[PATCH V5] ARM: OMAP5/DRA7: realtime_counter: Configure CNTFRQ register

Santosh Shilimkar santosh.shilimkar at ti.com
Fri Oct 11 20:37:05 EDT 2013

On Friday 11 October 2013 08:34 PM, Tony Lindgren wrote:
> * Tony Lindgren <tony at atomide.com> [131010 10:23]:
>> * Santosh Shilimkar <santosh.shilimkar at ti.com> [131010 06:20]:
>>> On Thursday 10 October 2013 03:43 AM, Sricharan R wrote:
>>>> From: R Sricharan <r.sricharan at ti.com>
>>>> The realtime counter called master counter, produces the count
>>>> used by the private timer peripherals in the MPU_CLUSTER. The
>>>> CNTFRQ per cpu register is used to denote the frequency of the counter.
>>>> Currently the frequency value is passed from the
>>>> DT file, but this is not scalable when we have other non-DT guest
>>>> OS. This register must be set to the right value by the
>>>> secure rom code. Setting this register helps in propagating the right
>>>> frequency value across OSes.
>>>> More discussions and the reason for adding this in a non-DT
>>>> way can be seen from below.
>>>> http://www.mail-archive.com/linux-omap@vger.kernel.org/msg93832.html
>>>> So configuring this secure register for all the cpus here.
>>>> Cc: Santosh Shilimkar <santosh.shilimkar at ti.com>
>>>> Cc: Nishanth Menon <nm at ti.com>
>>>> Cc: Rajendra Nayak <rnayak at ti.com>
>>>> Cc: Marc Zyngier <marc.zyngier at arm.com>
>>>> Cc: Mark Rutland <mark.rutland at arm.com>
>>>> Cc: Tony Lindgren <tony at atomide.com>
>>>> Tested-by: Nishanth Menon <nm at ti.com>
>>>> Acked-by: Santosh Shilimkar <santosh.shilimkar at ti.com>
>>>> Signed-off-by: Sricharan R <r.sricharan at ti.com>
>>>> ---
>>>>  [V5] Removed the use of extern variable in omap-smp.c
>>>>       as per suggestion from Santosh Shilimkar <santosh.shilimkar at ti.com>
>>> Thanks for the updates Sricharan. Looks fine now.
>>> Tony, Can you apply this version if you are fine with it.
>> Yes thanks looks good to me now. Applying into omap-for-v3.13/soc.
> Grr, had to apply the following fix on top of this for some configs.
Looks like Sricharan missed some builds. Sorry for the trouble Tony.

> 8< ---------------------------
> From: Tony Lindgren <tony at atomide.com>
> Date: Fri, 11 Oct 2013 17:28:04 -0700
> Subject: [PATCH] ARM: OMAP2+: Fix build error for realtime counter init if not enabled
> Otherwise we can get an error with some configs:
> arch/arm/mach-omap2/timer.c:73: undefined reference to `omap_smc1'
> Signed-off-by: Tony Lindgren <tony at atomide.com>
Looks fine to me. Thanks 


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