[GIT PULL] linux-firmware: mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support

[GIT PULL] linux-firmware: mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support

[Vadym Kochan]

The following changes since commit 0f66b74b6267fce66395316308d88b0535aa3df2:

  cypress: update firmware for cyw54591 pcie (2021-06-09 07:12:02 -0400)

are available in the Git repository at:

  https://github.com/PLVision/linux-firmware.git mrvl-prestera

for you to fetch changes up to a43d95a48b8e8167e21fb72429d860c7961c2e32:

  mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support (2021-06-17 18:22:57 +0300)

----------------------------------------------------------------
Vadym Kochan (1):
      mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support

 mrvl/prestera/mvsw_prestera_fw-v3.0.img | Bin 13721584 -> 13721676 bytes
 1 file changed, 0 insertions(+), 0 deletions(-)

Re: [GIT PULL] linux-firmware: mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support

[Andrew Lunn]

On Thu, Jun 17, 2021 at 06:42:06PM +0300, Vadym Kochan wrote:
> The following changes since commit 0f66b74b6267fce66395316308d88b0535aa3df2:
> 
>   cypress: update firmware for cyw54591 pcie (2021-06-09 07:12:02 -0400)
> 
> are available in the Git repository at:
> 
>   https://github.com/PLVision/linux-firmware.git mrvl-prestera
> 
> for you to fetch changes up to a43d95a48b8e8167e21fb72429d860c7961c2e32:
> 
>   mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support (2021-06-17 18:22:57 +0300)
> 
> ----------------------------------------------------------------
> Vadym Kochan (1):
>       mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support
> 
>  mrvl/prestera/mvsw_prestera_fw-v3.0.img | Bin 13721584 -> 13721676 bytes
>  1 file changed, 0 insertions(+), 0 deletions(-)

Hi Vadym

You keep the version the same, but add new features? So what does the
version number actually mean? How does the driver know if should not
use the policer if it cannot tell old version 3.0 from new version
3.0?  How is a user supposed to know if they have old version 3.0
rather than new 3.0, when policer fails?

    Andrew

Re: [GIT PULL] linux-firmware: mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support

[Vadym Kochan]

Hi Andrew,

On Thu, Jun 17, 2021 at 06:45:14PM +0200, Andrew Lunn wrote:
> On Thu, Jun 17, 2021 at 06:42:06PM +0300, Vadym Kochan wrote:
> > The following changes since commit 0f66b74b6267fce66395316308d88b0535aa3df2:
> > 
> >   cypress: update firmware for cyw54591 pcie (2021-06-09 07:12:02 -0400)
> > 
> > are available in the Git repository at:
> > 
> >   https://github.com/PLVision/linux-firmware.git mrvl-prestera
> > 
> > for you to fetch changes up to a43d95a48b8e8167e21fb72429d860c7961c2e32:
> > 
> >   mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support (2021-06-17 18:22:57 +0300)
> > 
> > ----------------------------------------------------------------
> > Vadym Kochan (1):
> >       mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support
> > 
> >  mrvl/prestera/mvsw_prestera_fw-v3.0.img | Bin 13721584 -> 13721676 bytes
> >  1 file changed, 0 insertions(+), 0 deletions(-)
> 
> Hi Vadym
> 
> You keep the version the same, but add new features? So what does the
> version number actually mean? How does the driver know if should not
> use the policer if it cannot tell old version 3.0 from new version
> 3.0?  How is a user supposed to know if they have old version 3.0
> rather than new 3.0, when policer fails?
> 
>     Andrew

So the last 'sub' x.x.1 version will be showed in dmesg output and via:

    $ ethtool -i $PORT

    ...
    firmware-version: 3.0.1
    ...

The older driver version will not use the policer feature. I am not sure
if I need to add a check for 3.0.1 in the newer one which will have the
policer changes. So may be the only case which can be handled (in new
driver changes with policer code) is to check if the FW is not older
than 3.0.1 during the validation of police rules.

For this reason I decided to do not increase the supported version
MIN.MAJ but only the SUB (last one).

