tsi721.rst (5067B)
1========================================================================= 2RapidIO subsystem mport driver for IDT Tsi721 PCI Express-to-SRIO bridge. 3========================================================================= 4 51. Overview 6=========== 7 8This driver implements all currently defined RapidIO mport callback functions. 9It supports maintenance read and write operations, inbound and outbound RapidIO 10doorbells, inbound maintenance port-writes and RapidIO messaging. 11 12To generate SRIO maintenance transactions this driver uses one of Tsi721 DMA 13channels. This mechanism provides access to larger range of hop counts and 14destination IDs without need for changes in outbound window translation. 15 16RapidIO messaging support uses dedicated messaging channels for each mailbox. 17For inbound messages this driver uses destination ID matching to forward messages 18into the corresponding message queue. Messaging callbacks are implemented to be 19fully compatible with RIONET driver (Ethernet over RapidIO messaging services). 20 211. Module parameters: 22 23- 'dbg_level' 24 - This parameter allows to control amount of debug information 25 generated by this device driver. This parameter is formed by set of 26 This parameter can be changed bit masks that correspond to the specific 27 functional block. 28 For mask definitions see 'drivers/rapidio/devices/tsi721.h' 29 This parameter can be changed dynamically. 30 Use CONFIG_RAPIDIO_DEBUG=y to enable debug output at the top level. 31 32- 'dma_desc_per_channel' 33 - This parameter defines number of hardware buffer 34 descriptors allocated for each registered Tsi721 DMA channel. 35 Its default value is 128. 36 37- 'dma_txqueue_sz' 38 - DMA transactions queue size. Defines number of pending 39 transaction requests that can be accepted by each DMA channel. 40 Default value is 16. 41 42- 'dma_sel' 43 - DMA channel selection mask. Bitmask that defines which hardware 44 DMA channels (0 ... 6) will be registered with DmaEngine core. 45 If bit is set to 1, the corresponding DMA channel will be registered. 46 DMA channels not selected by this mask will not be used by this device 47 driver. Default value is 0x7f (use all channels). 48 49- 'pcie_mrrs' 50 - override value for PCIe Maximum Read Request Size (MRRS). 51 This parameter gives an ability to override MRRS value set during PCIe 52 configuration process. Tsi721 supports read request sizes up to 4096B. 53 Value for this parameter must be set as defined by PCIe specification: 54 0 = 128B, 1 = 256B, 2 = 512B, 3 = 1024B, 4 = 2048B and 5 = 4096B. 55 Default value is '-1' (= keep platform setting). 56 57- 'mbox_sel' 58 - RIO messaging MBOX selection mask. This is a bitmask that defines 59 messaging MBOXes are managed by this device driver. Mask bits 0 - 3 60 correspond to MBOX0 - MBOX3. MBOX is under driver's control if the 61 corresponding bit is set to '1'. Default value is 0x0f (= all). 62 632. Known problems 64================= 65 66 None. 67 683. DMA Engine Support 69===================== 70 71Tsi721 mport driver supports DMA data transfers between local system memory and 72remote RapidIO devices. This functionality is implemented according to SLAVE 73mode API defined by common Linux kernel DMA Engine framework. 74 75Depending on system requirements RapidIO DMA operations can be included/excluded 76by setting CONFIG_RAPIDIO_DMA_ENGINE option. Tsi721 miniport driver uses seven 77out of eight available BDMA channels to support DMA data transfers. 78One BDMA channel is reserved for generation of maintenance read/write requests. 79 80If Tsi721 mport driver have been built with RAPIDIO_DMA_ENGINE support included, 81this driver will accept DMA-specific module parameter: 82 83 "dma_desc_per_channel" 84 - defines number of hardware buffer descriptors used by 85 each BDMA channel of Tsi721 (by default - 128). 86 874. Version History 88 89 ===== ==================================================================== 90 1.1.0 DMA operations re-worked to support data scatter/gather lists larger 91 than hardware buffer descriptors ring. 92 1.0.0 Initial driver release. 93 ===== ==================================================================== 94 955. License 96=========== 97 98 Copyright(c) 2011 Integrated Device Technology, Inc. All rights reserved. 99 100 This program is free software; you can redistribute it and/or modify it 101 under the terms of the GNU General Public License as published by the Free 102 Software Foundation; either version 2 of the License, or (at your option) 103 any later version. 104 105 This program is distributed in the hope that it will be useful, but WITHOUT 106 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 107 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 108 more details. 109 110 You should have received a copy of the GNU General Public License along with 111 this program; if not, write to the Free Software Foundation, Inc., 112 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.