[PATCH 2/3] ARM: imx: enable periphery well bias for suspend

[Shawn Guo]

Forgot mentioning in patch #1, for patches touching arch/arm/, it's
good enough to send them to linux-arm-kernel list.  Copying list
linux-kernel isn't so necessary.

On Wed, Mar 20, 2013 at 01:39:39PM -0400, Anson Huang wrote:
> enable periphery charge pump for well biasing
> at suspend to reduce periphery leakage.
> 
> Signed-off-by: Anson Huang <b20788 at freescale.com>
> ---
>  arch/arm/mach-imx/clk-imx6q.c |   22 +++++++++++++++++++++-
>  arch/arm/mach-imx/common.h    |    4 ++--
>  arch/arm/mach-imx/pm-imx6q.c  |    4 +++-
>  3 files changed, 26 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm/mach-imx/clk-imx6q.c b/arch/arm/mach-imx/clk-imx6q.c
> index 2f9ff93..b365efc 100644
> --- a/arch/arm/mach-imx/clk-imx6q.c
> +++ b/arch/arm/mach-imx/clk-imx6q.c
> @@ -1,5 +1,5 @@
>  /*
> - * Copyright 2011 Freescale Semiconductor, Inc.
> + * Copyright 2011-2013 Freescale Semiconductor, Inc.
>   * Copyright 2011 Linaro Ltd.
>   *
>   * The code contained herein is licensed under the GNU General Public
> @@ -23,6 +23,9 @@
>  #include "clk.h"
>  #include "common.h"
>  
> +#define CCR				0x0
> +#define BM_CCR_WB_COUNT			(0x7 << 16)
> +
>  #define CCGR0				0x68
>  #define CCGR1				0x6c
>  #define CCGR2				0x70
> @@ -67,6 +70,23 @@ void imx6q_set_chicken_bit(void)
>  	writel_relaxed(val, ccm_base + CGPR);
>  }
>  
> +void imx6q_set_wb(bool enable)
> +{
> +	u32 val;
> +
> +	/* configurate well bias enable bit */

s/configurate/configure

> +	val = readl_relaxed(ccm_base + CLPCR);
> +	val &= ~BM_CLPCR_WB_PER_AT_LPM;
> +	val |= enable ? BM_CLPCR_WB_PER_AT_LPM : 0;
> +	writel_relaxed(val, ccm_base + CLPCR);
> +
> +	/* configurate well bias count */

Ditto

> +	val = readl_relaxed(ccm_base + CCR);
> +	val &= ~BM_CCR_WB_COUNT;
> +	val |= enable ? BM_CCR_WB_COUNT : 0;
> +	writel_relaxed(val, ccm_base + CCR);
> +}
> +
>  int imx6q_set_lpm(enum mxc_cpu_pwr_mode mode)
>  {
>  	u32 val = readl_relaxed(ccm_base + CLPCR);
> diff --git a/arch/arm/mach-imx/common.h b/arch/arm/mach-imx/common.h
> index 004c2b3..b9125cf 100644
> --- a/arch/arm/mach-imx/common.h
> +++ b/arch/arm/mach-imx/common.h
> @@ -1,5 +1,5 @@
>  /*
> - * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
> + * Copyright 2004-2013 Freescale Semiconductor, Inc. All Rights Reserved.
>   */
>  
>  /*
> @@ -134,7 +134,7 @@ extern void imx_anatop_pre_suspend(void);
>  extern void imx_anatop_post_resume(void);
>  extern int imx6q_set_lpm(enum mxc_cpu_pwr_mode mode);
>  extern void imx6q_set_chicken_bit(void);
> -

Unnecessary new line.

> +extern void imx6q_set_wb(bool enable);
>  extern void imx_cpu_die(unsigned int cpu);
>  extern int imx_cpu_kill(unsigned int cpu);
>  
> diff --git a/arch/arm/mach-imx/pm-imx6q.c b/arch/arm/mach-imx/pm-imx6q.c
> index 05b26cd..57ca274 100644
> --- a/arch/arm/mach-imx/pm-imx6q.c
> +++ b/arch/arm/mach-imx/pm-imx6q.c
> @@ -1,5 +1,5 @@
>  /*
> - * Copyright 2011 Freescale Semiconductor, Inc.
> + * Copyright 2011-2013 Freescale Semiconductor, Inc.
>   * Copyright 2011 Linaro Ltd.
>   *
>   * The code contained herein is licensed under the GNU General Public
> @@ -36,8 +36,10 @@ static int imx6q_pm_enter(suspend_state_t state)
>  		imx_gpc_pre_suspend();
>  		imx_anatop_pre_suspend();
>  		imx_set_cpu_jump(0, v7_cpu_resume);
> +		imx6q_set_wb(true);

Is it possible to have it called inside imx6q_set_lpm()?  If so, we can

1) Have imx6q_set_wb() be a static function in clk-imx6q.c
2) Apply the function for both STOP and WAIT mode

Shawn

>  		/* Zzz ... */
>  		cpu_suspend(0, imx6q_suspend_finish);
> +		imx6q_set_wb(false);
>  		imx_smp_prepare();
>  		imx_anatop_post_resume();
>  		imx_gpc_post_resume();
> -- 
> 1.7.9.5
> 
>