Re: [PATCH 0/7] towards QE support on ARM

[Li Yang]

On Tue, Oct 22, 2019 at 9:54 PM Qiang Zhao  wrote:
>
> On 22/10/2019 18:18, Rasmus Villemoes  wrote:
> > -Original Message-
> > From: Rasmus Villemoes 
> > Sent: 2019年10月22日 18:18
> > To: Qiang Zhao ; Leo Li 
> > Cc: Timur Tabi ; Greg Kroah-Hartman
> > ; linux-ker...@vger.kernel.org;
> > linux-ser...@vger.kernel.org; Jiri Slaby ;
> > linuxppc-dev@lists.ozlabs.org; linux-arm-ker...@lists.infradead.org
> > Subject: Re: [PATCH 0/7] towards QE support on ARM
> >
> > On 22/10/2019 04.24, Qiang Zhao wrote:
> > > On Mon, Oct 22, 2019 at 6:11 AM Leo Li wrote
> >
> > >> Right.  I'm really interested in getting this applied to my tree and
> > >> make it upstream.  Zhao Qiang, can you help to review Rasmus's
> > >> patches and comment?
> > >
> > > As you know, I maintained a similar patchset removing PPC, and someone
> > told me qe_ic should moved into drivers/irqchip/.
> > > I also thought qe_ic is a interrupt control driver, should be moved into 
> > > dir
> > irqchip.
> >
> > Yes, and I also plan to do that at some point. However, that's orthogonal to
> > making the driver build on ARM, so I don't want to mix the two. Making it
> > usable on ARM is my/our priority currently.
> >
> > I'd appreciate your input on my patches.
>
> Yes, we can put this patchset in first place, ensure it can build and work on 
> ARM, then push another patchset to move qe_ic.

Right.  I would only accept a patch series that can really build and
work on ARM.  At least the current out-of-tree patches can make it
work on ARM.  If we accept partial changes, there is no way to make it
work on the latest kernel on ARM then.

Regards,
Leo

RE: [PATCH 0/7] towards QE support on ARM

[Qiang Zhao]

On 22/10/2019 18:18, Rasmus Villemoes  wrote:
> -Original Message-
> From: Rasmus Villemoes 
> Sent: 2019年10月22日 18:18
> To: Qiang Zhao ; Leo Li 
> Cc: Timur Tabi ; Greg Kroah-Hartman
> ; linux-ker...@vger.kernel.org;
> linux-ser...@vger.kernel.org; Jiri Slaby ;
> linuxppc-dev@lists.ozlabs.org; linux-arm-ker...@lists.infradead.org
> Subject: Re: [PATCH 0/7] towards QE support on ARM
> 
> On 22/10/2019 04.24, Qiang Zhao wrote:
> > On Mon, Oct 22, 2019 at 6:11 AM Leo Li wrote
> 
> >> Right.  I'm really interested in getting this applied to my tree and
> >> make it upstream.  Zhao Qiang, can you help to review Rasmus's
> >> patches and comment?
> >
> > As you know, I maintained a similar patchset removing PPC, and someone
> told me qe_ic should moved into drivers/irqchip/.
> > I also thought qe_ic is a interrupt control driver, should be moved into dir
> irqchip.
> 
> Yes, and I also plan to do that at some point. However, that's orthogonal to
> making the driver build on ARM, so I don't want to mix the two. Making it
> usable on ARM is my/our priority currently.
> 
> I'd appreciate your input on my patches.

Yes, we can put this patchset in first place, ensure it can build and work on 
ARM, then push another patchset to move qe_ic.

Best Regards,
Qiang

Re: [PATCH 0/7] towards QE support on ARM

[Christophe Leroy]

On 10/18/2019 12:52 PM, Rasmus Villemoes wrote:

There have been several attempts in the past few years to allow
building the QUICC engine drivers for platforms other than PPC. This
is (the beginning of) yet another attempt. I hope I can get someone to
pick up these relatively trivial patches (I _think_ they shouldn't
change functionality at all), and then I'll continue slowly working
towards removing the PPC32 dependency for CONFIG_QUICC_ENGINE.

Tested on an MPC8309-derived board.

