From: Tobias Waldekranz <tobias@waldekranz•com>
To: Andrew Lunn <andrew@lunn•ch>
Cc: davem@davemloft•net, kuba@kernel•org, f.fainelli@gmail•com,
olteanv@gmail•com, netdev@vger•kernel.org, linux@armlinux•org.uk,
chris.packham@alliedtelesis•co.nz
Subject: Re: [PATCH net 2/4] net: dsa: mv88e6xxx: Give chips more time to activate their PPUs
Date: Fri, 06 Dec 2024 14:39:25 +0100 [thread overview]
Message-ID: <87ldwt7wxe.fsf@waldekranz.com> (raw)
In-Reply-To: <518b8e8c-aa84-4e8e-9780-a672915443e7@lunn.ch>
On fre, dec 06, 2024 at 14:18, Andrew Lunn <andrew@lunn•ch> wrote:
> On Fri, Dec 06, 2024 at 02:07:34PM +0100, Tobias Waldekranz wrote:
>> In a daisy-chain of three 6393X devices, delays of up to 750ms are
>> sometimes observed before completion of PPU initialization (Global 1,
>> register 0, bit 15) is signaled. Therefore, allow chips more time
>> before giving up.
>> static int mv88e6352_g1_wait_ppu_polling(struct mv88e6xxx_chip *chip)
>> {
>> int bit = __bf_shf(MV88E6352_G1_STS_PPU_STATE);
>> + int err, i;
>>
>> - return mv88e6xxx_g1_wait_bit(chip, MV88E6XXX_G1_STS, bit, 1);
>> + for (i = 0; i < 20; i++) {
>> + err = _mv88e6xxx_wait_bit(chip, chip->info->global1_addr,
>> + MV88E6XXX_G1_STS, bit, 1, NULL);
>> + if (err != -ETIMEDOUT)
>> + break;
>> + }
>
> The commit message does not indicate why it is necessary to swap to
> _mv88e6xxx_wait_bit().
It is not strictly necessary, I just wanted to avoid flooding the logs
with spurious timeout errors. Do you want me to update the message?
>> +
>> + if (err) {
>> + dev_err(chip->dev, "PPU did not come online: %d\n", err);
>> + return err;
>> + }
>> +
>> + if (i)
>> + dev_warn(chip->dev,
>> + "PPU was slow to come online, retried %d times\n", i);
>
> dev_dbg()? Does the user care if it took longer than one loop
> iteration?
My resoning was: While it does seem fine that the device takes this long
to initialize, if it turns out that this is an indication of some bigger
issue, it might be good to have it recorded in the log.
next prev parent reply other threads:[~2024-12-06 13:39 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-06 13:07 [PATCH net 0/4] net: dsa: mv88e6xxx: Amethyst (6393X) fixes Tobias Waldekranz
2024-12-06 13:07 ` [PATCH net 1/4] net: dsa: mv88e6xxx: Improve I/O related error logging Tobias Waldekranz
2024-12-06 13:07 ` [PATCH net 2/4] net: dsa: mv88e6xxx: Give chips more time to activate their PPUs Tobias Waldekranz
2024-12-06 13:18 ` Andrew Lunn
2024-12-06 13:39 ` Tobias Waldekranz [this message]
2024-12-07 15:38 ` Andrew Lunn
2024-12-08 21:23 ` Tobias Waldekranz
2024-12-15 23:12 ` Tobias Waldekranz
2024-12-16 9:22 ` Andrew Lunn
2024-12-10 12:10 ` Paolo Abeni
2024-12-10 14:07 ` Tobias Waldekranz
2024-12-06 13:07 ` [PATCH net 3/4] net: dsa: mv88e6xxx: Never force link on in-band managed MACs Tobias Waldekranz
2024-12-06 13:07 ` [PATCH net 4/4] net: dsa: mv88e6xxx: Limit rsvd2cpu policy to user ports on 6393X Tobias Waldekranz
2024-12-08 20:23 ` [PATCH net 0/4] net: dsa: mv88e6xxx: Amethyst (6393X) fixes Chris Packham
2024-12-08 21:32 ` Tobias Waldekranz
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=87ldwt7wxe.fsf@waldekranz.com \
--to=tobias@waldekranz$(echo .)com \
--cc=andrew@lunn$(echo .)ch \
--cc=chris.packham@alliedtelesis$(echo .)co.nz \
--cc=davem@davemloft$(echo .)net \
--cc=f.fainelli@gmail$(echo .)com \
--cc=kuba@kernel$(echo .)org \
--cc=linux@armlinux$(echo .)org.uk \
--cc=netdev@vger$(echo .)kernel.org \
--cc=olteanv@gmail$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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