>To: Zhao Chenhui-B35336; linuxppc-dev@lists.ozlabs.org >Subject: Re: [PATCH 3/7] powerpc/85xx: add sleep and deep sleep support > >Hi Zhao, > >From: Li Yang <leoli at freescale.com> > >Some Freescale chips like MPC8536 and P1022 has deep sleep PM mode in >addtion to the sleep PM mode. > >In sleep PM mode, the clocks of e500 core and unused IP blocks is turned >off. IP blocks which are allowed to wake up the processor are still >running > >While in deep sleep PM mode, additionally, the power supply is removed >from e500 core and most IP blocks. Only the blocks needed to wake up the >chip out of deep sleep are ON. > >This patch supports 32-bit and 36-bit address space. > >The deep sleep mode is equal to the Suspend-to-RAM state of Linux Power >Management. > >Command to enter deep sleep mode. > echo mem > /sys/power/state > > >Thanks a lot for bringing this code to mainline. I was recently involved >in enabling deep sleep on a custom P1022 board, and would like to make >some remarks based on this experience. > >1. I think 85xx deep sleep code would be more complete if you also port >FSL > BSP code that saves eLBC configuration before entering deep sleep and > restores it afterwards. Otherwise all eLBC customization done by u- >boot is lost.
Thanks for the comment. That work is also being considered for upstream, but not in this series. > >2. You should implement fsl_deep_sleep() routine for 85xx. The default >implementation > in include/linux/fsl_devices.h always returns 0. The routine is used >by FSL USB host > driver, drivers/usb/host/ehci-fsl.c to restore USB hardware state >after deep sleep. > With default implementation USB is dead on 85xx after deep sleep if >USB PHY is > powered down completely. Added to the to-do list. Thanks. - Leo _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev