Subject: [PATCH][V2] ux500 : decouple/recouple gic from the PRCMU

From: [email-masked] (Rickard Andersson)
Date: Thu, 9 Feb 2012 11:52:05 +0100

Hi Daniel!

Please see my embedded comments.

Also should we not keep the functions in pm.c file? I think Linus W 
advised us not to move stuff around at this stage.

BR
Rickard
> This patch allows to decouple and recouple the gic from the PRCMU.
> This is needed to put the A9 core in retention mode with the cpuidle
> driver.
>
> Signed-off-by: Daniel Lezcano<[email-masked]>
> ---
>   drivers/mfd/db8500-prcmu.c       |   29 +++++++++++++++++++++++++++++
>   include/linux/mfd/db8500-prcmu.h |    2 ++
>   include/linux/mfd/dbx500-prcmu.h |   16 ++++++++++++++++
>   3 files changed, 47 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/mfd/db8500-prcmu.c b/drivers/mfd/db8500-prcmu.c
> index af8e0ef..70f39a1 100644
> --- a/drivers/mfd/db8500-prcmu.c
> +++ b/drivers/mfd/db8500-prcmu.c
> @@ -787,6 +787,35 @@ int db8500_prcmu_set_power_state(u8 state, bool keep_ulp_clk, bool keep_ap_pll)
>   	return 0;
>   }
>
> +#define PRCMU_A9_MASK_REQ               0x00000328
> +#define PRCMU_A9_MASK_REQ_MASK          0x00000001
> +#define PRCMU_GIC_DELAY                 1
> +
> +/* This function decouple the gic from the prcmu */
> +void db8500_prcmu_gic_decouple(void)
> +{
> +	u32 val = readl(_PRCMU_BASE + PRCMU_A9_MASK_REQ);
> +
> +	/* Set bit 0 register value to 1 */
> +	writel((val&  ~PRCMU_A9_MASK_REQ_MASK) | PRCMU_A9_MASK_REQ_MASK,
> +	       _PRCMU_BASE + PRCMU_A9_MASK_REQ);
No need to AND with ~PRCMU_A9_MASK_REQ_MASK. This is enough:

writel((val | PRCMU_A9_MASK_REQ_MASK,
	_PRCMU_BASE + PRCMU_A9_MASK_REQ);

> +
> +	/* Make sure the register is updated */
> +	readl(_PRCMU_BASE + PRCMU_A9_MASK_REQ);
> +
> +	/* Wait a few cycles for the gic mask completion */
> +	udelay(PRCMU_GIC_DELAY);
> +}
> +
> +/* This function recouple the gic with the prcmu */
> +void db8500_prcmu_gic_recouple(void)
> +{
> +	u32 val = readl(_PRCMU_BASE + PRCMU_A9_MASK_REQ);
> +
> +	/* Set bit 0 register value to 0 */
> +	writel((val&  ~PRCMU_A9_MASK_REQ_MASK), _PRCMU_BASE + PRCMU_A9_MASK_REQ);
> +}
> +
>   /* This function should only be called while mb0_transfer.lock is held. */
>   static void config_wakeups(void)
>   {
> diff --git a/include/linux/mfd/db8500-prcmu.h b/include/linux/mfd/db8500-prcmu.h
> index 60d27f7..4a1032c 100644
> --- a/include/linux/mfd/db8500-prcmu.h
> +++ b/include/linux/mfd/db8500-prcmu.h
> @@ -536,6 +536,8 @@ int prcmu_load_a9wdog(u8 id, u32 val);
>
>   void db8500_prcmu_system_reset(u16 reset_code);
>   int db8500_prcmu_set_power_state(u8 state, bool keep_ulp_clk, bool keep_ap_pll);
> +void db8500_prcmu_gic_disable(void);
> +void db8500_prcmu_gic_enable(void);
>   void db8500_prcmu_enable_wakeups(u32 wakeups);
>   int db8500_prcmu_set_epod(u16 epod_id, u8 epod_state);
>   int db8500_prcmu_request_clock(u8 clock, bool enable);
> diff --git a/include/linux/mfd/dbx500-prcmu.h b/include/linux/mfd/dbx500-prcmu.h
> index bac942f..a5fee69 100644
> --- a/include/linux/mfd/dbx500-prcmu.h
> +++ b/include/linux/mfd/dbx500-prcmu.h
> @@ -237,6 +237,22 @@ static inline int prcmu_set_power_state(u8 state, bool keep_ulp_clk,
>   			keep_ap_pll);
>   }
>
> +static inline void prcmu_gic_disable(void)
> +{
> +	if (machine_is_u5500())
> +		return;
> +	else
> +		return db8500_prcmu_gic_disable();
> +}
We have change name of this function in the .c file
> +
> +static inline void prcmu_gic_enable(void)
> +{
> +	if (machine_is_u5500())
> +		return;
> +	else
> +		return db8500_prcmu_gic_enable();
> +}
We have change name of this function in the .c file
> +
>   static inline int prcmu_set_epod(u16 epod_id, u8 epod_state)
>   {
>   	if (machine_is_u5500())