From: "Michael S. Tsirkin" <mst@redhat.com>
To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jailhouse <jailhouse-dev@googlegroups.com>,
"liang yan" <lyan@suse.com>,
"Alex Bennée" <alex.bennee@linaro.org>,
qemu-devel <qemu-devel@nongnu.org>,
"virtio-comment@lists.oasis-open.org"
<virtio-comment@lists.oasis-open.org>
Subject: Re: [RFC] ivshmem v2: Shared memory device specification
Date: Mon, 27 Jul 2020 09:20:09 -0400 [thread overview]
Message-ID: <20200727091802-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <f109fe5a-92eb-e5a5-bb83-ada42b3a9b61@siemens.com>
On Mon, May 25, 2020 at 09:58:28AM +0200, Jan Kiszka wrote:
> #### Vendor Specific Capability (ID 09h)
>
> This capability must always be present.
>
> | Offset | Register | Content |
> |-------:|:--------------------|:-----------------------------------------------|
> | 00h | ID | 09h |
> | 01h | Next Capability | Pointer to next capability or 00h |
> | 02h | Length | 20h if Base Address is present, 18h otherwise |
> | 03h | Privileged Control | Bit 0 (read/write): one-shot interrupt mode |
> | | | Bits 1-7: Reserved (0 on read, writes ignored) |
> | 04h | State Table Size | 32-bit size of read-only State Table |
> | 08h | R/W Section Size | 64-bit size of common read/write section |
> | 10h | Output Section Size | 64-bit size of output sections |
> | 18h | Base Address | optional: 64-bit base address of shared memory |
>
> All registers are read-only. Writes are ignored, except to bit 0 of
> the Privileged Control register.
Is there value in making this follow the virtio vendor-specific
capability format? That will cost several extra bytes - do you envision
having many of these in the config space?
Also, do we want to define an extended capability format in case this
is a pci extended capability?
--
MST
next prev parent reply other threads:[~2020-07-27 13:21 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-25 7:58 [RFC] ivshmem v2: Shared memory device specification Jan Kiszka
2020-06-17 15:32 ` Alex Bennée
2020-06-17 16:10 ` Jan Kiszka
2020-07-15 13:27 ` [virtio-comment] " Stefan Hajnoczi
2020-07-17 16:15 ` Jan Kiszka
2020-07-23 6:54 ` Stefan Hajnoczi
2020-07-23 7:02 ` Jan Kiszka
2020-07-27 12:29 ` Stefan Hajnoczi
2020-07-27 13:20 ` Michael S. Tsirkin [this message]
2020-07-27 13:39 ` [virtio-comment] " Jan Kiszka
2020-07-27 13:56 ` Michael S. Tsirkin
2020-07-27 14:17 ` Jan Kiszka
2020-07-27 14:19 ` Michael S. Tsirkin
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=20200727091802-mutt-send-email-mst@kernel.org \
--to=mst@redhat.com \
--cc=alex.bennee@linaro.org \
--cc=jailhouse-dev@googlegroups.com \
--cc=jan.kiszka@siemens.com \
--cc=lyan@suse.com \
--cc=qemu-devel@nongnu.org \
--cc=virtio-comment@lists.oasis-open.org \
/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).