[PATCH] mx5: modify pm and idle

[s.hauer@pengutronix.de (Sascha Hauer)]

On Fri, Sep 30, 2011 at 02:37:22PM +0800, Hui Wang wrote:
> Two problems exist in the current i.MX5 pm suspend/resume and idle
> functions. The first is the current i.MX5 suspend routine will call
> tzic_enable_wake(1) to set wake source, this will set all enabled
> irq as wake source rather than those wake capable. The second
> is i.MX5 idle will call mx5_cpu_lp_set() to prepare enter low power
> mode, but it forgets to call wfi instruction to enter this mode.
> 
> To fix these two problems, using generic irq chip pm interface and
> adding a new function mx5_arch_idle().
> 
> Signed-off-by: Hui Wang <jason77.wang@gmail.com>

As shawn already pointed out this conflicts with the imx-cleanup
branch. Can you rework this onto it? Shawn has reworked the SoC
specific idle stuff, so this is different now.

Also, please find a better subject for this patch. 'modify pm and idle'
is not enough.

Sascha

> ---
> 
> This patch is basing on the latest imx-features branch.
> 
> This patch is validated on the i.MX51 PDK board (CPU revision 2.0).
> 
> Since both pm suspend/resume and idle has close relation with
> mx5_cpu_lp_set() and tzic_enable_wake(), i choose to use one patch
> instead of independent two to address existing problems.
> 
>  arch/arm/mach-mx5/system.c              |   24 +++++++++++++++--
>  arch/arm/plat-mxc/include/mach/mxc.h    |    2 +-
>  arch/arm/plat-mxc/include/mach/system.h |    3 +-
>  arch/arm/plat-mxc/tzic.c                |   42 ++++++++++++++++++++++---------
>  4 files changed, 54 insertions(+), 17 deletions(-)
> 
> diff --git a/arch/arm/mach-mx5/system.c b/arch/arm/mach-mx5/system.c
> index 76ae8dc..92bf341 100644
> --- a/arch/arm/mach-mx5/system.c
> +++ b/arch/arm/mach-mx5/system.c
> @@ -10,11 +10,17 @@
>   * http://www.opensource.org/licenses/gpl-license.html
>   * http://www.gnu.org/copyleft/gpl.html
>   */
> +#include <linux/suspend.h>
> +#include <linux/clk.h>
>  #include <linux/platform_device.h>
>  #include <linux/io.h>
>  #include <mach/hardware.h>
> +#include <mach/common.h>
> +
>  #include "crm_regs.h"
>  
> +static struct clk *gpc_dvfs_clk;
> +
>  /* set cpu low power mode before WFI instruction. This function is called
>    * mx5 because it can be used for mx50, mx51, and mx53.*/
>  void mx5_cpu_lp_set(enum mxc_cpu_pwr_mode mode)
> @@ -54,9 +60,6 @@ void mx5_cpu_lp_set(enum mxc_cpu_pwr_mode mode)
>  			stop_mode = 1;
>  		}
>  		arm_srpgcr |= MXC_SRPGCR_PCR;
> -
> -		if (tzic_enable_wake(1) != 0)
> -			return;
>  		break;
>  	case STOP_POWER_ON:
>  		ccm_clpcr |= 0x2 << MXC_CCM_CLPCR_LPM_OFFSET;
> @@ -82,3 +85,18 @@ void mx5_cpu_lp_set(enum mxc_cpu_pwr_mode mode)
>  		__raw_writel(empgc1, MXC_SRPG_EMPGC1_SRPGCR);
>  	}
>  }
> +
> +void mx5_arch_idle(void)
> +{
> +		if (gpc_dvfs_clk == NULL)
> +			gpc_dvfs_clk = clk_get(NULL, "gpc_dvfs");
> +
> +		/* gpc clock is needed for SRPG */
> +		clk_enable(gpc_dvfs_clk);
> +		mx5_cpu_lp_set(WAIT_UNCLOCKED_POWER_OFF);
> +		if (tzic_enable_wake() != 0)
> +			goto exit;
> +		cpu_do_idle();
> +exit:
> +		clk_disable(gpc_dvfs_clk);
> +}
> diff --git a/arch/arm/plat-mxc/include/mach/mxc.h b/arch/arm/plat-mxc/include/mach/mxc.h
> index 0987923..c4d324a 100644
> --- a/arch/arm/plat-mxc/include/mach/mxc.h
> +++ b/arch/arm/plat-mxc/include/mach/mxc.h
> @@ -182,7 +182,7 @@ struct cpu_op {
>  	u32 cpu_rate;
>  };
>  
> -int tzic_enable_wake(int is_idle);
> +int tzic_enable_wake(void);
>  enum mxc_cpu_pwr_mode {
>  	WAIT_CLOCKED,		/* wfi only */
>  	WAIT_UNCLOCKED,		/* WAIT */
> diff --git a/arch/arm/plat-mxc/include/mach/system.h b/arch/arm/plat-mxc/include/mach/system.h
> index 51f02a9..5b6f991 100644
> --- a/arch/arm/plat-mxc/include/mach/system.h
> +++ b/arch/arm/plat-mxc/include/mach/system.h
> @@ -21,6 +21,7 @@
>  #include <mach/common.h>
>  
>  extern void mx5_cpu_lp_set(enum mxc_cpu_pwr_mode mode);
> +extern void mx5_arch_idle(void);
>  
>  static inline void arch_idle(void)
>  {
> @@ -51,7 +52,7 @@ static inline void arch_idle(void)
>  			"mcr p15, 0, %0, c1, c0, 0\n"
>  			: "=r" (reg));
>  	} else if (cpu_is_mx51())
> -		mx5_cpu_lp_set(WAIT_UNCLOCKED_POWER_OFF);
> +		mx5_arch_idle();
>  	else
>  		cpu_do_idle();
>  }
> diff --git a/arch/arm/plat-mxc/tzic.c b/arch/arm/plat-mxc/tzic.c
> index e993a18..bd73910 100644
> --- a/arch/arm/plat-mxc/tzic.c
> +++ b/arch/arm/plat-mxc/tzic.c
> @@ -72,14 +72,35 @@ static int tzic_set_irq_fiq(unsigned int irq, unsigned int type)
>  #define tzic_set_irq_fiq NULL
>  #endif
>  
> -static unsigned int *wakeup_intr[4];
> -
>  static struct mxc_extra_irq tzic_extra_irq = {
>  #ifdef CONFIG_FIQ
>  	.set_irq_fiq = tzic_set_irq_fiq,
>  #endif
>  };
>  
> +#ifdef CONFIG_PM
> +static void tzic_irq_suspend(struct irq_data *d)
> +{
> +	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
> +	int idx = gc->irq_base >> 5;
> +
> +	__raw_writel(gc->wake_active, tzic_base + TZIC_WAKEUP0(idx));
> +}
> +
> +static void tzic_irq_resume(struct irq_data *d)
> +{
> +	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
> +	int idx = gc->irq_base >> 5;
> +
> +	__raw_writel(__raw_readl(tzic_base + TZIC_ENSET0(idx)),
> +		     tzic_base + TZIC_WAKEUP0(idx));
> +}
> +
> +#else
> +#define tzic_irq_suspend NULL
> +#define tzic_irq_resume NULL
> +#endif
> +
>  static __init void tzic_init_gc(unsigned int irq_start)
>  {
>  	struct irq_chip_generic *gc;
> @@ -90,12 +111,13 @@ static __init void tzic_init_gc(unsigned int irq_start)
>  				    handle_level_irq);
>  	gc->private = &tzic_extra_irq;
>  	gc->wake_enabled = IRQ_MSK(32);
> -	wakeup_intr[idx] = &gc->wake_active;
>  
>  	ct = gc->chip_types;
>  	ct->chip.irq_mask = irq_gc_mask_disable_reg;
>  	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
>  	ct->chip.irq_set_wake = irq_gc_set_wake;
> +	ct->chip.irq_suspend = tzic_irq_suspend;
> +	ct->chip.irq_resume = tzic_irq_resume;
>  	ct->regs.disable = TZIC_ENCLEAR0(idx);
>  	ct->regs.enable = TZIC_ENSET0(idx);
>  
> @@ -166,23 +188,19 @@ void __init tzic_init_irq(void __iomem *irqbase)
>  /**
>   * tzic_enable_wake() - enable wakeup interrupt
>   *
> - * @param is_idle		1 if called in idle loop (ENSET0 register);
> - *				0 to be used when called from low power entry
>   * @return			0 if successful; non-zero otherwise
>   */
> -int tzic_enable_wake(int is_idle)
> +int tzic_enable_wake(void)
>  {
> -	unsigned int i, v;
> +	unsigned int i;
>  
>  	__raw_writel(1, tzic_base + TZIC_DSMINT);
>  	if (unlikely(__raw_readl(tzic_base + TZIC_DSMINT) == 0))
>  		return -EAGAIN;
>  
> -	for (i = 0; i < 4; i++) {
> -		v = is_idle ? __raw_readl(tzic_base + TZIC_ENSET0(i)) :
> -			*wakeup_intr[i];
> -		__raw_writel(v, tzic_base + TZIC_WAKEUP0(i));
> -	}
> +	for (i = 0; i < 4; i++)
> +		__raw_writel(__raw_readl(tzic_base + TZIC_ENSET0(i)),
> +			     tzic_base + TZIC_WAKEUP0(i));
>  
>  	return 0;
>  }
> -- 
> 1.7.6
> 
> 

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