diff mbox

[11/15] ARM: OMAP5: PM: Add L2 memory power down support

Message ID 1362139864-9233-12-git-send-email-santosh.shilimkar@ti.com (mailing list archive)
State New, archived
Headers show

Commit Message

Santosh Shilimkar March 1, 2013, 12:11 p.m. UTC
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.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
---
 arch/arm/mach-omap2/omap-secure.h     |    1 +
 arch/arm/mach-omap2/sleep_omap4plus.S |   30 ++++++++++++++++++++++++++++++
 2 files changed, 31 insertions(+)

Comments

Nishanth Menon March 1, 2013, 11:43 p.m. UTC | #1
On 17:41-20130301, Santosh Shilimkar wrote:
> 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.
> 
> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
> ---
>  arch/arm/mach-omap2/omap-secure.h     |    1 +
>  arch/arm/mach-omap2/sleep_omap4plus.S |   30 ++++++++++++++++++++++++++++++
>  2 files changed, 31 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
>  
>  #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 f4874e5..ea318be 100644
> --- a/arch/arm/mach-omap2/sleep_omap4plus.S
> +++ b/arch/arm/mach-omap2/sleep_omap4plus.S
> @@ -386,6 +386,27 @@ 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
umm, we store l2x0_pwrst_prepare(cpu, save_state);
which in turn stores into L2X0_SAVE_OFFSET - I am with you so far
save_state in omap4_enter_lowpower is:
PWRDM_POWER_INACTIVE: 0
PWRDM_POWER_OFF: 1
or 2 in the case of OSWR
what is 3? ref:
https://github.com/SantoshShilimkar/linux/blob/testing/3.10/omap5-int-rebuild/arch/arm/mach-omap2/omap-mpuss-lowpower.c#L298
> +	bne	do_wfi
> +	bl	omap4_get_sar_ram_base
> +	ldr	r9, [r0, #OMAP_TYPE_OFFSET]
> +	cmp	r9, #0x1			@ Check for HS device
my 2c:
off topic: somewhere down the line, I think we need to clear up these
into macros so that as in this case, omap4_mpuss_init populated value
should be the same as here with usage of same macro without reviewer
needing to track down where it was set with what.

> +	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:
> +	mov	r0, #2				@ Flush L2
v7_flush_dcache_all does not take parameters, right?
> +	bl	v7_flush_dcache_all
> +
>  do_wfi:
>  	bl	omap_do_wfi
>  
> @@ -427,6 +448,15 @@ ENTRY(omap5_cpu_resume)
>  	dsb
>  1:
>  #endif
> +	mrc	p15, 1, r0, c15, c0, 0		@ Read L2 ACTLR
> +	cmp	r0, #0x118			@ Check if it is already set

> 	beq	skip_sec_l2
> +	ldr	r0, =0x118			@ Setup L2 ACTLR = 0x118
> +	ldr	r12, =OMAP5_MON_L2AUX_CTRL_INDEX
I hope I am looking at the right place:
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0438g/BABIAICD.html
bit 3: Disable clean/evict push to external
bit 4: Disable WriteUnique and WriteLineUnique transactions from master
bit 8: Disable DVM/CMO message broadcast

Is'nt it better to configure on boot, save it into SAR memory and restore it
from SAR using monitor call? I mean it is possible that we start boot
with L2 ACTLR != 0x118 and then hit off and come out of OFF mode with
0x118.
One generally wants the system to be same before and after OFF/LP mode.
else, one tends to track bug such as
"At boot I see this bug, but after a while I dont see (cpuidle kicked in)"
- harder one to track down
or
"At boot I see this bug, but after a first suspend resume, I dont see (OFF kicked in)"
- easier one to track.
or vice versa and other combinations.. :(

