Re: [PATCH] arm64: dts: qcom: sa8775p: Add new memory map updates to SA8775P

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, 23 Jan 2024 at 18:02, Bjorn Andersson <quic_bjorande@xxxxxxxxxxx> wrote:
>
> On Tue, Jan 23, 2024 at 08:23:37AM +0200, Dmitry Baryshkov wrote:
> > On Tue, 23 Jan 2024 at 04:58, Trilok Soni <quic_tsoni@xxxxxxxxxxx> wrote:
> > > On 1/22/2024 12:02 PM, Bjorn Andersson wrote:
> [..]
> > > As Brian M mentioned earlier, we want soc vendors to submit the support
> > > for their SOCs and platforms on top it as early as possible and it means
> > > such memory map changes will continue. Even memory map changes
> > > continue even few months after the commercial s/w release in certain cases
> > > due to critical bugs were found in some usecases which warrants the changes.
> >
> > So, can one handle such changes? Are we going to publish a list of
> > kernels to be used with the corresponding firmware images? Then what
> > if the developer wants to update just the kernel? Just to get this or
> > that non-platform-related feature. Or vice versa, what if the user is
> > stuck with an older kernel because some driver gets broken in the main
> > branch (which unfortunately happens sometimes)  Or what if the memory
> > map patch gets backported via the AUTOSEL process?
> > Unlike the Qualcomm binary distributions, the firmware and the kernel
> > version are no longer connected.
> >
> > That's why I keep on saying that memory map is an ABI. If it gets
> > changed, it is a completely new, incompatible platform.
>
> This is only a problem because we think the DeviceTree is a part of the
> kernel. If we actually tied the DeviceTree to the firmware - as it was
> intended - different firmware versions could come with different memory
> map.

Yes, up to some point. Because then DT gets incorporated into U-Boot...

> The one exception would be any remoteproc/pil firmware that is not
> relocatable, as these are distributed together with the OS (in some
> form) and not the boot/security/etc firmware.

-- 
With best wishes
Dmitry




[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux