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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/devicetree/bindings/serial/snps-dw-apb-uart.txt
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
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+* Synopsys DesignWare ABP UART
+
+Required properties:
+- compatible : "snps,dw-apb-uart"
+- reg : offset and length of the register set for the device.
+- interrupts : should contain uart interrupt.
+
+Clock handling:
+The clock rate of the input clock needs to be supplied by one of
+- clock-frequency : the input clock frequency for the UART.
+- clocks : phandle to the input clock
+
+The supplying peripheral clock can also be handled, needing a second property
+- clock-names: tuple listing input clock names.
+ Required elements: "baudclk", "apb_pclk"
+
+Optional properties:
+- resets : phandle to the parent reset controller.
+- reg-shift : quantity to shift the register offsets by. If this property is
+ not present then the register offsets are not shifted.
+- reg-io-width : the size (in bytes) of the IO accesses that should be
+ performed on the device. If this property is not present then single byte
+ accesses are used.
+- dcd-override : Override the DCD modem status signal. This signal will always
+ be reported as active instead of being obtained from the modem status
+ register. Define this if your serial port does not use this pin.
+- dsr-override : Override the DTS modem status signal. This signal will always
+ be reported as active instead of being obtained from the modem status
+ register. Define this if your serial port does not use this pin.
+- cts-override : Override the CTS modem status signal. This signal will always
+ be reported as active instead of being obtained from the modem status
+ register. Define this if your serial port does not use this pin.
+- ri-override : Override the RI modem status signal. This signal will always be
+ reported as inactive instead of being obtained from the modem status register.
+ Define this if your serial port does not use this pin.
+
+Example:
+
+ uart@80230000 {
+ compatible = "snps,dw-apb-uart";
+ reg = <0x80230000 0x100>;
+ clock-frequency = <3686400>;
+ interrupts = <10>;
+ reg-shift = <2>;
+ reg-io-width = <4>;
+ dcd-override;
+ dsr-override;
+ cts-override;
+ ri-override;
+ };
+
+Example with one clock:
+
+ uart@80230000 {
+ compatible = "snps,dw-apb-uart";
+ reg = <0x80230000 0x100>;
+ clocks = <&baudclk>;
+ interrupts = <10>;
+ reg-shift = <2>;
+ reg-io-width = <4>;
+ };
+
+Example with two clocks:
+
+ uart@80230000 {
+ compatible = "snps,dw-apb-uart";
+ reg = <0x80230000 0x100>;
+ clocks = <&baudclk>, <&apb_pclk>;
+ clock-names = "baudclk", "apb_pclk";
+ interrupts = <10>;
+ reg-shift = <2>;
+ reg-io-width = <4>;
+ };