> +	dsb
> +	smc     #0
DO_SMC ?
> +	dsb
> +skip_sec_l2:
>  	b	cpu_resume			@ Jump to generic resume
Santosh Shilimkar March 2, 2013, 6:24 a.m. UTC | #2
On Saturday 02 March 2013 05:13 AM, Nishanth Menon wrote:
> On 17:41-20130301, Santosh Shilimkar wrote:
>> 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.
>>
>> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
>> ---
>>  arch/arm/mach-omap2/omap-secure.h     |    1 +
>>  arch/arm/mach-omap2/sleep_omap4plus.S |   30 ++++++++++++++++++++++++++++++
>>  2 files changed, 31 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
>>  
>>  #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 f4874e5..ea318be 100644
>> --- a/arch/arm/mach-omap2/sleep_omap4plus.S
>> +++ b/arch/arm/mach-omap2/sleep_omap4plus.S
>> @@ -386,6 +386,27 @@ 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
> umm, we store l2x0_pwrst_prepare(cpu, save_state);
> which in turn stores into L2X0_SAVE_OFFSET - I am with you so far
> save_state in omap4_enter_lowpower is:
> PWRDM_POWER_INACTIVE: 0
> PWRDM_POWER_OFF: 1
> or 2 in the case of OSWR
> what is 3? ref:
> https://github.com/SantoshShilimkar/linux/blob/testing/3.10/omap5-int-rebuild/arch/arm/mach-omap2/omap-mpuss-lowpower.c#L298
This was obviosly for the case where L2 can be destroyed. As I said it can happen
with MPU OSWR + L2 OFF setting or device OFF. 

>> +	bne	do_wfi
>> +	bl	omap4_get_sar_ram_base
>> +	ldr	r9, [r0, #OMAP_TYPE_OFFSET]
>> +	cmp	r9, #0x1			@ Check for HS device
> my 2c:
> off topic: somewhere down the line, I think we need to clear up these
> into macros so that as in this case, omap4_mpuss_init populated value
> should be the same as here with usage of same macro without reviewer
> needing to track down where it was set with what.
>
Patches welcome :)

 
>> +	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:
>> +	mov	r0, #2				@ Flush L2
> v7_flush_dcache_all does not take parameters, right?
>> +	bl	v7_flush_dcache_all
>> +
>>  do_wfi:
>>  	bl	omap_do_wfi
>>  
>> @@ -427,6 +448,15 @@ ENTRY(omap5_cpu_resume)
>>  	dsb
>>  1:
>>  #endif
>> +	mrc	p15, 1, r0, c15, c0, 0		@ Read L2 ACTLR
>> +	cmp	r0, #0x118			@ Check if it is already set
> 
>> 	beq	skip_sec_l2
>> +	ldr	r0, =0x118			@ Setup L2 ACTLR = 0x118
>> +	ldr	r12, =OMAP5_MON_L2AUX_CTRL_INDEX
> I hope I am looking at the right place:
> http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0438g/BABIAICD.html
It is correct.

> 
> Is'nt it better to configure on boot, save it into SAR memory and restore it
> from SAR using monitor call? I mean it is possible that we start boot
> with L2 ACTLR != 0x118 and then hit off and come out of OFF mode with
> 0x118.
No need because it is more of re-initing the value rather than save/restore.
I should have used macro instead of value though.

btw. I might drop this special setting based on some experiments am doing
with benchmarks. Either case, if I keep the L2AUX code, I will use
a macro.

