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Diffstat (limited to 'qemu/roms/u-boot/doc/README.usb')
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diff --git a/qemu/roms/u-boot/doc/README.usb b/qemu/roms/u-boot/doc/README.usb deleted file mode 100644 index bc768a385..000000000 --- a/qemu/roms/u-boot/doc/README.usb +++ /dev/null @@ -1,228 +0,0 @@ -/* - * (C) Copyright 2001 - * Denis Peter, MPL AG Switzerland - * - * SPDX-License-Identifier: GPL-2.0+ - */ - -USB Support for PIP405 and MIP405 (UHCI) -======================================== - -The USB support is implemented on the base of the UHCI Host -controller. - -Currently supported are USB Hubs, USB Keyboards, USB Floppys, USB -flash sticks and USB network adaptors. -Tested with a TEAC Floppy TEAC FD-05PUB and Chicony KU-8933 Keyboard. - -How it works: -------------- - -The USB (at least the USB UHCI) needs a frame list (4k), transfer -descripor and queue headers which are all located in the main memory. -The UHCI allocates every milisecond the PCI bus and reads the current -frame pointer. This may cause to crash the OS during boot. So the USB -_MUST_ be stopped during OS boot. This is the reason, why the USB is -NOT automatically started during start-up. If someone needs the USB -he has to start it and should therefore be aware that he had to stop -it before booting the OS. - -For USB keyboards this can be done by a script which is automatically -started after the U-Boot is up and running. To boot an OS with a an -USB keyboard another script is necessary, which first disables the -USB and then executes the boot command. If the boot command fails, -the script can reenable the USB kbd. - -Common USB Commands: -- usb start: -- usb reset: (re)starts the USB. All USB devices will be - initialized and a device tree is build for them. -- usb tree: shows all USB devices in a tree like display -- usb info [dev]: shows all USB infos of the device dev, or of all - the devices -- usb stop [f]: stops the USB. If f==1 the USB will also stop if - an USB keyboard is assigned as stdin. The stdin - is then switched to serial input. -Storage USB Commands: -- usb scan: scans the USB for storage devices.The USB must be - running for this command (usb start) -- usb device [dev]: show or set current USB storage device -- usb part [dev]: print partition table of one or all USB storage - devices -- usb read addr blk# cnt: - read `cnt' blocks starting at block `blk#'to - memory address `addr' -- usbboot addr dev:part: - boot from USB device - -Config Switches: ----------------- -CONFIG_CMD_USB enables basic USB support and the usb command -CONFIG_USB_UHCI defines the lowlevel part.A lowlevel part must be defined - if using CONFIG_CMD_USB -CONFIG_USB_KEYBOARD enables the USB Keyboard -CONFIG_USB_STORAGE enables the USB storage devices -CONFIG_USB_HOST_ETHER enables USB ethernet adapter support - - -USB Host Networking -=================== - -If you have a supported USB Ethernet adapter you can use it in U-Boot -to obtain an IP address and load a kernel from a network server. - -Note: USB Host Networking is not the same as making your board act as a USB -client. In that case your board is pretending to be an Ethernet adapter -and will appear as a network interface to an attached computer. In that -case the connection is via a USB cable with the computer acting as the host. - -With USB Host Networking, your board is the USB host. It controls the -Ethernet adapter to which it is directly connected and the connection to -the outside world is your adapter's Ethernet cable. Your board becomes an -independent network device, able to connect and perform network operations -independently of your computer. - - -Device support --------------- - -Currently supported devices are listed in the drivers according to -their vendor and product IDs. You can check your device by connecting it -to a Linux machine and typing 'lsusb'. The drivers are in -drivers/usb/eth. - -For example this lsusb output line shows a device with Vendor ID 0x0x95 -and product ID 0x7720: - -Bus 002 Device 010: ID 0b95:7720 ASIX Electronics Corp. AX88772 - -If you look at drivers/usb/eth/asix.c you will see this line within the -supported device list, so we know this adapter is supported. - - { 0x0b95, 0x7720 }, /* Trendnet TU2-ET100 V3.0R */ - -If your adapter is not listed there is a still a chance that it will -work. Try looking up the manufacturer of the chip inside your adapter. -or take the adapter apart and look for chip markings. Then add a line -for your vendor/product