Re: [PATCH] NTB: ntb_hw_switchtec: add pre-requisites for NTB driver and misc updates
From: Bjorn Helgaas <helgaas@kernel.org>
Date: 2018-09-12 12:26:30
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On Wed, Sep 12, 2018 at 08:55:18AM +0000, Wesley.Sheng@microchip.com wrote:
From: Wesley Sheng <redacted> 1.add pre-requisites for NTB driver 2.misc updates change ntb hardware driver name to ntb_hw_switchtec
s/ ntb / NTB /
update the description of 2 partitions limit add reference to Linux Documentation/ntb.txt add use of term 'Command ID' add use of term 'Command Return Value' add a missing ')' Signed-off-by: Kelvin Cao <kelvin.cao@microchip.com> Signed-off-by: Wesley Yung <redacted>
I assume Kurt or Logan will take care of this.
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--- Documentation/switchtec.txt | 30 ++++++++++++++-------- 1 file changed, 20 insertions(+), 10 deletions(-)diff --git a/Documentation/switchtec.txt b/Documentation/switchtec.txt index f788264..40e839d 100644 --- a/Documentation/switchtec.txt +++ b/Documentation/switchtec.txt@@ -23,7 +23,7 @@ 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 bytes return code and up to 1KB of command specific +respond with a 4-byte return code and up to 1KB of command specific
This hunk looks malformed ("-" buried in middle of line above).
"Patch" complained that this patch was corrupted.
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data. The interface only processes a single command at a time.@@ -36,8 +36,8 @@ 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 four bytes will be interpreted as the command to run and - the remainder will be used as the input data. A write will send the + 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
Looks like whitespace at beginning of line is wrong here.
command to the firmware to begin processing. * Each write must be followed by exactly one read. Any double write will @@ -45,9 +45,9 @@ The char device has the following semantics: produce an error. * A read will block until the firmware completes the command and return - the four bytes of status 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 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.)
Also here.
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* The poll call will also be supported for userspace applications that 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: Non-Transparent Bridge (NTB) Driver =================================== -An NTB driver is provided for the switchtec hardware in switchtec_ntb. -Currently, it only supports switches configured with exactly 2 -partitions. It also requires the following configuration settings: +An NTB hardware driver is provided for the switchtec hardware in
"Switchtec" should be capitalized when used as a proper adjective like this. When used as the name of the driver, the lower-case "switchtec" is appropriate.
+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 partitions must be able to access each other's GAS spaces. +* 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.