Re: [GIT PULL] linux-firmware: mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support

[Andrew Lunn]

On Thu, Jun 17, 2021 at 07:58:24PM +0300, Vadym Kochan wrote:
> Hi Andrew,
> 
> On Thu, Jun 17, 2021 at 06:45:14PM +0200, Andrew Lunn wrote:
> > On Thu, Jun 17, 2021 at 06:42:06PM +0300, Vadym Kochan wrote:
> > > The following changes since commit 0f66b74b6267fce66395316308d88b0535aa3df2:
> > > 
> > >   cypress: update firmware for cyw54591 pcie (2021-06-09 07:12:02 -0400)
> > > 
> > > are available in the Git repository at:
> > > 
> > >   https://github.com/PLVision/linux-firmware.git mrvl-prestera
> > > 
> > > for you to fetch changes up to a43d95a48b8e8167e21fb72429d860c7961c2e32:
> > > 
> > >   mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support (2021-06-17 18:22:57 +0300)
> > > 
> > > ----------------------------------------------------------------
> > > Vadym Kochan (1):
> > >       mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support
> > > 
> > >  mrvl/prestera/mvsw_prestera_fw-v3.0.img | Bin 13721584 -> 13721676 bytes
> > >  1 file changed, 0 insertions(+), 0 deletions(-)
> > 
> > Hi Vadym
> > 
> > You keep the version the same, but add new features? So what does the
> > version number actually mean? How does the driver know if should not
> > use the policer if it cannot tell old version 3.0 from new version
> > 3.0?  How is a user supposed to know if they have old version 3.0
> > rather than new 3.0, when policer fails?
> > 
> >     Andrew
> 
> So the last 'sub' x.x.1 version will be showed in dmesg output and via:
> 
>     $ ethtool -i $PORT
> 
>     ...
>     firmware-version: 3.0.1

That is pretty unfriendly, the filename saying one thing, the kernel
another.

If you look back in the git history, are there other firmware blobs
which get updated while retaining the same version? If this is very
unusual, you probably should not be doing it. If it is common
practice, then i will be surprised, and it is probably acceptable.

I suppose you could consider another alternative: Make
mrvl/prestera/mvsw_prestera_fw-v3.0.img a symbolic link, and it would
point to mrvl/prestera/mvsw_prestera_fw-v3.0.1.img.

	  Andrew

Re: [GIT PULL] linux-firmware: mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support

[Vadym Kochan]

Hi Andrew,

On Fri, Jun 18, 2021 at 03:18:16AM +0200, Andrew Lunn wrote:
> On Thu, Jun 17, 2021 at 07:58:24PM +0300, Vadym Kochan wrote:
> > Hi Andrew,
> > 
> > On Thu, Jun 17, 2021 at 06:45:14PM +0200, Andrew Lunn wrote:
> > > On Thu, Jun 17, 2021 at 06:42:06PM +0300, Vadym Kochan wrote:
> > > > The following changes since commit 0f66b74b6267fce66395316308d88b0535aa3df2:
> > > > 
> > > >   cypress: update firmware for cyw54591 pcie (2021-06-09 07:12:02 -0400)
> > > > 
> > > > are available in the Git repository at:
> > > > 
> > > >   https://github.com/PLVision/linux-firmware.git mrvl-prestera
> > > > 
> > > > for you to fetch changes up to a43d95a48b8e8167e21fb72429d860c7961c2e32:
> > > > 
> > > >   mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support (2021-06-17 18:22:57 +0300)
> > > > 
> > > > ----------------------------------------------------------------
> > > > Vadym Kochan (1):
> > > >       mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support
> > > > 
> > > >  mrvl/prestera/mvsw_prestera_fw-v3.0.img | Bin 13721584 -> 13721676 bytes
> > > >  1 file changed, 0 insertions(+), 0 deletions(-)
> > > 
> > > Hi Vadym
> > > 
> > > You keep the version the same, but add new features? So what does the
> > > version number actually mean? How does the driver know if should not
> > > use the policer if it cannot tell old version 3.0 from new version
> > > 3.0?  How is a user supposed to know if they have old version 3.0
> > > rather than new 3.0, when policer fails?
> > > 
> > >     Andrew
> > 
> > So the last 'sub' x.x.1 version will be showed in dmesg output and via:
> > 
> >     $ ethtool -i $PORT
> > 
> >     ...
> >     firmware-version: 3.0.1
> 
> That is pretty unfriendly, the filename saying one thing, the kernel
> another.
> 
> If you look back in the git history, are there other firmware blobs
> which get updated while retaining the same version? If this is very
> unusual, you probably should not be doing it. If it is common
> practice, then i will be surprised, and it is probably acceptable.
> 
> I suppose you could consider another alternative: Make
> mrvl/prestera/mvsw_prestera_fw-v3.0.img a symbolic link, and it would
> point to mrvl/prestera/mvsw_prestera_fw-v3.0.1.img.
> 
> 	  Andrew

I just picked some from the git log:

    48237834129d ("QCA: Update Bluetooth firmware for QCA6174")

this just updates the binary and description says that it updates
to v26.

