[PATCH v2 11/18] ARM: OMAP5: PM: Add L2 memory power down support

Kevin Hilman khilman at linaro.org
Wed Apr 3 16:58:36 EDT 2013


Santosh Shilimkar <santosh.shilimkar at ti.com> writes:

> When the entire MPUSS cluster is powered down in device off state, L2 cache
> memory looses it's content and hence while targetting such a state,
> l2 cache needs to be flushed to main memory.
>
> Add the necessary low power code support for the same.
>
> Acked-by: Nishanth Menon <nm at ti.com>
> Signed-off-by: Santosh Shilimkar <santosh.shilimkar at ti.com>
> ---
>  arch/arm/mach-omap2/omap-secure.h     |    1 +
>  arch/arm/mach-omap2/sleep_omap4plus.S |   21 +++++++++++++++++++++
>  2 files changed, 22 insertions(+)
>
> diff --git a/arch/arm/mach-omap2/omap-secure.h b/arch/arm/mach-omap2/omap-secure.h
> index 1739468..a171a5a 100644
> --- a/arch/arm/mach-omap2/omap-secure.h
> +++ b/arch/arm/mach-omap2/omap-secure.h
> @@ -47,6 +47,7 @@
>  #define OMAP4_MON_L2X0_PREFETCH_INDEX	0x113
>  #define OMAP5_MON_CACHES_CLEAN_INDEX	0x103
>  #define OMAP5_MON_AUX_CTRL_INDEX	0x107
> +#define OMAP5_MON_L2AUX_CTRL_INDEX	0x104

this #define is not used in this patch.

Kevin

>  #define OMAP5_MON_AMBA_IF_INDEX		0x108
>  
> diff --git a/arch/arm/mach-omap2/sleep_omap4plus.S b/arch/arm/mach-omap2/sleep_omap4plus.S
> index 4a5e2e4..288f62f 100644
> --- a/arch/arm/mach-omap2/sleep_omap4plus.S
> +++ b/arch/arm/mach-omap2/sleep_omap4plus.S
> @@ -337,6 +337,7 @@ ENDPROC(omap4_cpu_resume)
>   *	0 - Nothing lost and no need to save: MPUSS INA/CSWR
>   *	1 - CPUx L1 and logic lost: CPU OFF, MPUSS INA/CSWR
>   *	2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR
> + *	3 - CPUx L1 and logic lost + GIC,L2 lost: MPU OSWR & L2 lost(debug only)
>   */
>  ENTRY(omap5_finish_suspend)
>  	stmfd	sp!, {r4-r12, lr}
> @@ -391,6 +392,26 @@ skip_secure_l1_clean_op:
>  	isb
>  	dsb
>  
> +	bl	omap4_get_sar_ram_base
> +	mov	r8, r0
> +	mrc	p15, 0, r5, c0, c0, 5		@ Read MPIDR
> +	ands	r5, r5, #0x0f
> +	ldreq	r0, [r8, #L2X0_SAVE_OFFSET0]	@ Retrieve L2 state
> +	ldrne	r0, [r8, #L2X0_SAVE_OFFSET1]
> +	cmp	r0, #3
> +	bne	do_wfi
> +	bl	omap4_get_sar_ram_base
> +	ldr	r9, [r0, #OMAP_TYPE_OFFSET]
> +	cmp	r9, #0x1			@ Check for HS device
> +	bne	skip_secure_l2_clean_op
> +	mov	r0, #1				@ Clean secure L2
> +	stmfd   r13!, {r4-r12, r14}
> +	ldr	r12, =OMAP5_MON_CACHES_CLEAN_INDEX
> +	DO_SMC
> +	ldmfd   r13!, {r4-r12, r14}
> +skip_secure_l2_clean_op:
> +	bl	v7_flush_dcache_all
> +
>  do_wfi:
>  	bl	omap_do_wfi



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