1/* 2 * (C) Copyright 2001 3 * Denis Peter, MPL AG Switzerland 4 * 5 * See file CREDITS for list of people who contributed to this 6 * project. 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License as 10 * published by the Free Software Foundation; either version 2 of 11 * the License, or (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 21 * MA 02111-1307 USA 22 * 23 */ 24 25USB Support for PIP405 and MIP405 (UHCI) 26======================================== 27 28The USB support is implemented on the base of the UHCI Host 29controller. 30 31Currently supported are USB Hubs, USB Keyboards, USB Floppys, USB 32flash sticks and USB network adaptors. 33Tested with a TEAC Floppy TEAC FD-05PUB and Chicony KU-8933 Keyboard. 34 35How it works: 36------------- 37 38The USB (at least the USB UHCI) needs a frame list (4k), transfer 39descripor and queue headers which are all located in the main memory. 40The UHCI allocates every milisecond the PCI bus and reads the current 41frame pointer. This may cause to crash the OS during boot. So the USB 42_MUST_ be stopped during OS boot. This is the reason, why the USB is 43NOT automatically started during start-up. If someone needs the USB 44he has to start it and should therefore be aware that he had to stop 45it before booting the OS. 46 47For USB keyboards this can be done by a script which is automatically 48started after the U-Boot is up and running. To boot an OS with a an 49USB keyboard another script is necessary, which first disables the 50USB and then executes the boot command. If the boot command fails, 51the script can reenable the USB kbd. 52 53Common USB Commands: 54- usb start: 55- usb reset: (re)starts the USB. All USB devices will be 56 initialized and a device tree is build for them. 57- usb tree: shows all USB devices in a tree like display 58- usb info [dev]: shows all USB infos of the device dev, or of all 59 the devices 60- usb stop [f]: stops the USB. If f==1 the USB will also stop if 61 an USB keyboard is assigned as stdin. The stdin 62 is then switched to serial input. 63Storage USB Commands: 64- usb scan: scans the USB for storage devices.The USB must be 65 running for this command (usb start) 66- usb device [dev]: show or set current USB staorage device 67- usb part [dev]: print partition table of one or all USB storage 68 devices 69- usb read addr blk# cnt: 70 read `cnt' blocks starting at block `blk#'to 71 memory address `addr' 72- usbboot addr dev:part: 73 boot from USB device 74 75Config Switches: 76---------------- 77CONFIG_CMD_USB enables basic USB support and the usb command 78CONFIG_USB_UHCI defines the lowlevel part.A lowlevel part must be defined 79 if using CONFIG_CMD_USB 80CONFIG_USB_KEYBOARD enables the USB Keyboard 81CONFIG_USB_STORAGE enables the USB storage devices 82CONFIG_USB_HOST_ETHER enables USB ethernet adapter support 83 84 85USB Host Networking 86=================== 87 88If you have a supported USB Ethernet adapter you can use it in U-Boot 89to obtain an IP address and load a kernel from a network server. 90 91Note: USB Host Networking is not the same as making your board act as a USB 92client. In that case your board is pretending to be an Ethernet adapter 93and will appear as a network interface to an attached computer. In that 94case the connection is via a USB cable with the computer acting as the host. 95 96With USB Host Networking, your board is the USB host. It controls the 97Ethernet adapter to which it is directly connected and the connection to 98the outside world is your adapter's Ethernet cable. Your board becomes an 99independent network device, able to connect and perform network operations 100independently of your computer. 101 102 103Device support 104-------------- 105 106Currently supported devices are listed in the drivers according to 107their vendor and product IDs. You can check your device by connecting it 108to a Linux machine and typing 'lsusb'. The drivers are in 109drivers/usb/eth. 110 111For example this lsusb output line shows a device with Vendor ID 0x0x95 112and product ID 0x7720: 113 114Bus 002 Device 010: ID 0b95:7720 ASIX Electronics Corp. AX88772 115 116If you look at drivers/usb/eth/asix.c you will see this line within the 117supported device list, so we know this adapter is supported. 118 119 { 0x0b95, 0x7720 }, /* Trendnet TU2-ET100 V3.0R */ 120 121If your adapter is not listed there is a still a chance that it will 122work. Try looking up the manufacturer of the chip inside your adapter. 