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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
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Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+* Synopsys Designware Mobile Storage Host Controller
+
+The Synopsys designware mobile storage host controller is used to interface
+a SoC with storage medium such as eMMC or SD/MMC cards. This file documents
+differences between the core mmc properties described by mmc.txt and the
+properties used by the Synopsys Designware Mobile Storage Host Controller.
+
+Required Properties:
+
+* compatible: should be
+ - snps,dw-mshc: for controllers compliant with synopsys dw-mshc.
+* #address-cells: should be 1.
+* #size-cells: should be 0.
+
+# Slots (DEPRECATED): The slot specific information are contained within
+ child-nodes with each child-node representing a supported slot. There should
+ be atleast one child node representing a card slot. The name of the child node
+ representing the slot is recommended to be slot@n where n is the unique number
+ of the slot connected to the controller. The following are optional properties
+ which can be included in the slot child node.
+
+ * reg: specifies the physical slot number. The valid values of this
+ property is 0 to (num-slots -1), where num-slots is the value
+ specified by the num-slots property.
+
+ * bus-width: as documented in mmc core bindings.
+
+ * wp-gpios: specifies the write protect gpio line. The format of the
+ gpio specifier depends on the gpio controller. If a GPIO is not used
+ for write-protect, this property is optional.
+
+ * disable-wp: If the wp-gpios property isn't present then (by default)
+ we'd assume that the write protect is hooked up directly to the
+ controller's special purpose write protect line (accessible via
+ the WRTPRT register). However, it's possible that we simply don't
+ want write protect. In that case specify 'disable-wp'.
+ NOTE: This property is not required for slots known to always
+ connect to eMMC or SDIO cards.
+
+Optional properties:
+
+* resets: phandle + reset specifier pair, intended to represent hardware
+ reset signal present internally in some host controller IC designs.
+ See Documentation/devicetree/bindings/reset/reset.txt for details.
+
+* reset-names: request name for using "resets" property. Must be "reset".
+ (It will be used together with "resets" property.)
+
+* clocks: from common clock binding: handle to biu and ciu clocks for the
+ bus interface unit clock and the card interface unit clock.
+
+* clock-names: from common clock binding: Shall be "biu" and "ciu".
+ If the biu clock is missing we'll simply skip enabling it. If the
+ ciu clock is missing we'll just assume that the clock is running at
+ clock-frequency. It is an error to omit both the ciu clock and the
+ clock-frequency.
+
+* clock-frequency: should be the frequency (in Hz) of the ciu clock. If this
+ is specified and the ciu clock is specified then we'll try to set the ciu
+ clock to this at probe time.
+
+* fifo-depth: The maximum size of the tx/rx fifo's. If this property is not
+ specified, the default value of the fifo size is determined from the
+ controller registers.
+
+* card-detect-delay: Delay in milli-seconds before detecting card after card
+ insert event. The default value is 0.
+
+* data-addr: Override fifo address with value provided by DT. The default FIFO reg
+ offset is assumed as 0x100 (version < 0x240A) and 0x200(version >= 0x240A) by
+ driver. If the controller does not follow this rule, please use this property
+ to set fifo address in device tree.
+
+* fifo-watermark-aligned: Data done irq is expected if data length is less than
+ watermark in PIO mode. But fifo watermark is requested to be aligned with data
+ length in some SoC so that TX/RX irq can be generated with data done irq. Add this
+ watermark quirk to mark this requirement and force fifo watermark setting
+ accordingly.
+
+* vmmc-supply: The phandle to the regulator to use for vmmc. If this is
+ specified we'll defer probe until we can find this regulator.
+
+* dmas: List of DMA specifiers with the controller specific format as described
+ in the generic DMA client binding. Refer to dma.txt for details.
+
+* dma-names: request names for generic DMA client binding. Must be "rx-tx".
+ Refer to dma.txt for details.
+
+Aliases:
+
+- All the MSHC controller nodes should be represented in the aliases node using
+ the following format 'mshc{n}' where n is a unique number for the alias.
+
+Example:
+
+The MSHC controller node can be split into two portions, SoC specific and
+board specific portions as listed below.
+
+ dwmmc0@12200000 {
+ compatible = "snps,dw-mshc";
+ clocks = <&clock 351>, <&clock 132>;
+ clock-names = "biu", "ciu";
+ reg = <0x12200000 0x1000>;
+ interrupts = <0 75 0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ data-addr = <0x200>;
+ fifo-watermark-aligned;
+ resets = <&rst 20>;
+ reset-names = "reset";
+ };
+
+[board specific internal DMA resources]
+
+ dwmmc0@12200000 {
+ clock-frequency = <400000000>;
+ clock-freq-min-max = <400000 200000000>;
+ broken-cd;
+ fifo-depth = <0x80>;
+ card-detect-delay = <200>;
+ vmmc-supply = <&buck8>;
+ bus-width = <8>;
+ cap-mmc-highspeed;
+ cap-sd-highspeed;
+ };
+
+[board specific generic DMA request binding]
+
+ dwmmc0@12200000 {
+ clock-frequency = <400000000>;
+ clock-freq-min-max = <400000 200000000>;
+ broken-cd;
+ fifo-depth = <0x80>;
+ card-detect-delay = <200>;
+ vmmc-supply = <&buck8>;
+ bus-width = <8>;
+ cap-mmc-highspeed;
+ cap-sd-highspeed;
+ dmas = <&pdma 12>;
+ dma-names = "rx-tx";
+ };