From mboxrd@z Thu Jan 1 00:00:00 1970 From: shiraz.linux.kernel@gmail.com (shiraz hashim) Date: Sun, 18 Apr 2010 20:05:09 +0530 Subject: Query: ARM Cortex A9: Is invalidating L1 data cache mandatory before usage In-Reply-To: <20100417181457.GA24299@n2100.arm.linux.org.uk> References: <4BC985BD.8040704@st.com> <20100417181457.GA24299@n2100.arm.linux.org.uk> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hello Russell, On Sat, Apr 17, 2010 at 11:44 PM, Russell King - ARM Linux wrote: > On Sat, Apr 17, 2010 at 03:26:13PM +0530, Shiraz HASHIM wrote: >> Hello, >> >> I am trying to port Linux on ARM Cortex A9 based platform and what >> I see is that if I don't invalidate the data cache before enabling >> and using it (in arch/arm/boot/compressed/head.S) the system crashes. >> >> I need to do the same for second core before calling secondary_startup. >> >> Is it normal? Why then other platforms (cortex A9 based) are not doing >> this. What am I missing? > > Yes, it's required. ?See: > > http://www.arm.linux.org.uk/developer/booting.php OK. So it means that the bootloader is expected to do this invalidation or cleanup, and for secondary cpus we can do it before calling secondary_startup. Am I right ? regards Shiraz