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-rw-r--r--Documentation/powerpc/booting-without-of.txt367
1 files changed, 314 insertions, 53 deletions
diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
index e9a3cb1d6b0..b5e46efeba8 100644
--- a/Documentation/powerpc/booting-without-of.txt
+++ b/Documentation/powerpc/booting-without-of.txt
@@ -52,7 +52,11 @@ Table of Contents
i) Freescale QUICC Engine module (QE)
j) CFI or JEDEC memory-mapped NOR flash
k) Global Utilities Block
- l) Xilinx IP cores
+ l) Freescale Communications Processor Module
+ m) Chipselect/Local Bus
+ n) 4xx/Axon EMAC ethernet nodes
+ o) Xilinx IP cores
+ p) Freescale Synchronous Serial Interface
VII - Specifying interrupt information for devices
1) interrupts property
@@ -671,10 +675,10 @@ device or bus to be described by the device tree.
In general, the format of an address for a device is defined by the
parent bus type, based on the #address-cells and #size-cells
-property. In the absence of such a property, the parent's parent
-values are used, etc... The kernel requires the root node to have
-those properties defining addresses format for devices directly mapped
-on the processor bus.
+properties. Note that the parent's parent definitions of #address-cells
+and #size-cells are not inhereted so every node with children must specify
+them. The kernel requires the root node to have those properties defining
+addresses format for devices directly mapped on the processor bus.
Those 2 properties define 'cells' for representing an address and a
size. A "cell" is a 32-bit number. For example, if both contain 2
@@ -711,13 +715,14 @@ define a bus type with a more complex address format, including things
like address space bits, you'll have to add a bus translator to the
prom_parse.c file of the recent kernels for your bus type.
-The "reg" property only defines addresses and sizes (if #size-cells
-is non-0) within a given bus. In order to translate addresses upward
+The "reg" property only defines addresses and sizes (if #size-cells is
+non-0) within a given bus. In order to translate addresses upward
(that is into parent bus addresses, and possibly into CPU physical
addresses), all busses must contain a "ranges" property. If the
"ranges" property is missing at a given level, it's assumed that
-translation isn't possible. The format of the "ranges" property for a
-bus is a list of:
+translation isn't possible, i.e., the registers are not visible on the
+parent bus. The format of the "ranges" property for a bus is a list
+of:
bus address, parent bus address, size
@@ -735,6 +740,10 @@ fit in a single 32-bit word. New 32-bit powerpc boards should use a
1/1 format, unless the processor supports physical addresses greater
than 32-bits, in which case a 2/1 format is recommended.
+Alternatively, the "ranges" property may be empty, indicating that the
+registers are visible on the parent bus using an identity mapping
+translation. In other words, the parent bus address space is the same
+as the child bus address space.
2) Note about "compatible" properties
-------------------------------------
@@ -1218,16 +1227,14 @@ platforms are moved over to use the flattened-device-tree model.
Required properties:
- reg : Offset and length of the register set for the device
- - device_type : Should be "mdio"
- compatible : Should define the compatible device type for the
- mdio. Currently, this is most likely to be "gianfar"
+ mdio. Currently, this is most likely to be "fsl,gianfar-mdio"
Example:
mdio@24520 {
reg = <24520 20>;
- device_type = "mdio";
- compatible = "gianfar";
+ compatible = "fsl,gianfar-mdio";
ethernet-phy@0 {
......
@@ -1254,6 +1261,10 @@ platforms are moved over to use the flattened-device-tree model.
services interrupts for this device.
- phy-handle : The phandle for the PHY connected to this ethernet
controller.
+ - fixed-link : <a b c d e> where a is emulated phy id - choose any,
+ but unique to the all specified fixed-links, b is duplex - 0 half,
+ 1 full, c is link speed - d#10/d#100/d#1000, d is pause - 0 no
+ pause, 1 pause, e is asym_pause - 0 no asym_pause, 1 asym_pause.
Recommended properties:
@@ -1408,7 +1419,6 @@ platforms are moved over to use the flattened-device-tree model.
