All of lore.kernel.org
 help / color / mirror / Atom feed
From: Peter Maydell <peter.maydell@linaro.org>
To: QEMU Developers <qemu-devel@nongnu.org>
Cc: Hao Wu <wuhaotsh@google.com>, Bin Meng <bin.meng@windriver.com>,
	Alistair Francis <alistair.francis@wdc.com>,
	Markus Armbruster <armbru@redhat.com>,
	Qemu-block <qemu-block@nongnu.org>
Subject: does drive_get_next(IF_NONE) make sense?
Date: Tue, 2 Nov 2021 15:14:02 +0000	[thread overview]
Message-ID: <CAFEAcA9zmPds0+jHm8VY465XEhK6bbVPd+nDob1ruRPaHOua_Q@mail.gmail.com> (raw)

Does it make sense for a device/board to do drive_get_next(IF_NONE) ?

At the moment we have exactly one user of this, which is
hw/misc/sifive_u_otp.c. This is a model of a one-time-programmable
fuse, and the drive is providing the backing store for the fuse
contents. Borrowing an IF_NONE for this seems a bit odd, but
it's not clear any of the other IF_ types is better.

We also just (this release cycle) added models of the Xilinx
efuse OTP fuses. Those have been implemented to use IF_PFLASH.
(This is a somewhat unfortunate inconsistency I guess.)

We also have a patchseries currently in the code review stage
which uses IF_NONE:
https://patchew.org/QEMU/20211101232346.1070813-1-wuhaotsh@google.com/20211101232346.1070813-6-wuhaotsh@google.com/
Here we are trying to provide a drive as backing store for some
EEPROMs that hang off the i2c buses on some npcm7xx boards.

Are these uses of IF_NONE OK, or should we be doing something
else (using IF_PFLASH, defining a new IF_*, ???)

thanks
-- PMM


             reply	other threads:[~2021-11-02 15:18 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-02 15:14 Peter Maydell [this message]
2021-11-02 15:28 ` does drive_get_next(IF_NONE) make sense? Philippe Mathieu-Daudé
2021-11-03  8:41 ` Markus Armbruster
2021-11-03  9:19   ` Thomas Huth
2021-11-12 13:33     ` Markus Armbruster
2021-11-14 17:16       ` Peter Maydell
2021-11-15  5:31         ` Markus Armbruster
2021-11-15  7:12           ` Alistair Francis
2021-11-15 16:09             ` Thomas Huth
2021-11-18 13:03               ` Alistair Francis
2021-11-18 13:20                 ` Peter Maydell
2021-11-15 13:24           ` Kevin Wolf
2021-11-15 13:31             ` Peter Maydell
2021-11-15 15:13               ` Kevin Wolf
2021-11-15 15:28               ` Markus Armbruster

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=CAFEAcA9zmPds0+jHm8VY465XEhK6bbVPd+nDob1ruRPaHOua_Q@mail.gmail.com \
    --to=peter.maydell@linaro.org \
    --cc=alistair.francis@wdc.com \
    --cc=armbru@redhat.com \
    --cc=bin.meng@windriver.com \
    --cc=qemu-block@nongnu.org \
    --cc=qemu-devel@nongnu.org \
    --cc=wuhaotsh@google.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.