Re: [PATCH v2 00/14] PCI: brcmstb: enable PCIe for STB chips

[Jim Quinlan]

On Fri, May 29, 2020 at 1:49 PM Rob Herring <robh@xxxxxxxxxx> wrote:
>
> On Tue, May 26, 2020 at 03:12:39PM -0400, Jim Quinlan wrote:
> > v2:
> > Commit: "device core: Add ability to handle multiple dma offsets"
> >   o Added helper func attach_dma_pfn_offset_map() in address.c (Chistoph)
> >   o Helpers funcs added to __phys_to_dma() & __dma_to_phys() (Christoph)
> >   o Added warning when multiple offsets are needed and !DMA_PFN_OFFSET_MAP
> >   o dev->dma_pfn_map => dev->dma_pfn_offset_map
> >   o s/frm/from/ for dma_pfn_offset_frm_{phys,dma}_addr() (Christoph)
> >   o In device.h: s/const void */const struct dma_pfn_offset_region */
> >   o removed 'unlikely' from unlikely(dev->dma_pfn_offset_map) since
> >     guarded by CONFIG_DMA_PFN_OFFSET_MAP (Christoph)
> >   o Since dev->dma_pfn_offset is copied in usb/core/{usb,message}.c, now
> >     dev->dma_pfn_offset_map is copied as well.
> >   o Merged two of the DMA commits into one (Christoph).
> >
> > Commit "arm: dma-mapping: Invoke dma offset func if needed":
> >   o Use helper functions instead of #if CONFIG_DMA_PFN_OFFSET
> >
> > Other commits' changes:
> >   o Removed need for carrying of_id var in priv (Nicolas)
> >   o Commit message rewordings (Bjorn)
> >   o Commit log messages filled to 75 chars (Bjorn)
> >   o devm_reset_control_get_shared())
> >     => devm_reset_control_get_optional_shared (Philipp)
> >   o Add call to reset_control_assert() in PCIe remove routines (Philipp)
> >
> > v1:
> > This patchset expands the usefulness of the Broadcom Settop Box PCIe
> > controller by building upon the PCIe driver used currently by the
> > Raspbery Pi.  Other forms of this patchset were submitted by me years
> > ago and not accepted; the major sticking point was the code required
> > for the DMA remapping needed for the PCIe driver to work [1].
> >
> > There have been many changes to the DMA and OF subsystems since that
> > time, making a cleaner and less intrusive patchset possible.  This
> > patchset implements a generalization of "dev->dma_pfn_offset", except
> > that instead of a single scalar offset it provides for multiple
> > offsets via a function which depends upon the "dma-ranges" property of
> > the PCIe host controller.  This is required for proper functionality
> > of the BrcmSTB PCIe controller and possibly some other devices.
>
> If you can enable the h/w support without the multiple offset support,
> then I'd split up this series. The latter part might take a bit more
> time.
>
> Rob
Unfortunately, the STB PCIe  controller depends on the multiple PFN
offset functionality.
Thanks,
Jim