mbox series

[v3,0/6] MIPS: ralink: fix PCI IO resources

Message ID 20210925203224.10419-1-sergio.paracuellos@gmail.com (mailing list archive)
Headers show
Series MIPS: ralink: fix PCI IO resources | expand

Message

Sergio Paracuellos Sept. 25, 2021, 8:32 p.m. UTC
MIPs ralink need a special tratement regarding the way it handles PCI IO
resources. On MIPS I/O ports are memory mapped, so we access them using normal
load/store instructions. MIPS 'plat_mem_setup()' function does a call to
'set_io_port_base(KSEG1)'. There, variable 'mips_io_port_base'
is set then using this address which is a virtual address to which all
ports are being mapped. Ralink I/O space has a mapping of bus address
equal to the window into the mmio space, with an offset of IO start range
cpu address. This means that to have this working we need:
- linux port numbers in the range 0-0xffff.
- pci port numbers in the range 0-0xffff.
- io_offset being zero.

These means at the end to have bus address 0 mapped to IO range cpu address.
We need a way of properly set 'mips_io_port_base' with a virtually mapped
value of the IO cpu address.

This series do the following approach:
1) Revert two bad commit from a previous attempt of make this work [0].
2) Set PCI_IOBASE to mips 'mips_io_port_base'.
3) Allow architecture dependent 'pci_remap_iospace'.
4) Implement 'pci_remap_iospace' for MIPS.
5) Be sure IOBASE address for IO window is set with correct value.

More context about this series appoach in this mail thread [1].

Patches related with reverts are from this merge cycle so they are only
added to the staging git tree. So to have all stuff together I'd like to
get everybody Ack's to get all of this series through staging tree if
possible :).

Thanks in advance for your time.

Changes in v3:
 - Collect Arnd's Acked-by for the patches. 
 - Be sure IO resource start address is zero and WARN_ONCE if it is not
   on MIPS pci_remap_iospace() patch. Also make use of 'resource_size'
   instead of do the logic explicitly again.

Changes in v2:
 - re-do commit messages for PCI patch as Bjorn pointed out in previous series.
 - Add Bjorn's Acked-by for PCI subsystem patch.
 - Re-do commit message of MIPS 'pci_remap_iospace()' patch to align with changes
   in the PCI patch (s/architecture dependent/architecture-specific/)
 - Add Fixes-by tag for MIPS set PCI_IOBASE patch.

[0]: https://www.spinics.net/lists/kernel/msg4051474.html
[1]: https://lkml.org/lkml/2021/9/22/6
Sergio Paracuellos (6):
  Revert "MIPS: ralink: don't define PC_IOBASE but increase
    IO_SPACE_LIMIT"
  Revert "staging: mt7621-pci: set end limit for 'ioport_resource'"
  MIPS: ralink: set PCI_IOBASE to 'mips_io_port_base'
  PCI: Allow architecture-specific pci_remap_iospace()
  MIPS: implement architecture-specific 'pci_remap_iospace()'
  staging: mt7621-pci: properly adjust base address for the IO window

 arch/mips/include/asm/mach-ralink/spaces.h |  4 +++-
 arch/mips/include/asm/pci.h                |  2 ++
 arch/mips/pci/pci-generic.c                | 14 ++++++++++++++
 drivers/pci/pci.c                          |  2 ++
 drivers/staging/mt7621-pci/pci-mt7621.c    |  4 +---
 5 files changed, 22 insertions(+), 4 deletions(-)

Comments

Arnd Bergmann Sept. 27, 2021, 7:51 a.m. UTC | #1
On Sat, Sep 25, 2021 at 10:33 PM Sergio Paracuellos
<sergio.paracuellos@gmail.com> wrote:
>
> Patches related with reverts are from this merge cycle so they are only
> added to the staging git tree. So to have all stuff together I'd like to
> get everybody Ack's to get all of this series through staging tree if
> possible :).
>
> Thanks in advance for your time.

Looks all good to me now, just one general remark: Try to give a little more
time between respinning the entire series, otherwise you get the opposite
effect and reviewers start ignoring your emails after getting annoyed at the
number of emails. Once you are reasonably sure that no more comments are
coming in, or you have made substantial changes, it's time to resend the
series.

