@@ -23,7 +23,7 @@ The primary means of communicating with the Switchtec management firmware is
2323through the Memory-mapped Remote Procedure Call (MRPC) interface.
2424Commands are submitted to the interface with a 4-byte command
2525identifier and up to 1KB of command specific data. The firmware will
26- respond with a 4 bytes return code and up to 1KB of command specific
26+ respond with a 4-byte return code and up to 1KB of command specific
2727data. The interface only processes a single command at a time.
2828
2929
@@ -36,18 +36,18 @@ device: /dev/switchtec#, one for each management endpoint in the system.
3636The char device has the following semantics:
3737
3838* A write must consist of at least 4 bytes and no more than 1028 bytes.
39- The first four bytes will be interpreted as the command to run and
40- the remainder will be used as the input data. A write will send the
39+ The first 4 bytes will be interpreted as the Command ID and the
40+ remainder will be used as the input data. A write will send the
4141 command to the firmware to begin processing.
4242
4343* Each write must be followed by exactly one read. Any double write will
4444 produce an error and any read that doesn't follow a write will
4545 produce an error.
4646
4747* A read will block until the firmware completes the command and return
48- the four bytes of status plus up to 1024 bytes of output data. (The
49- length will be specified by the size parameter of the read call --
50- reading less than 4 bytes will produce an error.
48+ the 4-byte Command Return Value plus up to 1024 bytes of output
49+ data. (The length will be specified by the size parameter of the read
50+ call -- reading less than 4 bytes will produce an error.)
5151
5252* The poll call will also be supported for userspace applications that
5353 need to do other things while waiting for the command to complete.
@@ -83,10 +83,20 @@ The following IOCTLs are also supported by the device:
8383Non-Transparent Bridge (NTB) Driver
8484===================================
8585
86- An NTB driver is provided for the switchtec hardware in switchtec_ntb.
87- Currently, it only supports switches configured with exactly 2
88- partitions. It also requires the following configuration settings:
86+ An NTB hardware driver is provided for the switchtec hardware in
87+ ntb_hw_switchtec. Currently, it only supports switches configured with
88+ exactly 2 NT partitions and zero or more non-NT partitions. It also requires
89+ the following configuration settings:
8990
90- * Both partitions must be able to access each other's GAS spaces.
91+ * Both NT partitions must be able to access each other's GAS spaces.
9192 Thus, the bits in the GAS Access Vector under Management Settings
9293 must be set to support this.
94+ * Kernel configuration MUST include support for NTB (CONFIG_NTB needs
95+ to be set)
96+
97+ NT EP BAR 2 will be dynamically configured as a Direct Window, and
98+ the configuration file does not need to configure it explicitly.
99+
100+ Please refer to Documentation/ntb.txt in Linux source tree for an overall
101+ understanding of the Linux NTB stack. ntb_hw_switchtec works as an NTB
102+ Hardware Driver in this stack.
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