From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefano Babic Date: Wed, 08 Jan 2014 09:55:10 +0100 Subject: [U-Boot] [PATCH 1/2] configs: mx6_common: Restrict CONFIG_ARM_ERRATA_742230 for multi-core In-Reply-To: <1389014059-9894-1-git-send-email-fabio.estevam@freescale.com> References: <1389014059-9894-1-git-send-email-fabio.estevam@freescale.com> Message-ID: <52CD126E.4020608@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Fabio, On 06/01/2014 14:14, Fabio Estevam wrote: > According to e9fd66defd (ARM: mx6: define CONFIG_ARM_ERRATA_742230), the > CONFIG_ARM_ERRATA_742230 option should only be applied to multi-core > variants, so restrict its usage for quad and dual-lite only. > > Signed-off-by: Fabio Estevam > --- > include/configs/mx6_common.h | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/include/configs/mx6_common.h b/include/configs/mx6_common.h > index 514d634..0b8db85 100644 > --- a/include/configs/mx6_common.h > +++ b/include/configs/mx6_common.h > @@ -17,7 +17,9 @@ > #ifndef __MX6_COMMON_H > #define __MX6_COMMON_H > > +#if defined(CONFIG_MX6Q) || defined(CONFIG_MX6DL) > #define CONFIG_ARM_ERRATA_742230 > +#endif > #define CONFIG_ARM_ERRATA_743622 > #define CONFIG_ARM_ERRATA_751472 > #define CONFIG_BOARD_POSTCLK_INIT > In Kernel I cannot read that the errata is related to a multicore processor. Indeed, it is related to the Cortex-A9 version. "This option enables the workaround for the 742230 Cortex-A9 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction between two write operations may not ensure the correct visibility ordering of the two writes. This workaround sets a specific bit in the diagnostic register of the Cortex-A9 which causes the DMB instruction to behave as a DSB, ensuring the correct behaviour of the two writes. " The fix was merged in kernel since a lot of time, before having multicore processors for ARM. At least the commit message does not seem coherent with the explanations in kernel. Maybe has solo a upgraded core version as dual/quad ? Best regards, Stefano -- ===================================================================== DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: +49-8142-66989-53 Fax: +49-8142-66989-80 Email: sbabic at denx.de =====================================================================