Re: [PATCH v5 3/5] powerpc/85xx: add sleep and deep sleep support

[Zhao Chenhui <chenhui.zhao@freescale.com>]

On Fri, Jun 01, 2012 at 04:54:35PM -0500, Scott Wood wrote:
> On 05/11/2012 06:53 AM, Zhao Chenhui wrote:
> > From: Li Yang <leoli@freescale.com>
> > 
> > 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.
> > 
> > Some Freescale chips like MPC8536 and P1022 has deep sleep PM mode
> > in addtion to the sleep PM mode.
> > 
> > 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 sleep mode is equal to the Standby state in Linux. The deep sleep
> > mode is equal to the Suspend-to-RAM state of Linux Power Management.
> > 
> > Command to enter sleep mode.
> >   echo standby > /sys/power/state
> > Command to enter deep sleep mode.
> >   echo mem > /sys/power/state
> > 
> > Signed-off-by: Dave Liu <daveliu@freescale.com>
> > Signed-off-by: Li Yang <leoli@freescale.com>
> > Signed-off-by: Jin Qing <b24347@freescale.com>
> > Signed-off-by: Jerry Huang <Chang-Ming.Huang@freescale.com>
> > Cc: Scott Wood <scottwood@freescale.com>
> > Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com>
> > ---
> > Changes for v5:
> >  * Rename flush_disable_L1 to __flush_disable_L1.
> > 
> >  arch/powerpc/Kconfig                  |    2 +-
> >  arch/powerpc/include/asm/cacheflush.h |    5 +
> >  arch/powerpc/kernel/Makefile          |    3 +
> >  arch/powerpc/kernel/l2cache_85xx.S    |   53 +++
> >  arch/powerpc/platforms/85xx/Makefile  |    3 +
> >  arch/powerpc/platforms/85xx/sleep.S   |  609 +++++++++++++++++++++++++++++++++
> >  arch/powerpc/sysdev/fsl_pmc.c         |   91 ++++-
> >  arch/powerpc/sysdev/fsl_soc.h         |    5 +
> >  8 files changed, 752 insertions(+), 19 deletions(-)
> >  create mode 100644 arch/powerpc/kernel/l2cache_85xx.S
> >  create mode 100644 arch/powerpc/platforms/85xx/sleep.S
> > 
> > diff --git a/arch/powerpc/include/asm/cacheflush.h b/arch/powerpc/include/asm/cacheflush.h
> > index 94ec20a..baa000c 100644
> > --- a/arch/powerpc/include/asm/cacheflush.h
> > +++ b/arch/powerpc/include/asm/cacheflush.h
> > @@ -33,6 +33,11 @@ extern void flush_dcache_page(struct page *page);
> >  #if defined(CONFIG_FSL_BOOKE) || defined(CONFIG_6xx)
> >  extern void __flush_disable_L1(void);
> >  #endif
> > +#if defined(CONFIG_FSL_BOOKE)
> > +extern void flush_dcache_L1(void);
> > +#else
> > +#define flush_dcache_L1()	do { } while (0)
> > +#endif
> 
> It doesn't seem right to no-op this on other platforms.

The pmc_suspend_enter() in fsl_pmc.c used by mpc85xx and mpc86xx,
but flush_dcache_L1() have no definition in mpc86xx platform.
I will write flush_dcache_L1() for mpc86xx platform.

> 
> >  extern void __flush_icache_range(unsigned long, unsigned long);
> >  static inline void flush_icache_range(unsigned long start, unsigned long stop)
> > diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
> > index f5808a3..cb70dba 100644
> > --- a/arch/powerpc/kernel/Makefile
> > +++ b/arch/powerpc/kernel/Makefile
> > @@ -64,6 +64,9 @@ obj-$(CONFIG_FA_DUMP)		+= fadump.o
> >  ifeq ($(CONFIG_PPC32),y)
> >  obj-$(CONFIG_E500)		+= idle_e500.o
> >  endif
> > +ifneq ($(CONFIG_PPC_E500MC),y)
> > +obj-$(CONFIG_PPC_85xx)		+= l2cache_85xx.o
> > +endif
> 
> Can we introduce a symbol that specifically means pre-e500mc e500,
> rather than using negative logic?
> 
> I think something like CONFIG_PPC_E500_V1_V2 has been proposed before.

Agree. But CONFIG_PPC_E500_V1_V2 haven't been merged.

> 
> > -static int pmc_probe(struct platform_device *ofdev)
> > +static int pmc_probe(struct platform_device *pdev)
> >  {
> > -	pmc_regs = of_iomap(ofdev->dev.of_node, 0);
> > +	struct device_node *np = pdev->dev.of_node;
> > +
> > +	pmc_regs = of_iomap(np, 0);
> >  	if (!pmc_regs)
> >  		return -ENOMEM;
> >  
> > -	pmc_dev = &ofdev->dev;
> > +	pmc_flag = PMC_SLEEP;
> > +	if (of_device_is_compatible(np, "fsl,mpc8536-pmc"))
> > +		pmc_flag |= PMC_DEEP_SLEEP;
> > +
> > +	if (of_device_is_compatible(np, "fsl,p1022-pmc"))
> > +		pmc_flag |= PMC_DEEP_SLEEP;
> > +
> >  	suspend_set_ops(&pmc_suspend_ops);
> > +
> > +	pr_info("Freescale PMC driver\n");
> 
> If you're going to be noisy on probe, at least provide some useful info
> like whether deep sleep or jog are supported.
> 
> >  	return 0;
> >  }
> >  
> > diff --git a/arch/powerpc/sysdev/fsl_soc.h b/arch/powerpc/sysdev/fsl_soc.h
> > index c6d0073..949377d 100644
> > --- a/arch/powerpc/sysdev/fsl_soc.h
> > +++ b/arch/powerpc/sysdev/fsl_soc.h
> > @@ -48,5 +48,10 @@ extern struct platform_diu_data_ops diu_ops;
> >  void fsl_hv_restart(char *cmd);
> >  void fsl_hv_halt(void);
> >  
> > +/*
> > + * Cast the ccsrbar to 64-bit parameter so that the assembly
> > + * code can be compatible with both 32-bit & 36-bit.
> > + */
> > +extern void mpc85xx_enter_deep_sleep(u64 ccsrbar, u32 powmgtreq);
> 
> s/Cast the ccsrbar to 64-bit parameter/ccsrbar is u64 rather than
> phys_addr_t/
> 
> -Scott

OK. Thanks.

-Chenhui