[PATCH v2 0/8] Add Keystone PCIe controller driver

[Jingoo Han]

On Saturday, June 21, 2014 12:31 AM, Murali Karicheri wrote:
> On 6/17/2014 8:08 PM, Bjorn Helgaas wrote:
> > On Tue, Jun 10, 2014 at 02:51:19PM -0400, Murali Karicheri wrote:
> >> This patch adds a PCIe controller driver for Keystone SoCs. This
> >> is based on v1 of the series posted to the mailing list.
> >>
> >> CC: Santosh Shilimkar <santosh.shilimkar at ti.com>
> >> CC: Russell King <linux at arm.linux.org.uk>
> >> CC: Grant Likely <grant.likely at linaro.org>
> >> CC: Rob Herring <robh+dt at kernel.org>
> >> CC: Mohit Kumar <mohit.kumar at st.com>
> >> CC: Jingoo Han <jg1.han at samsung.com>
> >> CC: Bjorn Helgaas <bhelgaas at google.com>
> >> CC: Pratyush Anand <pratyush.anand at st.com>
> >> CC: Richard Zhu <r65037 at freescale.com>
> >> CC: Kishon Vijay Abraham I <kishon at ti.com>
> >> CC: Marek Vasut <marex at denx.de>
> >> CC: Arnd Bergmann <arnd at arndb.de>
> >> CC: Pawel Moll <pawel.moll at arm.com>
> >> CC: Mark Rutland <mark.rutland at arm.com>
> >> CC: Ian Campbell <ijc+devicetree at hellion.org.uk>
> >> CC: Kumar Gala <galak at codeaurora.org>
> >> CC: Randy Dunlap <rdunlap at infradead.org>
> >> CC: Grant Likely <grant.likely at linaro.org>
> >>
> >>
> >> Changelog:
> >>
> >> V2
> >>   - Split the designware pcie enhancement patch to multiple
> >>     patches based on functionality added
> >>   - Remove the quirk code and add a patch to fix mps/mrss
> >>     tuning for ARM. Use kernel command line parameter
> >>     pci=pcie_bus_perf to work with Keystone PCI Controller.
> >>     Following patch addressed this.
> >>       [PATCH v1] ARM: pci: add call to pcie_bus_configure_settings()
> >>   - Add documentation for device tree bindings
> >>   - Add separate interrupt controller nodes for MSI and Legacy
> >>     IRQs and use irq map for legacy IRQ
> >>   - Use compatibility to identify v3.65 version of the DW hardware
> >>     and use it to customize the designware common code.
> >>   - Use reg property for configuration space instead of range
> >>   - Other minor updates based on code inspection.
> >>
> >> V1
> >>   - Add an interrupt controller node for Legacy irq chip and use
> >>     interrupt map/map-mask property to map legacy IRQs A/B/C/D
> >>   - Add a Phy driver to replace the original serdes driver
> >>   - Move common application register handling code to a separate
> >>     file to allow re-use across other platforms that use older
> >>     DW PCIe h/w
> >>   - PCI quirk for maximum read request size. Check and override only
> >>     if the maximum is higher than what controller can handle.
> >>   - Converted to a module platform driver.
> >>
> >>
> >> Murali Karicheri (8):
> >>    PCI: designware: add rd[wr]_other_conf API
> >>    PCI: designware: refactor host init code to re-use on v3.65 DW pci hw
> >>    PCI: designware: update pcie core driver to work with dw hw version
> >>      3.65
> >>    PCI: designware: add msi controller functions for v3.65 hw
> >>    PCI: designware: add PCI controller functions for v3.65 DW hw
> >>    phy: Add serdes phy driver for keystone
> >>    PCI: keystone: add pcie driver based on designware core driver
> >>    ARM: keystone: add pcie related options
> >>
> >>   .../devicetree/bindings/pci/designware-pcie.txt    |   42 ++
> >>   .../devicetree/bindings/pci/pci-keystone.txt       |   56 +++
> >>   .../bindings/phy/phy-keystone-serdes.txt           |   25 ++
> >>   arch/arm/mach-keystone/Kconfig                     |    1 +
> >>   drivers/pci/host/Kconfig                           |   12 +
> >>   drivers/pci/host/Makefile                          |    2 +
> >>   drivers/pci/host/pci-dw-v3_65-msi.c                |  149 +++++++
> >>   drivers/pci/host/pci-dw-v3_65.c                    |  390 ++++++++++++++++++
> >>   drivers/pci/host/pci-dw-v3_65.h                    |   34 ++
> >>   drivers/pci/host/pci-keystone.c                    |  418 ++++++++++++++++++++
> >>   drivers/pci/host/pcie-designware.c                 |  175 +++++---
