[PATCH V5] ARM: OMAP5/DRA7: realtime_counter: Configure CNTFRQ register
tony at atomide.com
Fri Oct 11 20:34:33 EDT 2013
* 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://firstname.lastname@example.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.
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>
@@ -66,12 +66,15 @@
static struct omap_dm_timer clkev;
static struct clock_event_device clockevent_gpt;
static unsigned long arch_timer_freq;
static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
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