Re: [PATCH v3 00/24] dmaengine: dw-edma: Add RP/EP local DMA controllers support

[Serge Semin <fancer.lancer@gmail.com>]

On Fri, Jun 10, 2022 at 12:14:35PM +0300, Serge Semin wrote:
> This is a final patchset 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: https://lore.kernel.org/linux-pci/20220610082535.12802-1-Sergey.Semin@baikalelectronics.ru/
> [2: In-progress v3] PCI: dwc: Add hw version and dma-ranges support
> Link: https://lore.kernel.org/linux-pci/20220610084444.14549-1-Sergey.Semin@baikalelectronics.ru/
> [3: In-progress v3] PCI: dwc: Add generic resources and Baikal-T1 support
> Link: https://lore.kernel.org/linux-pci/20220610085706.15741-1-Sergey.Semin@baikalelectronics.ru/
> [4: In-progress v3] dmaengine: dw-edma: Add RP/EP local DMA support
> Link: ---you are looking at it---
> 
> Note it is very recommended to merge the patchsets in the same order as
> they are listed in the set above in order to have them applied smoothly.
> Nothing prevents them from being reviewed synchronously though.
> 
> Please note originally this series was self content, but due to Frank
> being a bit faster in his work submission I had to rebase my patchset onto
> his one. So now this patchset turns to be dependent on the Frank' work:
> 
> Link: https://lore.kernel.org/linux-pci/20220524152159.2370739-1-Frank.Li@nxp.com/
> 
> So please merge Frank' series first before applying this one.
> 
> Here is a short summary regarding this patchset. The series starts with
> fixes patches. We discovered that the dw-edma-pcie.c driver incorrectly
> initializes the LL/DT base addresses for the platforms with not matching
> CPU and PCIe memory spaces. It is fixed by using the pci_bus_address()
> method to get a correct base address. After that you can find a series of
> the interleaved xfers fixes. It turned out the interleaved transfers
> implementation didn't work quite correctly from the very beginning for
> instance missing src/dst addresses initialization, etc. In the framework
> of the next two patches we suggest to add a new platform-specific
> callback - pci_address() and use it to convert the CPU address to the PCIe
> space address. It is at least required for the DW eDMA remote End-point
> setup on the platforms with not-matching CPU/PCIe address spaces. In case
> of the DW eDMA local RP/EP setup the conversion will be done automatically
> by the outbound iATU (if no DMA-bypass flag is specified for the
> corresponding iATU window). Then we introduce a set of the patches to make
> the DebugFS part of the code supporting the multi-eDMA controllers
> platforms. It starts with several cleanup patches and is closed joining
> the Read/Write channels into a single DMA-device as they originally should
> have been. After that you can find the patches with adding the non-atomic
> io-64 methods usage, dropping DT-region descriptors allocation, replacing
> chip IDs with the device name. In addition to that in order to have the
> eDMA embedded into the DW PCIe RP/EP supported we need to bypass the
> dma-ranges-based memory ranges mapping since in case of the root port DT
> node it's applicable for the peripheral PCIe devices only. Finally at the
> series closure we introduce a generic DW eDMA controller support being
> available in the DW PCIe Root Port/Endpoint driver.
> 
> Link: https://lore.kernel.org/linux-pci/20220324014836.19149-1-Sergey.Semin@baikalelectronics.ru/
> Changelog v2:
> - Drop the patches:
>   [PATCH 1/25] dmaengine: dw-edma: Drop dma_slave_config.direction field usage
>   [PATCH 2/25] dmaengine: dw-edma: Fix eDMA Rd/Wr-channels and DMA-direction semantics
>   since they are going to be merged in in the framework of the
>   Frank's patchset.
> - Add a new patch: "dmaengine: dw-edma: Release requested IRQs on
>   failure."
> - Drop __iomem qualifier from the struct dw_edma_debugfs_entry instance
>   definition in the dw_edma_debugfs_u32_get() method. (@Manivannan)
> - Add a new patch: "dmaengine: dw-edma: Rename DebugFS dentry variables to
>   'dent'." (@Manivannan)
> - Slightly extend the eDMA name array size. (@Manivannan)
> - Change the specific DMA mapping comment a bit to being
>   clearer. (@Manivannan)
> - Add a new patch: "PCI: dwc: Add generic iATU/eDMA CSRs space detection
>   method."
> - Don't fail eDMA detection procedure if the DW eDMA driver couldn't probe
>   device. That happens if the driver is disabled. (@Manivannan)
> - Add "dma" registers resource mapping procedure. (@Manivannan)
> - Move the eDMA CSRs space detection into the dw_pcie_map_detect() method.
> - Remove eDMA on the dw_pcie_ep_init() internal errors. (@Manivannan)
> - Remove eDMA in the dw_pcie_ep_exit() method.
> - Move the dw_pcie_edma_detect() method execution to the tail of the
>   dw_pcie_ep_init() function.
> 
> Link: https://lore.kernel.org/linux-pci/20220503225104.12108-1-Sergey.Semin@baikalelectronics.ru/
> Changelog v3:

> - Conditionally set dchan->dev->device.dma_coherent field since it can
>   be missing on some platforms. (@Manivannan)
> - Drop the patch: "PCI: dwc: Add generic iATU/eDMA CSRs space detection
>   method". A similar modification has been done in another patchset.
> - Add more comprehensive and less regression prune eDMA block detection
>   procedure.
> - Drop the patch: "dma-direct: take dma-ranges/offsets into account in
>   resource mapping". It will be separately reviewed.
> - Remove Manivannan tb tag from the modified patches.

@Mani, several patches have been changed. Could you have a look at the
series one more time?

-Sergey

> - Rebase onto the kernel v5.18.
> 
> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
> Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
> Cc: "Krzysztof Wilczyński" <kw@linux.com>
> Cc: linux-pci@vger.kernel.org
> Cc: dmaengine@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> 
> Serge Semin (24):
>   dmaengine: Fix dma_slave_config.dst_addr description
>   dmaengine: dw-edma: Release requested IRQs on failure
>   dmaengine: dw-edma: Convert ll/dt phys-address to PCIe bus/DMA address
>   dmaengine: dw-edma: Fix missing src/dst address of the interleaved
>     xfers
>   dmaengine: dw-edma: Don't permit non-inc interleaved xfers
>   dmaengine: dw-edma: Fix invalid interleaved xfers semantics
>   dmaengine: dw-edma: Add CPU to PCIe bus address translation
>   dmaengine: dw-edma: Add PCIe bus address getter to the remote EP
>     glue-driver
>   dmaengine: dw-edma: Drop chancnt initialization
>   dmaengine: dw-edma: Fix DebugFS reg entry type
>   dmaengine: dw-edma: Stop checking debugfs_create_*() return value
>   dmaengine: dw-edma: Add dw_edma prefix to the DebugFS nodes descriptor
>   dmaengine: dw-edma: Convert DebugFS descs to being kz-allocated
>   dmaengine: dw-edma: Rename DebugFS dentry variables to 'dent'
>   dmaengine: dw-edma: Simplify the DebugFS context CSRs init procedure
>   dmaengine: dw-edma: Move eDMA data pointer to DebugFS node descriptor
>   dmaengine: dw-edma: Join Write/Read channels into a single device
>   dmaengine: dw-edma: Use DMA-engine device DebugFS subdirectory
>   dmaengine: dw-edma: Use non-atomic io-64 methods
>   dmaengine: dw-edma: Drop DT-region allocation
>   dmaengine: dw-edma: Replace chip ID number with device name
>   dmaengine: dw-edma: Bypass dma-ranges mapping for the local setup
>   dmaengine: dw-edma: Skip cleanup procedure if no private data found
>   PCI: dwc: Add DW eDMA engine support
> 
>  drivers/dma/dw-edma/dw-edma-core.c            | 216 +++++-----
>  drivers/dma/dw-edma/dw-edma-core.h            |  10 +-
>  drivers/dma/dw-edma/dw-edma-pcie.c            |  24 +-
>  drivers/dma/dw-edma/dw-edma-v0-core.c         |  76 ++--
>  drivers/dma/dw-edma/dw-edma-v0-core.h         |   1 -
>  drivers/dma/dw-edma/dw-edma-v0-debugfs.c      | 372 ++++++++----------
>  drivers/dma/dw-edma/dw-edma-v0-debugfs.h      |   5 -
>  .../pci/controller/dwc/pcie-designware-ep.c   |  12 +-
>  .../pci/controller/dwc/pcie-designware-host.c |  13 +-
>  drivers/pci/controller/dwc/pcie-designware.c  | 186 +++++++++
>  drivers/pci/controller/dwc/pcie-designware.h  |  20 +
>  include/linux/dma/edma.h                      |  18 +-
>  include/linux/dmaengine.h                     |   2 +-
>  13 files changed, 589 insertions(+), 366 deletions(-)
> 
> -- 
> 2.35.1
>