Rasmus Villemoes (7):
   soc: fsl: qe: remove space-before-tab
   soc: fsl: qe: drop volatile qualifier of struct qe_ic::regs
   soc: fsl: qe: avoid ppc-specific io accessors
   soc: fsl: qe: replace spin_event_timeout by readx_poll_timeout_atomic
   serial: make SERIAL_QE depend on PPC32
   serial: ucc_uart.c: explicitly include asm/cpm.h
   soc/fsl/qe/qe.h: remove include of asm/cpm.h


Please copy the entire series to linuxppc-dev list. We are missing 5/7 
and 7/7 (see 
https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=137048)


Christophe



  drivers/soc/fsl/qe/gpio.c | 30 
  drivers/soc/fsl/qe/qe.c   | 44 +++
  drivers/soc/fsl/qe/qe_ic.c|  8 ++---
  drivers/soc/fsl/qe/qe_ic.h|  2 +-
  drivers/soc/fsl/qe/qe_io.c| 40 ++---
  drivers/soc/fsl/qe/qe_tdm.c   |  8 ++---
  drivers/soc/fsl/qe/ucc.c  | 12 +++
  drivers/soc/fsl/qe/ucc_fast.c | 66 ++-
  drivers/soc/fsl/qe/ucc_slow.c | 38 ++--
  drivers/soc/fsl/qe/usb.c  |  2 +-
  drivers/tty/serial/Kconfig|  1 +
  drivers/tty/serial/ucc_uart.c |  1 +
  include/soc/fsl/qe/qe.h   |  1 -
  13 files changed, 126 insertions(+), 127 deletions(-)

Re: [PATCH 0/7] towards QE support on ARM

[Rasmus Villemoes]

On 22/10/2019 04.24, Qiang Zhao wrote:
> On Mon, Oct 22, 2019 at 6:11 AM Leo Li wrote

>> Right.  I'm really interested in getting this applied to my tree and make it
>> upstream.  Zhao Qiang, can you help to review Rasmus's patches and
>> comment?
> 
> As you know, I maintained a similar patchset removing PPC, and someone told 
> me qe_ic should moved into drivers/irqchip/.
> I also thought qe_ic is a interrupt control driver, should be moved into dir 
> irqchip.

Yes, and I also plan to do that at some point. However, that's
orthogonal to making the driver build on ARM, so I don't want to mix the
two. Making it usable on ARM is my/our priority currently.

I'd appreciate your input on my patches.

Rasmus

Re: [PATCH 0/7] towards QE support on ARM

[Rasmus Villemoes]

On 22/10/2019 00.11, Li Yang wrote:
> On Mon, Oct 21, 2019 at 3:46 AM Rasmus Villemoes
>  wrote:
>>

>>> Can you try the 4.14 branch from a newer LSDK release?  LS1021a should
>>> be supported platform on LSDK.  If it is broken, something is wrong.
>>
>> What newer release? LSDK-18.06-V4.14 is the latest -V4.14 tag at
>> https://github.com/qoriq-open-source/linux.git, and identical to the
> 
> That tree has been abandoned for a while, we probably should state
> that in the github.  The latest tree can be found at
> https://source.codeaurora.org/external/qoriq/qoriq-components/linux/

Ah. FYI, googling "LSDK" gives https://lsdk.github.io as one of the
first hits, and (apart from itself being a github url) that says on the
front page "Disaggregated components of LSDK are available in github.".
But yes, navigating to the Components tab and from there to lsdk linux
one does get directed at codeaurora.

>> In any case, we have zero interest in running an NXP kernel. Maybe I
>> should clarify what I meant by "based on commits from" above: We're
>> currently running a mainline 4.14 kernel on LS1021A, with a few patches
>> inspired from the NXP 4.1 branch applied on top - but also with some
>> manual fixes for e.g. the pvr_version_is() issue. Now we want to move
>> that to a 4.19-based kernel (so that it aligns with our MPC8309 platform).
> 
> We also provide 4.19 based kernel in the codeaurora repo.  I think it
> will be helpful to reuse patches there if you want to make your own
> tree.

Again, we don't want to run off an NXP kernel, we want to get the
necessary pieces upstream. For now, we have to live with a patched 4.19
kernel, but hopefully by the time we switch to 5.x (for some x >= 5) we
don't need to supply anything other than our own .dts and defconfig.

