Booting the Linux/ppc kernel without Open Firmware
--------------------------------------------------
-
(c) 2005 Benjamin Herrenschmidt <benh at kernel.crashing.org>,
IBM Corp.
(c) 2005 Becky Bruce <becky.bruce at freescale.com>,
(c) 2006 MontaVista Software, Inc.
Flash chip node definition
+Table of Contents
+=================
+
+ I - Introduction
+ 1) Entry point for arch/powerpc
+ 2) Board support
+
+ II - The DT block format
+ 1) Header
+ 2) Device tree generalities
+ 3) Device tree "structure" block
+ 4) Device tree "strings" block
+
+ III - Required content of the device tree
+ 1) Note about cells and address representation
+ 2) Note about "compatible" properties
+ 3) Note about "name" properties
+ 4) Note about node and property names and character set
+ 5) Required nodes and properties
+ a) The root node
+ b) The /cpus node
+ c) The /cpus/* nodes
+ d) the /memory node(s)
+ e) The /chosen node
+ f) the /soc<SOCname> node
+
+ IV - "dtc", the device tree compiler
+
+ V - Recommendations for a bootloader
+
+ VI - System-on-a-chip devices and nodes
+ 1) Defining child nodes of an SOC
+ 2) Representing devices without a current OF specification
+ a) MDIO IO device
+ c) PHY nodes
+ b) Gianfar-compatible ethernet nodes
+ d) Interrupt controllers
+ e) I2C
+ f) Freescale SOC USB controllers
+ g) Freescale SOC SEC Security Engines
+ h) Board Control and Status (BCSR)
+ i) Freescale QUICC Engine module (QE)
+ g) Flash chip nodes
+
+ VII - Specifying interrupt information for devices
+ 1) interrupts property
+ 2) interrupt-parent property
+ 3) OpenPIC Interrupt Controllers
+ 4) ISA Interrupt Controllers
+
+ Appendix A - Sample SOC node for MPC8540
+
+
+Revision Information
+====================
+
May 18, 2005: Rev 0.1 - Initial draft, no chapter III yet.
May 19, 2005: Rev 0.2 - Add chapter III and bits & pieces here or
Basically, it is a bus of devices, that could act more or less
as a complete entity (UCC, USB etc ). All of them should be siblings on
the "root" qe node, using the common properties from there.
- The description below applies to the the qe of MPC8360 and
+ The description below applies to the qe of MPC8360 and
more nodes and properties would be extended in the future.
i) Root QE device
network device. This is used by the bootwrapper to interpret
MAC addresses passed by the firmware when no information other
than indices is available to associate an address with a device.
+ - phy-connection-type : a string naming the controller/PHY interface type,
+ i.e., "mii" (default), "rmii", "gmii", "rgmii", "rgmii-id", "tbi",
+ or "rtbi".
Example:
ucc@2000 {
rx-clock = "none";
tx-clock = "clk9";
phy-handle = <212000>;
+ phy-connection-type = "gmii";
pio-handle = <140001>;
};
- assignment : function number of the pin according to the Pin Assignment
tables in User Manual. Each pin can have up to 4 possible functions in
QE and two options for CPM.
- - has_irq : indicates if the pin is used as source of exteral
+ - has_irq : indicates if the pin is used as source of external
interrupts.
Example:
};
};
- g) Flash chip nodes
+ j) Flash chip nodes
Flash chips (Memory Technology Devices) are often used for solid state
file systems on embedded devices.