From: Wesley Yung <[email protected]>
The ntb_hw_switchtec driver has requirements on kernel configuration
so we add these notes to the documentation and also clean up a few
other sentences in the documentation.
Signed-off-by: Wesley Yung <[email protected]>
Signed-off-by: Kelvin Cao <[email protected]>
Signed-off-by: Wesley Sheng <[email protected]>
---
Documentation/switchtec.txt | 30 ++++++++++++++++++++----------
1 file changed, 20 insertions(+), 10 deletions(-)
diff --git a/Documentation/switchtec.txt b/Documentation/switchtec.txt
index f788264..d6f04dcc 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
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
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.)
* 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
+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.
--
2.7.4
On 2018-10-10 8:42 a.m., Wesley Sheng wrote:
> From: Wesley Yung <[email protected]>
>
> The ntb_hw_switchtec driver has requirements on kernel configuration
> so we add these notes to the documentation and also clean up a few
> other sentences in the documentation.
>
> Signed-off-by: Wesley Yung <[email protected]>
> Signed-off-by: Kelvin Cao <[email protected]>
> Signed-off-by: Wesley Sheng <[email protected]>
Reviewed-by: Logan Gunthorpe <[email protected]>
[+cc Jon Mason]
On Wed, Oct 10, 2018 at 10:42:55PM +0800, Wesley Sheng wrote:
> From: Wesley Yung <[email protected]>
>
> The ntb_hw_switchtec driver has requirements on kernel configuration
> so we add these notes to the documentation and also clean up a few
> other sentences in the documentation.
>
> Signed-off-by: Wesley Yung <[email protected]>
> Signed-off-by: Kelvin Cao <[email protected]>
> Signed-off-by: Wesley Sheng <[email protected]>
I'm not sure who should really own this file:
$ ./scripts/get_maintainer.pl -f Documentation/switchtec.txt
Kurt Schwemmer <[email protected]> (maintainer:PCI DRIVER FOR MICROSEMI SWITCHTEC)
Logan Gunthorpe <[email protected]> (maintainer:PCI DRIVER FOR MICROSEMI SWITCHTEC)
Jonathan Corbet <[email protected]> (maintainer:DOCUMENTATION)
[email protected] (open list:PCI DRIVER FOR MICROSEMI SWITCHTEC)
[email protected] (open list:DOCUMENTATION)
[email protected] (open list)
and Jon (NTB driver core maintainer) has applied recent updates
to it.
But in the interest of forward progress, I applied this patch with
Logan's ack to pci/misc for v4.20.
> ---
> Documentation/switchtec.txt | 30 ++++++++++++++++++++----------
> 1 file changed, 20 insertions(+), 10 deletions(-)
>
> diff --git a/Documentation/switchtec.txt b/Documentation/switchtec.txt
> index f788264..d6f04dcc 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
> 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
> 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.)
>
> * 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
> +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.
> --
> 2.7.4
>
On 2018-10-11 10:27 a.m., Bjorn Helgaas wrote:
> I'm not sure who should really own this file:
>
> $ ./scripts/get_maintainer.pl -f Documentation/switchtec.txt
> Kurt Schwemmer <[email protected]> (maintainer:PCI DRIVER FOR MICROSEMI SWITCHTEC)
> Logan Gunthorpe <[email protected]> (maintainer:PCI DRIVER FOR MICROSEMI SWITCHTEC)
> Jonathan Corbet <[email protected]> (maintainer:DOCUMENTATION)
> [email protected] (open list:PCI DRIVER FOR MICROSEMI SWITCHTEC)
> [email protected] (open list:DOCUMENTATION)
> [email protected] (open list)
>
> and Jon (NTB driver core maintainer) has applied recent updates
> to it.
>
> But in the interest of forward progress, I applied this patch with
> Logan's ack to pci/misc for v4.20.
Thanks. I'm not really sure what's going on in the NTB tree these days
as Jon hasn't picked up anything in a while so it's probably better this
went through PCI. It was originally created through the PCI tree, there
shouldn't be any conflicts, and I can't see anyone else objecting.
Logan
On Wed, 10 Oct 2018 20:33:08 +0800
Wesley Sheng <[email protected]> wrote:
> The ntb_hw_switchtec driver has requirements on kernel configuration
> so we add these notes to the documentation and also clean up a few
> other sentences in the documentation.
>
> Signed-off-by: Wesley Yung <[email protected]>
> Signed-off-by: Kelvin Cao <[email protected]>
> Signed-off-by: Wesley Sheng <[email protected]>
So why all of these signoffs for such a small patch? Who is the actual
author of the patch?
Thanks,
jon
On 2018-10-12 11:30 a.m., Jonathan Corbet wrote:
> On Wed, 10 Oct 2018 20:33:08 +0800
> Wesley Sheng <[email protected]> wrote:
>
>> The ntb_hw_switchtec driver has requirements on kernel configuration
>> so we add these notes to the documentation and also clean up a few
>> other sentences in the documentation.
>>
>> Signed-off-by: Wesley Yung <[email protected]>
>> Signed-off-by: Kelvin Cao <[email protected]>
>> Signed-off-by: Wesley Sheng <[email protected]>
>
> So why all of these signoffs for such a small patch? Who is the actual
> author of the patch?
It was originally two very small patches from Mr. Yung[1] and Mr. Cao[2]
combined and then cleaned up for upstream by Mr. Sheng.
There will likely be a bit more of this as they intend on upstreaming
more of the work that has been done out-of-tree. I believe most of this
is minor bug fixes and small feature additions.
Logan
[1]
https://github.com/Microsemi/switchtec-kernel/commit/5e7e7709c8ce6f37163113a8b6282aa4a788b6a0
[2]
https://github.com/Microsemi/switchtec-kernel/commit/e25fbb7267a742d08ca0802e0a6886c183e8b7b4