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Kelvin Cao
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Merge branch 'release_4.13_to_4.14' into release_4.4_to_4.7
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README.rst

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@@ -23,7 +23,7 @@ The primary means of communicating with the Switchtec management firmware is
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through the Memory-mapped Remote Procedure Call (MRPC) interface.
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Commands are submitted to the interface with a 4-byte command
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identifier and up to 1KB of command specific data. The firmware will
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respond with a 4 bytes return code and up to 1KB of command specific
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respond with a 4-byte return code and up to 1KB of command specific
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data. The interface only processes a single command at a time.
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@@ -36,18 +36,18 @@ device: /dev/switchtec#, one for each management endpoint in the system.
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The char device has the following semantics:
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* A write must consist of at least 4 bytes and no more than 1028 bytes.
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The first four bytes will be interpreted as the command to run and
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the remainder will be used as the input data. A write will send the
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The first 4 bytes will be interpreted as the Command ID and the
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remainder will be used as the input data. A write will send the
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command to the firmware to begin processing.
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* Each write must be followed by exactly one read. Any double write will
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produce an error and any read that doesn't follow a write will
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produce an error.
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* A read will block until the firmware completes the command and return
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the four bytes of status plus up to 1024 bytes of output data. (The
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length will be specified by the size parameter of the read call --
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reading less than 4 bytes will produce an error.
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the 4-byte Command Return Value plus up to 1024 bytes of output
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data. (The length will be specified by the size parameter of the read
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call -- reading less than 4 bytes will produce an error.)
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* The poll call will also be supported for userspace applications that
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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:
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Non-Transparent Bridge (NTB) Driver
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===================================
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An NTB driver is provided for the switchtec hardware in switchtec_ntb.
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Currently, it only supports switches configured with exactly 2
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partitions. It also requires the following configuration settings:
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An NTB hardware driver is provided for the switchtec hardware in
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ntb_hw_switchtec. Currently, it only supports switches configured with
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exactly 2 NT partitions and zero or more non-NT partitions. It also requires
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the following configuration settings:
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* Both partitions must be able to access each other's GAS spaces.
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* Both NT partitions must be able to access each other's GAS spaces.
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Thus, the bits in the GAS Access Vector under Management Settings
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must be set to support this.
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* Kernel configuration MUST include support for NTB (CONFIG_NTB needs
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to be set)
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NT EP BAR 2 will be dynamically configured as a Direct Window, and
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the configuration file does not need to configure it explicitly.
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Please refer to Documentation/ntb.txt in Linux source tree for an overall
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understanding of the Linux NTB stack. ntb_hw_switchtec works as an NTB
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Hardware Driver in this stack.

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