From: Andrew Lunn <andrew@lunn.ch>
To: Jijie Shao <shaojijie@huawei.com>
Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
pabeni@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org,
shenjian15@huawei.com, liuyonglong@huawei.com,
chenhao418@huawei.com, lantao5@huawei.com,
huangdonghua3@h-partners.com, yangshuaisong@h-partners.com,
huangdengdui@h-partners.com, jonathan.cameron@huawei.com,
salil.mehta@huawei.com, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH net 1/3] net: hns3: fix loopback test of serdes and phy is failed if duplex is half
Date: Wed, 17 Sep 2025 18:58:55 +0200 [thread overview]
Message-ID: <a060e5cf-c1cf-4dfa-b534-ddb72e8652f8@lunn.ch> (raw)
In-Reply-To: <20250917122954.1265844-2-shaojijie@huawei.com>
On Wed, Sep 17, 2025 at 08:29:52PM +0800, Jijie Shao wrote:
> If duplex setting is half, mac and phy can not transmit and receive data
> at the same time.
Lets think about the fundamentals of Ethernet, MII and half duplex.
Is this specific to your MAC/PHY combination, or just generally true?
Should this is solved in phylib, because it is true for every MAC/PHY
combination? phylib returning -EINAL to phy_loopback() would seem like
the correct thing to do.
Is it specific to your PHY, but independent of the MAC? Then the PHY
should return -EINVAL in its set_loopback() method.
> + hdev->hw.mac.duplex_last = phydev->duplex;
> +
> + ret = phy_set_bits(phydev, MII_BMCR, BMCR_FULLDPLX);
A MAC driver should not be doing this. What if the PHY is C45 only?
And Marvell PHYs need a soft reset before such an operation take
effect.
Andrew
---
pw-bot: cr
next prev parent reply other threads:[~2025-09-17 16:59 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-17 12:29 [PATCH net 0/3] There are some bugfix for the HNS3 ethernet driver Jijie Shao
2025-09-17 12:29 ` [PATCH net 1/3] net: hns3: fix loopback test of serdes and phy is failed if duplex is half Jijie Shao
2025-09-17 16:58 ` Andrew Lunn [this message]
2025-09-19 6:36 ` Jijie Shao
2025-09-17 12:29 ` [PATCH net 2/3] net: hns3: return error code when function fails Jijie Shao
2025-09-17 12:29 ` [PATCH net 3/3] net: hns3: use user configure after hardware reset when using kernel PHY Jijie Shao
2025-09-17 17:11 ` Andrew Lunn
2025-09-19 6:07 ` Jijie Shao
2025-09-19 12:20 ` Andrew Lunn
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=a060e5cf-c1cf-4dfa-b534-ddb72e8652f8@lunn.ch \
--to=andrew@lunn.ch \
--cc=andrew+netdev@lunn.ch \
--cc=chenhao418@huawei.com \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=horms@kernel.org \
--cc=huangdengdui@h-partners.com \
--cc=huangdonghua3@h-partners.com \
--cc=jonathan.cameron@huawei.com \
--cc=kuba@kernel.org \
--cc=lantao5@huawei.com \
--cc=linux-kernel@vger.kernel.org \
--cc=liuyonglong@huawei.com \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=salil.mehta@huawei.com \
--cc=shaojijie@huawei.com \
--cc=shenjian15@huawei.com \
--cc=yangshuaisong@h-partners.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
all inboxes | Powered by JetHome®