Re: [RFC PATCH v2 2/3] PCI: hisi: Make the HiSilicon PCIe host controller ECAM compliant

[Arnd Bergmann]

On Monday 08 February 2016 12:41:03 Gabriele Paoloni wrote:
> From: gabriele paoloni <gabriele.paoloni@xxxxxxxxxx>
> 
> This patch modifies the current Hip05/Hip06 PCIe host controller
> driver to make it ECAM compliant. This is needed in preparation
> for the ACPI based driver to allow both DT and ACPI drivers to
> use the same BIOS (that configure the Designware iATUs).
> 
> Signed-off-by: Gabriele Paoloni <gabriele.paoloni@xxxxxxxxxx>
> Signed-off-by: Dongdong Liu <liudongdong3@xxxxxxxxxx>
> 

Doesn't this break backwards compatibility?

I think you need to use a new compatible string in the firmware
if you change the register layout, and then change the driver
to support both the old and the new layout.

	Arnd