>> Yes, as I said, I wanted to try a fresh approach since Zhao
>> Qiang's patches seemed to be getting nowhere. Splitting the patches into
>> smaller pieces is definitely part of that - for example, the completely
>> trivial whitespace fix in patch 1 is to make sure the later coccinelle
>> generated patch is precisely that (i.e., a later respin can just rerun
>> the coccinelle script, with zero manual fixups). I also want to avoid
>> mixing the ppcism cleanups with other things (e.g. replacing some
>> of_get_property() by of_property_read_u32()). And the "testing on ARM"
>> part comes once I get to actually building on ARM. But there's not much
>> point doing all that unless there's some indication that this can be
>> applied to some tree that actually feeds into Linus', which is why I
>> started with a few trivial patches and precisely to start this discussion.
> 
> Right.  I'm really interested in getting this applied to my tree and
> make it upstream.  Zhao Qiang, can you help to review Rasmus's patches
> and comment?

Thanks, this is exactly what I was hoping for. Even just getting these
first rather trivial patches (in that they don't attempt to build for
ARM, or change functionality at all for PPC) merged for 5.5 would reduce
the amount of out-of-tree patches that we (and NXP for that matter)
would have to carry. I'll take the above as a go-ahead for me to try to
post more patches working towards enabling some of the QE drivers for ARM.

Rasmus

RE: [PATCH 0/7] towards QE support on ARM

[Qiang Zhao]

On Mon, Oct 22, 2019 at 6:11 AM Leo Li wrote
> -Original Message-
> From: Li Yang 
> Sent: 2019年10月22日 6:11
> To: Rasmus Villemoes 
> Cc: Timur Tabi ; Greg Kroah-Hartman
> ; linux-ker...@vger.kernel.org;
> linux-ser...@vger.kernel.org; Jiri Slaby ;
> linuxppc-dev@lists.ozlabs.org; linux-arm-ker...@lists.infradead.org; Qiang
> Zhao 
> Subject: Re: [PATCH 0/7] towards QE support on ARM
> 
> On Mon, Oct 21, 2019 at 3:46 AM Rasmus Villemoes
>  wrote:
> >
> > On 18/10/2019 23.52, Li Yang wrote:
> > > On Fri, Oct 18, 2019 at 3:54 PM Rasmus Villemoes
> > >  wrote:
> > >>
> > >> On 18/10/2019 22.16, Leo Li wrote:
> > >>>
> > >>>>
> > >>>> There have been several attempts in the past few years to allow
> > >>>> building the QUICC engine drivers for platforms other than PPC.
> > >>>> This is (the beginning of) yet another attempt. I hope I can get
> > >>>> someone to pick up these relatively trivial patches (I _think_
> > >>>> they shouldn't change functionality at all), and then I'll
> > >>>> continue slowly working towards removing the PPC32 dependency for
> CONFIG_QUICC_ENGINE.
> > >>>
> > >>> Hi Rasmus,
> > >>>
> > >>> I don't fully understand the motivation of this work.  As far as I know
> the QUICC ENGINE is only used on PowerPC based SoCs.
> > >>
> > >> Hm, you're not the Leo Li that participated in this thread
> > >>
> <https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.ke
> rnel.org%2Flkml%2FAM3PR04MB11857AE8D2B0BE56121B97D391C90%40A
> M3PR04MB1185.eurprd04.prod.outlook.com%2FT%2F%23udata=02%7
> C01%7Cqiang.zhao%40nxp.com%7C1ba8c50c2db14b22bef608d756739d82%
> 7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C6370729268771788
> 75sdata=k4zM75OczXwZF%2Br9ec4RxiVR2a%2F8GhSZmK70JYddIck%3
> Dreserved=0>?
> > >
> > > Oops, I totally forgot about this discussion which is just three
> > > years ago.  :)  The QE-HDLC on LS1021a is kind of a special case.
> > >
> > >>
> > >>
> > >>  Can you give an example on how is it used on ARM system?
> > >>
> > >> LS1021A, for example, which is the one I'm aiming for getting fully
> > >> supported in mainline.
> > >> <https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2F
> > >>
> www.nxp.com%2Fproducts%2Fprocessors-and-microcontrollers%2Farm-proc
> > >> essors%2Flayerscape-communication-process%2Fqoriq-layerscape-1021a-
> > >>
> dual-core-communications-processor-with-lcd-controller%3ALS1021A
> > >>
> p;data=02%7C01%7Cqiang.zhao%40nxp.com%7C1ba8c50c2db14b22bef608d
> 7567
> > >>
> 39d82%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C6370729268
> 771788
> > >>
> 75sdata=vqPYSZqEv6vCEIxJshLuA4gngh9J4IsFAQrTwJKMjm4%3Dr
> es
> > >> erved=0>
> > >>
> > >> The forks at
> > >>
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.
> com%2Fqoriq-open-source%2Flinux.gitdata=02%7C01%7Cqiang.zhao%
> 40nxp.com%7C1ba8c50c2db14b22bef608d756739d82%7C686ea1d3bc2b4c6
> fa92cd99c5c301635%7C0%7C0%7C637072926877178875sdata=v4eG
> 4KqGTWQkQHp%2FYg2OHCKITLWaOgH64JYpY%2B1LilA%3Dreserved=0
> have various degrees of support (grep for commits saying stuff like "remove
> PPCisms"
> > >> - some versions can be found on
> > >> <https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2F
> > >>
> lore.kernel.org%2Flkml%2F%3Fq%3Dremove%2Bppcismsdata=02%7C0
> 1%7
> > >>
> Cqiang.zhao%40nxp.com%7C1ba8c50c2db14b22bef608d756739d82%7C686e
> a1d3
> > >>
> bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637072926877178875sdat
> a=i2WdKNHLV68a1mTOMQ%2FoMr0y5ee8edS07xq61M8%2BvPU%3Dr
> eserved=0>). Our current kernel is based on commits from the now-vanished
> 4.1 branch, and unfortunately at least the 4.14 branch (LSDK-18.06-V4.14)
> trivially doesn't build on ARM, despite the PPC32 dependency having been
> removed from CONFIG_QUICC_ENGINE.
> > >
> > > Can you try the 4.14 branch from a newer LSDK release?  LS1021a
> > > should be supported platform on LSDK.  If it is broken, something is
> wrong.
> >
> > What newer release? LSDK-18.06-V4.14 is the latest -V4.14 tag at
> > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgith
> >
> ub.com%2Fqoriq-open-source%2Flinux.gitdata=02%7C01%7Cqiang.zha
> o%4
> >
> 0nxp.com%7C1ba8c50c2db14b22bef

