From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Guo Subject: Re: [PATCH 15/18] ARM: vf610: PM: initial suspend/resume support Date: Fri, 1 Apr 2016 10:25:07 +0800 Message-ID: <20160401022507.GF18833@tiger> References: <1457576219-7971-1-git-send-email-stefan@agner.ch> <1457576219-7971-16-git-send-email-stefan@agner.ch> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1457576219-7971-16-git-send-email-stefan@agner.ch> Sender: linux-clk-owner@vger.kernel.org To: Stefan Agner Cc: mturquette@baylibre.com, sboyd@codeaurora.org, kernel@pengutronix.de, sergeimir@emcraft.com, tglx@linutronix.de, jason@lakedaemon.net, marc.zyngier@arm.com, robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org List-Id: devicetree@vger.kernel.org On Wed, Mar 09, 2016 at 06:16:56PM -0800, Stefan Agner wrote: > Add system suspend and resume support for Vybrid SoC. The standby > sleep state puts the SoC in STOP mode. The SoC can be woken through > an interrupt from GPC (Global Power Controller). The GPC can use any > interrupt as wake-up source. To save power the main PLL1 is bypassed > and uses the 24MHz on-chip oscillator. However, memory clock need to > be at full speed, hence the PLL2 needs to be on to keep the memory > clocked. The mode is completely implemented in C since we can access > the full memory at all times. The mode provides most power saving > while being able to be woken by any IRQ as wake-up source. > > The mem sleep state (Suspend-to-RAM) uses Vybrid's LPSTOP2 mode. This > mode powergates most parts of the SoC expect some peripherials such as > Wake-Up controller (WKPU) or LP RTC. Parts of the internal SRAM is > retained too. The suspend code written in assembly runs from this SRAM. > The code puts the main memory (DDR3) into self-refresh mode and takes > it out of self-refresh mode on resume. Verified with Colibri VF50/VF61 > V1.2A. > > Signed-off-by: Stefan Agner > --- > arch/arm/mach-imx/Makefile | 3 + > arch/arm/mach-imx/common.h | 10 + > arch/arm/mach-imx/mach-vf610.c | 8 + > arch/arm/mach-imx/pm-vf610.c | 634 ++++++++++++++++++++++++++++++++++++++ > arch/arm/mach-imx/suspend-vf610.S | 437 ++++++++++++++++++++++++++ > drivers/clk/imx/clk-vf610.c | 17 + > 6 files changed, 1109 insertions(+) > create mode 100644 arch/arm/mach-imx/pm-vf610.c > create mode 100644 arch/arm/mach-imx/suspend-vf610.S I know this is how we implemented suspend for i.MX6. But this is not the direction moving forward. When people was pushing a pile of code adding suspend for i.MX7D, I refused to take it and asked them to push those hardware details into firmware and use PSCI to implement suspend. I would like to suggest the same for Vybrid. Shawn