About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Documentation / devicetree / bindings / net / fsl-tsec-phy.txt




Custom Search

Based on kernel version 4.8. Page generated on 2016-10-06 23:13 EST.

1	* MDIO IO device
2	
3	The MDIO is a bus to which the PHY devices are connected.  For each
4	device that exists on this bus, a child node should be created.  See
5	the definition of the PHY node in booting-without-of.txt for an example
6	of how to define a PHY.
7	
8	Required properties:
9	  - reg : Offset and length of the register set for the device
10	  - compatible : Should define the compatible device type for the
11	    mdio. Currently supported strings/devices are:
12		- "fsl,gianfar-tbi"
13		- "fsl,gianfar-mdio"
14		- "fsl,etsec2-tbi"
15		- "fsl,etsec2-mdio"
16		- "fsl,ucc-mdio"
17		- "fsl,fman-mdio"
18	    When device_type is "mdio", the following strings are also considered:
19		- "gianfar"
20		- "ucc_geth_phy"
21	
22	Example:
23	
24		mdio@24520 {
25			reg = <24520 20>;
26			compatible = "fsl,gianfar-mdio";
27	
28			ethernet-phy@0 {
29				......
30			};
31		};
32	
33	* TBI Internal MDIO bus
34	
35	As of this writing, every tsec is associated with an internal TBI PHY.
36	This PHY is accessed through the local MDIO bus.  These buses are defined
37	similarly to the mdio buses, except they are compatible with "fsl,gianfar-tbi".
38	The TBI PHYs underneath them are similar to normal PHYs, but the reg property
39	is considered instructive, rather than descriptive.  The reg property should
40	be chosen so it doesn't interfere with other PHYs on the bus.
41	
42	* Gianfar-compatible ethernet nodes
43	
44	Properties:
45	
46	  - device_type : Should be "network"
47	  - model : Model of the device.  Can be "TSEC", "eTSEC", or "FEC"
48	  - compatible : Should be "gianfar"
49	  - reg : Offset and length of the register set for the device
50	  - interrupts : For FEC devices, the first interrupt is the device's
51	    interrupt.  For TSEC and eTSEC devices, the first interrupt is
52	    transmit, the second is receive, and the third is error.
53	  - phy-handle : See ethernet.txt file in the same directory.
54	  - fixed-link : See fixed-link.txt in the same directory.
55	  - phy-connection-type : See ethernet.txt file in the same directory.
56	    This property is only really needed if the connection is of type
57	    "rgmii-id", as all other connection types are detected by hardware.
58	  - fsl,magic-packet : If present, indicates that the hardware supports
59	    waking up via magic packet.
60	  - fsl,wake-on-filer : If present, indicates that the hardware supports
61	    waking up by Filer General Purpose Interrupt (FGPI) asserted on the
62	    Rx int line.  This is an advanced power management capability allowing
63	    certain packet types (user) defined by filer rules to wake up the system.
64	  - bd-stash : If present, indicates that the hardware supports stashing
65	    buffer descriptors in the L2.
66	  - rx-stash-len : Denotes the number of bytes of a received buffer to stash
67	    in the L2.
68	  - rx-stash-idx : Denotes the index of the first byte from the received
69	    buffer to stash in the L2.
70	
71	Example:
72		ethernet@24000 {
73			device_type = "network";
74			model = "TSEC";
75			compatible = "gianfar";
76			reg = <0x24000 0x1000>;
77			local-mac-address = [ 00 E0 0C 00 73 00 ];
78			interrupts = <29 2 30 2 34 2>;
79			interrupt-parent = <&mpic>;
80			phy-handle = <&phy0>
81		};
82	
83	* Gianfar PTP clock nodes
84	
85	General Properties:
86	
87	  - compatible   Should be "fsl,etsec-ptp"
88	  - reg          Offset and length of the register set for the device
89	  - interrupts   There should be at least two interrupts. Some devices
90	                 have as many as four PTP related interrupts.
91	
92	Clock Properties:
93	
94	  - fsl,cksel        Timer reference clock source.
95	  - fsl,tclk-period  Timer reference clock period in nanoseconds.
96	  - fsl,tmr-prsc     Prescaler, divides the output clock.
97	  - fsl,tmr-add      Frequency compensation value.
98	  - fsl,tmr-fiper1   Fixed interval period pulse generator.
99	  - fsl,tmr-fiper2   Fixed interval period pulse generator.
100	  - fsl,max-adj      Maximum frequency adjustment in parts per billion.
101	
102	  These properties set the operational parameters for the PTP
103	  clock. You must choose these carefully for the clock to work right.
104	  Here is how to figure good values:
105	
106	  TimerOsc     = selected reference clock   MHz
107	  tclk_period  = desired clock period       nanoseconds
108	  NominalFreq  = 1000 / tclk_period         MHz
109	  FreqDivRatio = TimerOsc / NominalFreq     (must be greater that 1.0)
110	  tmr_add      = ceil(2^32 / FreqDivRatio)
111	  OutputClock  = NominalFreq / tmr_prsc     MHz
112	  PulseWidth   = 1 / OutputClock            microseconds
113	  FiperFreq1   = desired frequency in Hz
114	  FiperDiv1    = 1000000 * OutputClock / FiperFreq1
115	  tmr_fiper1   = tmr_prsc * tclk_period * FiperDiv1 - tclk_period
116	  max_adj      = 1000000000 * (FreqDivRatio - 1.0) - 1
117	
118	  The calculation for tmr_fiper2 is the same as for tmr_fiper1. The
119	  driver expects that tmr_fiper1 will be correctly set to produce a 1
120	  Pulse Per Second (PPS) signal, since this will be offered to the PPS
121	  subsystem to synchronize the Linux clock.
122	
123	  Reference clock source is determined by the value, which is holded
124	  in CKSEL bits in TMR_CTRL register. "fsl,cksel" property keeps the
125	  value, which will be directly written in those bits, that is why,
126	  according to reference manual, the next clock sources can be used:
127	
128	  <0> - external high precision timer reference clock (TSEC_TMR_CLK
129	        input is used for this purpose);
130	  <1> - eTSEC system clock;
131	  <2> - eTSEC1 transmit clock;
132	  <3> - RTC clock input.
133	
134	  When this attribute is not used, eTSEC system clock will serve as
135	  IEEE 1588 timer reference clock.
136	
137	Example:
138	
139		ptp_clock@24E00 {
140			compatible = "fsl,etsec-ptp";
141			reg = <0x24E00 0xB0>;
142			interrupts = <12 0x8 13 0x8>;
143			interrupt-parent = < &ipic >;
144			fsl,cksel       = <1>;
145			fsl,tclk-period = <10>;
146			fsl,tmr-prsc    = <100>;
147			fsl,tmr-add     = <0x999999A4>;
148			fsl,tmr-fiper1  = <0x3B9AC9F6>;
149			fsl,tmr-fiper2  = <0x00018696>;
150			fsl,max-adj     = <659999998>;
151		};
Hide Line Numbers
About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Information is copyright its respective author. All material is available from the Linux Kernel Source distributed under a GPL License. This page is provided as a free service by mjmwired.net.