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diff --git a/Documentation/switchtec.txt b/Documentation/switchtec.txt deleted file mode 100644 index 30d6a64e53f7..000000000000 --- a/Documentation/switchtec.txt +++ /dev/null @@ -1,102 +0,0 @@ -======================== -Linux Switchtec Support -======================== - -Microsemi's "Switchtec" line of PCI switch devices is already -supported by the kernel with standard PCI switch drivers. However, the -Switchtec device advertises a special management endpoint which -enables some additional functionality. This includes: - -* Packet and Byte Counters -* Firmware Upgrades -* Event and Error logs -* Querying port link status -* Custom user firmware commands - -The switchtec kernel module implements this functionality. - - -Interface -========= - -The primary means of communicating with the Switchtec management firmware is -through the Memory-mapped Remote Procedure Call (MRPC) interface. -Commands are submitted to the interface with a 4-byte command -identifier and up to 1KB of command specific data. The firmware will -respond with a 4-byte return code and up to 1KB of command-specific -data. The interface only processes a single command at a time. - - -Userspace Interface -=================== - -The MRPC interface will be exposed to userspace through a simple char -device: /dev/switchtec#, one for each management endpoint in the system. - -The char device has the following semantics: - -* A write must consist of at least 4 bytes and no more than 1028 bytes. - The first 4 bytes will be interpreted as the Command ID and the - remainder will be used as the input data. A write will send the - command to the firmware to begin processing. - -* Each write must be followed by exactly one read. Any double write will - produce an error and any read that doesn't follow a write will - produce an error. - -* A read will block until the firmware completes the command and return - the 4-byte Command Return Value plus up to 1024 bytes of output - data. (The length will be specified by the size parameter of the read - call -- reading less than 4 bytes will produce an error.) - -* The poll call will also be supported for userspace applications that - need to do other things while waiting for the command to complete. - -The following IOCTLs are also supported by the device: - -* SWITCHTEC_IOCTL_FLASH_INFO - Retrieve firmware length and number - of partitions in the device. - -* SWITCHTEC_IOCTL_FLASH_PART_INFO - Retrieve address and lengeth for - any specified partition in flash. - -* SWITCHTEC_IOCTL_EVENT_SUMMARY - Read a structure of bitmaps - indicating all uncleared events. - -* SWITCHTEC_IOCTL_EVENT_CTL - Get the current count, clear and set flags - for any event. This ioctl takes in a switchtec_ioctl_event_ctl struct - with the event_id, index and flags set (index being the partition or PFF - number for non-global events). It returns whether the event has - occurred, the number of times and any event specific data. The flags - can be used to clear the count or enable and disable actions to - happen when the event occurs. - By using the SWITCHTEC_IOCTL_EVENT_FLAG_EN_POLL flag, - you can set an event to trigger a poll command to return with - POLLPRI. In this way, userspace can wait for events to occur. - -* SWITCHTEC_IOCTL_PFF_TO_PORT and SWITCHTEC_IOCTL_PORT_TO_PFF convert - between PCI Function Framework number (used by the event system) - and Switchtec Logic Port ID and Partition number (which is more - user friendly). - - -Non-Transparent Bridge (NTB) Driver -=================================== - -An NTB hardware driver is provided for the Switchtec hardware in -ntb_hw_switchtec. Currently, it only supports switches configured with -exactly 2 NT partitions and zero or more non-NT partitions. It also requires -the following configuration settings: - -* Both NT partitions must be able to access each other's GAS spaces. - Thus, the bits in the GAS Access Vector under Management Settings - must be set to support this. -* Kernel configuration MUST include support for NTB (CONFIG_NTB needs - to be set) - -NT EP BAR 2 will be dynamically configured as a Direct Window, and -the configuration file does not need to configure it explicitly. - -Please refer to Documentation/ntb.txt in Linux source tree for an overall -understanding of the Linux NTB stack. ntb_hw_switchtec works as an NTB -Hardware Driver in this stack. |