kernel/linux.git/include/linux/of_address.h, branch v6.19.11

of: address: Add parent_bus_addr to struct of_pci_range

2025-01-18T21:04:23+00:00

Add a new field called 'parent_bus_addr' to struct of_pci_range to use when retrieving parent bus address information. Refer to the diagram below to better understand that the bus fabric in some systems (like i.MX8QXP) does not always use a 1:1 address map between input and output. Currently, many controller drivers use the cpu_addr_fixup() callback that would often hardcode address translation directly in the code, e.g., "cpu_addr & CDNS_PLAT_CPU_TO_BUS_ADDR" or "cpu_addr + BUS_IATU_OFFSET", etc., even though those translations *should* be described via DT. However, the cpu_addr_fixup() can be eliminated if DT correctly reflects hardware behavior and drivers use 'parent_bus_addr' in struct of_pci_range. ┌─────────┐ ┌────────────┐ ┌─────┐ │ │ IA: 0x8ff8_0000 │ │ │ CPU ├───►│ ┌────►├─────────────────┐ │ PCI │ └─────┘ │ │ │ IA: 0x8ff0_0000 │ │ │ CPU Addr │ │ ┌─►├─────────────┐ │ │ Controller │ 0x7ff8_0000─┼───┘ │ │ │ │ │ │ │ │ │ │ │ │ │ PCI Addr 0x7ff0_0000─┼──────┘ │ │ └──► IOSpace ─┼────────────► │ │ │ │ │ 0 0x7000_0000─┼────────►├─────────┐ │ │ │ └─────────┘ │ └──────► CfgSpace ─┼────────────► BUS Fabric │ │ │ 0 │ │ │ └──────────► MemSpace ─┼────────────► IA: 0x8000_0000 │ │ 0x8000_0000 └────────────┘ bus@5f000000 { compatible = "simple-bus"; #address-cells = <1>; #size-cells = <1>; ranges = <0x80000000 0x0 0x70000000 0x10000000>; pcie@5f010000 { compatible = "fsl,imx8q-pcie"; reg = <0x5f010000 0x10000>, <0x8ff00000 0x80000>; reg-names = "dbi", "config"; #address-cells = <3>; #size-cells = <2>; device_type = "pci"; bus-range = <0x00 0xff>; ranges = <0x81000000 0 0x00000000 0x8ff80000 0 0x00010000>, <0x82000000 0 0x80000000 0x80000000 0 0x0ff00000>; ... }; }; In the diagram above, the 'parent_bus_addr' field in struct of_pci_range can indicate internal address (IA) address information. Link: https://lore.kernel.org/r/20241119-pci_fixup_addr-v8-1-c4bfa5193288@nxp.com Signed-off-by: Frank Li [kwilczynski: commit log] Signed-off-by: Krzysztof Wilczyński Signed-off-by: Bjorn Helgaas Reviewed-by: Rob Herring (Arm) Acked-by: Manivannan Sadhasivam

of/address: Constify of_busses[] array and pointers

2024-10-15T13:58:36+00:00

The of_busses array is fixed, so it and all struct of_bus pointers can be const. Reviewed-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20241010-dt-const-v1-7-87a51f558425@kernel.org Signed-off-by: Rob Herring (Arm)

of: Constify struct device_node function arguments

2024-10-15T13:58:36+00:00

Functions which don't change the refcount or otherwise modify struct device_node can make struct device_node const. Reviewed-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20241010-dt-const-v1-3-87a51f558425@kernel.org Signed-off-by: Rob Herring (Arm)

of/address: Add of_property_read_reg() helper

2023-04-13T22:46:35+00:00

Add a helper, of_property_read_reg(), to read "reg" entries untranslated address and size. This function is intended mainly for cases with an untranslatable "reg" address (i.e. not MMIO). There's also a few translatable cases such as address cells containing a bus chip-select number. Link: https://lore.kernel.org/r/20230328-dt-address-helpers-v1-5-e2456c3e77ab@kernel.org Signed-off-by: Rob Herring

of/address: Add of_range_count() helper

2023-04-13T22:46:35+00:00

Some users need a count of the number of ranges entries before iterating over the entries. Typically this is for allocating some data structure based on the size. Add a helper, of_range_count(), to get the count. The helper must be called with an struct of_range_parser initialized by of_range_parser_init(). Link: https://lore.kernel.org/r/20230328-dt-address-helpers-v1-4-e2456c3e77ab@kernel.org Signed-off-by: Rob Herring

of/address: Add of_range_to_resource() helper

2023-04-13T22:46:35+00:00

A few users need to convert a specific "ranges" entry into a struct resource. Add a helper to similar to of_address_to_resource(). The existing of_pci_range_to_resource() helper isn't really PCI specific, so it can be used with the CONFIG_PCI check dropped. Link: https://lore.kernel.org/r/20230328-dt-address-helpers-v1-2-e2456c3e77ab@kernel.org Signed-off-by: Rob Herring

of: Introduce of_translate_dma_region()

2023-01-25T10:48:27+00:00

This function is similar to of_translate_dma_address() but also reads a length in addition to an address from a device tree property. Reviewed-by: Rob Herring Signed-off-by: Thierry Reding Link: https://lore.kernel.org/r/20230120174251.4004100-2-thierry.reding@gmail.com Signed-off-by: Joerg Roedel

of/address: introduce of_address_count() helper

2022-10-16T22:58:54+00:00

Introduce of_address_count() helper to count the IO resources instead of open-coding it. Signed-off-by: Yang Yingliang Link: https://lore.kernel.org/r/20221008115617.3583890-2-yangyingliang@huawei.com Signed-off-by: Rob Herring

of: address: Use IS_ENABLED() for !CONFIG_PCI

2021-06-03T01:59:29+00:00

Convert address.c to use IS_ENABLED() instead of ifdefs for the public PCI functions. This simplifies the ifdefs in of_address.h. Cc: Frank Rowand Signed-off-by: Rob Herring Link: https://lore.kernel.org/r/20210527194547.1287934-4-robh@kernel.org

of: Merge of_get_address() and of_get_pci_address() implementations

2021-06-03T01:59:28+00:00

of_get_address() and of_get_pci_address() are the same implementation except of_get_pci_address() takes the PCI BAR number rather than an index. Modify the of_get_address() implementation to work on either index or BAR and provide wrapper functions for the existing functions. Cc: Frank Rowand Signed-off-by: Rob Herring Link: https://lore.kernel.org/r/20210527194547.1287934-3-robh@kernel.org