[libcamera-devel] [RFC PATCH v2 1/3] ipa: ipu3: Separate out frame context queue as a distinct class

[paul.elder at ideasonboard.com]

Hi Umang,

On Fri, May 27, 2022 at 09:17:38PM +0200, Umang Jain via libcamera-devel wrote:
> There are cases where we need more checks and balance to be carried out
> by the frame context queue class. For that, separate it out as a
> distinct class on which we can build upon.
> 
> For now, a minimialistic implementation is provided with .get(frame)
> helper which returns a IPAFrameContext for the required frame.
> Going ahead more such helpers can be provided to access/modify the
> frame context queue.
> 
> Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>

Reviewed-by: Paul Elder <paul.elder at ideasonboard.com>

> ---
>  src/ipa/ipu3/ipa_context.cpp | 49 ++++++++++++++++++++++++++++++++++--
>  src/ipa/ipu3/ipa_context.h   | 11 +++++++-
>  src/ipa/ipu3/ipu3.cpp        |  6 ++---
>  3 files changed, 60 insertions(+), 6 deletions(-)
> 
> diff --git a/src/ipa/ipu3/ipa_context.cpp b/src/ipa/ipu3/ipa_context.cpp
> index 13cdb835..e5010e3f 100644
> --- a/src/ipa/ipu3/ipa_context.cpp
> +++ b/src/ipa/ipu3/ipa_context.cpp
> @@ -7,12 +7,18 @@
>  
>  #include "ipa_context.h"
>  
> +#include <libcamera/base/log.h>
> +
>  /**
>   * \file ipa_context.h
>   * \brief Context and state information shared between the algorithms
>   */
>  
> -namespace libcamera::ipa::ipu3 {
> +namespace libcamera {
> +
> +LOG_DECLARE_CATEGORY(IPAIPU3)
> +
> +namespace ipa::ipu3 {
>  
>  /**
>   * \struct IPASessionConfiguration
> @@ -211,4 +217,43 @@ IPAFrameContext::IPAFrameContext(uint32_t id, const ControlList &reqControls)
>   * \brief Analogue gain multiplier
>   */
>  
> -} /* namespace libcamera::ipa::ipu3 */
> +/**
> + * \brief FCQueue constructor
> + */
> +FCQueue::FCQueue()
> +{
> +	clear();
> +}
> +
> +/**
> + * Retrieve the IPAFrameContext for the frame
> + * \param[in] frame Frame number for which the IPAFrameContext needs to
> + * retrieved
> + *
> + * \return Reference to the IPAFrameContext
> + */
> +IPAFrameContext &FCQueue::get(uint32_t frame)
> +{
> +	IPAFrameContext &frameContext = this->at(frame % kMaxFrameContexts);
> +
> +	if (frame != frameContext.frame) {
> +		LOG(IPAIPU3, Warning)
> +			<< "Got wrong frame context for frame" << frame
> +			<< " or frame context doesn't exist yet";
> +	}
> +
> +	return frameContext;
> +}
> +
> +/**
> + * \brief Clear the FCQueue by resetting all the entries in the ring-buffer
> + */
> +void FCQueue::clear()
> +{
> +	IPAFrameContext initFrameContext;
> +	this->fill(initFrameContext);
> +}
> +
> +} /* namespace ipa::ipu3 */
> +
> +} /* namespace libcamera */
> diff --git a/src/ipa/ipu3/ipa_context.h b/src/ipa/ipu3/ipa_context.h
> index 42e11141..61454b41 100644
> --- a/src/ipa/ipu3/ipa_context.h
> +++ b/src/ipa/ipu3/ipa_context.h
> @@ -89,11 +89,20 @@ struct IPAFrameContext {
>  	ControlList frameControls;
>  };
>  
> +class FCQueue : public std::array<IPAFrameContext, kMaxFrameContexts>
> +{
> +public:
> +	FCQueue();
> +
> +	void clear();
> +	IPAFrameContext &get(uint32_t frame);
> +};
> +
>  struct IPAContext {
>  	IPASessionConfiguration configuration;
>  	IPAActiveState activeState;
>  
> -	std::array<IPAFrameContext, kMaxFrameContexts> frameContexts;
> +	FCQueue frameContexts;
>  };
>  
>  } /* namespace ipa::ipu3 */
> diff --git a/src/ipa/ipu3/ipu3.cpp b/src/ipa/ipu3/ipu3.cpp
> index 2f6bb672..c48d2f62 100644
> --- a/src/ipa/ipu3/ipu3.cpp
> +++ b/src/ipa/ipu3/ipu3.cpp
> @@ -456,8 +456,8 @@ int IPAIPU3::configure(const IPAConfigInfo &configInfo,
>  
>  	/* Clean IPAActiveState at each reconfiguration. */
>  	context_.activeState = {};
> -	IPAFrameContext initFrameContext;
> -	context_.frameContexts.fill(initFrameContext);
> +	context_.frameContexts.clear();
> +
>  
>  	if (!validateSensorControls()) {
>  		LOG(IPAIPU3, Error) << "Sensor control validation failed.";
> @@ -569,7 +569,7 @@ void IPAIPU3::processStatsBuffer(const uint32_t frame,
>  	const ipu3_uapi_stats_3a *stats =
>  		reinterpret_cast<ipu3_uapi_stats_3a *>(mem.data());
>  
> -	IPAFrameContext &frameContext = context_.frameContexts[frame % kMaxFrameContexts];
> +	IPAFrameContext &frameContext = context_.frameContexts.get(frame);
>  
>  	if (frameContext.frame != frame)
>  		LOG(IPAIPU3, Warning) << "Frame " << frame << " does not match its frame context";
> -- 
> 2.31.1
>