> >>   drivers/pci/host/pcie-designware.h                 |   42 +-
> >>   drivers/phy/Kconfig                                |    6 +
> >>   drivers/phy/Makefile                               |    1 +
> >>   drivers/phy/phy-keystone-serdes.c                  |  230 +++++++++++
> >>   15 files changed, 1531 insertions(+), 52 deletions(-)
> >>   create mode 100644 Documentation/devicetree/bindings/pci/pci-keystone.txt
> >>   create mode 100644 Documentation/devicetree/bindings/phy/phy-keystone-serdes.txt
> >>   create mode 100644 drivers/pci/host/pci-dw-v3_65-msi.c
> >>   create mode 100644 drivers/pci/host/pci-dw-v3_65.c
> >>   create mode 100644 drivers/pci/host/pci-dw-v3_65.h
> >>   create mode 100644 drivers/pci/host/pci-keystone.c
> >>   create mode 100644 drivers/phy/phy-keystone-serdes.c
> > I'm not willing to merge phy-keystone-serdes.c because I don't
> > maintain drivers/phy and because of the binary blob of register values
> > it contains, but maybe somebody else will.  I assume it could be
> > merged by itself before the rest of this.
> >
> > I'm looking for acks from Mohit and/or Jingoo for the pci/host
> > changes, and from Arnd for the devicetree/bindings changes.
> >
> > Adding these "-dw-3_64" files is sort of ugly.  If that code is only
> > used by keystone, maybe it could just be moved to pci-keystone.c?  But
> > I'll defer to Mohit and Jingoo on that and the way you modify
> > pcie-designware.c.
> >
> > Bjorn
> Bjorn, Jingoo,
> 
> Unfortunately I lost Jingoo's email from my Inbox. So I cut-n-paste the
> comment from
> internet and respond.
> 
> Jingoo Han wrote:-
> =============================================================================
> I think so, too.
> 
> DT maintainers and arch maintainers should review the following
> dt bindings.
>    .../devicetree/bindings/pci/designware-pcie.txt    |   42 ++
>    .../devicetree/bindings/pci/pci-keystone.txt       |   56 +++
> Generic PHY maintainer (Kishon Vijay Abraham I) should review the
> following phy driver.
>    drivers/phy/phy-keystone-serdes.c
> 
>  >
>  > I'm looking for acks from Mohit and/or Jingoo for the pci/host
>  > changes, and from Arnd for the devicetree/bindings changes.
>  >
>  > Adding these "-dw-3_64" files is sort of ugly.  If that code is only
>  > used by keystone, maybe it could just be moved to pci-keystone.c?  But
>  > I'll defer to Mohit and Jingoo on that and the way you modify
>  > pcie-designware.c.
> 
> I agree with Bjorn Helgaas's opinion. These three "-dw-3_64" files
> look terrible! I don't have a good way to handle this; however,
> moving this code to pci-keystone.c looks better.
> ======================================================================
> 
> The original RFC I had submitted had all of the application space register
> handling code as part of the Keystone PCI driver. As per Arnd's comment
> (See
> my change log against v1), the code was moved to a separate file so that
> the next driver that has same version of the DW hw could re-use this code.
> I agree with Arnd and moved the code to v_3_65 specific files.  What is
> your proposal?  Do you have objection to the file name? or it's content?

I said utterly that "I agree with Bjorn Helgaas's opinion". Also, Bjorn
said that "Adding these "-dw-3_64" files is sort of ugly".
Thus, the point is the file name, not the content, as Santosh Shilimkar
said.

> 
> If objection is on the file name,  please suggest alternate names. If you
> are okay with the file name, and doesn't like the code, it will be helpful
> to review the code and provide specific comments against the patch itself
> so that I can address the same.

I say again that "I have no idea about the alternate file names".
However, if you want to add v_3_65 specific files, please don't
split the files. Please make these three files as 1 file.

   drivers/pci/host/pci-dw-v3_65-msi.c
   drivers/pci/host/pci-dw-v3_65.c
   drivers/pci/host/pci-dw-v3_65.h
   --> drivers/pci/host/pci-dw-v3-65.c
        (I don't have no idea about the name)

Best regards,
Jingoo Han

> 
> Murali