Re: [PATCH 0/7] towards QE support on ARM

[Li Yang]

On Mon, Oct 21, 2019 at 3:46 AM Rasmus Villemoes
 wrote:
>
> On 18/10/2019 23.52, Li Yang wrote:
> > On Fri, Oct 18, 2019 at 3:54 PM Rasmus Villemoes
> >  wrote:
> >>
> >> On 18/10/2019 22.16, Leo Li wrote:
> >>>
> 
>  There have been several attempts in the past few years to allow building 
>  the
>  QUICC engine drivers for platforms other than PPC. This is (the 
>  beginning of)
>  yet another attempt. I hope I can get someone to pick up these relatively
>  trivial patches (I _think_ they shouldn't change functionality at all), 
>  and then
>  I'll continue slowly working towards removing the PPC32 dependency for
>  CONFIG_QUICC_ENGINE.
> >>>
> >>> Hi Rasmus,
> >>>
> >>> I don't fully understand the motivation of this work.  As far as I know 
> >>> the QUICC ENGINE is only used on PowerPC based SoCs.
> >>
> >> Hm, you're not the Leo Li that participated in this thread
> >> ?
> >
> > Oops, I totally forgot about this discussion which is just three years
> > ago.  :)  The QE-HDLC on LS1021a is kind of a special case.
> >
> >>
> >>
> >>  Can you give an example on how is it used on ARM system?
> >>
> >> LS1021A, for example, which is the one I'm aiming for getting fully
> >> supported in mainline.
> >> 
> >>
> >> The forks at https://github.com/qoriq-open-source/linux.git have various
> >> degrees of support (grep for commits saying stuff like "remove PPCisms"
> >> - some versions can be found on
> >> ). Our current kernel is
> >> based on commits from the now-vanished 4.1 branch, and unfortunately at
> >> least the 4.14 branch (LSDK-18.06-V4.14) trivially doesn't build on ARM,
> >> despite the PPC32 dependency having been removed from CONFIG_QUICC_ENGINE.
> >
> > Can you try the 4.14 branch from a newer LSDK release?  LS1021a should
> > be supported platform on LSDK.  If it is broken, something is wrong.
>
> What newer release? LSDK-18.06-V4.14 is the latest -V4.14 tag at
> https://github.com/qoriq-open-source/linux.git, and identical to the

