[PATCH v3] Device tree bindings for Xilinx devices
Grant Likely
grant.likely at secretlab.ca
Fri Oct 19 03:22:59 EST 2007
From: Grant Likely <grant.likely at secretlab.ca>
Signed-off-by: Grant Likely <grant.likely at secretlab.ca>
---
Documentation/powerpc/booting-without-of.txt | 264 ++++++++++++++++++++++++++
1 files changed, 264 insertions(+), 0 deletions(-)
diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
index a96e853..d4dedf4 100644
--- a/Documentation/powerpc/booting-without-of.txt
+++ b/Documentation/powerpc/booting-without-of.txt
@@ -52,6 +52,7 @@ 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
VII - Specifying interrupt information for devices
1) interrupts property
@@ -2242,6 +2243,269 @@ platforms are moved over to use the flattened-device-tree model.
available.
For Axon: 0x0000012a
+ l) 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
+ of standard device types (network, serial, etc.) and miscellanious
+ devices (gpio, LCD, spi, etc). Also, since these devices are
+ implemented within the fpga fabric every instance of the device can be
+ synthesised with different options that change the behaviour.
+
+ Each IP-core has a set of parameters which the FPGA designer can use to
+ control how the core is synthesized. Historically, the EDK tool would
+ extract the device parameters relevant to device drivers and copy them
+ into an 'xparameters.h' in the form of #define symbols. This tells the
+ device drivers how the IP cores are configured, but it requres the kernel
+ to be recompiled every time the FPGA bitstream is resynthesized.
+
+ The new approach is to export the parameters into the device tree and
+ generate a new device tree each time the FPGA bitstream changes. The
+ parameters which used to be exported as #defines will now become
+ properties of the device node. In general, device nodes for IP-cores
+ will take the following form:
+
+ (name)@(base-address) {
+ compatible = "xilinx,(ip-core-name)-(HW_VER)"
+ [, (list of compatible devices), ...];
+ reg = <(baseaddr) (size)>;
+ interrupt-parent = <&interrupt-controller-phandle>;
+ interrupts = < ... >;
+ xilinx,(parameter1) = "(string-value)";
+ xilinx,(parameter2) = <(int-value)>;
+ };
+
+ (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 '-'.
+ (name): is derived from the "PARAMETER INSTANCE" value.
+ (parameter#): C_* parameters from system.mhs. The C_ prefix is
+ dropped from the parameter name, the name is converted
+ to lowercase and all underscore '_' characters are
+ converted to dashes '-'.
+ (baseaddr): the C_BASEADDR parameter.
+ (HW_VER): from the HW_VER parameter.
+ (size): equals 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
+ interface or any other device with the same interface.
+
+ 'reg', 'interrupt-parent' and 'interrupts' are all optional properties.
+
+ For example, the following block from system.mhs:
+
+ BEGIN opb_uartlite
+ PARAMETER INSTANCE = opb_uartlite_0
+ PARAMETER HW_VER = 1.00.b
+ PARAMETER C_BAUDRATE = 115200
+ PARAMETER C_DATA_BITS = 8
+ PARAMETER C_ODD_PARITY = 0
+ PARAMETER C_USE_PARITY = 0
+ PARAMETER C_CLK_FREQ = 50000000
+ PARAMETER C_BASEADDR = 0xEC100000
+ PARAMETER C_HIGHADDR = 0xEC10FFFF
+ BUS_INTERFACE SOPB = opb_7
+ PORT OPB_Clk = CLK_50MHz
+ PORT Interrupt = opb_uartlite_0_Interrupt
+ PORT RX = opb_uartlite_0_RX
+ PORT TX = opb_uartlite_0_TX
+ PORT OPB_Rst = sys_bus_reset_0
+ END
+
+ becomes the following device tree node:
+
+ opb-uartlite-0 at ec100000 {
+ device_type = "serial";
+ compatible = "xilinx,opb-uartlite-1.00.b";
+ reg = <ec100000 10000>;
+ interrupt-parent = <&opb-intc>;
+ 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
+ xilinx,data-bits = <8>;
+ xilinx,odd-parity = <0>;
+ xilinx,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.
+
+ BEGIN opb_ps2_dual_ref
+ PARAMETER INSTANCE = opb_ps2_dual_ref_0
+ PARAMETER HW_VER = 1.00.a
+ PARAMETER C_BASEADDR = 0xA9000000
+ PARAMETER C_HIGHADDR = 0xA9001FFF
+ BUS_INTERFACE SOPB = opb_v20_0
+ PORT Sys_Intr1 = ps2_1_intr
+ PORT Sys_Intr2 = ps2_2_intr
+ PORT Clkin1 = ps2_clk_rx_1
+ PORT Clkin2 = ps2_clk_rx_2
+ PORT Clkpd1 = ps2_clk_tx_1
+ PORT Clkpd2 = ps2_clk_tx_2
+ PORT Rx1 = ps2_d_rx_1
+ PORT Rx2 = ps2_d_rx_2
+ PORT Txpd1 = ps2_d_tx_1
+ PORT Txpd2 = ps2_d_tx_2
+ END
+
+ It would result in the following device tree nodes:
+
+ opb_ps2_dual_ref_0 at a9000000 {
+ ranges = <0 a9000000 2000>;
+ // If this device had extra parameters, then they would
+ // go here.
