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authorZhichang Yuan <yuanzhichang@hisilicon.com>2018-03-22 01:23:02 +0300
committerBjorn Helgaas <helgaas@kernel.org>2018-04-04 16:42:48 +0300
commitadf38bb0b5956ab5469acb1ca981a9287c7ad1d8 (patch)
treec08d2e7f88c69883ae7aff65647e0c9d9589e928 /Documentation/devicetree/bindings/arm
parent65af618d2c559f8eb19d80d03a23029651a59de4 (diff)
downloadlinux-adf38bb0b5956ab5469acb1ca981a9287c7ad1d8.tar.xz
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 <dann.frazier@canonical.com> Signed-off-by: Zou Rongrong <zourongrong@huawei.com> Signed-off-by: Zhichang Yuan <yuanzhichang@hisilicon.com> Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Rob Herring <robh@kernel.org> # dts part
Diffstat (limited to 'Documentation/devicetree/bindings/arm')
-rw-r--r--Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt33
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diff --git a/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt b/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt
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+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>;
+ };
+};