1RapidIO subsystem mport driver for IDT Tsi721 PCI Express-to-SRIO bridge.
2=========================================================================
3
4I. Overview
5
6This driver implements all currently defined RapidIO mport callback functions.
7It supports maintenance read and write operations, inbound and outbound RapidIO
8doorbells, inbound maintenance port-writes and RapidIO messaging.
9
10To generate SRIO maintenance transactions this driver uses one of Tsi721 DMA
11channels. This mechanism provides access to larger range of hop counts and
12destination IDs without need for changes in outbound window translation.
13
14RapidIO messaging support uses dedicated messaging channels for each mailbox.
15For inbound messages this driver uses destination ID matching to forward messages
16into the corresponding message queue. Messaging callbacks are implemented to be
17fully compatible with RIONET driver (Ethernet over RapidIO messaging services).
18
19II. Known problems
20
21  None.
22
23III. DMA Engine Support
24
25Tsi721 mport driver supports DMA data transfers between local system memory and
26remote RapidIO devices. This functionality is implemented according to SLAVE
27mode API defined by common Linux kernel DMA Engine framework.
28
29Depending on system requirements RapidIO DMA operations can be included/excluded
30by setting CONFIG_RAPIDIO_DMA_ENGINE option. Tsi721 miniport driver uses seven
31out of eight available BDMA channels to support DMA data transfers.
32One BDMA channel is reserved for generation of maintenance read/write requests.
33
34If Tsi721 mport driver have been built with RAPIDIO_DMA_ENGINE support included,
35this driver will accept DMA-specific module parameter:
36  "dma_desc_per_channel" - defines number of hardware buffer descriptors used by
37                           each BDMA channel of Tsi721 (by default - 128).
38
39IV. Version History
40
41  1.1.0 - DMA operations re-worked to support data scatter/gather lists larger
42          than hardware buffer descriptors ring.
43  1.0.0 - Initial driver release.
44
45V.  License
46-----------------------------------------------
47
48  Copyright(c) 2011 Integrated Device Technology, Inc. All rights reserved.
49
50  This program is free software; you can redistribute it and/or modify it
51  under the terms of the GNU General Public License as published by the Free
52  Software Foundation; either version 2 of the License, or (at your option)
53  any later version.
54
55  This program is distributed in the hope that it will be useful, but WITHOUT
56  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
57  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
58  more details.
59
60  You should have received a copy of the GNU General Public License along with
61  this program; if not, write to the Free Software Foundation, Inc.,
62  59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
63