[U-Boot-Users] reg ISP 1561 integration with u-boot1.1.6

Wolfgang Denk wd at denx.de
Thu Jan 11 14:13:21 CET 2007

In message <200701110950.08710.matthias.fuchs at esd-electronics.com> you wrote:
> These are different issues! usb_ohci.c uses readl and writel to access the 
> controller's registers from the CPU (e.g. ohci.regs). The original code never
> swaps here. But a PCI OHCI controller on a PowerPC needs it. The mXX_swap
> macros are used to swap data fields in structures that are passed to the host
> controller indirectly.

Be careful! Keep in mind that you may need both cases in one system,
like using a PCI OHCI controller on a MPC5200 board where you have to
support USB both on the internal USB controllers and on the PCI card.

See our linuxppc_2_4_devel tree for one possible implementation.

Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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