diff options
Diffstat (limited to 'Documentation/devicetree/bindings/serial')
5 files changed, 127 insertions, 34 deletions
diff --git a/Documentation/devicetree/bindings/serial/fsl,s32-linflexuart.txt b/Documentation/devicetree/bindings/serial/fsl,s32-linflexuart.txt new file mode 100644 index 000000000000..f1bbe0826be5 --- /dev/null +++ b/Documentation/devicetree/bindings/serial/fsl,s32-linflexuart.txt @@ -0,0 +1,22 @@ +* Freescale LINFlexD UART + +The LINFlexD controller implements several LIN protocol versions, as well as +support for full-duplex UART communication through 8-bit and 9-bit frames. + +See chapter 47 ("LINFlexD") in the reference manual[1]. + +Required properties: +- compatible : + - "fsl,s32v234-linflexuart" for LINFlexD configured in UART mode, which + is compatible with the one integrated on S32V234 SoC +- reg : Address and length of the register set for the device +- interrupts : Should contain uart interrupt + +Example: +uart0: serial@40053000 { + compatible = "fsl,s32v234-linflexuart"; + reg = <0x0 0x40053000 0x0 0x1000>; + interrupts = <0 59 4>; +}; + +[1] https://www.nxp.com/webapp/Download?colCode=S32V234RM diff --git a/Documentation/devicetree/bindings/serial/nvidia,tegra20-hsuart.txt b/Documentation/devicetree/bindings/serial/nvidia,tegra20-hsuart.txt index d7edf732eb7f..f709304036c2 100644 --- a/Documentation/devicetree/bindings/serial/nvidia,tegra20-hsuart.txt +++ b/Documentation/devicetree/bindings/serial/nvidia,tegra20-hsuart.txt @@ -1,7 +1,12 @@ NVIDIA Tegra20/Tegra30 high speed (DMA based) UART controller driver. Required properties: -- compatible : should be "nvidia,tegra30-hsuart", "nvidia,tegra20-hsuart". +- compatible : should be, + "nvidia,tegra20-hsuart" for Tegra20, + "nvidia,tegra30-hsuart" for Tegra30, + "nvidia,tegra186-hsuart" for Tegra186, + "nvidia,tegra194-hsuart" for Tegra194. + - reg: Should contain UART controller registers location and length. - interrupts: Should contain UART controller interrupts. - clocks: Must contain one entry, for the module clock. @@ -19,6 +24,37 @@ Required properties: Optional properties: - nvidia,enable-modem-interrupt: Enable modem interrupts. Should be enable only if all 8 lines of UART controller are pinmuxed. +- nvidia,adjust-baud-rates: List of entries providing percentage of baud rate + adjustment within a range. + Each entry contains sets of 3 values. Range low/high and adjusted rate. + <range_low range_high adjusted_rate> + When baud rate set on controller falls within the range mentioned in this + field, baud rate will be adjusted by percentage mentioned here. + Ex: <9600 115200 200> + Increase baud rate by 2% when set baud rate falls within range 9600 to 115200 + +Baud Rate tolerance: + Standard UART devices are expected to have tolerance for baud rate error by + -4 to +4 %. All Tegra devices till Tegra210 had this support. However, + Tegra186 chip has a known hardware issue. UART Rx baud rate tolerance level + is 0% to +4% in 1-stop config. Otherwise, the received data will have + corruption/invalid framing errors. Parker errata suggests adjusting baud + rate to be higher than the deviations observed in Tx. + + Tx deviation of connected device can be captured over scope (or noted from + its spec) for valid range and Tegra baud rate has to be set above actual + Tx baud rate observed. To do this we use nvidia,adjust-baud-rates + + As an example, consider there is deviation observed in Tx for baud rates as + listed below. + 0 to 9600 has 1% deviation + 9600 to 115200 2% deviation + This slight deviation is expcted and Tegra UART is expected to handle it. Due + to the issue stated above, baud rate on Tegra UART should be set equal to or + above deviation observed for avoiding frame errors. + Property should be set like this + nvidia,adjust-baud-rates = <0 9600 100>, + <9600 115200 200>; Example: @@ -33,4 +69,5 @@ serial@70006000 { reset-names = "serial"; dmas = <&apbdma 8>, <&apbdma 8>; dma-names = "rx", "tx"; + nvidia,adjust-baud-rates = <1000000 4000000 136>; /* 1.36% shift */ }; diff --git a/Documentation/devicetree/bindings/serial/sifive-serial.txt b/Documentation/devicetree/bindings/serial/sifive-serial.txt deleted file mode 100644 index c86b1e524159..000000000000 --- a/Documentation/devicetree/bindings/serial/sifive-serial.txt +++ /dev/null @@ -1,33 +0,0 @@ -SiFive asynchronous serial interface (UART) - -Required properties: - -- compatible: should be something similar to - "sifive,<chip>-uart" for the UART as integrated - on a particular chip, and "sifive,uart<version>" for the - general UART IP block programming model. Supported - compatible strings as of the date of this writing are: - "sifive,fu540-c000-uart" for the SiFive UART v0 as - integrated onto the SiFive FU540 chip, or "sifive,uart0" - for the SiFive UART v0 IP block with no chip integration - tweaks (if any) -- reg: address and length of the register space -- interrupts: Should contain the UART interrupt identifier -- clocks: Should contain a clock identifier for the UART's parent clock - - -UART HDL that corresponds to the IP block version numbers can be found -here: - -https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/uart - - -Example: - -uart0: serial@10010000 { - compatible = "sifive,fu540-c000-uart", "sifive,uart0"; - interrupt-parent = <&plic0>; - interrupts = <80>; - reg = <0x0 0x10010000 0x0 0x1000>; - clocks = <&prci PRCI_CLK_TLCLK>; -}; diff --git a/Documentation/devicetree/bindings/serial/sifive-serial.yaml b/Documentation/devicetree/bindings/serial/sifive-serial.yaml new file mode 100644 index 000000000000..e8d3aeda1202 --- /dev/null +++ b/Documentation/devicetree/bindings/serial/sifive-serial.yaml @@ -0,0 +1,62 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/serial/sifive-serial.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: SiFive asynchronous serial interface (UART) + +maintainers: + - Pragnesh Patel <pragnesh.patel@sifive.com> + - Paul Walmsley <paul.walmsley@sifive.com> + - Palmer Dabbelt <palmer@sifive.com> + +allOf: + - $ref: /schemas/serial.yaml# + +properties: + compatible: + items: + - const: sifive,fu540-c000-uart + - const: sifive,uart0 + + description: + Should be something similar to "sifive,<chip>-uart" + for the UART as integrated on a particular chip, + and "sifive,uart<version>" for the general UART IP + block programming model. + + UART HDL that corresponds to the IP block version + numbers can be found here - + + https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/uart + + reg: + maxItems: 1 + + interrupts: + maxItems: 1 + + clocks: + maxItems: 1 + +required: + - compatible + - reg + - interrupts + - clocks + +additionalProperties: false + +examples: + - | + #include <dt-bindings/clock/sifive-fu540-prci.h> + serial@10010000 { + compatible = "sifive,fu540-c000-uart", "sifive,uart0"; + interrupt-parent = <&plic0>; + interrupts = <80>; + reg = <0x0 0x10010000 0x0 0x1000>; + clocks = <&prci PRCI_CLK_TLCLK>; + }; + +... diff --git a/Documentation/devicetree/bindings/serial/st,stm32-usart.txt b/Documentation/devicetree/bindings/serial/st,stm32-usart.txt index a6b19485c9dc..8620f7fcbd50 100644 --- a/Documentation/devicetree/bindings/serial/st,stm32-usart.txt +++ b/Documentation/devicetree/bindings/serial/st,stm32-usart.txt @@ -20,6 +20,11 @@ Optional properties: linux,rs485-enabled-at-boot-time: see rs485.txt. - dmas: phandle(s) to DMA controller node(s). Refer to stm32-dma.txt - dma-names: "rx" and/or "tx" +- wakeup-source: bool flag to indicate this device has wakeup capabilities +- interrupt-names, if optional wake-up interrupt is used, should be: + - "event": the name for the interrupt line of the USART instance + - "wakeup" the name for the optional wake-up interrupt + Examples: usart4: serial@40004c00 { |