Re: [PATCH v4 00/18] PCI: dwc: Various fixes and cleanups

[Bjorn Helgaas]

On Fri, Jun 10, 2022 at 11:25:16AM +0300, Serge Semin wrote:
> This patchset is a first one in the series created in the framework of
> my Baikal-T1 PCIe/eDMA-related work:
> 
> [1: In-progress v4] PCI: dwc: Various fixes and cleanups
> Link: ---you are looking at it---
> [2: In-progress v2] PCI: dwc: Add hw version and dma-ranges support
> Link: https://lore.kernel.org/linux-pci/20220503214638.1895-1-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx/
> [3: In-progress v2] PCI: dwc: Add extended YAML-schema and Baikal-T1 support
> Link: https://lore.kernel.org/linux-pci/20220503214638.1895-1-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx/
> [4: In-progress v2] dmaengine: dw-edma: Add RP/EP local DMA support
> Link: https://lore.kernel.org/linux-pci/20220503225104.12108-1-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx/
> 
> Note it is very recommended to merge the patchsets in the same order as
> they are placed in the list above in order to prevent possible merge
> conflicts. Nothing prevents them from being reviewed synchronously though.
> Any tests are very welcome!
> 
> As it can be easily inferred from the patchset title, this series is about
> the DW PCIe Root Port/Endpoint driver fixes and the code cleanups, where
> fixes come before the cleanup patches. The patchset starts with adding the
> stop_link() platform-specific method invocation in case of the PCIe host
> probe procedure errors. It has been missing in the cleanup-on-error path
> of the DW PCIe Host initialization method. After that the unrolled CSRs
> layout is added to the iATU disable procedure. In third the disable iATU
> procedure is fixed to be called only for the internal ATU as being
> specific for the internal ATU implementation. Then the outbound iATU
> extended region setup procedure is fixed to have the INCREASE_REGION_SIZE
> flag set based on the limit-address - not the region size one. The last
> but not least the CDM-check enabling procedure is fixed to be independent
> from the non-related num_lanes field state.
> 
> Afterwards there is a series of cleanups. It concerns the changes like
> adding braces to the multi-line if-else constructions, trailing new-lines
> to the print format-string, dropping unnecessary version checking, and
> various code simplifications and optimizations.
> 
> New features like adding two-level DT bindings abstraction, adding better
> structured IP-core version interface, adding iATU regions size detection
> and the PCIe regions verification procedure, adding dma-ranges support,
> introducing a set of generic platform clocks and resets and finally adding
> Baikal-T1 PCIe interface support will be submitted in the next part of the
> series.
> 
> Link: https://lore.kernel.org/linux-pci/20220324012524.16784-1-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx/
> Changelog v2:
> - Fix the end address of the example in the patch log with
>   the INCREASE_REGION_SIZE flag usage fixup. It should be
>   0x1000FFFF and not 0x0000FFFF (@Manivannan).
> - Add the cleanup-on-error path to the dw_pcie_ep_init() function.
>   (@Manivannan)
> 
> Link: https://lore.kernel.org/linux-pci/20220503212300.30105-1-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx/
> Changelog v3:
> - Convert region variable type to u32 in order to fix the implicit type
>   conversion peculiarity. (@kbot)
> - Rebase onto v5.18-rc6.
> 
> Link: https://lore.kernel.org/linux-pci/20220517125058.18488-1-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx/
> Changelog v4:
> - Move the patch "PCI: dwc: Deallocate EPC memory on EP init error" to
>   being applied before the cleanup patches.
> - Add a new fixes patch: "PCI: dwc: Enable CDM-check independently from
>   the num_lanes value".
> - Add a new cleanup patch: "PCI: dwc: Organize local variables usage".
> - Add a new cleanup patch: "PCI: dwc: Re-use local pointer to the
>   resource data".
> - Add a new cleanup patch: "PCI: dwc: Add start_link/stop_link inliners".
> - Add a new cleanup patch: "PCI: dwc: Move io_cfg_atu_shared to the Root
