From adf38bb0b5956ab5469acb1ca981a9287c7ad1d8 Mon Sep 17 00:00:00 2001 From: Zhichang Yuan Date: Wed, 21 Mar 2018 17:23:02 -0500 Subject: HISI LPC: Support the LPC host on Hip06/Hip07 with DT bindings The low-pin-count (LPC) interface of Hip06/Hip07 accesses I/O port space of peripherals. Implement the LPC host controller driver which performs the I/O operations on the underlying hardware. We don't want to touch existing drivers such as ipmi-bt, so this driver applies the indirect-IO introduced in the previous patch after registering an indirect-IO node to the indirect-IO devices list which will be searched by the I/O accessors to retrieve the host-local I/O port. The driver config is set as a bool instead of a tristate. The reason here is that, by the very nature of the driver providing a logical PIO range, it does not make sense to have this driver as a loadable module. Another more specific reason is that the Huawei D03 board which includes Hip06 SoC requires the LPC bus for UART console, so should be built in. Tested-by: dann frazier Signed-off-by: Zou Rongrong Signed-off-by: Zhichang Yuan Signed-off-by: John Garry Signed-off-by: Bjorn Helgaas Reviewed-by: Andy Shevchenko Acked-by: Rob Herring # dts part --- .../arm/hisilicon/hisilicon-low-pin-count.txt | 33 ++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt (limited to 'Documentation/devicetree') diff --git a/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt b/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt new file mode 100644 index 000000000000..10bd35f9207f --- /dev/null +++ b/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt @@ -0,0 +1,33 @@ +Hisilicon Hip06 Low Pin Count device + Hisilicon Hip06 SoCs implement a Low Pin Count (LPC) controller, which + provides I/O access to some legacy ISA devices. + Hip06 is based on arm64 architecture where there is no I/O space. So, the + I/O ports here are not CPU addresses, and there is no 'ranges' property in + LPC device node. + +Required properties: +- compatible: value should be as follows: + (a) "hisilicon,hip06-lpc" + (b) "hisilicon,hip07-lpc" +- #address-cells: must be 2 which stick to the ISA/EISA binding doc. +- #size-cells: must be 1 which stick to the ISA/EISA binding doc. +- reg: base memory range where the LPC register set is mapped. + +Note: + The node name before '@' must be "isa" to represent the binding stick to the + ISA/EISA binding specification. + +Example: + +isa@a01b0000 { + compatible = "hisilicon,hip06-lpc"; + #address-cells = <2>; + #size-cells = <1>; + reg = <0x0 0xa01b0000 0x0 0x1000>; + + ipmi0: bt@e4 { + compatible = "ipmi-bt"; + device_type = "ipmi"; + reg = <0x01 0xe4 0x04>; + }; +}; -- cgit v1.2.3