        Arnd
Sergio Paracuellos Sept. 27, 2021, 9:14 a.m. UTC | #2
Hi Arnd,

On Mon, Sep 27, 2021 at 9:51 AM Arnd Bergmann <arnd@arndb.de> wrote:
>
> On Sat, Sep 25, 2021 at 10:33 PM Sergio Paracuellos
> <sergio.paracuellos@gmail.com> wrote:
> >
> > Patches related with reverts are from this merge cycle so they are only
> > added to the staging git tree. So to have all stuff together I'd like to
> > get everybody Ack's to get all of this series through staging tree if
> > possible :).
> >
> > Thanks in advance for your time.
>
> Looks all good to me now, just one general remark: Try to give a little more
> time between respinning the entire series, otherwise you get the opposite
> effect and reviewers start ignoring your emails after getting annoyed at the
> number of emails. Once you are reasonably sure that no more comments are
> coming in, or you have made substantial changes, it's time to resend the
> series.

Thanks for reviewing this and also for the advice. Will take it into
account from now on.

>
>         Arnd

Best regards,
    Sergio Paracuellos
Sergio Paracuellos Oct. 3, 2021, 4:21 p.m. UTC | #3
Hi Greg,

On Sat, Sep 25, 2021 at 10:32 PM Sergio Paracuellos
<sergio.paracuellos@gmail.com> wrote:
>
> MIPs ralink need a special tratement regarding the way it handles PCI IO
> resources. On MIPS I/O ports are memory mapped, so we access them using normal
> load/store instructions. MIPS 'plat_mem_setup()' function does a call to
> 'set_io_port_base(KSEG1)'. There, variable 'mips_io_port_base'
> is set then using this address which is a virtual address to which all
> ports are being mapped. Ralink I/O space has a mapping of bus address
> equal to the window into the mmio space, with an offset of IO start range
> cpu address. This means that to have this working we need:
> - linux port numbers in the range 0-0xffff.
> - pci port numbers in the range 0-0xffff.
> - io_offset being zero.
>
> These means at the end to have bus address 0 mapped to IO range cpu address.
> We need a way of properly set 'mips_io_port_base' with a virtually mapped
> value of the IO cpu address.
>
> This series do the following approach:
> 1) Revert two bad commit from a previous attempt of make this work [0].
> 2) Set PCI_IOBASE to mips 'mips_io_port_base'.
> 3) Allow architecture dependent 'pci_remap_iospace'.
> 4) Implement 'pci_remap_iospace' for MIPS.
> 5) Be sure IOBASE address for IO window is set with correct value.
>
> More context about this series appoach in this mail thread [1].
>
> Patches related with reverts are from this merge cycle so they are only
> added to the staging git tree. So to have all stuff together I'd like to
> get everybody Ack's to get all of this series through staging tree if
> possible :).
>
> Thanks in advance for your time.
>
> Changes in v3:
>  - Collect Arnd's Acked-by for the patches.
>  - Be sure IO resource start address is zero and WARN_ONCE if it is not
>    on MIPS pci_remap_iospace() patch. Also make use of 'resource_size'
>    instead of do the logic explicitly again.

I think nothing is missing to get this added through the staging tree.

Thanks in advance for your time.

