[PATCH 2/6] ARM: OMAP4 PM: Add IO Daisychain support

[Rajendra Nayak]

Djamil,

On Thursday 23 February 2012 09:28 PM, Elaidi, Djamil wrote:
> Hi Kristo,
>
> I think you must also add a omap_test_timeout() check after the Trigger WUCLKIN disable, to verify WUCLK_STATUS has come back to 0.
> This is needed because the IO daisy chain will not be ready until the WUCLKIN falling edge has propagated.

You are right, this was missed and needs to be added.
Thanks for the review.

regards,
Rajendra

>
> +	/* Trigger WUCLKIN disable */
> +	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK, 0x0,
> +			OMAP4430_PRM_DEVICE_INST, OMAP4_PRM_IO_PMCTRL_OFFSET);
> +	return;
> +	omap_test_timeout(
> +		(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
> +			OMAP4_PRM_IO_PMCTRL_OFFSET)&
> +			OMAP4430_WUCLK_STATUS_MASK)>>
> +			OMAP4430_WUCLK_STATUS_SHIFT) == 0),
> +		MAX_IOPAD_LATCH_TIME, i);
>
>
> Best regards
> Djamil ELAÏDI
> +33 4 97 27 50 97
> Software Systems Engineer
> OMAP Platform Business Unit - PSI Modem Integration
> Texas Instruments
>
> -----Original Message-----
> From: linux-omap-owner at vger.kernel.org [mailto:linux-omap-owner at vger.kernel.org] On Behalf Of Kristo, Tero
> Sent: jeudi 23 février 2012 14:22
> To: linux-omap at vger.kernel.org; Hilman, Kevin
> Cc: linux-arm-kernel at lists.infradead.org; Nayak, Rajendra; Sripathy, Vishwanath
> Subject: [PATCH 2/6] ARM: OMAP4 PM: Add IO Daisychain support
>
> From: Rajendra Nayak<rnayak at ti.com>
>
> patch adds IO Daisychain support for OMAP4 as per section 3.9.4 in OMAP4430
> Public TRM.
>
> Signed-off-by: Rajendra Nayak<rnayak at ti.com>
> Signed-off-by: Vishwanath BS<vishwanath.bs at ti.com>
> Signed-off-by: Tero Kristo<t-kristo at ti.com>
> ---
>   arch/arm/mach-omap2/prm44xx.c |   32 ++++++++++++++++++++++++++++++++
>   arch/arm/mach-omap2/prm44xx.h |    1 +
>   2 files changed, 33 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/prm44xx.c b/arch/arm/mach-omap2/prm44xx.c
> index 33dd655..1557647 100644
> --- a/arch/arm/mach-omap2/prm44xx.c
> +++ b/arch/arm/mach-omap2/prm44xx.c
> @@ -230,6 +230,41 @@ void omap44xx_prm_restore_irqen(u32 *saved_mask)
>   				 OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);
>   }
>
> +/**
> + * Maximum time(us) it takes to output the signal WUCLKOUT of the last pad of
> + * the I/O ring after asserting WUCLKIN high
> + */
> +#define MAX_IOPAD_LATCH_TIME 1000
> +
> +/* OMAP4 IO Daisychain trigger sequence */
> +void omap4_trigger_wuclk_ctrl(void)
> +{
> +	int i = 0;
> +
> +	/* Enable GLOBAL_WUEN */
> +	if (!(omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
> +		OMAP4_PRM_IO_PMCTRL_OFFSET)&  OMAP4430_GLOBAL_WUEN_MASK))
> +		omap4_prm_rmw_inst_reg_bits(OMAP4430_GLOBAL_WUEN_MASK,
> +			OMAP4430_GLOBAL_WUEN_MASK, OMAP4430_PRM_DEVICE_INST,
> +			OMAP4_PRM_IO_PMCTRL_OFFSET);
> +
> +	/* Trigger WUCLKIN enable */
> +	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK,
> +			OMAP4430_WUCLK_CTRL_MASK, OMAP4430_PRM_DEVICE_INST,
> +			OMAP4_PRM_IO_PMCTRL_OFFSET);
> +	omap_test_timeout(
> +		(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
> +			OMAP4_PRM_IO_PMCTRL_OFFSET)&
> +			OMAP4430_WUCLK_STATUS_MASK)>>
> +			OMAP4430_WUCLK_STATUS_SHIFT) == 1),
> +		MAX_IOPAD_LATCH_TIME, i);
> +
> +	/* Trigger WUCLKIN disable */
> +	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK, 0x0,
> +			OMAP4430_PRM_DEVICE_INST, OMAP4_PRM_IO_PMCTRL_OFFSET);
> +	return;
> +}
> +
>   static int __init omap4xxx_prcm_init(void)
>   {
>   	if (cpu_is_omap44xx())
> diff --git a/arch/arm/mach-omap2/prm44xx.h b/arch/arm/mach-omap2/prm44xx.h
> index 7978092..a840f0f 100644
> --- a/arch/arm/mach-omap2/prm44xx.h
> +++ b/arch/arm/mach-omap2/prm44xx.h
> @@ -762,6 +762,7 @@ void omap4_prm_vp_clear_txdone(u8 vp_id);
>   extern u32 omap4_prm_vcvp_read(u8 offset);
>   extern void omap4_prm_vcvp_write(u32 val, u8 offset);
>   extern u32 omap4_prm_vcvp_rmw(u32 mask, u32 bits, u8 offset);
> +extern void omap4_trigger_wuclk_ctrl(void);
>
>   /* PRM interrupt-related functions */
>   extern void omap44xx_prm_read_pending_irqs(unsigned long *events);