On Wednesday 18 September 2013 07:19 PM, Santosh Shilimkar wrote: > On Wednesday 18 September 2013 09:44 AM, Sricharan R wrote: >> On Wednesday 18 September 2013 07:01 PM, Santosh Shilimkar wrote: >>> On Wednesday 18 September 2013 07:23 AM, Sricharan R wrote: >>>> 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 >>>> host OS, as this will be propagated to the guests as well. >>>> >>> Its not host OS but ROM code/secure code. Host OS is not >>> ideal place to set it up. >> ok, so you are suggesting to re word this right ? >>>> 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@xxxxxxxxxxxxxxx/msg93832.html >>>> >>>> So configuring this secure register for all the cpus here. >>>> >>>> Cc: Santosh Shilimkar <santosh.shilimkar@xxxxxx> >>>> Cc: Nishanth Menon <nm@xxxxxx> >>>> Cc: Rajendra Nayak <rnayak@xxxxxx> >>>> Cc: Marc Zyngier <marc.zyngier@xxxxxxx> >>>> Cc: Mark Rutland <mark.rutland@xxxxxxx> >>>> Cc: Tony Lindgren <tony@xxxxxxxxxxx> >>>> Signed-off-by: Sricharan R <r.sricharan@xxxxxx> >>>> --- >>>> arch/arm/mach-omap2/omap-secure.h | 2 ++ >>>> arch/arm/mach-omap2/omap-smp.c | 9 +++++++++ >>>> arch/arm/mach-omap2/timer.c | 6 ++++++ >>>> 3 files changed, 17 insertions(+) >>>> >>>> diff --git a/arch/arm/mach-omap2/omap-secure.h b/arch/arm/mach-omap2/omap-secure.h >>>> index a171a5a..4de9a00 100644 >>>> --- a/arch/arm/mach-omap2/omap-secure.h >>>> +++ b/arch/arm/mach-omap2/omap-secure.h >>>> @@ -51,6 +51,8 @@ >>>> >>>> #define OMAP5_MON_AMBA_IF_INDEX 0x108 >>>> >>>> +#define OMAP5_DRA7_MON_SET_CNTFRQ_INDEX 0x109 >>>> + >>> Nice. Looks like OMAP5 ES2.0 addition which I missed. >>> >>>> /* Secure PPA(Primary Protected Application) APIs */ >>>> #define OMAP4_PPA_L2_POR_INDEX 0x23 >>>> #define OMAP4_PPA_CPU_ACTRL_SMP_INDEX 0x25 >>>> diff --git a/arch/arm/mach-omap2/omap-smp.c b/arch/arm/mach-omap2/omap-smp.c >>>> index 98a1146..00873b4 100644 >>>> --- a/arch/arm/mach-omap2/omap-smp.c >>>> +++ b/arch/arm/mach-omap2/omap-smp.c >>>> @@ -41,6 +41,8 @@ >>>> >>>> u16 pm44xx_errata; >>>> >>>> +extern unsigned long arch_timer_freq; >>>> + >>>> /* SCU base address */ >>>> static void __iomem *scu_base; >>>> >>>> @@ -66,6 +68,13 @@ static void __cpuinit omap4_secondary_init(unsigned int cpu) >>>> 4, 0, 0, 0, 0, 0); >>>> >>>> /* >>>> + * Configure the CNTFRQ register for the secondary cpu's which >>>> + * indicates the frequency of the cpu local timers. >>>> + */ >>>> + if (soc_is_omap54xx() || soc_is_dra7xx()) >>> CNTFREQ programming was not supported on OMAP5 ES1.0 and that was one >>> of the reason this parameter came into picture. So you need to skip >>> the ES1.0 here. >> We do not intend to support ES1.0 right ? . ok then id.c needs to be >> cleaned up to remove ES1.0 traces. > yes. With clean-up ES1.0, this can stay as is. > >>>> + omap_smc1(OMAP5_DRA7_MON_SET_CNTFRQ_INDEX, arch_timer_freq); >>>> + >>>> + /* >>>> * Synchronise with the boot thread. >>>> */ >>>> spin_lock(&boot_lock); >>>> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c >>>> index fd9238d..2c499f3 100644 >>>> --- a/arch/arm/mach-omap2/timer.c >>>> +++ b/arch/arm/mach-omap2/timer.c >>>> @@ -55,6 +55,7 @@ >>>> #include "soc.h" >>>> #include "common.h" >>>> #include "powerdomain.h" >>>> +#include "omap-secure.h" >>>> >>>> #define REALTIME_COUNTER_BASE 0x48243200 >>>> #define INCREMENTER_NUMERATOR_OFFSET 0x10 >>>> @@ -65,6 +66,7 @@ >>>> >>>> static struct omap_dm_timer clkev; >>>> static struct clock_event_device clockevent_gpt; >>>> +unsigned long arch_timer_freq; >>>> >>>> static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id) >>>> { >>>> @@ -546,7 +548,11 @@ static void __init realtime_counter_init(void) >>>> reg |= den; >>>> __raw_writel(reg, base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET); >>>> >>>> + arch_timer_freq = (rate / den) * num; >>>> + >>>> iounmap(base); >>>> + >>>> + omap_smc1(OMAP5_DRA7_MON_SET_CNTFRQ_INDEX, arch_timer_freq); >>> Few problems with this approach.. >>> >>> 1. CNTFREQ needs to be programmed on all CPUs. Even though arch-timer >>> code uses boot-cpu now thats not safe for guest which can start on >>> secondary CPUs. So please update this in secondary boot path as well. >> The patch is doing this for secondary cpu's as well in the >> call back omap4_secondary_init. >> > NM just pointed out this off-list. > > >>> 2. When you power cycle CPU, you will loose the value of this register >>> so you need to reprogram them on every CPU power up. Both DRA and OMAP5 >>> doesn't support that part yet but do remember to patch that when >>> such support gets added. >> oh ok. did not realize this. Will add the change for this then. > Since PM isn't supported for now, the patch looks alright with ES1.0 > support gets dropped. Just fix the change-log. > > Feel free to add my ack on updated version. Thanks. Will repost with the updated log and ack. Regards, Sricharan -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
