[libcamera-devel] [RFC PATCH 1/5] ipa: ipu3: Introduce a Context structure

[Jean-Michel Hautbois]

Passing parameters, statistics and all specific data each algorithm shares.
As the ipu3_uapi_params are part of the IPA context referenced by the
algorithms, move the structure into the IPAContext directly and adapt existing
algorithm implementations.

Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois at ideasonboard.com>
---
 src/ipa/ipu3/ipa_context.h | 30 ++++++++++++++++++++++++++++++
 src/ipa/ipu3/ipu3.cpp      | 16 +++++++++-------
 2 files changed, 39 insertions(+), 7 deletions(-)
 create mode 100644 src/ipa/ipu3/ipa_context.h

diff --git a/src/ipa/ipu3/ipa_context.h b/src/ipa/ipu3/ipa_context.h
new file mode 100644
index 00000000..5d717be5
--- /dev/null
+++ b/src/ipa/ipu3/ipa_context.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Ideas On Board
+ *
+ * ipu3_ipa_context.h - IPU3 IPA Context
+ *
+ * Context information shared between the algorithms
+ */
+#ifndef __LIBCAMERA_IPU3_IPA_CONTEXT_H__
+#define __LIBCAMERA_IPU3_IPA_CONTEXT_H__
+
+#include <linux/intel-ipu3.h>
+
+namespace libcamera {
+
+namespace ipa::ipu3 {
+
+struct IPAContext {
+	/* Input statistics from the previous frame */
+	const ipu3_uapi_stats_3a *stats;
+
+	/* Output Parameters which will be written to the hardware */
+	ipu3_uapi_params params;
+};
+
+} /* namespace ipa::ipu3 */
+
+} /* namespace libcamera*/
+
+#endif /* __LIBCAMERA_IPU3_IPA_CONTEXT_H__ */
diff --git a/src/ipa/ipu3/ipu3.cpp b/src/ipa/ipu3/ipu3.cpp
index 71698d36..a714af85 100644
--- a/src/ipa/ipu3/ipu3.cpp
+++ b/src/ipa/ipu3/ipu3.cpp
@@ -22,6 +22,8 @@
 
 #include "libcamera/internal/framebuffer.h"
 
+#include "ipa_context.h"
+
 #include "ipu3_agc.h"
 #include "ipu3_awb.h"
 #include "libipa/camera_sensor_helper.h"
@@ -81,9 +83,8 @@ private:
 	std::unique_ptr<CameraSensorHelper> camHelper_;
 
 	/* Local parameter storage */
-	struct ipu3_uapi_params params_;
-
 	struct ipu3_uapi_grid_config bdsGrid_;
+	struct IPAContext context_;
 };
 
 int IPAIPU3::init(const IPASettings &settings)
@@ -94,6 +95,9 @@ int IPAIPU3::init(const IPASettings &settings)
 		return -ENODEV;
 	}
 
+	/* Reset all the hardware settings */
+	context_.params = {};
+
 	return 0;
 }
 
@@ -193,12 +197,10 @@ int IPAIPU3::configure(const IPAConfigInfo &configInfo)
 
 	defVBlank_ = itVBlank->second.def().get<int32_t>();
 
-	params_ = {};
-
 	calculateBdsGrid(configInfo.bdsOutputSize);
 
 	awbAlgo_ = std::make_unique<IPU3Awb>();
-	awbAlgo_->initialise(params_, configInfo.bdsOutputSize, bdsGrid_);
+	awbAlgo_->initialise(context_.params, configInfo.bdsOutputSize, bdsGrid_);
 
 	agcAlgo_ = std::make_unique<IPU3Agc>();
 	agcAlgo_->initialise(bdsGrid_, sensorInfo_);
@@ -276,9 +278,9 @@ void IPAIPU3::processControls([[maybe_unused]] unsigned int frame,
 void IPAIPU3::fillParams(unsigned int frame, ipu3_uapi_params *params)
 {
 	if (agcAlgo_->updateControls())
-		awbAlgo_->updateWbParameters(params_, agcAlgo_->gamma());
+		awbAlgo_->updateWbParameters(context_.params, agcAlgo_->gamma());
 
-	*params = params_;
+	*params = context_.params;
 
 	IPU3Action op;
 	op.op = ActionParamFilled;
-- 
2.30.2