| Message ID | 20230323012929.10815-7-dipenp@nvidia.com |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | Add Tegra234 HTE support | expand |
On 3/23/23 08:29, Dipen Patel wrote: > Make Tegra194 API document generic to make it applicable for > current and future tegra hte providers. > > Signed-off-by: Dipen Patel <dipenp@nvidia.com> > --- > Documentation/driver-api/hte/tegra194-hte.rst | 33 +++++++++---------- > 1 file changed, 16 insertions(+), 17 deletions(-) > While generalizing the doc, the doc file name should also be renamed (i.e. to tegra-hte.rst). > diff --git a/Documentation/driver-api/hte/tegra194-hte.rst b/Documentation/driver-api/hte/tegra194-hte.rst > index f2d617265546..85e654772782 100644 > --- a/Documentation/driver-api/hte/tegra194-hte.rst > +++ b/Documentation/driver-api/hte/tegra194-hte.rst > @@ -5,25 +5,25 @@ HTE Kernel provider driver > > Description > ----------- > -The Nvidia tegra194 HTE provider driver implements two GTE > -(Generic Timestamping Engine) 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: 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. > > GPIO GTE > -------- > > This GTE instance timestamps GPIO in real time. For that to happen GPIO > -needs to be configured as input. The always on (AON) GPIO controller instance > -supports timestamping GPIOs in real time and it has 39 GPIO lines. The GPIO GTE > -and AON GPIO controller are tightly coupled as it requires very specific bits > -to be set in GPIO config register before GPIO GTE can be used, for that GPIOLIB > -adds two optional APIs as 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. > +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. > > See gpiod_enable_hw_timestamp_ns() and gpiod_disable_hw_timestamp_ns(). > > @@ -34,9 +34,8 @@ returns the timestamp in nanoseconds. > LIC (Legacy Interrupt Controller) IRQ GTE > ----------------------------------------- > > -This GTE instance timestamps LIC IRQ lines in real time. There are 352 IRQ > -lines which this instance can add timestamps to in real time. The hte > -devicetree binding described at ``Documentation/devicetree/bindings/timestamp`` > +This GTE instance timestamps LIC IRQ lines in real time. The hte devicetree > +binding described at ``Documentation/devicetree/bindings/timestamp`` > provides an example of how a consumer can request an IRQ line. Since it is a > one-to-one mapping with IRQ GTE provider, consumers can simply specify the IRQ > number that they are interested in. There is no userspace consumer support for The wording LGTM, thanks! Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
On 4/4/23 7:24 PM, Bagas Sanjaya wrote: > On 3/23/23 08:29, Dipen Patel wrote: >> Make Tegra194 API document generic to make it applicable for >> current and future tegra hte providers. >> >> Signed-off-by: Dipen Patel <dipenp@nvidia.com> >> --- >> Documentation/driver-api/hte/tegra194-hte.rst | 33 +++++++++---------- >> 1 file changed, 16 insertions(+), 17 deletions(-) >> > > While generalizing the doc, the doc file name should also be renamed > (i.e. to tegra-hte.rst). make sense, I will do rename it in the next patch series. > >> diff --git a/Documentation/driver-api/hte/tegra194-hte.rst b/Documentation/driver-api/hte/tegra194-hte.rst >> index f2d617265546..85e654772782 100644 >> --- a/Documentation/driver-api/hte/tegra194-hte.rst >> +++ b/Documentation/driver-api/hte/tegra194-hte.rst >> @@ -5,25 +5,25 @@ HTE Kernel provider driver >> >> Description >> ----------- >> -The Nvidia tegra194 HTE provider driver implements two GTE >> -(Generic Timestamping Engine) 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: 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. >> >> GPIO GTE >> -------- >> >> This GTE instance timestamps GPIO in real time. For that to happen GPIO >> -needs to be configured as input. The always on (AON) GPIO controller instance >> -supports timestamping GPIOs in real time and it has 39 GPIO lines. The GPIO GTE >> -and AON GPIO controller are tightly coupled as it requires very specific bits >> -to be set in GPIO config register before GPIO GTE can be used, for that GPIOLIB >> -adds two optional APIs as 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. >> +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. >> >> See gpiod_enable_hw_timestamp_ns() and gpiod_disable_hw_timestamp_ns(). >> >> @@ -34,9 +34,8 @@ returns the timestamp in nanoseconds. >> LIC (Legacy Interrupt Controller) IRQ GTE >> ----------------------------------------- >> >> -This GTE instance timestamps LIC IRQ lines in real time. There are 352 IRQ >> -lines which this instance can add timestamps to in real time. The hte >> -devicetree binding described at ``Documentation/devicetree/bindings/timestamp`` >> +This GTE instance timestamps LIC IRQ lines in real time. The hte devicetree >> +binding described at ``Documentation/devicetree/bindings/timestamp`` >> provides an example of how a consumer can request an IRQ line. Since it is a >> one-to-one mapping with IRQ GTE provider, consumers can simply specify the IRQ >> number that they are interested in. There is no userspace consumer support for > > The wording LGTM, thanks! > > Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> >
diff --git a/Documentation/driver-api/hte/tegra194-hte.rst b/Documentation/driver-api/hte/tegra194-hte.rst index f2d617265546..85e654772782 100644 --- a/Documentation/driver-api/hte/tegra194-hte.rst +++ b/Documentation/driver-api/hte/tegra194-hte.rst @@ -5,25 +5,25 @@ HTE Kernel provider driver Description ----------- -The Nvidia tegra194 HTE provider driver implements two GTE -(Generic Timestamping Engine) 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: 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. GPIO GTE -------- This GTE instance timestamps GPIO in real time. For that to happen GPIO -needs to be configured as input. The always on (AON) GPIO controller instance -supports timestamping GPIOs in real time and it has 39 GPIO lines. The GPIO GTE -and AON GPIO controller are tightly coupled as it requires very specific bits -to be set in GPIO config register before GPIO GTE can be used, for that GPIOLIB -adds two optional APIs as 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. +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. See gpiod_enable_hw_timestamp_ns() and gpiod_disable_hw_timestamp_ns(). @@ -34,9 +34,8 @@ returns the timestamp in nanoseconds. LIC (Legacy Interrupt Controller) IRQ GTE ----------------------------------------- -This GTE instance timestamps LIC IRQ lines in real time. There are 352 IRQ -lines which this instance can add timestamps to in real time. The hte -devicetree binding described at ``Documentation/devicetree/bindings/timestamp`` +This GTE instance timestamps LIC IRQ lines in real time. The hte devicetree +binding described at ``Documentation/devicetree/bindings/timestamp`` provides an example of how a consumer can request an IRQ line. Since it is a one-to-one mapping with IRQ GTE provider, consumers can simply specify the IRQ number that they are interested in. There is no userspace consumer support for
Make Tegra194 API document generic to make it applicable for current and future tegra hte providers. Signed-off-by: Dipen Patel <dipenp@nvidia.com> --- Documentation/driver-api/hte/tegra194-hte.rst | 33 +++++++++---------- 1 file changed, 16 insertions(+), 17 deletions(-)