| Alexandre Bounine | 48618fb | 2011-11-02 13:39:09 -0700 | [diff] [blame] | 1 | RapidIO subsystem mport driver for IDT Tsi721 PCI Express-to-SRIO bridge. |
| 2 | ========================================================================= |
| 3 | |
| 4 | I. Overview |
| 5 | |
| 6 | This driver implements all currently defined RapidIO mport callback functions. |
| 7 | It supports maintenance read and write operations, inbound and outbound RapidIO |
| 8 | doorbells, inbound maintenance port-writes and RapidIO messaging. |
| 9 | |
| 10 | To generate SRIO maintenance transactions this driver uses one of Tsi721 DMA |
| 11 | channels. This mechanism provides access to larger range of hop counts and |
| 12 | destination IDs without need for changes in outbound window translation. |
| 13 | |
| 14 | RapidIO messaging support uses dedicated messaging channels for each mailbox. |
| 15 | For inbound messages this driver uses destination ID matching to forward messages |
| 16 | into the corresponding message queue. Messaging callbacks are implemented to be |
| 17 | fully compatible with RIONET driver (Ethernet over RapidIO messaging services). |
| 18 | |
| 19 | II. Known problems |
| 20 | |
| 21 | None. |
| 22 | |
| Alexandre Bounine | 50835e9 | 2014-08-08 14:22:12 -0700 | [diff] [blame] | 23 | III. DMA Engine Support |
| Alexandre Bounine | 48618fb | 2011-11-02 13:39:09 -0700 | [diff] [blame] | 24 | |
| Alexandre Bounine | 50835e9 | 2014-08-08 14:22:12 -0700 | [diff] [blame] | 25 | Tsi721 mport driver supports DMA data transfers between local system memory and |
| 26 | remote RapidIO devices. This functionality is implemented according to SLAVE |
| 27 | mode API defined by common Linux kernel DMA Engine framework. |
| 28 | |
| 29 | Depending on system requirements RapidIO DMA operations can be included/excluded |
| 30 | by setting CONFIG_RAPIDIO_DMA_ENGINE option. Tsi721 miniport driver uses seven |
| 31 | out of eight available BDMA channels to support DMA data transfers. |
| 32 | One BDMA channel is reserved for generation of maintenance read/write requests. |
| 33 | |
| 34 | If Tsi721 mport driver have been built with RAPIDIO_DMA_ENGINE support included, |
| 35 | this 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). |
| Alexandre Bounine | 48618fb | 2011-11-02 13:39:09 -0700 | [diff] [blame] | 38 | |
| 39 | IV. Version History |
| 40 | |
| Alexandre Bounine | 50835e9 | 2014-08-08 14:22:12 -0700 | [diff] [blame] | 41 | 1.1.0 - DMA operations re-worked to support data scatter/gather lists larger |
| 42 | than hardware buffer descriptors ring. |
| Alexandre Bounine | 48618fb | 2011-11-02 13:39:09 -0700 | [diff] [blame] | 43 | 1.0.0 - Initial driver release. |
| 44 | |
| 45 | V. 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. |