151 lines
5.7 KiB
Plaintext
151 lines
5.7 KiB
Plaintext
* 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.
|
|
|
|
* clock-freq-min-max (DEPRECATED): Minimum and Maximum clock frequency for card output
|
|
clock(cclk_out). If it's not specified, max is 200MHZ and min is 400KHz by default.
|
|
(Use the "max-frequency" instead of "clock-freq-min-max".)
|
|
|
|
* num-slots (DEPRECATED): specifies the number of slots supported by the controller.
|
|
The number of physical slots actually used could be equal or less than the
|
|
value specified by num-slots. If this property is not specified, the value
|
|
of num-slot property is assumed to be 1.
|
|
|
|
* 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";
|
|
};
|