From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: MIME-Version: 1.0 In-Reply-To: <576017C7.50609@arm.com> References: <1465912965-35500-1-git-send-email-rob.rice@broadcom.com> <1465912965-35500-2-git-send-email-rob.rice@broadcom.com> <576017C7.50609@arm.com> Date: Thu, 16 Jun 2016 09:50:23 -0400 Message-ID: Subject: Re: [PATCH RESEND 1/3] dt-bindings: add bindings documentation for PDC driver. From: Rob Rice Content-Type: multipart/alternative; boundary=001a113f231c0716e80535658533 To: Sudeep Holla Cc: Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Jassi Brar , Rob Herring , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, BCM Kernel Feedback , linux-kernel@vger.kernel.org, Ray Jui , Scott Branden , Jon Mason , Florian Fainelli , Anup Patel , Catalin Marinas , Will Deacon , Rob Rice List-ID: --001a113f231c0716e80535658533 Content-Type: text/plain; charset=UTF-8 On Tue, Jun 14, 2016 at 10:42 AM, Sudeep Holla wrote: > > > On 14/06/16 15:02, Rob Rice wrote: > >> From: Rob Rice >> >> Add the device tree binding documentation for the PDC hardware >> in Broadcom iProc SoCs. >> >> Signed-off-by: Rob Rice >> Acked-by: Rob Herring >> Reviewed-by: Ray Jui >> Reviewed-by: Anup Patel >> Reviewed-by: Scott Branden >> --- >> .../bindings/mailbox/brcm,iproc-pdc-mbox.txt | 23 >> ++++++++++++++++++++++ >> 1 file changed, 23 insertions(+) >> create mode 100644 >> Documentation/devicetree/bindings/mailbox/brcm,iproc-pdc-mbox.txt >> >> diff --git >> a/Documentation/devicetree/bindings/mailbox/brcm,iproc-pdc-mbox.txt >> b/Documentation/devicetree/bindings/mailbox/brcm,iproc-pdc-mbox.txt >> new file mode 100644 >> index 0000000..411ccf4 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/mailbox/brcm,iproc-pdc-mbox.txt >> @@ -0,0 +1,23 @@ >> +The PDC driver manages data transfer to and from various offload engines >> +on some Broadcom SoCs. An SoC may have multiple PDC hardware blocks. >> There is >> +one device tree entry per block. >> + >> +Required properties: >> +- compatible : Should be "brcm,iproc-pdc-mbox". >> +- reg: Should contain PDC registers location and length. >> +- interrupts: Should contain the IRQ line for the PDC. >> +- #mbox-cells: 1 >> +- brcm,rx-status-len: Length of metadata preceding received frames, in >> bytes. >> + >> > > Ideally the metadata is more associated with the software protocol built > on top of the mailbox controller. > > Is this metadata added by the hardware ? > > Otherwise it's better to make it part of the protocol rather than the > associating with the controller. > Yes, in fact this metadata is added by the PDC hardware itself. So it seems correct for the DT property to be on the controller. (There can be other metadata associated with the specific protocol (e.g., crypto engine), but that is accounted for elsewhere.) > +Optional properties: >> +- brcm,use-bcm-hdr: present if a BCM header precedes each frame. >> + >> > > Same here. Same answer. > > > -- > Regards, > Sudeep > --001a113f231c0716e80535658533 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable


On Tue, Jun 14, 2016 at 10:42 AM, Sudeep Holla <sudeep.holla@arm.co= m> wrote:


On 14/06/16 15:02, Rob Rice wrote:
From: Rob Rice <= rrice@broadcom.com>

Add the device tree binding documentation for the PDC hardware
in Broadcom iProc SoCs.

Signed-off-by: Rob Rice <rob.rice@broadcom.com>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
---
=C2=A0 .../bindings/mailbox/brcm,iproc-pdc-mbox.txt=C2=A0 =C2=A0 =C2=A0 =C2= =A0| 23 ++++++++++++++++++++++
=C2=A0 1 file changed, 23 insertions(+)
=C2=A0 create mode 100644 Documentation/devicetree/bindings/mailbox/brcm,ip= roc-pdc-mbox.txt

diff --git a/Documentation/devicetree/bindings/mailbox/brcm,iproc-pdc-mbox.= txt b/Documentation/devicetree/bindings/mailbox/brcm,iproc-pdc-mbox.txt
new file mode 100644
index 0000000..411ccf4
--- /dev/null
+++ b/Documentation/devicetree/bindings/mailbox/brcm,iproc-pdc-mbox.txt
@@ -0,0 +1,23 @@
+The PDC driver manages data transfer to and from various offload engines +on some Broadcom SoCs. An SoC may have multiple PDC hardware blocks. There= is
+one device tree entry per block.
+
+Required properties:
+- compatible : Should be "brcm,iproc-pdc-mbox".
+- reg: Should contain PDC registers location and length.
+- interrupts: Should contain the IRQ line for the PDC.
+- #mbox-cells: 1
+- brcm,rx-status-len: Length of metadata preceding received frames, in byt= es.
+

Ideally the metadata is more associated with the software protocol built on top of the mailbox controller.

Is this metadata added by the hardware ?

Otherwise it's better to make it part of the protocol rather than the associating with the controller.

Yes, in fact this metadata is added by the PDC h= ardware itself. So it seems correct for the DT property to be on the contro= ller. (There can be other metadata associated with the specific protocol (e= .g., crypto engine), but that is accounted for elsewhere.)


+Optional properties:
+- brcm,use-bcm-hdr:=C2=A0 present if a BCM header precedes each frame.
+

Same here.

Same answer.=C2=A0


--
Regards,
Sudeep

--001a113f231c0716e80535658533--