bluestar
Sat Feb 10 01:01:04 CST 2007
Dear Max:
I am very appreciated your information.
When on power-on, i found the sbp2port driver will send
"allocate address range" many times to ohci1394 to prepare
some memories for host controller to the purpose you mention.
And then host sends "AGENT_RESET",
"UNSOLICITED_STATUS_ENABLE", "ORB_POINTER" to
the device. At last, if the host want to do read/write commands,
it will put "command_block_ORB to memory" and then send
AsyncWrite(DOORBELL) to the device.
Could you teach me how do i get this memory that it put
command_block_ORB ??? If i know the this memory, maybe
fetch the ORB information and modify its data for fixing debug
of our host controller. (split 32 page_tables(128K bytes) to
both 16 page_tables(64K, 64K) )
Alan
On 2=A4=EB8=A4=E9, =A4U=A4=C87=AE=C935=A4=C0, "Maxim S. Shatskih" <m...@sto=
ragecraft.com> wrote:
> Read the SBP-2 spec first to understand what goes on at the level you plu=
g your
> filter in.
>
> For instance, "allocate address range" means - adding the _target_
> functionality to the host machine, so the 1394 device can be a master and=
write
> to some MDL you have provided using a 1394 transaction. Callbacks will be
> called at such a write attempt.
>
> This is something like common buffer DMA or message-signaled interrupts, =
but
> for 1394 bus. There is no such facility in USB since USB is strictly
> host-to-target, while 1394 is not.
>
> Some 1394-based protocols use "allocate address range". For instance, AV/C
> protocol used to discover the inner topology of the miniDV camera and to
> control its tape mechanism uses the address range (camera is a master, co=
mputer
> is a slave) to indicate "tape operation done" events.
>
> But, for SBP-2 (which is "storage over1394" or "SCSI over1394") - the
> "allocate address range" feature can be not employed at all.
>
> Also the "allocate bandwidth/channel/resources" features. They are for is=
och
> traffic only, no isoch traffic for SBP-2.
>
> --
> Maxim Shatskih, Windows DDK MVP
> StorageCraft Corporation
> m...@storagecraft.com
http://www.storagecraft.com