netdev user,id=eth0 -device virtio-net-pci,netdev=eth0 -device virtio-rng-pci -device usb-ehci,id=ehci \ --global cpu.freq_hz=50000000 -device virtio-gpu-pci,id=video0 -display gtk,gl=on \ -device usb-host,vendorid=0x8564,productid=0x1000 

And that's what we get:

1. Host's random number generator in the guest for faster entropy generation.
2. Real USB flash-drive attached to host passed-through to the guest
3. 3D rendering off-loaded to the host and so working even faster than on the original HSDK, see 100+ FPS

[abrodkin]

@vineetgarc indeed with that fresh QEMU base the only change which is needed for the kernel is pure PCI-related stuff pasted as a diff for 5.10.y above. Should I send it as a formal patch for v5.11?

[vineetgarc]

You are adding more stuff in the minimal defconfig - all of this builds more code, loads slower in nSIM and haps

[cupertinomiranda]

I tried the code and at least we can get the random number generator maping working, which speeds up SSH significantly.
If no one has any objections, I will merge the pull request in our meeting tonight.

[cupertinomiranda]

All seems good, this is tested and works !