[PATCH 3/4] Device tree bindings for Xilinx devices
Josh Boyer
jwboyer at linux.vnet.ibm.com
Tue Oct 23 22:36:01 EST 2007
On Mon, 22 Oct 2007 22:27:41 -0600
Grant Likely <grant.likely at secretlab.ca> wrote:
> From: Grant Likely <grant.likely at secretlab.ca>
>
> Signed-off-by: Grant Likely <grant.likely at secretlab.ca>
> Acked-by: Stephen Neuendorffer <stephen.neuendorffer at xilinx.com>
This looks pretty good to me.
Acked-by: Josh Boyer <jwboyer at linux.vnet.ibm.com>
josh
> ---
>
> Documentation/powerpc/booting-without-of.txt | 261 ++++++++++++++++++++++++++
> 1 files changed, 261 insertions(+), 0 deletions(-)
>
> diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
> index a96e853..59df69d 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 +2243,266 @@ 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 = "xlnx,(ip-core-name)-(HW_VER)"
> + [, (list of compatible devices), ...];
> + reg = <(baseaddr) (size)>;
> + interrupt-parent = <&interrupt-controller-phandle>;
> + interrupts = < ... >;
> + xlnx,(parameter1) = "(string-value)";
> + xlnx,(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 = "xlnx,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
> + xlnx,data-bits = <8>;
> + xlnx,odd-parity = <0>;
> + 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.
> +
> + 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 = "xlnx,opb-ps2-dual-ref-1.00.a";
> + reg = <0 40>;
> + interrupt-parent = <&opb-intc>;
> + interrupts = <3 0>;
> + cell-index = <0>;
> + };
> + ps2 at 1000 {
> + compatible = "xlnx,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.
> +
> + 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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