From: Peter Maydell <peter.maydell@linaro.org>
To: Kevin Mambu <kevin.mambu@pm.me>
Cc: "qemu-discuss@nongnu.org" <qemu-discuss@nongnu.org>,
"Alex Bennée" <alex.bennee@linaro.org>,
"Philippe Mathieu-Daudé" <f4bug@amsat.org>,
qemu-devel <qemu-devel@nongnu.org>
Subject: Re: Difficulties to access guest memory in TCG plugins
Date: Fri, 25 Jun 2021 10:27:27 +0100 [thread overview]
Message-ID: <CAFEAcA-tS51CCvEB4eG7vkB+edTrZyxNV29YV++XF5SNw_4D+w@mail.gmail.com> (raw)
In-Reply-To: <ue5FWr9Im37PzO94ccnHkiZJawfs6i4R8DdYdA5aVq_8BJHXDFLa4ojQpN1CIh5trBH4wiAZNTPzy1V98TQFX4FPh_Z7jngXuYNTaR_hSS4=@pm.me>
On Fri, 25 Jun 2021 at 10:25, Kevin Mambu <kevin.mambu@pm.me> wrote:
> In the scope of my Ph. D subject, I want to model a DMA-like mechanism for quick prototyping and evaluation, the plugin emulates an MMIO with Control/Status Registers. I am actually able to pass parameters to the Control/Status Registers through store instruction without any issue. Only the data transfer between two guest memory regions fails at times.
This really isn't what the plugin API is intended for -- it's meant
for tracing and similar sorts of "track what the guest is doing" activities.
If you want to model an MMIO device, you're better off just writing a device
model like any of the others in QEMU, I think: the APIs for doing that
are much more well-proven and there's plenty of examples in the tree
of DMA and other devices.
-- PMM
next prev parent reply other threads:[~2021-06-25 9:58 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <o1Yk83q9b8fPEPYKowd-FS7TM3GAByNtQScLqBwokjniIxwBv-rLo3gQU5MAjLDZGJn9hOGiPudeSXvp3TS-QxouCtlVqHbsnGqXf8dKs_k=@protonmail.com>
2021-06-24 8:14 ` Difficulties to access guest memory in TCG plugins Philippe Mathieu-Daudé
2021-06-24 19:41 ` Alex Bennée
2021-06-25 9:18 ` Kevin Mambu
2021-06-25 9:27 ` Peter Maydell [this message]
2021-06-25 11:41 ` Kevin Mambu
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