+ ps2 at 0 {
+ compatible = "xilinx,opb-ps2-dual-ref-1.00.a";
+ reg = <0 40>;
+ interrupt-parent = <&opb-intc>;
+ interrupts = <3 0>;
+ cell-index = <0>;
+ };
+ ps2 at 1000 {
+ compatible = "xilinx,opb-ps2-dual-ref-1.00.a";
+ reg = <1000 40>;
+ interrupt-parent = <&opb-intc>;
+ interrupts = <3 0>;
+ cell-index = <0>;
+ };
+ };
+
+ Also, the system.mhs file defines bus attachments from the processor
+ to the devices. The device tree structure should reflect the bus
+ attachments. Again an example; this system.mhs fragment:
+
+ BEGIN ppc405_virtex4
+ PARAMETER INSTANCE = ppc405_0
+ PARAMETER HW_VER = 1.01.a
+ BUS_INTERFACE DPLB = plb_v34_0
+ BUS_INTERFACE IPLB = plb_v34_0
+ END
+
+ BEGIN opb_intc
+ PARAMETER INSTANCE = opb_intc_0
+ PARAMETER HW_VER = 1.00.c
+ PARAMETER C_BASEADDR = 0xD1000FC0
+ PARAMETER C_HIGHADDR = 0xD1000FDF
+ BUS_INTERFACE SOPB = opb_v20_0
+ END
+
+ BEGIN opb_uart16550
+ PARAMETER INSTANCE = opb_uart16550_0
+ PARAMETER HW_VER = 1.00.d
+ PARAMETER C_BASEADDR = 0xa0000000
+ PARAMETER C_HIGHADDR = 0xa0001FFF
+ BUS_INTERFACE SOPB = opb_v20_0
+ END
+
+ BEGIN plb_v34
+ PARAMETER INSTANCE = plb_v34_0
+ PARAMETER HW_VER = 1.02.a
+ END
+
+ BEGIN plb_bram_if_cntlr
+ PARAMETER INSTANCE = plb_bram_if_cntlr_0
+ PARAMETER HW_VER = 1.00.b
+ PARAMETER C_BASEADDR = 0xFFFF0000
+ PARAMETER C_HIGHADDR = 0xFFFFFFFF
+ BUS_INTERFACE SPLB = plb_v34_0
+ END
+
+ BEGIN plb2opb_bridge
+ PARAMETER INSTANCE = plb2opb_bridge_0
+ PARAMETER HW_VER = 1.01.a
+ PARAMETER C_RNG0_BASEADDR = 0x20000000
+ PARAMETER C_RNG0_HIGHADDR = 0x3FFFFFFF
+ PARAMETER C_RNG1_BASEADDR = 0x60000000
+ PARAMETER C_RNG1_HIGHADDR = 0x7FFFFFFF
+ PARAMETER C_RNG2_BASEADDR = 0x80000000
+ PARAMETER C_RNG2_HIGHADDR = 0xBFFFFFFF
+ PARAMETER C_RNG3_BASEADDR = 0xC0000000
+ PARAMETER C_RNG3_HIGHADDR = 0xDFFFFFFF
+ BUS_INTERFACE SPLB = plb_v34_0
+ BUS_INTERFACE MOPB = opb_v20_0
+ END
+
+ Gives this device tree (some properties removed for clarity):
+
+ plb-v34-0 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ device_type = "ibm,plb";
+ ranges; // 1:1 translation
+
+ plb-bram-if-cntrl-0 at ffff0000 {
+ reg = <ffff0000 10000>;
+ }
+
+ opb-v20-0 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges = <20000000 20000000 20000000
+ 60000000 60000000 20000000
+ 80000000 80000000 40000000
+ c0000000 c0000000 20000000>;
+
+ opb-uart16550-0 at a0000000 {
+ reg = <a00000000 2000>;
+ };
+
+ opb-intc-0 at d1000fc0 {
+ reg = <d1000fc0 20>;
+ };
+ };
+ };
+
+ That covers the general approach to binding xilinx IP cores into the
+ device tree. The following are bindings for specific devices:
+
+ i) Xilinx ML300 Framebuffer
+
+ Simple framebuffer device from the ML300 reference design (also on the
+ ML403 reference design as well as others).
+
+ Optional properties:
+ - resolution : <xres yres> pixel resolution of framebuffer. Some
+ implementations use a different resolution. Default
+ is <d#640 d#480>
+ - virt-resolution : <xvirt yvirt> Size of framebuffer in memory.
+ Default is <d#1024 d#480>.
+ - rotate-display (empty) : rotate display 180 degrees.
+
+ ii) Xilinx SystemACE
+
+ The Xilinx SystemACE device is used to program FPGAs from an FPGA
+ bitstream stored on a CF card. It can also be used as a generic CF
+ interface device.
+
+ Required properties:
+ - compatible : Should include "xilinx,sysace" in the list
+
+ Optional properties:
+ - 8-bit (empty) : Set this property for SystemACE in 8 bit mode
+
+ iii) Xilinx EMAC and Xilinx TEMAC
+
+ Xilinx Ethernet devices. In addition to general xilinx properties
+ listed above, nodes for these devices should include a phy-handle
+ property, and may include other common network device properties
+ like local-mac-address.
+
+ iv) Xilinx Uartlite
+
+ Xilinx uartlite devices are simple fixed speed serial ports.
+
+ Requred properties:
+ - current-speed : Baud rate of uartlite
+
More devices will be defined as this spec matures.
VII - Specifying interrupt information for devices
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