Example multi port host USB controller device node :
usb@22000 {
- device_type = "usb";
compatible = "fsl-usb2-mph";
reg = <22000 1000>;
#address-cells = <1>;
@@ -1422,7 +1432,6 @@ platforms are moved over to use the flattened-device-tree model.
Example dual role USB controller device node :
usb@23000 {
- device_type = "usb";
compatible = "fsl-usb2-dr";
reg = <23000 1000>;
#address-cells = <1>;
@@ -1534,7 +1543,7 @@ platforms are moved over to use the flattened-device-tree model.
i) Root QE device
Required properties:
- - device_type : should be "qe";
+ - compatible : should be "fsl,qe";
- model : precise model of the QE, Can be "QE", "CPM", or "CPM2"
- reg : offset and length of the device registers.
- bus-frequency : the clock frequency for QUICC Engine.
@@ -1548,8 +1557,7 @@ platforms are moved over to use the flattened-device-tree model.
#address-cells = <1>;
#size-cells = <1>;
#interrupt-cells = <2>;
- device_type = "qe";
- model = "QE";
+ compatible = "fsl,qe";
ranges = <0 e0100000 00100000>;
reg = <e0100000 480>;
brg-frequency = <0>;
@@ -1560,8 +1568,8 @@ platforms are moved over to use the flattened-device-tree model.
ii) SPI (Serial Peripheral Interface)
Required properties:
- - device_type : should be "spi".
- - compatible : should be "fsl_spi".
+ - cell-index : SPI controller index.
+ - compatible : should be "fsl,spi".
- mode : the SPI operation mode, it can be "cpu" or "cpu-qe".
- reg : Offset and length of the register set for the device
- interrupts : <a b> where a is the interrupt number and b is a
@@ -1574,8 +1582,8 @@ platforms are moved over to use the flattened-device-tree model.
Example:
spi@4c0 {
- device_type = "spi";
- compatible = "fsl_spi";
+ cell-index = <0>;
+ compatible = "fsl,spi";
reg = <4c0 40>;
interrupts = <82 0>;
interrupt-parent = <700>;
@@ -1586,7 +1594,6 @@ platforms are moved over to use the flattened-device-tree model.
iii) USB (Universal Serial Bus Controller)
Required properties:
- - device_type : should be "usb".
- compatible : could be "qe_udc" or "fhci-hcd".
- mode : the could be "host" or "slave".
- reg : Offset and length of the register set for the device
@@ -1600,7 +1607,6 @@ platforms are moved over to use the flattened-device-tree model.
Example(slave):
usb@6c0 {
- device_type = "usb";
compatible = "qe_udc";
reg = <6c0 40>;
interrupts = <8b 0>;
@@ -1613,7 +1619,7 @@ platforms are moved over to use the flattened-device-tree model.
Required properties:
- device_type : should be "network", "hldc", "uart", "transparent"
- "bisync" or "atm".
+ "bisync", "atm", or "serial".
- compatible : could be "ucc_geth" or "fsl_atm" and so on.
- model : should be "UCC".
- device-id : the ucc number(1-8), corresponding to UCCx in UM.
@@ -1626,6 +1632,26 @@ platforms are moved over to use the flattened-device-tree model.
- interrupt-parent : the phandle for the interrupt controller that
services interrupts for this device.
- pio-handle : The phandle for the Parallel I/O port configuration.
+ - port-number : for UART drivers, the port number to use, between 0 and 3.
+ This usually corresponds to the /dev/ttyQE device, e.g. <0> = /dev/ttyQE0.
+ The port number is added to the minor number of the device. Unlike the
+ CPM UART driver, the port-number is required for the QE UART driver.
+ - soft-uart : for UART drivers, if specified this means the QE UART device
+ driver should use "Soft-UART" mode, which is needed on some SOCs that have
+ broken UART hardware. Soft-UART is provided via a microcode upload.