That tree has been abandoned for a while, we probably should state
that in the github.  The latest tree can be found at
https://source.codeaurora.org/external/qoriq/qoriq-components/linux/

> linux-4.14 branch. And despite commit 4c33e2d0576b removing the PPC32
> dependency from QUICC_ENGINE, it clearly hasn't been built on arm, since
> back around v4.12, mainline's qe.c grew a call to pvr_version_is which
> is ppc-only. So from that I sort of assumed that NXP had dropped trying
> to support the LS1021A even in their own kernels.
>
> In any case, we have zero interest in running an NXP kernel. Maybe I
> should clarify what I meant by "based on commits from" above: We're
> currently running a mainline 4.14 kernel on LS1021A, with a few patches
> inspired from the NXP 4.1 branch applied on top - but also with some
> manual fixes for e.g. the pvr_version_is() issue. Now we want to move
> that to a 4.19-based kernel (so that it aligns with our MPC8309 platform).

We also provide 4.19 based kernel in the codeaurora repo.  I think it
will be helpful to reuse patches there if you want to make your own
tree.

>
> >> This is just some first few steps, and I'm not claiming
> >> that this is sufficient to make the QE drivers build on ARM yet. But I
> >> have a customer with both mpc8309-based and ls1021a-based platforms, and
> >> they want to run the same, as-close-to-mainline-as-possible, kernel on
> >> both. So I will take a piecemeal approach, and try to make sure I don't
> >> break the ppc boards in the process (just building and booting one board
> >> is of course not sufficient, but better than nothing). Once I get to
> >> actually build some of the QE drivers for ARM, I'll of course also test
> >> them.
> >
> > Understood.  Zhao Qiang also maintains some patches similar to your
> > patchset and I think they are tested on ARM.  But the review of these
> > patches from last submission didn't finish.  It looks like your
> > patches are better divided but not really verified on ARM.  Zhao
> > Qiang's patches are tested but maybe need some final touch for
> > cleaning up.  I will let you guys decide what is the best approach to
> > make this upstreamed.
>
> Yes, as I said, I wanted to try a fresh approach since Zhao
> Qiang's patches seemed to be getting nowhere. Splitting the patches into
> smaller pieces is definitely part of that - for example, the completely
> trivial whitespace fix in patch 1 is to make sure the later coccinelle
> generated patch is precisely that (i.e., a later respin can just rerun
> the coccinelle script, with zero manual fixups). I also want to avoid
> mixing 

Re: [PATCH 0/7] towards QE support on ARM

[Rasmus Villemoes]

On 18/10/2019 23.52, Li Yang wrote:
> On Fri, Oct 18, 2019 at 3:54 PM Rasmus Villemoes
>  wrote:
>>
>> On 18/10/2019 22.16, Leo Li wrote:
>>>

 There have been several attempts in the past few years to allow building 
 the
 QUICC engine drivers for platforms other than PPC. This is (the beginning 
 of)
 yet another attempt. I hope I can get someone to pick up these relatively
 trivial patches (I _think_ they shouldn't change functionality at all), 
 and then
 I'll continue slowly working towards removing the PPC32 dependency for
 CONFIG_QUICC_ENGINE.
>>>
>>> Hi Rasmus,
>>>
>>> I don't fully understand the motivation of this work.  As far as I know the 
>>> QUICC ENGINE is only used on PowerPC based SoCs.
>>
>> Hm, you're not the Leo Li that participated in this thread
>> ?
> 
> Oops, I totally forgot about this discussion which is just three years
> ago.  :)  The QE-HDLC on LS1021a is kind of a special case.
> 
>>
>>
>>  Can you give an example on how is it used on ARM system?
>>
>> LS1021A, for example, which is the one I'm aiming for getting fully
>> supported in mainline.
>> 
>>
>> The forks at https://github.com/qoriq-open-source/linux.git have various
>> degrees of support (grep for commits saying stuff like "remove PPCisms"
>> - some versions can be found on
>> ). Our current kernel is
>> based on commits from the now-vanished 4.1 branch, and unfortunately at
>> least the 4.14 branch (LSDK-18.06-V4.14) trivially doesn't build on ARM,
>> despite the PPC32 dependency having been removed from CONFIG_QUICC_ENGINE.
> 
> Can you try the 4.14 branch from a newer LSDK release?  LS1021a should
> be supported platform on LSDK.  If it is broken, something is wrong.

