RE: [PATCH 3/3][v4] staging: fsl-mc: move bus driver out of staging
From: Laurentiu Tudor
Date: Mon May 22 2017 - 04:43:06 EST
> -----Original Message-----
> From: Marc Zyngier [mailto:marc.zyngier@xxxxxxx]
> Sent: Monday, May 22, 2017 10:41 AM
> On Mon, May 22 2017 at 7:12:39 am GMT, Laurentiu Tudor
> <laurentiu.tudor@xxxxxxx> wrote:
> Hi Laurentiu,
> > Hi Marc,
> >> -----Original Message-----
> >> From: Marc Zyngier [mailto:marc.zyngier@xxxxxxx]
> >> Sent: Saturday, May 20, 2017 9:43 AM
> >> To: Matthias Brugger <matthias.bgg@xxxxxxxxx>
> >> On Fri, May 19 2017 at 02:41:43 PM, Matthias Brugger
> >> <matthias.bgg@xxxxxxxxx> wrote:
> >> > On 19/05/17 15:13, laurentiu.tudor@xxxxxxx wrote:
> >> >> From: Stuart Yoder <stuart.yoder@xxxxxxx>
> >> >>
> >> >> Move the source files out of staging into their final locations:
> >> >> -include files in drivers/staging/fsl-mc/include go to include/linux/fsl
> >> >> -irq-gic-v3-its-fsl-mc-msi.c goes to drivers/irqchip
> >> >
> >> > This driver has as compatible "arm,gic-v3-its". I wonder if this is
> >> > correct and if it should be moved like this out of staging.
> >> This is no different from the way we handle *any* bus that uses the
> >> GICv3 ITS as an MSI controller. Each bus provides its glue code that
> >> latches onto the ITS node, and calls into the generic code.
> >> Now, when it comes to moving this out of staging, here is my concern:
> >> There is mention of a userspace tool (restool) used to control the
> >> HW. Where is this tool? Where is the user ABI documented?
> > The tool is published here:
> > https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgit
> > hub.com%2Fqoriq-open-
> > served=0
> > There are two ways of configuring the mc-bus:
> > - a static one, through a FDT based configuration file (we call it
> > DPL), documented in the refman linked below, chapter 22.
> > - a dynamic one, using this restool utility.
> > Please note the usage of restool is optional.
> Optional or not, it still is a userspace ABI, and while I can see restool issuing ioctl
> system calls to configure the HW, I cannot see the corresponding code in the
> kernel tree. So how does it work?
> If the syscall interface is not present in the mainline kernel, drop the reference
> to it in the documentation. If it is there (and I obviously missed it), document it,
> and get it reviewed.
Our original plan was to first get the bus out of staging and after that submit the restool support ASAP (patches are done - so I'm thinking at few days timeframe).
if this is not acceptable, I can drop the restool reference from the README and resubmit the patch series. We'll re-add the reference together with the restool support patches.
> If there are associated DT bindings to the kernel code, they
> must be documented (and reviewed) as part of the device-tree documentation,
> and not in some obscure, hard to access document.
There's only one binding involved and it's already accepted .
> > We're also working on publishing the docs on github so that they're
> > more accessible.
> That'd be great, because the way the registration process is presented, I'd have
> to agree to the Access Agreement *before* having a chance to read it. Not
> going to happen...
Sorry about that. Not much I can do. :-(
Best Regards, Laurentiu