+ - rx-clock-name: the UCC receive clock source
+ "none": clock source is disabled
+ "brg1" through "brg16": clock source is BRG1-BRG16, respectively
+ "clk1" through "clk24": clock source is CLK1-CLK24, respectively
+ - tx-clock-name: the UCC transmit clock source
+ "none": clock source is disabled
+ "brg1" through "brg16": clock source is BRG1-BRG16, respectively
+ "clk1" through "clk24": clock source is CLK1-CLK24, respectively
+ The following two properties are deprecated. rx-clock has been replaced
+ with rx-clock-name, and tx-clock has been replaced with tx-clock-name.
+ Drivers that currently use the deprecated properties should continue to
+ do so, in order to support older device trees, but they should be updated
+ to check for the new properties first.
- rx-clock : represents the UCC receive clock source.
0x00 : clock source is disabled;
0x1~0x10 : clock source is BRG1~BRG16 respectively;
@@ -1754,7 +1780,7 @@ platforms are moved over to use the flattened-device-tree model.
vii) Multi-User RAM (MURAM)
Required properties:
- - device_type : should be "muram".
+ - compatible : should be "fsl,qe-muram", "fsl,cpm-muram".
- mode : the could be "host" or "slave".
- ranges : Should be defined as specified in 1) to describe the
translation of MURAM addresses.
@@ -1764,14 +1790,42 @@ platforms are moved over to use the flattened-device-tree model.
Example:
muram@10000 {
- device_type = "muram";
+ compatible = "fsl,qe-muram", "fsl,cpm-muram";
ranges = <0 00010000 0000c000>;
data-only@0{
+ compatible = "fsl,qe-muram-data",
+ "fsl,cpm-muram-data";
reg = <0 c000>;
};
};
+ viii) Uploaded QE firmware
+
+ If a new firwmare has been uploaded to the QE (usually by the
+ boot loader), then a 'firmware' child node should be added to the QE
+ node. This node provides information on the uploaded firmware that
+ device drivers may need.
+
+ Required properties:
+ - id: The string name of the firmware. This is taken from the 'id'
+ member of the qe_firmware structure of the uploaded firmware.
+ Device drivers can search this string to determine if the
+ firmware they want is already present.
+ - extended-modes: The Extended Modes bitfield, taken from the
+ firmware binary. It is a 64-bit number represented
+ as an array of two 32-bit numbers.
+ - virtual-traps: The virtual traps, taken from the firmware binary.
+ It is an array of 8 32-bit numbers.
+
+ Example:
+
+ firmware {
+ id = "Soft-UART";
+ extended-modes = <0 0>;
+ virtual-traps = <0 0 0 0 0 0 0 0>;
+ }
+
j) CFI or JEDEC memory-mapped NOR flash
Flash chips (Memory Technology Devices) are often used for solid state
@@ -2075,8 +2129,7 @@ platforms are moved over to use the flattened-device-tree model.
Example:
localbus@f0010100 {
- compatible = "fsl,mpc8272ads-localbus",
- "fsl,mpc8272-localbus",
+ compatible = "fsl,mpc8272-localbus",
"fsl,pq2-localbus";
#address-cells = <2>;
#size-cells = <1>;
@@ -2254,7 +2307,7 @@ platforms are moved over to use the flattened-device-tree model.
available.
For Axon: 0x0000012a
- l) Xilinx IP cores
+ o) Xilinx IP cores
The Xilinx EDK toolchain ships with a set of IP cores (devices) for use
in Xilinx Spartan and Virtex FPGAs. The devices cover the whole range
@@ -2276,7 +2329,7 @@ platforms are moved over to use the flattened-device-tree model.
properties of the device node. In general, device nodes for IP-cores
will take the following form:
- (name)@(base-address) {
+ (name): (generic-name)@(base-address) {
compatible = "xlnx,(ip-core-name)-(HW_VER)"
[, (list of compatible devices), ...];
reg = <(baseaddr) (size)>;
@@ -2286,6 +2339,9 @@ platforms are moved over to use the flattened-device-tree model.
xlnx,(parameter2) = <(int-value)>;
};
+ (generic-name): an open firmware-style name that describes the
+ generic class of device. Preferably, this is one word, such
+ as 'serial' or 'ethernet'.
(ip-core-name): the name of the ip block (given after the BEGIN
directive in system.mhs). Should be in lowercase
and all underscores '_' converted to dashes '-'.
@@ -2294,9 +2350,9 @@ platforms are moved over to use the flattened-device-tree model.
dropped from the parameter name, the name is converted
to lowercase and all underscore '_' characters are
converted to dashes '-'.
- (baseaddr): the C_BASEADDR parameter.
+ (baseaddr): the baseaddr parameter value (often named C_BASEADDR).
(HW_VER): from the HW_VER parameter.
- (size): equals C_HIGHADDR - C_BASEADDR + 1
+ (size): the address range size (often C_HIGHADDR - C_BASEADDR + 1).
Typically, the compatible list will include the exact IP core version
followed by an older IP core version which implements the same
@@ -2326,11 +2382,11 @@ platforms are moved over to use the flattened-device-tree model.
becomes the following device tree node:
- opb-uartlite-0@ec100000 {
+ opb_uartlite_0: serial@ec100000 {
device_type = "serial";
compatible = "xlnx,opb-uartlite-1.00.b";
reg = <ec100000 10000>;
- interrupt-parent = <&opb-intc>;
+ interrupt-parent = <&opb_intc_0>;
interrupts = <1 0>; // got this from the opb_intc parameters
current-speed = <d#115200>; // standard serial device prop
clock-frequency = <d#50000000>; // standard serial device prop
@@ -2339,16 +2395,19 @@ platforms are moved over to use the flattened-device-tree model.
xlnx,use-parity = <0>;
};
- Some IP cores actually implement 2 or more logical devices. In this case,
- the device should still describe the whole IP core with a single node
- and add a child node for each logical device. The ranges property can
- be used to translate from parent IP-core to the registers of each device.
- (Note: this makes the assumption that both logical devices have the same
- bus binding. If this is not true, then separate nodes should be used for
- each logical device). The 'cell-index' property can be used to enumerate
- logical devices within an IP core. For example, the following is the
- system.mhs entry for the dual ps2 controller found on the ml403 reference
- design.
+ Some IP cores actually implement 2 or more logical devices. In
+ this case, the device should still describe the whole IP core with
+ a single node and add a child node for each logical device. The
+ ranges property can be used to translate from parent IP-core to the
+ registers of each device. In addition, the parent node should be
+ compatible with the bus type 'xlnx,compound', and should contain
+ #address-cells and #size-cells, as with any other bus. (Note: this
+ makes the assumption that both logical devices have the same bus
+ binding. If this is not true, then separate nodes should be used
+ for each logical device). The 'cell-index' property can be used to
+ enumerate logical devices within an IP core. For example, the
+ following is the system.mhs entry for the dual ps2 controller found
+ on the ml403 reference design.
BEGIN opb_ps2_dual_ref
PARAMETER INSTANCE = opb_ps2_dual_ref_0
@@ -2370,21 +2429,24 @@ platforms are moved over to use the flattened-device-tree model.
It would result in the following device tree nodes:
- opb_ps2_dual_ref_0@a9000000 {
+ opb_ps2_dual_ref_0: opb-ps2-dual-ref@a9000000 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "xlnx,compound";
ranges = <0 a9000000 2000>;
// If this device had extra parameters, then they would
// go here.
ps2@0 {
compatible = "xlnx,opb-ps2-dual-ref-1.00.a";
reg = <0 40>;
- interrupt-parent = <&opb-intc>;
+ interrupt-parent = <&opb_intc_0>;
interrupts = <3 0>;
cell-index = <0>;
};
ps2@1000 {
compatible = "xlnx,opb-ps2-dual-ref-1.00.a";
reg = <1000 40>;
- interrupt-parent = <&opb-intc>;
+ interrupt-parent = <&opb_intc_0>;
interrupts = <3 0>;
cell-index = <0>;
};
@@ -2447,17 +2509,18 @@ platforms are moved over to use the flattened-device-tree model.
