From: Florian Fainelli <f.fainelli@gmail.com>
To: Russell King - ARM Linux <linux@armlinux.org.uk>,
Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org,
Rob Herring <robh+dt@kernel.org>,
Mark Rutland <mark.rutland@arm.com>, Ray Jui <rjui@broadcom.com>,
Scott Branden <sbranden@broadcom.com>,
Jon Mason <jonmason@broadcom.com>,
"maintainer:BROADCOM IPROC ARM ARCHITECTURE"
<bcm-kernel-feedback-list@broadcom.com>,
"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS"
<devicetree@vger.kernel.org>,
open list <linux-kernel@vger.kernel.org>,
andrew@lunn.ch
Subject: Re: [PATCH 1/3] ARM: dts: NSP: Enable SFP on bcm958625hr
Date: Mon, 27 Aug 2018 15:36:50 -0700 [thread overview]
Message-ID: <6d6e6c18-c713-7d7d-a332-da73cca84cbe@gmail.com> (raw)
In-Reply-To: <20180827222646.GF30658@n2100.armlinux.org.uk>
On 08/27/2018 03:26 PM, Russell King - ARM Linux wrote:
> On Mon, Aug 27, 2018 at 01:03:42PM -0700, Florian Fainelli wrote:
>> Enable the SFP connected to port 5 of the switch and wire up all GPIOs
>> to the SFP cage. Because of a hardware limitation of the i2c controller
>> on the iProc SoCs which prevents large i2c (> 256 bytes) transactions to
>> work, we use the i2c-gpio interface instead, which does not have that
>> limitation. This allows us to read the SFP module EEPROM, which would
>> not be possible otherwise since it exceeds that size during a single
>> read transfer.
>
> We shouldn't exceed 256 bytes, since 256 bytes is the "page" size
> of the EEPROM. The most that we read in one block is either
> ETH_MODULE_SFF_8079_LEN or (ETH_MODULE_SFF_8472_LEN -
> ETH_MODULE_SFF_8079_LEN), both of which result in no more than 256
> byte reads.
You are right, I got things mixed up here, the controller's limitation
is actually 63 bytes per transfer, I will be rewording the commit
message accordingly.
--
Florian
next prev parent reply other threads:[~2018-08-27 22:37 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-08-27 20:03 [PATCH 0/3] ARM: NSP updates to support switch interrupts/SFP Florian Fainelli
2018-08-27 20:03 ` [PATCH 1/3] ARM: dts: NSP: Enable SFP on bcm958625hr Florian Fainelli
2018-08-27 20:35 ` Andrew Lunn
2018-08-27 20:52 ` Florian Fainelli
2018-08-27 21:09 ` Andrew Lunn
2018-08-27 21:17 ` Florian Fainelli
2018-08-27 21:31 ` Andrew Lunn
2018-08-27 21:09 ` Florian Fainelli
2018-08-27 22:26 ` Russell King - ARM Linux
2018-08-27 22:36 ` Florian Fainelli [this message]
2018-08-27 20:03 ` [PATCH 2/3] dt-bindings: net: dsa: Document B53 SRAB interrupts and registers Florian Fainelli
2018-08-27 20:03 ` [PATCH 3/3] ARM: dts: NSP: Wire up switch interrupts Florian Fainelli
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=6d6e6c18-c713-7d7d-a332-da73cca84cbe@gmail.com \
--to=f.fainelli@gmail.com \
--cc=andrew@lunn.ch \
--cc=bcm-kernel-feedback-list@broadcom.com \
--cc=devicetree@vger.kernel.org \
--cc=jonmason@broadcom.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=mark.rutland@arm.com \
--cc=rjui@broadcom.com \
--cc=robh+dt@kernel.org \
--cc=sbranden@broadcom.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).