Not sure if it is good example.

But anyway, I agree with you that better if new changes also reflects
the FW binary name (version) so it will be easy to find out which FW binary
have or not particular features.

So I think better to add new FW 3.1 binary ?

Thank you,

Re: [GIT PULL] linux-firmware: mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support

[Andrew Lunn]

> I just picked some from the git log:
> 
>     48237834129d ("QCA: Update Bluetooth firmware for QCA6174")
> 
> this just updates the binary and description says that it updates
> to v26.
> 
> Not sure if it is good example.

The filename is qca/rampatch_usb_00000302.bin. If you look at
drivers/bluetooth/btusb.c you can see that 00000302 is the version of
the ROM in the device which is being patched. So there is no
expectation of knowing the firmware version from the firmware
filename.

> But anyway, I agree with you that better if new changes also reflects
> the FW binary name (version) so it will be easy to find out which FW binary
> have or not particular features.
> 
> So I think better to add new FW 3.1 binary ?

Probably. But please consider your whole upgrade story. You are
changing the firmware version quite frequently. How do end users cope
with this? Is the driver going to support 3.1, 3.0 and 2.0? Or just
3.1 and 2.0?

Do you have more features in firmware 3.1 you need to add driver
support for? Or can we expect a 3.2 in a few weeks time? What are your
users expectations at the moment? It could be, you don't consider the
driver has enough features at the moment that anybody other than early
adopters playing with it would consider using it. That you don't
expect real use of it for another six months, or a year. If that is
true, you probably can be a bit more disruptive at the moment. But
when you have a production ready driver, you really do need to
consider how your users deal with upgrades, keeping the firmware
version stable for a longer period of time.

	Andrew

Re: [GIT PULL] linux-firmware: mrvl: prestera: Update Marvell Prestera Switchdev v3.0 with policer support

[Vadym Kochan]

Hi Andrew,

On Fri, Jun 18, 2021 at 03:41:39PM +0200, Andrew Lunn wrote:
> > I just picked some from the git log:
> > 
> >     48237834129d ("QCA: Update Bluetooth firmware for QCA6174")
> > 
> > this just updates the binary and description says that it updates
> > to v26.
> > 
> > Not sure if it is good example.
> 
> The filename is qca/rampatch_usb_00000302.bin. If you look at
> drivers/bluetooth/btusb.c you can see that 00000302 is the version of
> the ROM in the device which is being patched. So there is no
> expectation of knowing the firmware version from the firmware
> filename.
> 
> > But anyway, I agree with you that better if new changes also reflects
> > the FW binary name (version) so it will be easy to find out which FW binary
> > have or not particular features.
> > 
> > So I think better to add new FW 3.1 binary ?
> 
> Probably. But please consider your whole upgrade story. You are
> changing the firmware version quite frequently. How do end users cope
> with this? Is the driver going to support 3.1, 3.0 and 2.0? Or just
> 3.1 and 2.0?

I think 3.1, 3.0 (still need to check about this) and 2.0, and the
driver need to be changed to use array of versions rather the previous
hardcoded value.

> 
> Do you have more features in firmware 3.1 you need to add driver
> support for? Or can we expect a 3.2 in a few weeks time? What are your
> users expectations at the moment? It could be, you don't consider the
> driver has enough features at the moment that anybody other than early
> adopters playing with it would consider using it. That you don't
> expect real use of it for another six months, or a year. If that is
> true, you probably can be a bit more disruptive at the moment. But
> when you have a production ready driver, you really do need to
> consider how your users deal with upgrades, keeping the firmware
> version stable for a longer period of time.

Thats, actually true, at this stage the FW can be updated frequently
because of bringing new offloading support. And you are right that
currently this driver is mostly in the sandbox mode. But even for the
earlier adopters looks like it is good to keep the version consistency.

For this particular update it has missing small changes for policer and
routing offloading (so it is kind of fix for 3.0 version). So, for
easiness it would be good to just replace the current 3.0 version, but
for consistency - better to use some extra version.

> 
> 	Andrew