Re: [edk2-devel] [PATCH edk2-platforms 2/3] Platform/ARM/JunoPkg: Override PcdTimerPeriod to be 10000

["Rebecca Cran" <quic_rcran@quicinc.com>]

On 12/5/22 02:22, Pierre Gondois wrote:

> The default value of PcdTimerPeriod in EmbeddedPkg/EmbeddedPkg.dec
> seems to be 100000 (100ns), so 10ms, and other Arm platforms have
> set the value to 1000 (100ns), so 100us. I was wondering where you
> found the 1ms value ?

Sorry, I misread a comment in TimerDxe.c. This patch should be dropped.

// mTimerTicks = TimerPeriod in 1ms unit * Frequency.10^-3

-- 
Rebecca Cran

> 
> Otherwise the other patches look good to me.
> 
> Regards,
> Pierre
> 
> 
> On 11/29/22 14:53, Rebecca Cran via groups.io wrote:
>> The PCD PcdTimerPeriod is used in TimerDxe to calculate how many ticks
>> to wait between timer interrupts. The default value of 100000 results
>> in waiting 10 ms, while the driver wants interrupts to occur every 1ms.
>>
>> Override the value of PcdTimerPeriod in ArmJuno.dsc to be 10000.
>>
>> Signed-off-by: Rebecca Cran <rebecca@quicinc.com>
>> ---
>>   Platform/ARM/JunoPkg/ArmJuno.dsc | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/Platform/ARM/JunoPkg/ArmJuno.dsc 
>> b/Platform/ARM/JunoPkg/ArmJuno.dsc
>> index 9cde4c862651..9b63a8914f03 100644
>> --- a/Platform/ARM/JunoPkg/ArmJuno.dsc
>> +++ b/Platform/ARM/JunoPkg/ArmJuno.dsc
>> @@ -189,6 +189,7 @@ [PcdsFixedAtBuild.common]
>>     # ARM Architectural Timer Frequency
>>     #
>>     gArmTokenSpaceGuid.PcdArmArchTimerFreqInHz|50000000
>> +  gEmbeddedTokenSpaceGuid.PcdTimerPeriod|10000
>>     
>> gEfiMdeModulePkgTokenSpaceGuid.PcdResetOnMemoryTypeInformationChange|FALSE