On 29/03/17 14:00, Hanjun Guo wrote:

On 03/29/2017 08:38 PM, Lorenzo Pieralisi wrote:

quoted

On Wed, Mar 29, 2017 at 07:52:48PM +0800, Hanjun Guo wrote:

quoted

Hi Lorenzo,

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

quoted

Hi Hanjun, Marc,

On Tue, Mar 07, 2017 at 08:40:05PM +0800, Hanjun Guo wrote:

quoted

From: Hanjun Guo <redacted>

For devices connecting to ITS, the devices need to identify themself
through a dev id; this dev id is represented in the IORT table in named
component node [1] for platform devices, so this patch adds code that
scans the IORT table to retrieve the devices' dev id.

Leveraging the iort_node_map_platform_id() IORT API, add a new function
call, iort_pmsi_get_dev_id() and use it in its_pmsi_prepare() to allow
retrieving dev id in ACPI platforms.

[1]: https://static.docs.arm.com/den0049/b/DEN0049B_IO_Remapping_Table.pdf

Signed-off-by: Hanjun Guo <redacted>
[lorenzo.pieralisi at arm.com: rewrote commit log]
Signed-off-by: Lorenzo Pieralisi <redacted>
Tested-by: Ming Lei <redacted>
Tested-by: Wei Xu <xuwei5@hisilicon.com>
Tested-by: Sinan Kaya <redacted>
Cc: Marc Zyngier <redacted>
Cc: Lorenzo Pieralisi <redacted>
Cc: Tomasz Nowicki <redacted>
Cc: Thomas Gleixner <redacted>
---
  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.

quoted

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?

	M.
-- 
Jazz is not dead. It just smells funny...