On 2016-03-31 19:25, Shawn Guo wrote: > 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 <stefan@xxxxxxxx> >> --- >> 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. Yeah I saw your comment on the i.MX7D patchset, and kind of hoped it does not apply for Vybrid :-) I see, need to look into PSCI closer, and see how much work it would be to set that up and transfer the code into it... -- Stefan -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
