[U-Boot] [PATCH v5 19/26] arm:trats:pmic: Power consumption reduction state for Samsung's TRATS board

Minkyu Kang mk7.kang at samsung.com
Thu Nov 8 11:32:09 CET 2012


On 06/11/12 02:28, Lukasz Majewski wrote:
> When charging battery is necessary, the development board needs to
> be turned into low power mode for better efficiency.
> 
> Signed-off-by: Lukasz Majewski <l.majewski at samsung.com>
> Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
> Cc: Minkyu Kang <mk7.kang at samsung.com>
> ---
> Changes for v2:
> - None
> Changes for v3:
> - None
> Changes for v4:
> - None
> Changes for v5:
> - None
> ---
>  board/samsung/trats/trats.c |   41 +++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 41 insertions(+), 0 deletions(-)
> 
> diff --git a/board/samsung/trats/trats.c b/board/samsung/trats/trats.c
> index 5c23744..a8a97bf 100644
> --- a/board/samsung/trats/trats.c
> +++ b/board/samsung/trats/trats.c
> @@ -89,6 +89,47 @@ void i2c_init_board(void)
>  	s5p_gpio_direction_output(&gpio2->y4, 1, 1);
>  }
>  
> +static void trats_low_power_mode(void)
> +{
> +	struct exynos4_clock *clk =
> +	    (struct exynos4_clock *)samsung_get_base_clock();
> +	struct exynos4_power *pwr =
> +	    (struct exynos4_power *)samsung_get_base_power();
> +
> +	/* Power down CORE1 */
> +	writel(0x0, &pwr->arm_core1_configuration);
> +
> +	/* Change the APLL frequency */
> +	writel(0xa0c80604, &clk->apll_con0);

Magic code?
please define this codes or at least add some comments here.

> +	/* Change CPU0 clock divider */
> +	writel(0x00000100, &clk->div_cpu0);
> +	/* CLK_DIV_STAT_CPU0 - wait until clock gets stable */
> +	while (readl(&clk->div_stat_cpu0) & 0x1111111)
> +		;
> +
> +	/* Change clock divider ratio for DMC */
> +	writel(0x13113117, &clk->div_dmc0);

ditto.

> +	while (readl(&clk->div_stat_dmc0) & 0x11111111)
> +		;
> +
> +	/* Turn off unnecessary power domains */
> +	writel(0x0, &pwr->xxti_configuration);	/* XXTI */
> +	writel(0x0, &pwr->cam_configuration);	/* CAM */
> +	writel(0x0, &pwr->tv_configuration);    /* TV */
> +	writel(0x0, &pwr->mfc_configuration);   /* MFC */
> +	writel(0x0, &pwr->g3d_configuration);   /* G3D */
> +	writel(0x0, &pwr->gps_configuration);   /* GPS */
> +	writel(0x0, &pwr->gps_alive_configuration);	/* GPS_ALIVE */
> +
> +	/* Turn off unnecessary clocks */
> +	writel(0x0, &clk->gate_ip_cam);	/* CAM */
> +	writel(0x0, &clk->gate_ip_tv);          /* TV */
> +	writel(0x0, &clk->gate_ip_mfc);	/* MFC */
> +	writel(0x0, &clk->gate_ip_g3d);	/* G3D */
> +	writel(0x0, &clk->gate_ip_image);	/* IMAGE */
> +	writel(0x0, &clk->gate_ip_gps);	/* GPS */
> +}
> +
>  static int pmic_init_max8997(void)
>  {
>  	struct pmic *p = pmic_get("MAX8997_PMIC");
> 

Thanks.
Minkyu Kang.


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