ipa: rkisp1: Introduce IPAContext

Before using any algorithm, we want the IPAContext to be ready for
those. Introduce the IPAContext following the existing design from
IPA::IPU3. Each algorithm will then introduce the needed fields.

Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

src/ipa/rkisp1/ipa_context.cpp

@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Ideas On Board
+ *
+ * ipa_context.cpp - RkISP1 IPA Context
+ */
+
+#include "ipa_context.h"
+
+/**
+ * \file ipa_context.h
+ * \brief Context and state information shared between the algorithms
+ */
+
+namespace libcamera::ipa::rkisp1 {
+
+/**
+ * \struct IPASessionConfiguration
+ * \brief Session configuration for the IPA module
+ *
+ * The session configuration contains all IPA configuration parameters that
+ * remain constant during the capture session, from IPA module start to stop.
+ * It is typically set during the configure() operation of the IPA module, but
+ * may also be updated in the start() operation.
+ */
+
+/**
+ * \struct IPAFrameContext
+ * \brief Per-frame context for algorithms
+ *
+ * The frame context stores data specific to a single frame processed by the
+ * IPA. Each frame processed by the IPA has a context associated with it,
+ * accessible through the IPAContext structure.
+ *
+ * \todo Detail how to access contexts for a particular frame
+ *
+ * Each of the fields in the frame context belongs to either a specific
+ * algorithm, or to the top-level IPA module. A field may be read by any
+ * algorithm, but should only be written by its owner.
+ */
+
+/**
+ * \struct IPAContext
+ * \brief Global IPA context data shared between all algorithms
+ *
+ * \var IPAContext::configuration
+ * \brief The IPA session configuration, immutable during the session
+ *
+ * \var IPAContext::frameContext
+ * \brief The frame context for the frame being processed
+ *
+ * \todo While the frame context is supposed to be per-frame, this
+ * single frame context stores data related to both the current frame
+ * and the previous frames, with fields being updated as the algorithms
+ * are run. This needs to be turned into real per-frame data storage.
+ */
+
+} /* namespace libcamera::ipa::rkisp1 */

src/ipa/rkisp1/ipa_context.h

@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Ideas On Board
+ *
+ * ipa_context.h - RkISP1 IPA Context
+ *
+ */
+
+#pragma once
+
+namespace libcamera {
+
+namespace ipa::rkisp1 {
+
+struct IPASessionConfiguration {
+};
+
+struct IPAFrameContext {
+};
+
+struct IPAContext {
+	IPASessionConfiguration configuration;
+	IPAFrameContext frameContext;
+};
+
+} /* namespace ipa::rkisp1 */
+
+} /* namespace libcamera*/

src/ipa/rkisp1/meson.build

@@ -2,8 +2,13 @@
 
 ipa_name = 'ipa_rkisp1'
 
+rkisp1_ipa_sources = files([
+    'ipa_context.cpp',
+    'rkisp1.cpp',
+])
+
 mod = shared_module(ipa_name,
-                    ['rkisp1.cpp', libcamera_generated_ipa_headers],
+                    [rkisp1_ipa_sources, libcamera_generated_ipa_headers],
                     name_prefix : '',
                     include_directories : [ipa_includes, libipa_includes],
                     dependencies : libcamera_private,

src/ipa/rkisp1/rkisp1.cpp

@@ -25,6 +25,7 @@
 
 #include <libcamera/internal/mapped_framebuffer.h>
 
+#include "ipa_context.h"
 #include "libipa/camera_sensor_helper.h"
 
 namespace libcamera {
@@ -78,6 +79,9 @@ private:
 
 	/* Interface to the Camera Helper */
 	std::unique_ptr<CameraSensorHelper> camHelper_;
+
+	/* Local parameter storage */
+	struct IPAContext context_;
 };
 
 int IPARkISP1::init(const IPASettings &settings, unsigned int hwRevision)
@@ -164,6 +168,9 @@ int IPARkISP1::configure([[maybe_unused]] const IPACameraSensorInfo &info,
 		<< "Exposure: " << minExposure_ << "-" << maxExposure_
 		<< " Gain: " << minGain_ << "-" << maxGain_;
 
+	/* Clean context at configuration */
+	context_ = {};
+
 	return 0;
 }