123or take the adapter apart and look for chip markings. Then add a line 124for your vendor/product ID into the table of the appropriate driver, 125build U-Boot and see if it works. If not then there might be differences 126between the chip in your adapter and the driver. You could try to get a 127datasheet for your device and add support for it to U-Boot. This is not 128particularly difficult - you only need to provide support for four basic 129functions: init, halt, send and recv. 130 131 132Enabling USB Host Networking 133---------------------------- 134 135The normal U-Boot commands are used with USB networking, but you must 136start USB first. For example: 137 138usb start 139setenv bootfile /tftpboot/uImage 140bootp 141 142 143To enable USB Host Ethernet in U-Boot, your platform must of course 144support USB with CONFIG_CMD_USB enabled and working. You will need to 145add some config settings to your board header file: 146 147#define CONFIG_USB_HOST_ETHER /* Enable USB Ethernet adapters */ 148#define CONFIG_USB_ETHER_ASIX /* Asix, or whatever driver(s) you want */ 149 150As with built-in networking, you will also want to enable some network 151commands, for example: 152 153#define CONFIG_CMD_NET 154#define CONFIG_NET_MULTI 155#define CONFIG_CMD_PING 156#define CONFIG_CMD_DHCP 157 158and some bootp options, which tell your board to obtain its subnet, 159gateway IP, host name and boot path from the bootp/dhcp server. These 160settings should start you off: 161 162#define CONFIG_BOOTP_SUBNETMASK 163#define CONFIG_BOOTP_GATEWAY 164#define CONFIG_BOOTP_HOSTNAME 165#define CONFIG_BOOTP_BOOTPATH 166 167You can also set the default IP address of your board and the server 168as well as the default file to load when a 'bootp' command is issued. 169All of these can be obtained from the bootp server if not set. 170 171#define CONFIG_IPADDR 10.0.0.2 (replace with your value) 172#define CONFIG_SERVERIP 10.0.0.1 (replace with your value) 173#define CONFIG_BOOTFILE uImage 174 175 176The 'usb start' command should identify the adapter something like this: 177 178CrOS> usb start 179(Re)start USB... 180USB EHCI 1.00 181scanning bus for devices... 3 USB Device(s) found 182 scanning bus for storage devices... 0 Storage Device(s) found 183 scanning bus for ethernet devices... 1 Ethernet Device(s) found 184CrOS> print ethact 185ethact=asx0 186 187You can see that it found an ethernet device and we can print out the 188device name (asx0 in this case). 189 190Then 'bootp' or 'dhcp' should use it to obtain an IP address from DHCP, 191perhaps something like this: 192 193CrOS> bootp 194Waiting for Ethernet connection... done. 195BOOTP broadcast 1 196BOOTP broadcast 2 197DHCP client bound to address 172.22.73.81 198Using asx0 device 199TFTP from server 172.22.72.144; our IP address is 172.22.73.81 200Filename '/tftpboot/uImage-sjg-seaboard-261347'. 201Load address: 0x40c000 202Loading: ################################################################# 203 ################################################################# 204 ################################################################# 205 ################################################ 206done 207Bytes transferred = 3557464 (364858 hex) 208CrOS> 209 210 211Another way of doing this is to issue a tftp command, which will cause the 212bootp to happen automatically. 213 214 215MAC Addresses 216------------- 217 218Most Ethernet dongles have a built-in MAC address which is unique in the 219world. This is important so that devices on the network can be 220distinguised from each other. MAC address conflicts are evil and 221generally result in strange and eratic behaviour. 222 223Some boards have USB Ethernet chips on-board, and these sometimes do not 224have an assigned MAC address. In this case it is up to you to assign 225one which is unique. You should obtain a valid MAC address from a range 226assigned to you before you ship the product. 227 228Built-in Ethernet adapters support setting the MAC address by means of 229an ethaddr environment variable for each interface (ethaddr, eth1addr, 230eth2addr). There is similar support on the USB network side, using the 231names usbethaddr, usbeth1addr, etc. They are kept separate since we 232don't want a USB device taking the MAC address of a built-in device or 233vice versa. 234 235So if your USB Ethernet chip doesn't have a MAC address available then 236you must set usbethaddr to a suitable MAC address. At the time of 237writing this functionality is only supported by the SMSC driver. 238