Re: [PATCH v4 02/18] PCI: dwc: Add unroll iATU space support to the regions disable method

[Rob Herring <robh@kernel.org>]

On Fri, Jun 10, 2022 at 11:25:18AM +0300, Serge Semin wrote:
> The dw_pcie_disable_atu() method was introduced in the commit f8aed6ec624f
> ("PCI: dwc: designware: Add EP mode support"). Since then it hasn't
> changed at all.  For all that time the method has supported the viewport
> version of the iATU CSRs only. Basically it works for the DW PCIe IP-cores
> older than v4.80a since the newer controllers are equipped with the
> unrolled iATU/eDMA space. It means the methods using it like
> pci_epc_ops.clear_bar and pci_epc_ops.unmap_addr callbacks just don't work
> correctly for the DW PCIe controllers with unrolled iATU CSRs. The same
> concerns the dw_pcie_setup_rc() method, which disables the outbound iATU
> entries before re-initializing them.
> 
> So in order to fix the problems denoted above let's convert the
> dw_pcie_disable_atu() method to disabling the iATU inbound and outbound
> regions in the unrolled iATU CSRs in case the DW PCIe controller has been
> synthesized with the ones support. The former semantics will be remained
> for the controller having iATU mapped over the viewport.
> 
> Fixes: f8aed6ec624f ("PCI: dwc: designware: Add EP mode support")
> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> 
> ---
> 
> Changelog v3:
> - Convert region variable type to u32 in order to fix the implicit type
>   conversion peculiarity. (@kbot)
> ---
>  drivers/pci/controller/dwc/pcie-designware.c | 16 +++++++++++++---
>  1 file changed, 13 insertions(+), 3 deletions(-)

Reviewed-by: Rob Herring <robh@kernel.org>