From: Ard Biesheuvel <ardb@kernel.org>
To: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-efi <linux-efi@vger.kernel.org>,
Linux ARM <linux-arm-kernel@lists.infradead.org>,
Russell King <linux@armlinux.org.uk>,
Marc Zyngier <maz@kernel.org>, Nicolas Pitre <nico@fluxnic.net>,
Catalin Marinas <catalin.marinas@arm.com>,
Tony Lindgren <tony@atomide.com>
Subject: Re: [PATCH v3 0/5] ARM: decompressor: use by-VA cache maintenance for v7 cores
Date: Tue, 25 Feb 2020 18:30:44 +0100 [thread overview]
Message-ID: <CAKv+Gu9chiLCJ=HKLq4sXAP2ooqkRB-mfKVyEJ3tqxuxQTQgrg@mail.gmail.com> (raw)
In-Reply-To: <CAKv+Gu8MOZHFLw-Of5yK15Q1z9gpOmdQNmYF405XRAkeiCoXDw@mail.gmail.com>
On Tue, 25 Feb 2020 at 18:18, Ard Biesheuvel <ardb@kernel.org> wrote:
>
> On Tue, 25 Feb 2020 at 16:48, Linus Walleij <linus.walleij@linaro.org> wrote:
> >
> > On Mon, Feb 24, 2020 at 1:17 PM Ard Biesheuvel <ardb@kernel.org> wrote:
> >
> > > While making changes to the EFI stub startup code, I noticed that we are
> > > still doing set/way maintenance on the caches when booting on v7 cores.
> > > This works today on VMs by virtue of the fact that KVM traps set/way ops
> > > and cleans the whole address space by VA on behalf of the guest, and on
> > > most v7 hardware, the set/way ops are in fact sufficient when only one
> > > core is running, as there usually is no system cache. But on systems
> > > like SynQuacer, for which 32-bit firmware is available, the current cache
> > > maintenance only pushes the data out to the L3 system cache, where it
> > > is not visible to the CPU once it turns the MMU and caches off.
> > >
> > > So instead, switch to the by-VA cache maintenance that the architecture
> > > requires for v7 and later (and ARM1176, as a side effect).
> >
> > I took this v3 patch set for a ride on some ARMv7 and ARMv6
> > (hardware) boards using zImage:s so the compressed path
> > should be exercised:
> >
> > - Ux500 (ARMv7 Cortex A9 x 2) works like a charm
> > - RealView PB11MPCore (ARM1176 x 4 MPCore) works like a charm
> >
> > Tested-by: Linus Walleij <linus.walleij@linaro.org>
> >
> > I can do more thorough tests with more boards if needed.
> >
>
> Thanks Linus. Do you happen to have any boards that boot with appended DTB?
Actually, I can easily test that myself as well in QEMU.
next prev parent reply other threads:[~2020-02-25 17:30 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-24 12:17 [PATCH v3 0/5] ARM: decompressor: use by-VA cache maintenance for v7 cores Ard Biesheuvel
2020-02-24 12:17 ` [PATCH v3 1/5] efi/arm: Work around missing cache maintenance in decompressor handover Ard Biesheuvel
2020-02-24 12:17 ` [PATCH v3 2/5] efi/arm: Pass start and end addresses to cache_clean_flush() Ard Biesheuvel
2020-02-24 12:17 ` [PATCH v3 3/5] ARM: decompressor: factor out routine to obtain the inflated image size Ard Biesheuvel
2020-02-24 12:17 ` [PATCH v3 4/5] ARM: decompressor: prepare cache_clean_flush for doing by-VA maintenance Ard Biesheuvel
2020-02-24 12:17 ` [PATCH v3 5/5] ARM: decompressor: switch to by-VA cache maintenance for v7 cores Ard Biesheuvel
2020-02-25 15:48 ` [PATCH v3 0/5] ARM: decompressor: use " Linus Walleij
2020-02-25 17:18 ` Ard Biesheuvel
2020-02-25 17:30 ` Ard Biesheuvel [this message]
2020-02-25 21:25 ` Linus Walleij
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='CAKv+Gu9chiLCJ=HKLq4sXAP2ooqkRB-mfKVyEJ3tqxuxQTQgrg@mail.gmail.com' \
--to=ardb@kernel.org \
--cc=catalin.marinas@arm.com \
--cc=linus.walleij@linaro.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-efi@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=maz@kernel.org \
--cc=nico@fluxnic.net \
--cc=tony@atomide.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;
as well as URLs for NNTP newsgroup(s).