Gives this device tree (some properties removed for clarity):
- plb-v34-0 {
+ plb@0 {
#address-cells = <1>;
#size-cells = <1>;
+ compatible = "xlnx,plb-v34-1.02.a";
device_type = "ibm,plb";
ranges; // 1:1 translation
- plb-bram-if-cntrl-0@ffff0000 {
+ plb_bram_if_cntrl_0: bram@ffff0000 {
reg = <ffff0000 10000>;
}
- opb-v20-0 {
+ opb@20000000 {
#address-cells = <1>;
#size-cells = <1>;
ranges = <20000000 20000000 20000000
@@ -2465,11 +2528,11 @@ platforms are moved over to use the flattened-device-tree model.
80000000 80000000 40000000
c0000000 c0000000 20000000>;
- opb-uart16550-0@a0000000 {
+ opb_uart16550_0: serial@a0000000 {
reg = <a00000000 2000>;
};
- opb-intc-0@d1000fc0 {
+ opb_intc_0: interrupt-controller@d1000fc0 {
reg = <d1000fc0 20>;
};
};
@@ -2514,6 +2577,204 @@ platforms are moved over to use the flattened-device-tree model.
Requred properties:
- current-speed : Baud rate of uartlite
+ p) Freescale Synchronous Serial Interface
+
+ The SSI is a serial device that communicates with audio codecs. It can
+ be programmed in AC97, I2S, left-justified, or right-justified modes.
+
+ Required properties:
+ - compatible : compatible list, containing "fsl,ssi"
+ - cell-index : the SSI, <0> = SSI1, <1> = SSI2, and so on
+ - reg : offset and length of the register set for the device
+ - interrupts : <a b> where a is the interrupt number and b is a
+ field that represents an encoding of the sense and
+ level information for the interrupt. This should be
+ encoded based on the information in section 2)
+ depending on the type of interrupt controller you
+ have.
+ - interrupt-parent : the phandle for the interrupt controller that
+ services interrupts for this device.
+ - fsl,mode : the operating mode for the SSI interface
+ "i2s-slave" - I2S mode, SSI is clock slave
+ "i2s-master" - I2S mode, SSI is clock master
+ "lj-slave" - left-justified mode, SSI is clock slave
+ "lj-master" - l.j. mode, SSI is clock master
+ "rj-slave" - right-justified mode, SSI is clock slave
+ "rj-master" - r.j., SSI is clock master
+ "ac97-slave" - AC97 mode, SSI is clock slave
+ "ac97-master" - AC97 mode, SSI is clock master
+
+ Optional properties:
+ - codec-handle : phandle to a 'codec' node that defines an audio
+ codec connected to this SSI. This node is typically
+ a child of an I2C or other control node.
+
+ Child 'codec' node required properties:
+ - compatible : compatible list, contains the name of the codec
+
+ Child 'codec' node optional properties:
+ - clock-frequency : The frequency of the input clock, which typically
+ comes from an on-board dedicated oscillator.
+
+ * Freescale 83xx DMA Controller
+
+ Freescale PowerPC 83xx have on chip general purpose DMA controllers.
+
+ Required properties:
+
+ - compatible : compatible list, contains 2 entries, first is
+ "fsl,CHIP-dma", where CHIP is the processor
+ (mpc8349, mpc8360, etc.) and the second is
+ "fsl,elo-dma"
+ - reg : <registers mapping for DMA general status reg>
+ - ranges : Should be defined as specified in 1) to describe the
+ DMA controller channels.
+ - cell-index : controller index. 0 for controller @ 0x8100
+ - interrupts : <interrupt mapping for DMA IRQ>
+ - interrupt-parent : optional, if needed for interrupt mapping
+
+
+ - DMA channel nodes:
+ - compatible : compatible list, contains 2 entries, first is
+ "fsl,CHIP-dma-channel", where CHIP is the processor
+ (mpc8349, mpc8350, etc.) and the second is
+ "fsl,elo-dma-channel"
+ - reg : <registers mapping for channel>
+ - cell-index : dma channel index starts at 0.
