From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Osipenko Subject: Re: [PATCH] ARM: tegra20: Store CPU "resettable" status in IRAM Date: Mon, 19 Jan 2015 18:14:30 +0300 Message-ID: <54BD1F56.1010209@gmail.com> References: <1421319545-23920-1-git-send-email-digetx@gmail.com> <1421319545-23920-2-git-send-email-digetx@gmail.com> <20150119141224.GF23778@ulmo.nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20150119141224.GF23778-AwZRO8vwLAwmlAP/+Wk3EA@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Thierry Reding Cc: Stephen Warren , Alexandre Courbot , Peter De Schrijver , linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-tegra@vger.kernel.org 19.01.2015 17:12, Thierry Reding =D0=BF=D0=B8=D1=88=D0=B5=D1=82: > On Thu, Jan 15, 2015 at 01:58:57PM +0300, Dmitry Osipenko wrote: >> Commit 7232398abc6a ("ARM: tegra: Convert PMC to a driver") changed = tegra_resume() >> location storing from late to early and, as a result, broke suspend = on Tegra20. >> PMC scratch register 41 is used by tegra LP1 resume code for retriev= ing stored >> physical memory address of common resume function and in the same ti= me used by >> tegra20_cpu_shutdown() (shared by Tegra20 cpuidle driver and platfor= m SMP code), >> which is storing CPU1 "resettable" status. It implies strict order o= f scratch >> register usage, otherwise resume function address is lost on Tegra20= after >> disabling non-boot CPU's on suspend. Fix it by storing "resettable" = status in >> IRAM instead of PMC scratch register. >> >> Signed-off-by: Dmitry Osipenko >> Fixes: 7232398abc6a (ARM: tegra: Convert PMC to a driver) >> Cc: # v3.17+ >> --- >> arch/arm/mach-tegra/cpuidle-tegra20.c | 5 ++--- >> arch/arm/mach-tegra/reset-handler.S | 10 +++++++--- >> arch/arm/mach-tegra/reset.h | 4 ++++ >> arch/arm/mach-tegra/sleep-tegra20.S | 37 ++++++++++++++++++++---= ------------ >> arch/arm/mach-tegra/sleep.h | 4 ++++ >> 5 files changed, 38 insertions(+), 22 deletions(-) > > I'm leaning towards applying this. Stephen, Alex, Peter: any objectio= ns? > > Thierry > Btw, I'm preparing cleanup for cpuidle and hotplug code. So this asm "u= gliness"=20 should go away. --=20 Dmitry