Re: [PATCH] ARM: imx6ull: Make suspend/resume work like on 6ul

From: Shawn Guo
Date: Tue Jun 06 2017 - 23:21:55 EST


On Tue, Jun 06, 2017 at 01:51:53PM +0300, Leonard Crestez wrote:
> On Mon, 2017-06-05 at 13:37 +0800, Shawn Guo wrote:
> > On Tue, May 30, 2017 at 07:11:19PM +0300, Leonard Crestez wrote:
> > >
> > > Suspend and resume on imx6ull is currenty not working because of some
> > > missed checks where behavior should match imx6ul.
> > >
> > > Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx>
> > > ---
> > >  arch/arm/mach-imx/mxc.h     | 6 ++++++
> > >  arch/arm/mach-imx/pm-imx6.c | 6 ++++--
> > >  2 files changed, 10 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/arch/arm/mach-imx/mxc.h b/arch/arm/mach-imx/mxc.h
> > > index 34f2ff6..e00d626 100644
> > > --- a/arch/arm/mach-imx/mxc.h
> > > +++ b/arch/arm/mach-imx/mxc.h
> > > @@ -39,6 +39,7 @@
> > >  #define MXC_CPU_IMX6SX 0x62
> > >  #define MXC_CPU_IMX6Q 0x63
> > >  #define MXC_CPU_IMX6UL 0x64
> > > +#define MXC_CPU_IMX6ULL 0x65
> > Since you are adding a new CPU type, you should probably patch
> > imx_soc_device_init() for it as well.
>
> Ok, I will resend as a 2-patch series.
>
> BTW, it actually seems to me that setting BM_CLPCR_BYP_MMDC_CH0_LPM_HS
> on imx6sl/sx/ul/ull is not actually needed. That bit (19) is documented
> as "reserved" in the Reference Manual and likely ignored by hardware.
>
> As far as I understand the MMDC on imx6qdl has two channels and unless
> 2-channel mode is enabled (not currently supported) the handshake with
> CH1 needs to be disabled. Other reduced chips only have one MMDC
> channel and that is CH1 (CH0 was removed) and nothing needs to be done
> from them. The only important thing is to avoid setting
> BM_CLPCR_BYP_MMDC_CH1_LPM_HS.
>
> However perhaps what I am saying is wrong for some early chip versions?
> Because this behavior of setting BM_CLPCR_BYP_MMDC_CH0_LPM_HS has been
> in the kernel for a long time.

@Anson, you might be the right person to comment here?

Shawn