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

Tom Rini
2013-03-15T15:05:24Z

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@ti.com>
> Signed-off-by: Satyanarayana, Sandhya <sandhya.satyanarayana@ti.com>
> Cc: Tom Rini <trini@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@ti.com>

Lars, I suspect pcm051 also could use a change like this.

--
Tom
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