Re: [RFC PATCH v1 1/4] arm/pci: PCI setup and PCI host bridge discovery within XEN on ARM.

[Julien Grall <julien@xxxxxxx>]

Hi Rahul,

On 23/07/2020 16:40, Rahul Singh wrote:
> XEN during boot will read the PCI device tree node “reg” property
> and will map the PCI config space to the XEN memory.
>
> XEN will read the “linux, pci-domain” property from the device tree
> node and configure the host bridge segment number accordingly.
>
> As of now "pci-host-ecam-generic" compatible board is supported.
>
> Change-Id: If32f7748b7dc89dd37114dc502943222a2a36c49
> Signed-off-by: Rahul Singh <rahul.singh@xxxxxxx>
> ---
>   xen/arch/arm/Kconfig                |   7 +
>   xen/arch/arm/Makefile               |   1 +
>   xen/arch/arm/pci/Makefile           |   4 +
>   xen/arch/arm/pci/pci-access.c       | 101 ++++++++++++++
>   xen/arch/arm/pci/pci-host-common.c  | 198 ++++++++++++++++++++++++++++
>   xen/arch/arm/pci/pci-host-generic.c | 131 ++++++++++++++++++
>   xen/arch/arm/pci/pci.c              | 112 ++++++++++++++++
>   xen/arch/arm/setup.c                |   2 +
>   xen/include/asm-arm/device.h        |   7 +-
>   xen/include/asm-arm/pci.h           |  97 +++++++++++++-
>   10 files changed, 654 insertions(+), 6 deletions(-)
As a general comment, I would suggest to split the patch in smaller 
chunk. This would help the review and also allow to provide more 
explanation on what is done.
For instance, I think it is possible to a split looking like:
    - Add framework to access an hostbridge
    - Add support for ECAM
    - Add code to initialize the PCI subsystem

There is also some small fixes in this code that probably can move in 
there own patches.
Cheers,

--
Julien Grall