u-boot/doc/README.generic_usb_ohci
Heiko Schocher 064b55cfcb powerpc, 5xxx, 512x: remove support for mpc5xxx and mpc512x
There was for long time no activity in the mpx5xxx area.
We need to go further and convert to Kconfig, but it
turned out, nobody is interested anymore in mpc5xxx,
so remove it.

Signed-off-by: Heiko Schocher <hs@denx.de>
2017-06-16 10:14:55 -04:00

63 lines
1.6 KiB
Text

Notes on the the generic USB-OHCI driver
========================================
This driver (drivers/usb/usb_ohci.[ch]) is the result of the merge of
various existing OHCI drivers that were basically identical beside
cpu/board dependant initalization. This initalization has been moved
into cpu/board directories and are called via the hooks below.
Configuration options
----------------------
CONFIG_USB_OHCI_NEW: enable the new OHCI driver
CONFIG_SYS_USB_OHCI_BOARD_INIT: call the board dependant hooks:
- extern int usb_board_init(void);
- extern int usb_board_stop(void);
- extern int usb_cpu_init_fail(void);
CONFIG_SYS_USB_OHCI_CPU_INIT: call the cpu dependant hooks:
- extern int usb_cpu_init(void);
- extern int usb_cpu_stop(void);
- extern int usb_cpu_init_fail(void);
CONFIG_SYS_USB_OHCI_REGS_BASE: defines the base address of the OHCI
registers
CONFIG_SYS_USB_OHCI_SLOT_NAME: slot name
CONFIG_SYS_USB_OHCI_MAX_ROOT_PORTS: maximal number of ports of the
root hub.
Endianness issues
------------------
The USB bus operates in little endian, but unfortunately there are
OHCI controllers that operate in big endian such as ppc4xx. For these the
config option
CONFIG_SYS_OHCI_BE_CONTROLLER
needs to be defined.
PCI Controllers
----------------
You'll need to define
CONFIG_PCI_OHCI
If you have several USB PCI controllers, define
CONFIG_PCI_OHCI_DEVNO: number of the OHCI device in PCI list
If undefined, the first instance found in PCI space will be used.
PCI Controllers need to do byte swapping on register accesses, so they
should to define:
CONFIG_SYS_OHCI_SWAP_REG_ACCESS