Regards
Santosh


--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Nishanth Menon March 4, 2013, 6:41 p.m. UTC | #3
On 11:54-20130302, Santosh Shilimkar wrote:
> On Saturday 02 March 2013 05:13 AM, Nishanth Menon wrote:
> > On 17:41-20130301, Santosh Shilimkar wrote:
> >> 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.
> >>
> >> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
> >> ---
> >>  arch/arm/mach-omap2/omap-secure.h     |    1 +
> >>  arch/arm/mach-omap2/sleep_omap4plus.S |   30 ++++++++++++++++++++++++++++++
> >>  2 files changed, 31 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
> >>  
> >>  #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 f4874e5..ea318be 100644
> >> --- a/arch/arm/mach-omap2/sleep_omap4plus.S
> >> +++ b/arch/arm/mach-omap2/sleep_omap4plus.S
> >> @@ -386,6 +386,27 @@ 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
> > umm, we store l2x0_pwrst_prepare(cpu, save_state);
> > which in turn stores into L2X0_SAVE_OFFSET - I am with you so far
> > save_state in omap4_enter_lowpower is:
> > PWRDM_POWER_INACTIVE: 0
> > PWRDM_POWER_OFF: 1
> > or 2 in the case of OSWR
> > what is 3? ref:
> > https://github.com/SantoshShilimkar/linux/blob/testing/3.10/omap5-int-rebuild/arch/arm/mach-omap2/omap-mpuss-lowpower.c#L298
> This was obviosly for the case where L2 can be destroyed. As I said it can happen
> with MPU OSWR + L2 OFF setting or device OFF. 
Then please use macros for this.
> 
> >> +	bne	do_wfi
> >> +	bl	omap4_get_sar_ram_base
> >> +	ldr	r9, [r0, #OMAP_TYPE_OFFSET]
> >> +	cmp	r9, #0x1			@ Check for HS device
> > my 2c:
> > off topic: somewhere down the line, I think we need to clear up these
> > into macros so that as in this case, omap4_mpuss_init populated value
> > should be the same as here with usage of same macro without reviewer
> > needing to track down where it was set with what.
> >
> Patches welcome :)
Sure as long as we don't add even more "magic handshakes to the code" it
makes sense to cleanup older code.
> 
>  
> >> +	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:
> >> +	mov	r0, #2				@ Flush L2
> > v7_flush_dcache_all does not take parameters, right?
> >> +	bl	v7_flush_dcache_all
> >> +
> >>  do_wfi:
> >>  	bl	omap_do_wfi
> >>  
> >> @@ -427,6 +448,15 @@ ENTRY(omap5_cpu_resume)
> >>  	dsb
> >>  1:
> >>  #endif
> >> +	mrc	p15, 1, r0, c15, c0, 0		@ Read L2 ACTLR
> >> +	cmp	r0, #0x118			@ Check if it is already set
> > 
> >> 	beq	skip_sec_l2
> >> +	ldr	r0, =0x118			@ Setup L2 ACTLR = 0x118
> >> +	ldr	r12, =OMAP5_MON_L2AUX_CTRL_INDEX
> > I hope I am looking at the right place:
> > http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0438g/BABIAICD.html
> It is correct.
> 
> > 
> > Is'nt it better to configure on boot, save it into SAR memory and restore it
> > from SAR using monitor call? I mean it is possible that we start boot
> > with L2 ACTLR != 0x118 and then hit off and come out of OFF mode with
> > 0x118.
> No need because it is more of re-initing the value rather than save/restore.
> I should have used macro instead of value though.
> 
> btw. I might drop this special setting based on some experiments am doing
> with benchmarks. Either case, if I keep the L2AUX code, I will use
> a macro.
Thanks. As long as it remains constant at boot and across OFF, it is
fine with me.
diff mbox

Patch

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
 
 #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 f4874e5..ea318be 100644
--- a/arch/arm/mach-omap2/sleep_omap4plus.S
+++ b/arch/arm/mach-omap2/sleep_omap4plus.S
@@ -386,6 +386,27 @@  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:
+	mov	r0, #2				@ Flush L2
+	bl	v7_flush_dcache_all
+
 do_wfi:
 	bl	omap_do_wfi
 
@@ -427,6 +448,15 @@  ENTRY(omap5_cpu_resume)
 	dsb
 1:
 #endif
+	mrc	p15, 1, r0, c15, c0, 0		@ Read L2 ACTLR
+	cmp	r0, #0x118			@ Check if it is already set
+	beq	skip_sec_l2
+	ldr	r0, =0x118			@ Setup L2 ACTLR = 0x118
+	ldr	r12, =OMAP5_MON_L2AUX_CTRL_INDEX
+	dsb
+	smc     #0
+	dsb
+skip_sec_l2:
 	b	cpu_resume			@ Jump to generic resume
 ENDPROC(omap5_cpu_resume)
 #endif