[U-Boot] [PATCH] am335x: Enable DDR PHY dynamic power down bit for DDR3 boards

[Lars Poeschel]

On Friday 15 March 2013 at 16:05:24, Tom Rini wrote:
> On Fri, Mar 15, 2013 at 12:41:16PM +0530, Vaibhav Hiremath wrote:
> > Enable DDR PHY dynamic power down bit, which enables
> > powering down the IO receiver when not performing read.
> > 
> > This also helps in reducing overall power consumption in
> > low power states (suspend/standby).
> > 
> > Signed-off-by: Vaibhav Hiremath <hvaibhav at ti.com>
> > Signed-off-by: Satyanarayana, Sandhya <sandhya.satyanarayana at ti.com>
> > Cc: Tom Rini <trini at ti.com>
> > ---
> > 
> >  arch/arm/include/asm/arch-am33xx/ddr_defs.h |    1 +
> >  board/ti/am335x/board.c                     |    6 ++++--
> >  2 files changed, 5 insertions(+), 2 deletions(-)
> > 
> > diff --git a/arch/arm/include/asm/arch-am33xx/ddr_defs.h
> > b/arch/arm/include/asm/arch-am33xx/ddr_defs.h index ae43ef8..7ab3baf
> > 100644
> > --- a/arch/arm/include/asm/arch-am33xx/ddr_defs.h
> > +++ b/arch/arm/include/asm/arch-am33xx/ddr_defs.h
> > @@ -28,6 +28,7 @@
> > 
> >  #define VTP_CTRL_START_EN	(0x1)
> >  #define PHY_DLL_LOCK_DIFF	0x0
> >  #define DDR_CKE_CTRL_NORMAL	0x1
> > 
> > +#define PHY_EN_DYN_PWRDN	(0x1 << 20)
> > 
> >  /* Micron MT47H128M16RT-25E */
> >  #define MT47H128M16RT25E_EMIF_READ_LATENCY	0x100005
> > 
> > diff --git a/board/ti/am335x/board.c b/board/ti/am335x/board.c
> > index 48e6896..22d7b25 100644
> > --- a/board/ti/am335x/board.c
> > +++ b/board/ti/am335x/board.c
> > @@ -251,7 +251,8 @@ static struct emif_regs ddr3_emif_reg_data = {
> > 
> >  	.sdram_tim2 = MT41J128MJT125_EMIF_TIM2,
> >  	.sdram_tim3 = MT41J128MJT125_EMIF_TIM3,
> >  	.zq_config = MT41J128MJT125_ZQ_CFG,
> > 
> > -	.emif_ddr_phy_ctlr_1 = MT41J128MJT125_EMIF_READ_LATENCY,
> > +	.emif_ddr_phy_ctlr_1 = MT41J128MJT125_EMIF_READ_LATENCY |
> > +				PHY_EN_DYN_PWRDN,
> > 
> >  };
> >  
> >  static struct emif_regs ddr3_evm_emif_reg_data = {
> > 
> > @@ -261,7 +262,8 @@ static struct emif_regs ddr3_evm_emif_reg_data = {
> > 
> >  	.sdram_tim2 = MT41J512M8RH125_EMIF_TIM2,
> >  	.sdram_tim3 = MT41J512M8RH125_EMIF_TIM3,
> >  	.zq_config = MT41J512M8RH125_ZQ_CFG,
> > 
> > -	.emif_ddr_phy_ctlr_1 = MT41J512M8RH125_EMIF_READ_LATENCY,
> > +	.emif_ddr_phy_ctlr_1 = MT41J512M8RH125_EMIF_READ_LATENCY |
> > +				PHY_EN_DYN_PWRDN,
> > 
> >  };
> >  #endif
> 
> Reviewed-by: Tom Rini <trini at ti.com>
> 
> Lars, I suspect pcm051 also could use a change like this.

Many thanks for the hint! Yes, I think this could also be of use for pcm051. 
I can care about it and make a patch for pcm051 after my two weeks holiday :)

Lars