What newer release? LSDK-18.06-V4.14 is the latest -V4.14 tag at
https://github.com/qoriq-open-source/linux.git, and identical to the
linux-4.14 branch. And despite commit 4c33e2d0576b removing the PPC32
dependency from QUICC_ENGINE, it clearly hasn't been built on arm, since
back around v4.12, mainline's qe.c grew a call to pvr_version_is which
is ppc-only. So from that I sort of assumed that NXP had dropped trying
to support the LS1021A even in their own kernels.

In any case, we have zero interest in running an NXP kernel. Maybe I
should clarify what I meant by "based on commits from" above: We're
currently running a mainline 4.14 kernel on LS1021A, with a few patches
inspired from the NXP 4.1 branch applied on top - but also with some
manual fixes for e.g. the pvr_version_is() issue. Now we want to move
that to a 4.19-based kernel (so that it aligns with our MPC8309 platform).

>> This is just some first few steps, and I'm not claiming
>> that this is sufficient to make the QE drivers build on ARM yet. But I
>> have a customer with both mpc8309-based and ls1021a-based platforms, and
>> they want to run the same, as-close-to-mainline-as-possible, kernel on
>> both. So I will take a piecemeal approach, and try to make sure I don't
>> break the ppc boards in the process (just building and booting one board
>> is of course not sufficient, but better than nothing). Once I get to
>> actually build some of the QE drivers for ARM, I'll of course also test
>> them.
> 
> Understood.  Zhao Qiang also maintains some patches similar to your
> patchset and I think they are tested on ARM.  But the review of these
> patches from last submission didn't finish.  It looks like your
> patches are better divided but not really verified on ARM.  Zhao
> Qiang's patches are tested but maybe need some final touch for
> cleaning up.  I will let you guys decide what is the best approach to
> make this upstreamed.

Yes, as I said, I wanted to try a fresh approach since Zhao
Qiang's patches seemed to be getting nowhere. Splitting the patches into
smaller pieces is definitely part of that - for example, the completely
trivial whitespace fix in patch 1 is to make sure the later coccinelle
generated patch is precisely that (i.e., a later respin can just rerun
the coccinelle script, with zero manual fixups). I also want to avoid
mixing the ppcism cleanups with other things (e.g. replacing some
of_get_property() by of_property_read_u32()). And the "testing on ARM"
part comes once I get to actually building on ARM. But there's not much
point doing all that unless there's some indication that this can be
applied to some tree that actually feeds into Linus', which is why I
started with a few trivial patches and precisely to start this discussion.

Rasmus

Re: [PATCH 0/7] towards QE support on ARM

[Li Yang]

On Fri, Oct 18, 2019 at 3:54 PM Rasmus Villemoes
 wrote:
>
> On 18/10/2019 22.16, Leo Li wrote:
> >
> >>
> >> There have been several attempts in the past few years to allow building 
> >> the
> >> QUICC engine drivers for platforms other than PPC. This is (the beginning 
> >> of)
> >> yet another attempt. I hope I can get someone to pick up these relatively
> >> trivial patches (I _think_ they shouldn't change functionality at all), 
> >> and then
> >> I'll continue slowly working towards removing the PPC32 dependency for
> >> CONFIG_QUICC_ENGINE.
> >
> > Hi Rasmus,
> >
> > I don't fully understand the motivation of this work.  As far as I know the 
> > QUICC ENGINE is only used on PowerPC based SoCs.
>
> Hm, you're not the Leo Li that participated in this thread
> ?

Oops, I totally forgot about this discussion which is just three years
ago.  :)  The QE-HDLC on LS1021a is kind of a special case.

