lkml.org 
[lkml]   [2022]   [Nov]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH 5/7] hte: Re-phrase tegra API document
From
On 11/30/22 10:34, Dipen Patel wrote:
>> I think the wording can be better:
> I do not understand, can you please elaborate?

Exactly where? Please quote appropriate hunks from below where do you not
understand.

>>
>> ---- >8 ----
>>
>> diff --git a/Documentation/driver-api/hte/tegra194-hte.rst b/Documentation/driver-api/hte/tegra194-hte.rst
>> index 85e654772782c1..13c45bfc03a75e 100644
>> --- a/Documentation/driver-api/hte/tegra194-hte.rst
>> +++ b/Documentation/driver-api/hte/tegra194-hte.rst
>> @@ -5,11 +5,11 @@ HTE Kernel provider driver
>>
>> Description
>> -----------
>> -The Nvidia tegra HTE provider also known as GTE (Generic Timestamping Engine)
>> -driver implements two GTE instances: 1) GPIO GTE and 2) LIC
>> -(Legacy Interrupt Controller) IRQ GTE. Both GTE instances get the timestamp
>> -from the system counter TSC which has 31.25MHz clock rate, and the driver
>> -converts clock tick rate to nanoseconds before storing it as timestamp value.
>> +The Nvidia tegra HTE provider, also known as GTE (Generic Timestamping Engine)
>> +driver implements two GTE instances: GPIO GTE and LIC (Legacy Interrupt
>> +Controller) IRQ GTE. Both GTE instances get the timestamp from system counter
>> +TSC which has 31.25MHz clock rate, and the driver converts clock tick rate to
>> +nanoseconds before storing it as timestamp value.
>>
>> GPIO GTE
>> --------
>> @@ -19,17 +19,17 @@ needs to be configured as input. Only the always on (AON) GPIO controller
>> instance supports timestamping GPIOs in real time as it is tightly coupled with
>> the GPIO GTE. To support this, GPIOLIB adds two optional APIs as mentioned
>> below. The GPIO GTE code supports both kernel and userspace consumers. The
>> -kernel space consumers can directly talk to HTE subsystem while userspace
>> -consumers timestamp requests go through GPIOLIB CDEV framework to HTE
>> -subsystem. The hte devicetree binding described at
>> -``Documentation/devicetree/bindings/timestamp`` provides an example of how a
>> -consumer can request an GPIO line.
>> +kernel space consumers can directly talk to HTE subsystem while requests from
>> +userspace consumers go through GPIOLIB CDEV framework to HTE subsystem. The hte
>> +devicetree binding described at ``Documentation/devicetree/bindings/timestamp``
>> +provides an example of how a consumer can request an GPIO line.
>>
>> -See gpiod_enable_hw_timestamp_ns() and gpiod_disable_hw_timestamp_ns().
>> +To toggle hardware timestamp, use gpiod_enable_hw_timestamp_ns() and
>> +gpiod_disable_hw_timestamp_ns().
>>
>> For userspace consumers, GPIO_V2_LINE_FLAG_EVENT_CLOCK_HTE flag must be
>> -specified during IOCTL calls. Refer to ``tools/gpio/gpio-event-mon.c``, which
>> -returns the timestamp in nanoseconds.
>> +specified during IOCTL calls. Refer to ``tools/gpio/gpio-event-mon.c`` for
>> +example.
>>
>> LIC (Legacy Interrupt Controller) IRQ GTE
>> -----------------------------------------
>>

Thanks anyway.

--
An old man doll... just what I always wanted! - Clara

\
 
 \ /
  Last update: 2022-11-30 04:46    [W:0.103 / U:1.540 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site