Best regards,
   Sergio Paracuellos

>
> Changes in v2:
>  - re-do commit messages for PCI patch as Bjorn pointed out in previous series.
>  - Add Bjorn's Acked-by for PCI subsystem patch.
>  - Re-do commit message of MIPS 'pci_remap_iospace()' patch to align with changes
>    in the PCI patch (s/architecture dependent/architecture-specific/)
>  - Add Fixes-by tag for MIPS set PCI_IOBASE patch.
>
> [0]: https://www.spinics.net/lists/kernel/msg4051474.html
> [1]: https://lkml.org/lkml/2021/9/22/6
> Sergio Paracuellos (6):
>   Revert "MIPS: ralink: don't define PC_IOBASE but increase
>     IO_SPACE_LIMIT"
>   Revert "staging: mt7621-pci: set end limit for 'ioport_resource'"
>   MIPS: ralink: set PCI_IOBASE to 'mips_io_port_base'
>   PCI: Allow architecture-specific pci_remap_iospace()
>   MIPS: implement architecture-specific 'pci_remap_iospace()'
>   staging: mt7621-pci: properly adjust base address for the IO window
>
>  arch/mips/include/asm/mach-ralink/spaces.h |  4 +++-
>  arch/mips/include/asm/pci.h                |  2 ++
>  arch/mips/pci/pci-generic.c                | 14 ++++++++++++++
>  drivers/pci/pci.c                          |  2 ++
>  drivers/staging/mt7621-pci/pci-mt7621.c    |  4 +---
>  5 files changed, 22 insertions(+), 4 deletions(-)
>
> --
> 2.25.1
>
Greg KH Oct. 5, 2021, 10:36 a.m. UTC | #4
On Sun, Oct 03, 2021 at 06:21:21PM +0200, Sergio Paracuellos wrote:
> Hi Greg,
> 
> On Sat, Sep 25, 2021 at 10:32 PM Sergio Paracuellos
> <sergio.paracuellos@gmail.com> wrote:
> >
> > MIPs ralink need a special tratement regarding the way it handles PCI IO
> > resources. On MIPS I/O ports are memory mapped, so we access them using normal
> > load/store instructions. MIPS 'plat_mem_setup()' function does a call to
> > 'set_io_port_base(KSEG1)'. There, variable 'mips_io_port_base'
> > is set then using this address which is a virtual address to which all
> > ports are being mapped. Ralink I/O space has a mapping of bus address
> > equal to the window into the mmio space, with an offset of IO start range
> > cpu address. This means that to have this working we need:
> > - linux port numbers in the range 0-0xffff.
> > - pci port numbers in the range 0-0xffff.
> > - io_offset being zero.
> >
> > These means at the end to have bus address 0 mapped to IO range cpu address.
> > We need a way of properly set 'mips_io_port_base' with a virtually mapped
> > value of the IO cpu address.
> >
> > This series do the following approach:
> > 1) Revert two bad commit from a previous attempt of make this work [0].
> > 2) Set PCI_IOBASE to mips 'mips_io_port_base'.
> > 3) Allow architecture dependent 'pci_remap_iospace'.
> > 4) Implement 'pci_remap_iospace' for MIPS.
> > 5) Be sure IOBASE address for IO window is set with correct value.
> >
> > More context about this series appoach in this mail thread [1].
> >
> > Patches related with reverts are from this merge cycle so they are only
> > added to the staging git tree. So to have all stuff together I'd like to
> > get everybody Ack's to get all of this series through staging tree if
> > possible :).
> >
> > Thanks in advance for your time.
> >
> > Changes in v3:
> >  - Collect Arnd's Acked-by for the patches.
> >  - Be sure IO resource start address is zero and WARN_ONCE if it is not
> >    on MIPS pci_remap_iospace() patch. Also make use of 'resource_size'
> >    instead of do the logic explicitly again.
> 
> I think nothing is missing to get this added through the staging tree.

Great, thanks for sticking with this, will go queue it up now.

greg k-h
Sergio Paracuellos Oct. 5, 2021, 10:51 a.m. UTC | #5
On Tue, Oct 5, 2021 at 12:36 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sun, Oct 03, 2021 at 06:21:21PM +0200, Sergio Paracuellos wrote:
> > Hi Greg,
> >
> > On Sat, Sep 25, 2021 at 10:32 PM Sergio Paracuellos
> > <sergio.paracuellos@gmail.com> wrote:
> > >
> > > MIPs ralink need a special tratement regarding the way it handles PCI IO
> > > resources. On MIPS I/O ports are memory mapped, so we access them using normal
> > > load/store instructions. MIPS 'plat_mem_setup()' function does a call to
> > > 'set_io_port_base(KSEG1)'. There, variable 'mips_io_port_base'
> > > is set then using this address which is a virtual address to which all
> > > ports are being mapped. Ralink I/O space has a mapping of bus address
> > > equal to the window into the mmio space, with an offset of IO start range
> > > cpu address. This means that to have this working we need:
> > > - linux port numbers in the range 0-0xffff.
> > > - pci port numbers in the range 0-0xffff.
> > > - io_offset being zero.
> > >
> > > These means at the end to have bus address 0 mapped to IO range cpu address.
> > > We need a way of properly set 'mips_io_port_base' with a virtually mapped
> > > value of the IO cpu address.
> > >
> > > This series do the following approach:
> > > 1) Revert two bad commit from a previous attempt of make this work [0].
> > > 2) Set PCI_IOBASE to mips 'mips_io_port_base'.
> > > 3) Allow architecture dependent 'pci_remap_iospace'.
> > > 4) Implement 'pci_remap_iospace' for MIPS.
> > > 5) Be sure IOBASE address for IO window is set with correct value.
> > >
> > > More context about this series appoach in this mail thread [1].
> > >
> > > Patches related with reverts are from this merge cycle so they are only
> > > added to the staging git tree. So to have all stuff together I'd like to
> > > get everybody Ack's to get all of this series through staging tree if
> > > possible :).
> > >
> > > Thanks in advance for your time.
> > >
> > > Changes in v3:
> > >  - Collect Arnd's Acked-by for the patches.
> > >  - Be sure IO resource start address is zero and WARN_ONCE if it is not
> > >    on MIPS pci_remap_iospace() patch. Also make use of 'resource_size'
> > >    instead of do the logic explicitly again.
> >
> > I think nothing is missing to get this added through the staging tree.
>
> Great, thanks for sticking with this, will go queue it up now.

Thanks!

Best regards,
    Sergio Paracuellos

>
> greg k-h