>
>
>  Can you give an example on how is it used on ARM system?
>
> LS1021A, for example, which is the one I'm aiming for getting fully
> supported in mainline.
> 
>
> The forks at https://github.com/qoriq-open-source/linux.git have various
> degrees of support (grep for commits saying stuff like "remove PPCisms"
> - some versions can be found on
> ). Our current kernel is
> based on commits from the now-vanished 4.1 branch, and unfortunately at
> least the 4.14 branch (LSDK-18.06-V4.14) trivially doesn't build on ARM,
> despite the PPC32 dependency having been removed from CONFIG_QUICC_ENGINE.

Can you try the 4.14 branch from a newer LSDK release?  LS1021a should
be supported platform on LSDK.  If it is broken, something is wrong.

>
> >>
> >> Tested on an MPC8309-derived board.
> >
> > MPC8309 is also PPC based.
>
> True, of course. This is just some first few steps, and I'm not claiming
> that this is sufficient to make the QE drivers build on ARM yet. But I
> have a customer with both mpc8309-based and ls1021a-based platforms, and
> they want to run the same, as-close-to-mainline-as-possible, kernel on
> both. So I will take a piecemeal approach, and try to make sure I don't
> break the ppc boards in the process (just building and booting one board
> is of course not sufficient, but better than nothing). Once I get to
> actually build some of the QE drivers for ARM, I'll of course also test
> them.

Understood.  Zhao Qiang also maintains some patches similar to your
patchset and I think they are tested on ARM.  But the review of these
patches from last submission didn't finish.  It looks like your
patches are better divided but not really verified on ARM.  Zhao
Qiang's patches are tested but maybe need some final touch for
cleaning up.  I will let you guys decide what is the best approach to
make this upstreamed.

Regards,
Leo

Re: [PATCH 0/7] towards QE support on ARM

[Rasmus Villemoes]

On 18/10/2019 22.16, Leo Li wrote:
> 
>>
>> There have been several attempts in the past few years to allow building the
>> QUICC engine drivers for platforms other than PPC. This is (the beginning of)
>> yet another attempt. I hope I can get someone to pick up these relatively
>> trivial patches (I _think_ they shouldn't change functionality at all), and 
>> then
>> I'll continue slowly working towards removing the PPC32 dependency for
>> CONFIG_QUICC_ENGINE.
> 
> Hi Rasmus,
> 
> I don't fully understand the motivation of this work.  As far as I know the 
> QUICC ENGINE is only used on PowerPC based SoCs. 

Hm, you're not the Leo Li that participated in this thread
?


 Can you give an example on how is it used on ARM system?

LS1021A, for example, which is the one I'm aiming for getting fully
supported in mainline.


The forks at https://github.com/qoriq-open-source/linux.git have various
degrees of support (grep for commits saying stuff like "remove PPCisms"
- some versions can be found on
). Our current kernel is
based on commits from the now-vanished 4.1 branch, and unfortunately at
least the 4.14 branch (LSDK-18.06-V4.14) trivially doesn't build on ARM,
despite the PPC32 dependency having been removed from CONFIG_QUICC_ENGINE.

>>
>> Tested on an MPC8309-derived board.
> 
> MPC8309 is also PPC based.

True, of course. This is just some first few steps, and I'm not claiming
that this is sufficient to make the QE drivers build on ARM yet. But I
have a customer with both mpc8309-based and ls1021a-based platforms, and
they want to run the same, as-close-to-mainline-as-possible, kernel on
both. So I will take a piecemeal approach, and try to make sure I don't
break the ppc boards in the process (just building and booting one board
is of course not sufficient, but better than nothing). Once I get to
actually build some of the QE drivers for ARM, I'll of course also test
them.

Rasmus

RE: [PATCH 0/7] towards QE support on ARM

[Leo Li]

> -Original Message-
> From: Rasmus Villemoes 
> Sent: Friday, October 18, 2019 7:52 AM
> To: Qiang Zhao ; Leo Li ; Greg
> Kroah-Hartman ; Jiri Slaby
> ; Timur Tabi ; linuxppc-
> d...@lists.ozlabs.org; linux-arm-ker...@lists.infradead.org; linux-
> ker...@vger.kernel.org; linux-ser...@vger.kernel.org
> Cc: Rasmus Villemoes 
> Subject: [PATCH 0/7] towards QE support on ARM
> 
> There have been several attempts in the past few years to allow building the
> QUICC engine drivers for platforms other than PPC. This is (the beginning of)
> yet another attempt. I hope I can get someone to pick up these relatively
> trivial patches (I _think_ they shouldn't change functionality at all), and 
> then
> I'll continue slowly working towards removing the PPC32 dependency for
> CONFIG_QUICC_ENGINE.

