Re: [PATCH v9 10/15] ACPI: platform-msi: retrieve dev id from IORT

From: Hanjun Guo
Date: Wed Mar 29 2017 - 23:07:49 EST


On 03/30/2017 01:32 AM, Lorenzo Pieralisi wrote:
On Wed, Mar 29, 2017 at 05:13:54PM +0100, Lorenzo Pieralisi wrote:
On Wed, Mar 29, 2017 at 03:52:47PM +0100, Marc Zyngier wrote:
On 29/03/17 14:00, Hanjun Guo wrote:
On 03/29/2017 08:38 PM, Lorenzo Pieralisi wrote:
On Wed, Mar 29, 2017 at 07:52:48PM +0800, Hanjun Guo wrote:
Hi Lorenzo,

On 03/29/2017 06:14 PM, Lorenzo Pieralisi wrote:
Hi Hanjun, Marc,

On Tue, Mar 07, 2017 at 08:40:05PM +0800, Hanjun Guo wrote:
[...]
drivers/acpi/arm64/iort.c | 24 ++++++++++++++++++++++++
drivers/irqchip/irq-gic-v3-its-platform-msi.c | 3 ++-
include/linux/acpi_iort.h | 5 +++++
3 files changed, 31 insertions(+), 1 deletion(-)

To simplify merging ACPI/IRQCHIP changes via different trees it
would be good to split this patch; I am not sure what's the best
way of handling it though given that we would end up in a merge
ordering dependency anyway (ie we can create an empty stub
for iort_pmsi_get_dev_id() but that would create a dependency
between ARM64 and irqchip trees anyway).

The first 12 patches for ACPI platform MSI and later 3 patches
for mbigen have no "physical" dependency, which means they can
be merged and compiled independently, they only have functional
dependency only.

We already had SAS, XGE, USB and even UART drivers depend on
the mbigen ACPI support, so I don't think the dependency of ACPI
platform MSI and mbigen patches cares much if those two parts are
merged in one merge window, even they are merged independently via
different tree.


Please let me know what's your preferred way of handling this.

So in my opinion, they can be merged independently via ARM64 and
irqchip tree with no ordering dependency, is it OK?

I am speaking about merging MBIgen AND ITS patches via IRQCHIP and
ACPI/IORT for ARM64, that's why I replied to this patch. I do not
think that's feasible to split patches in two separate branches
without having a dependency between them.

Sure, the last three patches can go via IRQCHIP but that was not
my question :)

Sorry, I misunderstood that :(

Since it's not feasible to split patches, the best way I got is that
we get Marc's ack then merge it.

I believe there is a way to make this work without too much hassle. I
suggest we drop the ITS change from this patch entirely, and I instead
queue this patch:

https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/commit/?h=irq/irqchip-4.12&id=e6db07d0f3b6da1f8cfd485776bfefa4fcdbfc45

That way, no dependency between the two trees. Lorenzo takes all the
patches flagged "ACPI", I take all those flagged "irqchip" or "msi", and
everything should be perfectly standalone.

Thoughts?

Perfect for me. Hanjun, I can cherry pick Marc's patch above, rework
this patch and post the resulting branch for everyone to have a final
test.

git://git.kernel.org/pub/scm/linux/kernel/git/lpieralisi/linux.git acpi/arm64-acpi-4.12

Please have a look and let me know if that's ok, I planned to send
a PR to Catalin by the end of the week (first 7 patches up to
7fc3061df075 ("ACPI: platform: setup MSI domain for ACPI based platform
device")).

Perfect for me too, Lorenzo, Marc, Thank you very much.

I'm currently in paternity leave and can't reach the machine,
I had a detail review with the patches, they looks good to me,
Ma Jun and Wei Xu will test on Hisilicon machines and give the
feedback.

Thanks
Hanjun