On Tue, 5 Dec 2006 11:19:38 +0900
Kouya SHIMURA <kouya@jp.fujitsu.com> wrote:
> Hi, Tristan
>
> Thanks for your comments.
>
> * In any case, I have to allocate another page for IDE PIO buffer.
> Actually this patch works well on any size of buffer. The size is
> just trade-off with the performance. FYI, 2048 bytes seems to be
> enough for CDROM.
You want a bit more if you ever begin to support multimedia or READ/WRITE
LONG, that can get you up to about 2500 bytes per "sector".
You also need to watch that you handle inb/inw/inl on the data port
properly as devices can support 32bit I/O on the data port which is not
the same as a 32bit I/O usually is (it does not return the value of port,
port +1, port + 2, port +3). Or you can report that 32bit I/O is not
supported in the drive identify page..
Alan
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel
Kouya SHIMURA <kouya@jp.fujitsu.com> wrote:
> Hi, Tristan
>
> Thanks for your comments.
>
> * In any case, I have to allocate another page for IDE PIO buffer.
> Actually this patch works well on any size of buffer. The size is
> just trade-off with the performance. FYI, 2048 bytes seems to be
> enough for CDROM.
You want a bit more if you ever begin to support multimedia or READ/WRITE
LONG, that can get you up to about 2500 bytes per "sector".
You also need to watch that you handle inb/inw/inl on the data port
properly as devices can support 32bit I/O on the data port which is not
the same as a 32bit I/O usually is (it does not return the value of port,
port +1, port + 2, port +3). Or you can report that 32bit I/O is not
supported in the drive identify page..
Alan
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel