Re: [PATCH V2 01/10] Documentation: dt-bindings: mailbox: tegra: Add binding for HSP mailbox

From: Joseph Lo
Date: Tue Jul 19 2016 - 03:09:20 EST

On 07/19/2016 07:13 AM, Stephen Warren wrote:
On 07/11/2016 10:08 AM, Stephen Warren wrote:
On 07/11/2016 08:14 AM, Rob Herring wrote:
On Thu, Jul 07, 2016 at 12:35:02PM -0600, Stephen Warren wrote:
On 07/07/2016 12:13 PM, Sivaram Nair wrote:
On Tue, Jul 05, 2016 at 05:04:22PM +0800, Joseph Lo wrote:
Add DT binding for the Hardware Synchronization Primitives (HSP). The
HSP is designed for the processors to share resources and communicate
together. It provides a set of hardware synchronization primitives
interprocessor communication. So the interprocessor communication
protocols can use hardware synchronization primitive, when operating
between two processors not in an SMP relationship.

diff --git a/include/dt-bindings/mailbox/tegra186-hsp.h

+#define HSP_MBOX_TYPE_DB 0x0
+#define HSP_MBOX_TYPE_SM 0x1
+#define HSP_MBOX_TYPE_SS 0x2
+#define HSP_MBOX_TYPE_AS 0x3
+#define HSP_DB_MASTER_BPMP 19
+#define HSP_MBOX_ID(type, ID) \
+ (HSP_MBOX_TYPE_##type << 16 | ID)

It will be nicer if you avoid the macro glue magic '##' for 'type'. I
would also suggest to use braces around 'type' and 'ID'.

This technique been used without issue in quite a few other places
issue, and has the benefit of simplifying the text wherever the
macro is
used. What issue do you foresee?

I'm not a fan of using the macros to begin with and less so anything
more complex than a single constant value. I'd rather see 2 cells here
with the first being the id and the 2nd being the type.

An issue with token pasting is grepping for DB, SM, etc. in kernel tree
is probably noisy. Not such a big deal here, but a major PIA when you
have more complex sets of includes.

Is that a NAK or simply a suggestion? Having a single cell makes DT
parsing a bit simpler, since pretty much every SW stack provides a
default "one-cell" of_xlate implementation, whereas >1 cell means custom
code for of_xlate.

I didn't see a response to this. Joseph, let's just use two cells
instead. I'm rather desperately waiting for this binding to be complete
so I can finalize the U-Boot code that uses it, and it sounds like
changing to two cells will get an ack faster. Can you post an updated
version of this series today/ASAP to get things moving? Thanks.

Okay, will use two cells instead.