Hi Rasmus,

I don't fully understand the motivation of this work.  As far as I know the 
QUICC ENGINE is only used on PowerPC based SoCs.  Can you give an example on 
how is it used on ARM system?

> 
> Tested on an MPC8309-derived board.

MPC8309 is also PPC based.

> 
> Rasmus Villemoes (7):
>   soc: fsl: qe: remove space-before-tab
>   soc: fsl: qe: drop volatile qualifier of struct qe_ic::regs
>   soc: fsl: qe: avoid ppc-specific io accessors
>   soc: fsl: qe: replace spin_event_timeout by readx_poll_timeout_atomic
>   serial: make SERIAL_QE depend on PPC32
>   serial: ucc_uart.c: explicitly include asm/cpm.h
>   soc/fsl/qe/qe.h: remove include of asm/cpm.h
> 
>  drivers/soc/fsl/qe/gpio.c | 30 
>  drivers/soc/fsl/qe/qe.c   | 44 +++
>  drivers/soc/fsl/qe/qe_ic.c|  8 ++---
>  drivers/soc/fsl/qe/qe_ic.h|  2 +-
>  drivers/soc/fsl/qe/qe_io.c| 40 ++---
>  drivers/soc/fsl/qe/qe_tdm.c   |  8 ++---
>  drivers/soc/fsl/qe/ucc.c  | 12 +++
>  drivers/soc/fsl/qe/ucc_fast.c | 66 ++-
>  drivers/soc/fsl/qe/ucc_slow.c | 38 ++--
>  drivers/soc/fsl/qe/usb.c  |  2 +-
>  drivers/tty/serial/Kconfig|  1 +
>  drivers/tty/serial/ucc_uart.c |  1 +
>  include/soc/fsl/qe/qe.h   |  1 -
>  13 files changed, 126 insertions(+), 127 deletions(-)
> 
> --
> 2.20.1

[PATCH 0/7] towards QE support on ARM

[Rasmus Villemoes]

There have been several attempts in the past few years to allow
building the QUICC engine drivers for platforms other than PPC. This
is (the beginning of) yet another attempt. I hope I can get someone to
pick up these relatively trivial patches (I _think_ they shouldn't
change functionality at all), and then I'll continue slowly working
towards removing the PPC32 dependency for CONFIG_QUICC_ENGINE.

Tested on an MPC8309-derived board.

Rasmus Villemoes (7):
  soc: fsl: qe: remove space-before-tab
  soc: fsl: qe: drop volatile qualifier of struct qe_ic::regs
  soc: fsl: qe: avoid ppc-specific io accessors
  soc: fsl: qe: replace spin_event_timeout by readx_poll_timeout_atomic
  serial: make SERIAL_QE depend on PPC32
  serial: ucc_uart.c: explicitly include asm/cpm.h
  soc/fsl/qe/qe.h: remove include of asm/cpm.h

 drivers/soc/fsl/qe/gpio.c | 30 
 drivers/soc/fsl/qe/qe.c   | 44 +++
 drivers/soc/fsl/qe/qe_ic.c|  8 ++---
 drivers/soc/fsl/qe/qe_ic.h|  2 +-
 drivers/soc/fsl/qe/qe_io.c| 40 ++---
 drivers/soc/fsl/qe/qe_tdm.c   |  8 ++---
 drivers/soc/fsl/qe/ucc.c  | 12 +++
 drivers/soc/fsl/qe/ucc_fast.c | 66 ++-
 drivers/soc/fsl/qe/ucc_slow.c | 38 ++--
 drivers/soc/fsl/qe/usb.c  |  2 +-
 drivers/tty/serial/Kconfig|  1 +
 drivers/tty/serial/ucc_uart.c |  1 +
 include/soc/fsl/qe/qe.h   |  1 -
 13 files changed, 126 insertions(+), 127 deletions(-)

-- 
2.20.1