1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) 2%YAML 1.2 3--- 4$id: http://devicetree.org/schemas/pci/host-generic-pci.yaml# 5$schema: http://devicetree.org/meta-schemas/core.yaml# 6 7title: Generic PCI host controller 8 9maintainers: 10 - Will Deacon <will@kernel.org> 11 12description: | 13 Firmware-initialised PCI host controllers and PCI emulations, such as the 14 virtio-pci implementations found in kvmtool and other para-virtualised 15 systems, do not require driver support for complexities such as regulator 16 and clock management. In fact, the controller may not even require the 17 configuration of a control interface by the operating system, instead 18 presenting a set of fixed windows describing a subset of IO, Memory and 19 Configuration Spaces. 20 21 Configuration Space is assumed to be memory-mapped (as opposed to being 22 accessed via an ioport) and laid out with a direct correspondence to the 23 geography of a PCI bus address by concatenating the various components to 24 form an offset. 25 26 For CAM, this 24-bit offset is: 27 28 cfg_offset(bus, device, function, register) = 29 bus << 16 | device << 11 | function << 8 | register 30 31 While ECAM extends this by 4 bits to accommodate 4k of function space: 32 33 cfg_offset(bus, device, function, register) = 34 bus << 20 | device << 15 | function << 12 | register 35 36properties: 37 compatible: 38 description: Depends on the layout of configuration space (CAM vs ECAM 39 respectively). May also have more specific compatibles. 40 oneOf: 41 - description: 42 PCIe host controller in Arm Juno based on PLDA XpressRICH3-AXI IP 43 items: 44 - const: arm,juno-r1-pcie 45 - const: plda,xpressrich3-axi 46 - const: pci-host-ecam-generic 47 - description: | 48 ThunderX PCI host controller for pass-1.x silicon 49 50 Firmware-initialized PCI host controller to on-chip devices found on 51 some Cavium ThunderX processors. These devices have ECAM-based config 52 access, but the BARs are all at fixed addresses. We handle the fixed 53 addresses by synthesizing Enhanced Allocation (EA) capabilities for 54 these devices. 55 const: cavium,pci-host-thunder-ecam 56 - description: 57 Cavium ThunderX PEM firmware-initialized PCIe host controller 58 const: cavium,pci-host-thunder-pem 59 - description: 60 HiSilicon Hip06/Hip07 PCIe host bridge in almost-ECAM mode. Some 61 firmware places the host controller in a mode where it is ECAM 62 compliant for all devices other than the root complex. 63 enum: 64 - hisilicon,hip06-pcie-ecam 65 - hisilicon,hip07-pcie-ecam 66 - description: | 67 In some cases, firmware may already have configured the Synopsys 68 DesignWare PCIe controller in RC mode with static ATU window mappings 69 that cover all config, MMIO and I/O spaces in a [mostly] ECAM 70 compatible fashion. In this case, there is no need for the OS to 71 perform any low level setup of clocks, PHYs or device registers, nor 72 is there any reason for the driver to reconfigure ATU windows for 73 config and/or IO space accesses at runtime. 74 75 In cases where the IP was synthesized with a minimum ATU window size 76 of 64 KB, it cannot be supported by the generic ECAM driver, because 77 it requires special config space accessors that filter accesses to 78 device #1 and beyond on the first bus. 79 items: 80 - enum: 81 - marvell,armada8k-pcie-ecam 82 - socionext,synquacer-pcie-ecam 83 - const: snps,dw-pcie-ecam 84 - description: 85 CAM or ECAM compliant PCI host controllers without any quirks 86 enum: 87 - pci-host-cam-generic 88 - pci-host-ecam-generic 89 90 reg: 91 description: 92 The Configuration Space base address and size, as accessed from the parent 93 bus. The base address corresponds to the first bus in the "bus-range" 94 property. If no "bus-range" is specified, this will be bus 0 (the 95 default). Some host controllers have a 2nd non-compliant address range, 96 so 2 entries are allowed. 97 minItems: 1 98 maxItems: 2 99 100 ranges: 101 description: 102 As described in IEEE Std 1275-1994, but must provide at least a 103 definition of non-prefetchable memory. One or both of prefetchable Memory 104 and IO Space may also be provided. 105 minItems: 1 106 maxItems: 3 107 108 dma-coherent: true 109 110required: 111 - compatible 112 - reg 113 - ranges 114 115allOf: 116 - $ref: /schemas/pci/pci-bus.yaml# 117 - if: 118 properties: 119 compatible: 120 contains: 121 const: arm,juno-r1-pcie 122 then: 123 required: 124 - dma-coherent 125 126 - if: 127 properties: 128 compatible: 129 not: 130 contains: 131 enum: 132 - cavium,pci-host-thunder-pem 133 - hisilicon,hip06-pcie-ecam 134 - hisilicon,hip07-pcie-ecam 135 then: 136 properties: 137 reg: 138 maxItems: 1 139 140unevaluatedProperties: false 141 142examples: 143 - | 144 145 bus { 146 #address-cells = <2>; 147 #size-cells = <2>; 148 pcie@40000000 { 149 compatible = "pci-host-cam-generic"; 150 device_type = "pci"; 151 #address-cells = <3>; 152 #size-cells = <2>; 153 bus-range = <0x0 0x1>; 154 155 // CPU_PHYSICAL(2) SIZE(2) 156 reg = <0x0 0x40000000 0x0 0x1000000>; 157 158 // BUS_ADDRESS(3) CPU_PHYSICAL(2) SIZE(2) 159 ranges = <0x01000000 0x0 0x01000000 0x0 0x01000000 0x0 0x00010000>, 160 <0x02000000 0x0 0x41000000 0x0 0x41000000 0x0 0x3f000000>; 161 162 #interrupt-cells = <0x1>; 163 164 // PCI_DEVICE(3) INT#(1) CONTROLLER(PHANDLE) CONTROLLER_DATA(3) 165 interrupt-map = < 0x0 0x0 0x0 0x1 &gic 0x0 0x4 0x1>, 166 < 0x800 0x0 0x0 0x1 &gic 0x0 0x5 0x1>, 167 <0x1000 0x0 0x0 0x1 &gic 0x0 0x6 0x1>, 168 <0x1800 0x0 0x0 0x1 &gic 0x0 0x7 0x1>; 169 170 // PCI_DEVICE(3) INT#(1) 171 interrupt-map-mask = <0xf800 0x0 0x0 0x7>; 172 }; 173 }; 174... 175