Even though there is a more-or-less limited set of the CSR spaces can be defined for each DW PCIe controller the generic DT schema currently doesn't specify much limitations on the reg-space names used for one or another range. In order to prevent the vendor-specific controller schemas further deviation from the generic interface let's fix that by introducing the reg-names definition in the common DW PCIe DT-schema and preserving a generic "reg" and "reg-names" properties in there. New DW PCIe device DT-bindings are encouraged to use the generic set of the CSR spaces defined in the generic DW PCie DT-bindings, while the already available vendor-specific DT-bindings can refer to the common schema and define their own reg-spaces. Note the number of reg/reg-names items need to be changed in the DW PCIe EP DT-schema since aside with the "dbi" CSRs space these arrays can have "dbi2", "addr_space", "atu", etc ranges. Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx> --- Changelog v3: - This is a new patch unpinned from the next one: https://lore.kernel.org/linux-pci/20220503214638.1895-2-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx/ by the Rob' request. (@Rob) - Split up reg-names in the same way as the interrupt-names: common, Root Port and Endpoint specific names. (@Rob) - Drop synonymous from the names list since the device schemas create their own enumerations anyway. --- .../bindings/pci/snps,dw-pcie-common.yaml | 76 +++++++++++++++++++ .../bindings/pci/snps,dw-pcie-ep.yaml | 34 +++++++-- .../devicetree/bindings/pci/snps,dw-pcie.yaml | 27 +++++-- 3 files changed, 124 insertions(+), 13 deletions(-) diff --git a/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml b/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml index 0a524e916a9f..c6a55f90ddd5 100644 --- a/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml +++ b/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml @@ -17,6 +17,28 @@ description: select: false properties: + reg: + description: + DWC PCIe CSR space is normally accessed over the dedicated Data Bus + Interface - DBI. In accordance with the reference manual the register + configuration space belongs to the Configuration-Dependent Module (CDM) + and is split up into several sub-parts Standard PCIe configuration + space, Port Logic Registers (PL), Shadow Config-space Registers, + iATU/eDMA registers. The particular sub-space is selected by the + CDM/ELBI (dbi_cs) and CS2 (dbi_cs2) signals (selector bits). Such + configuration provides a flexible interface for the system engineers to + either map the particular space at a desired MMIO address or just leave + them in a contiguous memory space if pure Native or AXI Bridge DBI access + is selected. Note the PCIe CFG-space, PL and Shadow registers are + specific for each activated function, while the rest of the sub-spaces + are common for all of them (if there are more than one). + minItems: 2 + maxItems: 6 + + reg-names: + minItems: 2 + maxItems: 6 + interrupts: description: There are two main sub-blocks which are normally capable of @@ -111,6 +133,60 @@ properties: additionalProperties: true definitions: + reg-names: + description: + CSR space names common for the DWC PCIe Root Port and Endpoint + controllers. + oneOf: + - description: + Basic DWC PCIe controller configuration-space accessible over + the DBI interface. This memory space is either activated with + CDM/ELBI = 0 and CS2 = 0 or is a contiguous memory region + with all spaces. Note iATU/eDMA CSRs are indirectly accessible + via the PL viewports on the DWC PCIe controllers older than + v4.80a. + const: dbi + - description: + Shadow DWC PCIe config-space registers. This space is selected + by setting CDM/ELBI = 0 and CS2 = 1. This is an intermix of + the PCI-SIG PCIe CFG-space with the shadow registers for some + PCI Header space, PCI Standard and Extended Structures. It's + mainly relevant for the end-point controller configuration, + but still there are some shadow registers available for the + Root Port mode too. + const: dbi2 + - description: + External Local Bus registers. It's an application-dependent + registers normally defined by the platform engineers. The space + can be selected by setting CDM/ELBI = 1 and CS2 = 0 wires or can + be accessed over some platform-specific means (for instance + as a part of a system controller). + enum: [ elbi, app ] + - description: + iATU/eDMA registers common for all device functions. It's an + unrolled memory space with the internal Address Translation + Unit and Enhanced DMA, which is selected by setting CDM/ELBI = 1 + and CS2 = 1. For IP-core releases prior v4.80a, these registers + have been programmed via an indirect addressing scheme using a + set of viewport CSRs mapped into the PL space. Note iATU is + normally mapped to the 0x0 address of this region, while eDMA + is available at 0x80000 base address. + const: atu + - description: + Platform-specific eDMA registers. Some platforms may have eDMA + CSRs mapped in a non-standard base address. The registers offset + can be changed or the MS/LS-bits of the address can be attached + in an additional RTL block before the MEM-IO transactions reach + the DW PCIe slave interface. + const: dma + - description: + PHY/PCS configuration registers. Some platforms can have the + PCS and PHY CSRs accessible over a dedicated memory mapped + region, but mainly these registers are indirectly accessible + either by means of the embedded PHY viewport schema or by some + platform-specific method. + const: phy + interrupt-names: description: IRQ signal names common for the DWC PCIe Root Port and Endpoint diff --git a/Documentation/devicetree/bindings/pci/snps,dw-pcie-ep.yaml b/Documentation/devicetree/bindings/pci/snps,dw-pcie-ep.yaml index 5f12a6ac08d8..bfff723b529d 100644 --- a/Documentation/devicetree/bindings/pci/snps,dw-pcie-ep.yaml +++ b/Documentation/devicetree/bindings/pci/snps,dw-pcie-ep.yaml @@ -40,18 +40,25 @@ properties: const: snps,dw-pcie-ep reg: - description: | - It should contain Data Bus Interface (dbi) and config registers for all - versions. - For designware core version >= 4.80, it may contain ATU address space. + description: + DBI, DBI2 reg-spaces and outbound memory window are required for the + normal controller functioning. iATU memory IO region is also required + if the space is unrolled (IP-core version >= 4.80a). minItems: 2 - maxItems: 4 + maxItems: 5 reg-names: minItems: 2 - maxItems: 4 + maxItems: 5 items: - enum: [dbi, dbi2, config, atu, addr_space, link, atu_dma, appl] + anyOf: + - $ref: /schemas/pci/snps,dw-pcie-common.yaml#/definitions/reg-names + - $ref: '#/definitions/reg-names' + allOf: + - contains: + const: dbi + - contains: + const: addr_space interrupts: description: @@ -77,6 +84,19 @@ required: additionalProperties: true +definitions: + reg-names: + description: + DWC PCIe Endpoint specific CSR space names. + oneOf: + - description: + Outbound iATU-capable memory-region which will be used to + generate various application-specific traffic on the PCIe bus + hierarchy. It's usage scenario depends on the endpoint + functionality, for instance it can be used to create MSI(X) + messages. + const: addr_space + examples: - | pcie-ep@dfd00000 { diff --git a/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml b/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml index e0020b72288a..9e96c6d0ef48 100644 --- a/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml +++ b/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml @@ -40,10 +40,10 @@ properties: const: snps,dw-pcie reg: - description: | - It should contain Data Bus Interface (dbi) and config registers for all - versions. - For designware core version >= 4.80, it may contain ATU address space. + description: + At least DBI reg-space and peripheral devices CFG-space outbound window + are required for the normal controller work. iATU memory IO region is + also required if the space is unrolled (IP-core version >= 4.80a). minItems: 2 maxItems: 5 @@ -51,8 +51,14 @@ properties: minItems: 2 maxItems: 5 items: - enum: [ dbi, dbi2, config, atu, app, elbi, mgmt, ctrl, parf, cfg, link, - ulreg, smu, mpu, apb, phy ] + anyOf: + - $ref: /schemas/pci/snps,dw-pcie-common.yaml#/definitions/reg-names + - $ref: '#/definitions/reg-names' + allOf: + - contains: + const: dbi + - contains: + const: config interrupts: description: @@ -82,6 +88,15 @@ required: - reg-names definitions: + reg-names: + description: + DWC PCIe Root Port/Complex specific CSR space names. + oneOf: + - description: + Outbound iATU-capable memory-region which will be used to access + the peripheral PCIe devices configuration space. + const: config + interrupt-names: description: DWC PCIe Root Port/Complex specific IRQ signal names. -- 2.35.1
