Re: [PATCH v3 2/2] doc: add Arkville FX2 PCIe device description

[Ferruh Yigit <ferruh.yigit@amd.com>]

On 2/11/2023 3:07 AM, Shepard Siegel wrote:
> Hi Ferruh,
> 
> I don't think the submission system will allow your request of a single
> patch with both a code change and document change since they are in
> different directories. I must say I'm confused by your request. In the
> current v3 which is not your preference, we split up the new device into
> the 0001 and the doc on the new device in the 0002.
> 

Hi Shepard,

We are accepting doc and code changes in a single patch, indeed this is
preferred to have them together (although they are in different folders)

The logic is if someone looks the git history of specific document
update she can find relevant code change, or vice versa. If they are
separate and user finds a document that mentions a feature is enabled,
it can be challenging to find when/where that feature is added in the code.

> Your current ask of "Can you please add new device related documentation
> to patch that adds new device?" was what we did back on v2. Guessing you
> don't like the mention of any other devices in the FX2 addition?
> 
> It feels crazy to have to have three different patches to essentially
> add a one-liner to our PCIe device alowlist! Am I making this way more
> complicated than it needs to be?
> 

I have no intention to make more complicated, but that one line change
is adding a new device support, so it is important change to have its
own patch. It may even require a release notes update and web page
update later.

Your initial version was doing documentation update, and one of that
update was documenting a device as supported although it is not in the
code. You think it is not a bit deal to document unsupported devices as
supported, but I disagree.

My ask is simple, do the code update to support new device and relevant
doc update for new device in one patch, and rest of the documentation
updates in another.

Please reach out to me from slack/IRC if it is still confusing.

> We will produce the sequence of three patches in the morning. 
> 
> Would a cover letter help explain when we are doing with this patch?
> If there are elements that are not clear, let me know and we will work
> to clarify it.
> 
> Thank you for your efforts in this and countless other DPDK pushes!
> 
> best, Shep
> 
> 
> 
> 
> On Fri, Feb 10, 2023 at 9:13 PM Ferruh Yigit <ferruh.yigit@amd.com
> <mailto:ferruh.yigit@amd.com>> wrote:
> 
>     On 2/11/2023 1:26 AM, Shepard Siegel wrote:
>     > Update net/ark guide for clarity.
>     > Include list of FX0, FX1 and FX2 PCIe devices.
>     >
>     > Signed-off-by: Shepard Siegel <shepard.siegel@atomicrules.com
>     <mailto:shepard.siegel@atomicrules.com>>
>     > ---
>     >  doc/guides/nics/ark.rst | 20 ++++++++++++++++++++
>     >  1 file changed, 20 insertions(+)
>     >
>     > diff --git a/doc/guides/nics/ark.rst b/doc/guides/nics/ark.rst
>     > index ba00f14e80..39cd75064d 100644
>     > --- a/doc/guides/nics/ark.rst
>     > +++ b/doc/guides/nics/ark.rst
>     > @@ -52,6 +52,10 @@ board. While specific capabilities such as
>     number of physical
>     >  hardware queue-pairs are negotiated; the driver is designed to
>     >  remain constant over a broad and extendable feature set.
>     > 
>     > +* FPGA Vendors Supported: AMD/Xilinx and Intel
>     > +* Number of RX/TX Queue-Pairs: up to 128
>     > +* PCIe Endpoint Technology: Gen3, Gen4, Gen5
>     > +
>     >  Intentionally, Arkville by itself DOES NOT provide common NIC
>     >  capabilities such as offload or receive-side scaling (RSS).
>     >  These capabilities would be viewed as a gate-level "tax" on
>     > @@ -302,6 +306,20 @@ ARK PMD supports the following Arkville RTL
>     PCIe instances including:
>     >  * ``1d6c:101c`` - AR-ARK-SRIOV-VF [Arkville Virtual Function]
>     >  * ``1d6c:101e`` - AR-ARKA-FX1 [Arkville 64B DPDK Data Mover for
>     Agilex R-Tile]
>     >  * ``1d6c:101f`` - AR-TK242 [2x100GbE Packet Capture Device]
>     > +* ``1d6c:1022`` - AR-ARKA-FX2 [Arkville 128B DPDK Data Mover for
>     Agilex]
> 
>     Can you please add new device related documentation to patch that adds
>     new device?
>     At least above line is related to it, but if any other updates in this
>     document is related to this new device that part also can go to
>     other patch.
> 
>     Or if it make more sense you can first introduce the document update
>     patch for old devices, and later add new device and new device related
>     documentation, like:
> 
>     First patch adds:
>       +* ARK-FX0 - 256-bit 32B datapath (PCIe Gen3, Gen4)
>       +* ARK-FX1 - 512-bit 64B datapath (PCIe Gen3, Gen4, Gen5)
> 
>     Second patch adds new device and appends following:
>       +* ARK-FX2 - 1024-bit 128B datapath (PCIe Gen5x16 Only)
> 
> 
>     > +
>     > +Arkville RTL Core Configurations
>     > +-------------------------------------
>     > +
>     > +Arkville's RTL core may be configured by the user for three different
>     > +datapath widths to balance throughput against FPGA logic area.
>     The ARK PMD
>     > +has introspection on the RTL core configuration and acts accordingly.
>     > +All three configurations present identical RTL user-facing AXI stream
>     > +interfaces for both AMD/Xilinx and Intel FPGAs.
>     > +
>     > +* ARK-FX0 - 256-bit 32B datapath (PCIe Gen3, Gen4)
>     > +* ARK-FX1 - 512-bit 64B datapath (PCIe Gen3, Gen4, Gen5)
>     > +* ARK-FX2 - 1024-bit 128B datapath (PCIe Gen5x16 Only)
>     > 
>     >  DPDK and Arkville Firmware Versioning
>     >  -------------------------------------
>     > @@ -334,6 +352,8 @@ Supported Features
>     >  ------------------
>     > 
>     >  * Dynamic ARK PMD extensions
>     > +* Dynamic per-queue MBUF (re)sizing up to 32KB
>     > +* SR-IOV, VF-based queue-segregation
>     >  * Multiple receive and transmit queues
>     >  * Jumbo frames up to 9K
>     >  * Hardware Statistics
>