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81 lines
3.1 KiB
Plaintext
81 lines
3.1 KiB
Plaintext
/*
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* (C) Copyright 2001
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* Denis Peter, MPL AG Switzerland
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*
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* See file CREDITS for list of people who contributed to this
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* project.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of
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* the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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* MA 02111-1307 USA
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*
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*/
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USB Support for PIP405 and MIP405 (UHCI)
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========================================
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The USB support is implemented on the base of the UHCI Host
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controller.
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Currently supported are USB Hubs, USB Keyboards and USB Floppys.
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Tested with a TEAC Floppy TEAC FD-05PUB and Chicony KU-8933 Keyboard.
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How it works:
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-------------
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The USB (at least the USB UHCI) needs a frame list (4k), transfer
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descripor and queue headers which are all located in the main memory.
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The UHCI allocates every milisecond the PCI bus and reads the current
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frame pointer. This may cause to crash the OS during boot. So the USB
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_MUST_ be stopped during OS boot. This is the reason, why the USB is
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NOT automatically started during start-up. If someone needs the USB
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he has to start it and should therefore be aware that he had to stop
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it before booting the OS.
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For USB keyboards this can be done by a script which is automatically
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started after the U-Boot is up and running. To boot an OS with a an
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USB keyboard another script is necessary, which first disables the
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USB and then executes the boot command. If the boot command fails,
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the script can reenable the USB kbd.
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Common USB Commands:
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- usb start:
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- usb reset: (re)starts the USB. All USB devices will be
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initialized and a device tree is build for them.
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- usb tree: shows all USB devices in a tree like display
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- usb info [dev]: shows all USB infos of the device dev, or of all
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the devices
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- usb stop [f]: stops the USB. If f==1 the USB will also stop if
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an USB keyboard is assigned as stdin. The stdin
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is then switched to serial input.
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Storage USB Commands:
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- usb scan: scans the USB for storage devices.The USB must be
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running for this command (usb start)
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- usb device [dev]: show or set current USB staorage device
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- usb part [dev]: print partition table of one or all USB storage
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devices
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- usb read addr blk# cnt:
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read `cnt' blocks starting at block `blk#'to
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memory address `addr'
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- usbboot addr dev:part:
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boot from USB device
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Config Switches:
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----------------
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CFG_CMD_USB enables basic USB support and the usb command
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CONFIG_USB_UHCI defines the lowlevel part.A lowlevel part must be defined if
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using CFG_CMD_USB
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CONFIG_USB_KEYBOARD enables the USB Keyboard
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CONFIG_USB_STORAGE enables the USB storage devices
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