>   Port descriptor".
> - Add a new cleanup patch: "PCI: dwc: Add dw_ prefix to the pcie_port
>   structure name".
> - Drop the patch "PCI: dwc: Don't use generic IO-ops for DBI-space
>   access". (@Rob)
> - Drop Manivannan tested tag from the changed patches.
> - Rebase onto v5.18.
> 
> Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
> Cc: Alexey Malahov <Alexey.Malahov@xxxxxxxxxxxxxxxxxxxx>
> Cc: Pavel Parkhomenko <Pavel.Parkhomenko@xxxxxxxxxxxxxxxxxxxx>
> Cc: Jingoo Han <jingoohan1@xxxxxxxxx>
> Cc: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>
> Cc: "Krzysztof Wilczyński" <kw@xxxxxxxxx>
> Cc: Frank Li <Frank.Li@xxxxxxx>
> Cc: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> Cc: linux-pci@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> 
> Serge Semin (18):
>   PCI: dwc: Stop link in the host init error and de-initialization
>   PCI: dwc: Add unroll iATU space support to the regions disable method
>   PCI: dwc: Disable outbound windows for controllers with iATU
>   PCI: dwc: Set INCREASE_REGION_SIZE flag based on limit address
>   PCI: dwc: Deallocate EPC memory on EP init error
>   PCI: dwc: Enable CDM-check independently from the num_lanes value
>   PCI: dwc: Add braces to the multi-line if-else statements
>   PCI: dwc: Add trailing new-line literals to the log messages
>   PCI: dwc: Discard IP-core version checking on unrolled iATU detection
>   PCI: dwc: Convert Link-up status method to using dw_pcie_readl_dbi()
>   PCI: dwc: Organize local variables usage
>   PCI: dwc: Re-use local pointer to the resource data
>   PCI: dwc: Add start_link/stop_link inliners
>   PCI: dwc: Move io_cfg_atu_shared to the Root Port descriptor
>   PCI: dwc: Add dw_ prefix to the pcie_port structure name
>   PCI: dwc-plat: Simplify the probe method return value handling
>   PCI: dwc-plat: Discard unused regmap pointer
>   PCI: dwc-plat: Drop dw_plat_pcie_of_match forward declaration
> 
>  drivers/pci/controller/dwc/pci-dra7xx.c       |  12 +-
>  drivers/pci/controller/dwc/pci-exynos.c       |   6 +-
>  drivers/pci/controller/dwc/pci-imx6.c         |   6 +-
>  drivers/pci/controller/dwc/pci-keystone.c     |  20 ++--
>  .../pci/controller/dwc/pci-layerscape-ep.c    |  12 --
>  drivers/pci/controller/dwc/pci-layerscape.c   |   2 +-
>  drivers/pci/controller/dwc/pci-meson.c        |   2 +-
>  drivers/pci/controller/dwc/pcie-al.c          |   6 +-
>  drivers/pci/controller/dwc/pcie-armada8k.c    |   4 +-
>  drivers/pci/controller/dwc/pcie-artpec6.c     |   4 +-
>  .../pci/controller/dwc/pcie-designware-ep.c   |  30 +++--
>  .../pci/controller/dwc/pcie-designware-host.c | 104 ++++++++++--------
>  .../pci/controller/dwc/pcie-designware-plat.c |  25 +----
>  drivers/pci/controller/dwc/pcie-designware.c  |  72 +++++++-----
>  drivers/pci/controller/dwc/pcie-designware.h  |  46 +++++---
>  drivers/pci/controller/dwc/pcie-dw-rockchip.c |   4 +-
>  drivers/pci/controller/dwc/pcie-fu740.c       |   2 +-
>  drivers/pci/controller/dwc/pcie-histb.c       |  10 +-
>  drivers/pci/controller/dwc/pcie-intel-gw.c    |   6 +-
>  drivers/pci/controller/dwc/pcie-keembay.c     |   4 +-
>  drivers/pci/controller/dwc/pcie-kirin.c       |   2 +-
>  drivers/pci/controller/dwc/pcie-qcom.c        |   4 +-
>  drivers/pci/controller/dwc/pcie-spear13xx.c   |   6 +-
>  drivers/pci/controller/dwc/pcie-tegra194.c    |  22 ++--
>  drivers/pci/controller/dwc/pcie-uniphier.c    |  10 +-
>  drivers/pci/controller/dwc/pcie-visconti.c    |   6 +-
>  26 files changed, 225 insertions(+), 202 deletions(-)

This doesn't apply cleanly on v5.19-rc1 (my "main" branch).  v5.19-rc1
was tagged June 5, but apparently v4 was rebased to v5.18 and posted
June 10?  That's just a non-starter because many of these files were
changed during the merge window between v5.18 and v5.19-rc1.

I'll be looking for an ack from Jingoo and/or Gustavo, maintainers of
pcie-designware.c and related files.

Generally I wait for owners of files to comment before I review in
detail.  This is just expedient because they know the code better than
I do and can resolve lots of things in parallel before getting
single-threaded on me or Lorenzo.

Bjorn