+
+ Optional properties:
+ - interrupts : <interrupt mapping for DMA channel IRQ>
+ (on 83xx this is expected to be identical to
+ the interrupts property of the parent node)
+ - interrupt-parent : optional, if needed for interrupt mapping
+
+ Example:
+ dma@82a8 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "fsl,mpc8349-dma", "fsl,elo-dma";
+ reg = <82a8 4>;
+ ranges = <0 8100 1a4>;
+ interrupt-parent = <&ipic>;
+ interrupts = <47 8>;
+ cell-index = <0>;
+ dma-channel@0 {
+ compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
+ cell-index = <0>;
+ reg = <0 80>;
+ };
+ dma-channel@80 {
+ compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
+ cell-index = <1>;
+ reg = <80 80>;
+ };
+ dma-channel@100 {
+ compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
+ cell-index = <2>;
+ reg = <100 80>;
+ };
+ dma-channel@180 {
+ compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
+ cell-index = <3>;
+ reg = <180 80>;
+ };
+ };
+
+ * Freescale 85xx/86xx DMA Controller
+
+ Freescale PowerPC 85xx/86xx have on chip general purpose DMA controllers.
+
+ Required properties:
+
+ - compatible : compatible list, contains 2 entries, first is
+ "fsl,CHIP-dma", where CHIP is the processor
+ (mpc8540, mpc8540, etc.) and the second is
+ "fsl,eloplus-dma"
+ - reg : <registers mapping for DMA general status reg>
+ - cell-index : controller index. 0 for controller @ 0x21000,
+ 1 for controller @ 0xc000
+ - ranges : Should be defined as specified in 1) to describe the
+ DMA controller channels.
+
+ - DMA channel nodes:
+ - compatible : compatible list, contains 2 entries, first is
+ "fsl,CHIP-dma-channel", where CHIP is the processor
+ (mpc8540, mpc8560, etc.) and the second is
+ "fsl,eloplus-dma-channel"
+ - cell-index : dma channel index starts at 0.
+ - reg : <registers mapping for channel>
+ - interrupts : <interrupt mapping for DMA channel IRQ>
+ - interrupt-parent : optional, if needed for interrupt mapping
+
+ Example:
+ dma@21300 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "fsl,mpc8540-dma", "fsl,eloplus-dma";
+ reg = <21300 4>;
+ ranges = <0 21100 200>;
+ cell-index = <0>;
+ dma-channel@0 {
+ compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel";
+ reg = <0 80>;
+ cell-index = <0>;
+ interrupt-parent = <&mpic>;
+ interrupts = <14 2>;
+ };
+ dma-channel@80 {
+ compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel";
+ reg = <80 80>;
+ cell-index = <1>;
+ interrupt-parent = <&mpic>;
+ interrupts = <15 2>;
+ };
+ dma-channel@100 {
+ compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel";
+ reg = <100 80>;
+ cell-index = <2>;
+ interrupt-parent = <&mpic>;
+ interrupts = <16 2>;
+ };
+ dma-channel@180 {
+ compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel";
+ reg = <180 80>;
+ cell-index = <3>;
+ interrupt-parent = <&mpic>;
+ interrupts = <17 2>;
+ };
+ };
+
+ * Freescale 8xxx/3.0 Gb/s SATA nodes
+
+ SATA nodes are defined to describe on-chip Serial ATA controllers.
+ Each SATA port should have its own node.
+
+ Required properties:
+ - compatible : compatible list, contains 2 entries, first is
+ "fsl,CHIP-sata", where CHIP is the processor
+ (mpc8315, mpc8379, etc.) and the second is
+ "fsl,pq-sata"
+ - interrupts : <interrupt mapping for SATA IRQ>
+ - cell-index : controller index.
+ 1 for controller @ 0x18000
+ 2 for controller @ 0x19000
+ 3 for controller @ 0x1a000
+ 4 for controller @ 0x1b000
+
+ Optional properties:
+ - interrupt-parent : optional, if needed for interrupt mapping
+ - reg : <registers mapping>
+
+ Example:
+
+ sata@18000 {
+ compatible = "fsl,mpc8379-sata", "fsl,pq-sata";
+ reg = <0x18000 0x1000>;
+ cell-index = <1>;
+ interrupts = <2c 8>;
+ interrupt-parent = < &ipic >;
+ };
+
More devices will be defined as this spec matures.
VII - Specifying interrupt information for devices