ID into the table of the appropriate driver, -build U-Boot and see if it works. If not then there might be differences -between the chip in your adapter and the driver. You could try to get a -datasheet for your device and add support for it to U-Boot. This is not -particularly difficult - you only need to provide support for four basic -functions: init, halt, send and recv. - - -Enabling USB Host Networking ----------------------------- - -The normal U-Boot commands are used with USB networking, but you must -start USB first. For example: - -usb start -setenv bootfile /tftpboot/uImage -bootp - - -To enable USB Host Ethernet in U-Boot, your platform must of course -support USB with CONFIG_CMD_USB enabled and working. You will need to -add some config settings to your board header file: - -#define CONFIG_CMD_USB /* the 'usb' interactive command */ -#define CONFIG_USB_HOST_ETHER /* Enable USB Ethernet adapters */ - -and one or more of the following for individual adapter hardware: - -#define CONFIG_USB_ETHER_ASIX -#define CONFIG_USB_ETHER_MCS7830 -#define CONFIG_USB_ETHER_SMSC95XX - -As with built-in networking, you will also want to enable some network -commands, for example: - -#define CONFIG_CMD_NET -#define CONFIG_CMD_PING -#define CONFIG_CMD_DHCP - -and some bootp options, which tell your board to obtain its subnet, -gateway IP, host name and boot path from the bootp/dhcp server. These -settings should start you off: - -#define CONFIG_BOOTP_SUBNETMASK -#define CONFIG_BOOTP_GATEWAY -#define CONFIG_BOOTP_HOSTNAME -#define CONFIG_BOOTP_BOOTPATH - -You can also set the default IP address of your board and the server -as well as the default file to load when a 'bootp' command is issued. -However note that encoding these individual network settings into a -common exectuable is discouraged, as it leads to potential conflicts, -and all the parameters can either get stored in the board's external -environment, or get obtained from the bootp server if not set. - -#define CONFIG_IPADDR 10.0.0.2 (replace with your value) -#define CONFIG_SERVERIP 10.0.0.1 (replace with your value) -#define CONFIG_BOOTFILE "uImage" - - -The 'usb start' command should identify the adapter something like this: - -CrOS> usb start -(Re)start USB... -USB EHCI 1.00 -scanning bus for devices... 3 USB Device(s) found - scanning bus for storage devices... 0 Storage Device(s) found - scanning bus for ethernet devices... 1 Ethernet Device(s) found -CrOS> print ethact -ethact=asx0 - -You can see that it found an ethernet device and we can print out the -device name (asx0 in this case). - -Then 'bootp' or 'dhcp' should use it to obtain an IP address from DHCP, -perhaps something like this: - -CrOS> bootp -Waiting for Ethernet connection... done. -BOOTP broadcast 1 -BOOTP broadcast 2 -DHCP client bound to address 172.22.73.81 -Using asx0 device -TFTP from server 172.22.72.144; our IP address is 172.22.73.81 -Filename '/tftpboot/uImage-sjg-seaboard-261347'. -Load address: 0x40c000 -Loading: ################################################################# - ################################################################# - ################################################################# - ################################################ -done -Bytes transferred = 3557464 (364858 hex) -CrOS> - - -Another way of doing this is to issue a tftp command, which will cause the -bootp to happen automatically. - - -MAC Addresses -------------- - -Most Ethernet dongles have a built-in MAC address which is unique in the -world. This is important so that devices on the network can be -distinguised from each other. MAC address conflicts are evil and -generally result in strange and eratic behaviour. - -Some boards have USB Ethernet chips on-board, and these sometimes do not -have an assigned MAC address. In this case it is up to you to assign -one which is unique. You should obtain a valid MAC address from a range -assigned to you before you ship the product. - -Built-in Ethernet adapters support setting the MAC address by means of -an ethaddr environment variable for each interface (ethaddr, eth1addr, -eth2addr). There is similar support on the USB network side, using the -names usbethaddr, usbeth1addr, etc. They are kept separate since we -don't want a USB device taking the MAC address of a built-in device or -vice versa. - -So if your USB Ethernet chip doesn't have a MAC address available then -you must set usbethaddr to a suitable MAC address. At the time of -writing this functionality is only supported by the SMSC driver. |