diff options
author | Serge Semin <Sergey.Semin@baikalelectronics.ru> | 2022-11-13 22:12:51 +0300 |
---|---|---|
committer | Lorenzo Pieralisi <lpieralisi@kernel.org> | 2022-11-23 16:01:54 +0100 |
commit | 4cc13eedb892c53f3d61fb5a1f6d57724541441a (patch) | |
tree | 51cf747fbeaf3c60eab97f83fb3d1444e4b753eb /Documentation/devicetree/bindings/pci/snps,dw-pcie-ep.yaml | |
parent | 35486813c41b3a5229b4987857ff597704feda21 (diff) | |
download | linux-4cc13eedb892c53f3d61fb5a1f6d57724541441a.tar.bz2 |
dt-bindings: PCI: dwc: Add reg/reg-names common properties
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-schemas and preserving
the 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 RP/EP DT-bindings, while the already
available vendor-specific DT-bindings can still apple the common
DT-schemas.
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.
Also note since there are DW PCIe-based vendor-specific DT-bindings with
the custom names assigned to the same CSR resources we have no much choice
but to add them to the generic DT-schemas in order to have the schemas
being applicable for such devices. These names are marked as
vendor-specific and should be avoided being used in new bindings in favor
of the generic names.
Link: https://lore.kernel.org/r/20221113191301.5526-11-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Diffstat (limited to 'Documentation/devicetree/bindings/pci/snps,dw-pcie-ep.yaml')
-rw-r--r-- | Documentation/devicetree/bindings/pci/snps,dw-pcie-ep.yaml | 82 |
1 files changed, 75 insertions, 7 deletions
diff --git a/Documentation/devicetree/bindings/pci/snps,dw-pcie-ep.yaml b/Documentation/devicetree/bindings/pci/snps,dw-pcie-ep.yaml index 7d3f8fc8b7b4..f4d7eb2dec4d 100644 --- a/Documentation/devicetree/bindings/pci/snps,dw-pcie-ep.yaml +++ b/Documentation/devicetree/bindings/pci/snps,dw-pcie-ep.yaml @@ -28,18 +28,86 @@ allOf: properties: 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] + 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 + - 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 + - description: + Vendor-specific CSR names. Consider using the generic names above + for new bindings. + oneOf: + - description: See native 'elbi/app' CSR region for details. + enum: [ link, appl ] + - description: See native 'atu' CSR region for details. + enum: [ atu_dma ] + allOf: + - contains: + const: dbi + - contains: + const: addr_space interrupts: description: |