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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /Documentation/devicetree/bindings/bus/socionext,uniphier-system-bus.yaml | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'Documentation/devicetree/bindings/bus/socionext,uniphier-system-bus.yaml')
-rw-r--r-- | Documentation/devicetree/bindings/bus/socionext,uniphier-system-bus.yaml | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/bus/socionext,uniphier-system-bus.yaml b/Documentation/devicetree/bindings/bus/socionext,uniphier-system-bus.yaml new file mode 100644 index 000000000..49df13fc2 --- /dev/null +++ b/Documentation/devicetree/bindings/bus/socionext,uniphier-system-bus.yaml @@ -0,0 +1,103 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/bus/socionext,uniphier-system-bus.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: UniPhier System Bus + +description: | + The UniPhier System Bus is an external bus that connects on-board devices to + the UniPhier SoC. It is a simple (semi-)parallel bus with address, data, and + some control signals. It supports up to 8 banks (chip selects). + + Before any access to the bus, the bus controller must be configured; the bus + controller registers provide the control for the translation from the offset + within each bank to the CPU-viewed address. The needed setup includes the + base address, the size of each bank. Optionally, some timing parameters can + be optimized for faster bus access. + +maintainers: + - Masahiro Yamada <yamada.masahiro@socionext.com> + +properties: + compatible: + const: socionext,uniphier-system-bus + + reg: + maxItems: 1 + + "#address-cells": + description: | + The first cell is the bank number (chip select). + The second cell is the address offset within the bank. + const: 2 + + "#size-cells": + const: 1 + + ranges: + description: | + Provide address translation from the System Bus to the parent bus. + + Note: + The address region(s) that can be assigned for the System Bus is + implementation defined. Some SoCs can use 0x00000000-0x0fffffff and + 0x40000000-0x4fffffff, while other SoCs only 0x40000000-0x4fffffff. + There might be additional limitations depending on SoCs and the boot mode. + The address translation is arbitrary as long as the banks are assigned in + the supported address space with the required alignment and they do not + overlap one another. + + For example, it is possible to map: + bank 0 to 0x42000000-0x43ffffff, bank 5 to 0x46000000-0x46ffffff + It is also possible to map: + bank 0 to 0x48000000-0x49ffffff, bank 5 to 0x44000000-0x44ffffff + There is no reason to stick to a particular translation mapping, but the + "ranges" property should provide a "reasonable" default that is known to + work. The software should initialize the bus controller according to it. + +patternProperties: + "^.*@[1-5],[1-9a-f][0-9a-f]+$": + description: Devices attached to chip selects + type: object + +required: + - compatible + - reg + - "#address-cells" + - "#size-cells" + - ranges + +additionalProperties: false + +examples: + - | + // In this example, + // - the Ethernet device is connected at the offset 0x01f00000 of CS1 and + // mapped to 0x43f00000 of the parent bus. + // - the UART device is connected at the offset 0x00200000 of CS5 and + // mapped to 0x46200000 of the parent bus. + + system-bus@58c00000 { + compatible = "socionext,uniphier-system-bus"; + reg = <0x58c00000 0x400>; + #address-cells = <2>; + #size-cells = <1>; + ranges = <1 0x00000000 0x42000000 0x02000000>, + <5 0x00000000 0x46000000 0x01000000>; + + ethernet@1,1f00000 { + compatible = "smsc,lan9115"; + reg = <1 0x01f00000 0x1000>; + interrupts = <0 48 4>; + phy-mode = "mii"; + }; + + serial@5,200000 { + compatible = "ns16550a"; + reg = <5 0x00200000 0x20>; + interrupts = <0 49 4>; + clock-frequency = <12288000>; + }; + }; |