[PATCH 08/12] pm: at91: rename file name: pm_slowclock.S -->pm_suspend.S

Sylvain Rochet sylvain.rochet at finsecur.com
Fri Jan 23 11:17:19 PST 2015


Hello Wenyou,

On Tue, Jan 20, 2015 at 04:17:01PM +0800, Wenyou Yang wrote:
> 
> diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S
> new file mode 100644
> index 0000000..420e730
> --- /dev/null


> +	/* Turn off the main oscillator */
> +	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
> +	bic	tmp1, tmp1, #AT91_PMC_MOSCEN

at91sam9x5 and probably others need a key here:
	orr     tmp1, tmp1, #AT91_PMC_KEY

> +	str	tmp1, [pmc, #AT91_CKGR_MOR]



> +	/* Wait for interrupt */
> +	mcr	p15, 0, tmp1, c7, c0, 4

The linux-3.10-at91 branch uses a different approach which seem 
necessary for newer board, you probably forget to merge the following:

/*
 * Put the processor to enter into Standby mode, wait for interrupt to wakeup
 */
	.macro _do_wfi

#if defined(CONFIG_CPU_V7)
	dsb

	/* Disable the processor clock */
	mov	tmp1, #AT91_PMC_PCK
	str	tmp1, [pmc, #AT91_PMC_SCDR]

	wfi		@ Wait For Interrupt
#else
	mcr	p15, 0, tmp1, c7, c0, 4
#endif

	.endm

	.text

ENTRY(at91_slow_clock)
(...)
	/* Wait for interrupt */
	_do_wfi
(...)




> +	/* Turn on the main oscillator */
> +	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
> +	orr	tmp1, tmp1, #AT91_PMC_MOSCEN

at91sam9x5 and probably others need a key here:
        orr     tmp1, tmp1, #AT91_PMC_KEY

> +	str	tmp1, [pmc, #AT91_CKGR_MOR]



What about the following parts which are also in linux-3.10-at91 branch 
but not in this rework, are they necessary ?

sdr_sr_done:
	/* Disable MPDDRC Clock*/
	cmp	ddrcid, #0
	beq	2f
	bic	tmp2, ddrcid, #0xe0 /* fetch lowest 5 bits */
	mov	tmp1, #0x01
	mov	tmp1, tmp1, lsl tmp2

	tst	ddrcid, #0x20	/* > 32 ? */
	beq	1f
	str	tmp1, [pmc, #AT91_PMC_PCDR1]
	b	2f
1:
	str	tmp1, [pmc, #AT91_PMC_PCDR]
2:

	/* Disable DDR Clock */
	mov 	tmp1, #AT91_PMC_SYS_DDR
	str	tmp1, [pmc, #AT91_PMC_SCDR]




	/* Enable MPDDRC Clock*/
	cmp	ddrcid, #0
	beq	4f
	bic	tmp2, ddrcid, #0xe0 /* fetch lowest 5 bits */
	mov	tmp1, #0x01
	mov	tmp1, tmp1, lsl tmp2

	tst	ddrcid, #0x20	/* > 32 ? */
	beq	3f
	str	tmp1, [pmc, #AT91_PMC_PCER1]
	b	4f
3:
	str	tmp1, [pmc, #AT91_PMC_PCER]
4:

	/* Enable DDR clock */
	mov 	tmp1, #AT91_PMC_SYS_DDR
	str	tmp1, [pmc, #AT91_PMC_SCER]



Sylvain



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