From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Murphy Subject: Re: [PATCH 1/2] ARM: realview: Fix PBX-A9 cache description Date: Fri, 15 Jul 2016 18:45:32 +0100 Message-ID: <5789213C.4060306@arm.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linus.walleij-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org Cc: mark.rutland-5wv7dgnIgG8@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org On 15/07/16 13:19, Robin Murphy wrote: > Clearly QEMU is very permissive in how its PL310 model may be set up, > but the real hardware turns out to be far more particular about things > actually being correct. Fix up the DT description so that the real > thing actually boots: > > - The arm,data-latency and arm,tag-latency properties need 3 cells to > be valid, otherwise we end up retaining the default 8-cycle latencies > which leads pretty quickly to lockup. > - The arm,dirty-latency property is only relevant to L210/L220, so get > rid of it. > - The cache geometry override also leads to lockup and/or general > misbehaviour. Irritatingly, the manual doesn't state the actual PL310 > configuration, but based on the boardfile code and poking registers > from the Boot Monitor, it would seem to be 8 sets of 16KB ways. FWIW, after an afternoon of bothering people I've tracked down the original spec for the test chip, and can confirm that the configuration is indeed 8x16KB with parity disabled. Robin. > With that, we can successfully boot to enjoy the fun of mismatched FPUs... > > Signed-off-by: Robin Murphy > --- > arch/arm/boot/dts/arm-realview-pbx-a9.dts | 9 ++++----- > 1 file changed, 4 insertions(+), 5 deletions(-) > > diff --git a/arch/arm/boot/dts/arm-realview-pbx-a9.dts b/arch/arm/boot/dts/arm-realview-pbx-a9.dts > index db808f92dd79..90d00b407f85 100644 > --- a/arch/arm/boot/dts/arm-realview-pbx-a9.dts > +++ b/arch/arm/boot/dts/arm-realview-pbx-a9.dts > @@ -70,13 +70,12 @@ > * associativity as these may be erroneously set > * up by boot loader(s). > */ > - cache-size = <1048576>; // 1MB > - cache-sets = <4096>; > + cache-size = <131072>; // 128KB > + cache-sets = <512>; > cache-line-size = <32>; > arm,parity-disable; > - arm,tag-latency = <1>; > - arm,data-latency = <1 1>; > - arm,dirty-latency = <1>; > + arm,tag-latency = <1 1 1>; > + arm,data-latency = <1 1 1>; > }; > > scu: scu@1f000000 { > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html