From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Figa Subject: Re: [PATCH 04/27] ARM: EXYNOS: Support secondary CPU boot of Exynos4212 Date: Fri, 11 Apr 2014 09:14:53 +0200 Message-ID: <5347966D.7040300@samsung.com> References: <1397122658-16013-1-git-send-email-cw00.choi@samsung.com> <1397122658-16013-5-git-send-email-cw00.choi@samsung.com> <20140411014424.GA14934@quad.lixom.net> <53477A19.6070509@samsung.com> <006f01cf554b$dbc6a2d0$9353e870$@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mailout2.w1.samsung.com ([210.118.77.12]:29773 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752152AbaDKHPB (ORCPT ); Fri, 11 Apr 2014 03:15:01 -0400 In-reply-to: <006f01cf554b$dbc6a2d0$9353e870$@samsung.com> Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: Sangbeom Kim , 'Chanwoo Choi' , 'Olof Johansson' Cc: linux-samsung-soc@vger.kernel.org, hyunhee.kim@samsung.com, sw0312.kim@samsung.com, linux-kernel@vger.kernel.org, yj44.cho@samsung.com, inki.dae@samsung.com, kyungmin.park@samsung.com, kgene.kim@samsung.com, linux-arm-kernel@lists.infradead.org Hi Sangbeom, On 11.04.2014 08:04, Sangbeom Kim wrote: > Hi, > On 04/11/2014 2:14 PM, Chanwoo Choi wrote: > >>>> { >>>> - exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0); >>>> + if (soc_is_exynos4212()) >>>> + exynos_smc(SMC_CMD_CPU1BOOT, 0, 0, 0); >>>> + else >>>> + exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0); >>> >>> /* */ >> >> It's better to ask system lsi person. We don't know it well. >> I got the guide about secondary boot from system lsi. >> But, this patch was completely tested. > > exynos_smc(SMC_CMD_CPU1BOOT, ...) is cpu hotplug SMC interface. > Exynos4212 is dual core processor. > Exynos4212 only have to boot cpu1 on smp boot. > So, Second parameter of exynos_smc is fixed by 0 which means cpu1. > It don't need to boot another cpu (ex. cpu2, cpu3 for quad core processor). > But In case of quad core processor (ex. Exynos4412), > It need to boot another cpu and specify parameter of booting core. > As I know, Exynos3250 is dual core. > So It can be included 1st condition too. Is the smc API defined to ignore the first argument of SMC_CMD_CPU1BOOT command for dual core systems or it is defined as should be zero? Best regards, Tomasz From mboxrd@z Thu Jan 1 00:00:00 1970 From: t.figa@samsung.com (Tomasz Figa) Date: Fri, 11 Apr 2014 09:14:53 +0200 Subject: [PATCH 04/27] ARM: EXYNOS: Support secondary CPU boot of Exynos4212 In-Reply-To: <006f01cf554b$dbc6a2d0$9353e870$@samsung.com> References: <1397122658-16013-1-git-send-email-cw00.choi@samsung.com> <1397122658-16013-5-git-send-email-cw00.choi@samsung.com> <20140411014424.GA14934@quad.lixom.net> <53477A19.6070509@samsung.com> <006f01cf554b$dbc6a2d0$9353e870$@samsung.com> Message-ID: <5347966D.7040300@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Sangbeom, On 11.04.2014 08:04, Sangbeom Kim wrote: > Hi, > On 04/11/2014 2:14 PM, Chanwoo Choi wrote: > >>>> { >>>> - exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0); >>>> + if (soc_is_exynos4212()) >>>> + exynos_smc(SMC_CMD_CPU1BOOT, 0, 0, 0); >>>> + else >>>> + exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0); >>> >>> /* */ >> >> It's better to ask system lsi person. We don't know it well. >> I got the guide about secondary boot from system lsi. >> But, this patch was completely tested. > > exynos_smc(SMC_CMD_CPU1BOOT, ...) is cpu hotplug SMC interface. > Exynos4212 is dual core processor. > Exynos4212 only have to boot cpu1 on smp boot. > So, Second parameter of exynos_smc is fixed by 0 which means cpu1. > It don't need to boot another cpu (ex. cpu2, cpu3 for quad core processor). > But In case of quad core processor (ex. Exynos4412), > It need to boot another cpu and specify parameter of booting core. > As I know, Exynos3250 is dual core. > So It can be included 1st condition too. Is the smc API defined to ignore the first argument of SMC_CMD_CPU1BOOT command for dual core systems or it is defined as should be zero? Best regards, Tomasz