[RFC,v1] ipa: mali-c55: Add support for RGB Gamma

28723 diff mbox series

diff --git a/src/ipa/mali-c55/algorithms/gamma.cpp b/src/ipa/mali-c55/algorithms/gamma.cpp
new file mode 100644
index 0000000000..31cb45cfa5
--- /dev/null
+++ b/src/ipa/mali-c55/algorithms/gamma.cpp
@@ -0,0 +1,111 @@ 
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2026, Ideas On Board
+ *
+ * MaliC55 RGB Gamma control
+ */
+
+#include "gamma.h"
+
+#include <algorithm>
+
+#include <libcamera/controls.h>
+
+#include <libipa/fixedpoint.h>
+
+namespace libcamera {
+
+namespace ipa::mali_c55::algorithms {
+
+/**
+ * \class RGBGamma
+ * \brief MaliC55 Gamma out correction
+ *
+ * This algorithm implements the output gamma correction using the libipa
+ * GammaAlgorithm class.
+ *
+ * The hardware uses 129 evenly spaced points for its lookup table, and
+ * applies linear interpolation between them.
+ *
+ * The same module is also capable of applying an offset and gain to each channel.
+ * \todo Implement support for global contrast adjustments.
+ */
+
+/**
+ * \copydoc libcamera::ipa::Algorithm::init
+ */
+int RGBGamma::init(IPAContext &context, const ValueNode &tuningData)
+{
+	return gamma_.init(context.ctrlMap, tuningData);
+}
+
+/**
+ * \copydoc libcamera::ipa::Algorithm::configure
+ */
+int RGBGamma::configure(IPAContext &context,
+			[[maybe_unused]] const IPACameraSensorInfo &configInfo)
+{
+	gamma_.configure(context.activeState.gamma);
+
+	return 0;
+}
+
+/**
+ * \copydoc libcamera::ipa::Algorithm::queueRequest
+ */
+void RGBGamma::queueRequest(IPAContext &context, const uint32_t frame,
+			    IPAFrameContext &frameContext,
+			    const ControlList &controls)
+{
+	gamma_.queueRequest(context.activeState.gamma, frame, frameContext.gamma, controls);
+}
+
+/**
+ * \copydoc libcamera::ipa::Algorithm::prepare
+ */
+void RGBGamma::prepare([[maybe_unused]] IPAContext &context,
+		       [[maybe_unused]] const uint32_t frame,
+		       IPAFrameContext &frameContext,
+		       MaliC55Params *params)
+{
+	if (!frameContext.gamma.update)
+		return;
+
+	auto frConfig = params->block<MaliC55Blocks::GammaFr>();
+	frConfig.setEnabled(true);
+
+	gamma_.prepare(frameContext.gamma, std::span(frConfig->lut));
+
+	/*
+	 * Fixed offsets and gains: 0 and 1x.
+	 * \todo Implement global contrast adjustment using offsets and gains.
+	 */
+	std::fill(frConfig->gains, std::end(frConfig->gains), UQ<4, 8>(1.f).quantized());
+	std::fill(frConfig->offs, std::end(frConfig->offs), UQ<0, 12>(0.f).quantized());
+
+	/* Enable the same gamma correction on the "downscale" pipeline as well. */
+	auto dsConfig = params->block<MaliC55Blocks::GammaDs>();
+	dsConfig.setEnabled(true);
+
+	std::copy(frConfig->gains, std::end(frConfig->gains), dsConfig->gains);
+	std::copy(frConfig->offs, std::end(frConfig->offs), dsConfig->offs);
+	std::copy(frConfig->lut, std::end(frConfig->lut), dsConfig->lut);
+}
+
+/**
+ * \copydoc libcamera::ipa::Algorithm::process
+ */
+void RGBGamma::process([[maybe_unused]] IPAContext &context,
+		       [[maybe_unused]] const uint32_t frame,
+		       IPAFrameContext &frameContext,
+		       [[maybe_unused]] const mali_c55_stats_buffer *stats,
+		       ControlList &metadata)
+{
+	gamma_.process(frameContext.gamma, metadata);
+}
+
+REGISTER_IPA_ALGORITHM(RGBGamma, "RGBGamma")
+
+} /* namespace ipa::mali_c55::algorithms */
+
+} /* namespace libcamera */
diff --git a/src/ipa/mali-c55/algorithms/gamma.h b/src/ipa/mali-c55/algorithms/gamma.h
new file mode 100644
index 0000000000..d498ae6785
--- /dev/null
+++ b/src/ipa/mali-c55/algorithms/gamma.h
@@ -0,0 +1,42 @@ 
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2026, Ideas On Board
+ *
+ * MaliC55 RGB Gamma control
+ */
+
+#pragma once
+
+#include <libipa/fixedpoint.h>
+#include <libipa/gamma.h>
+
+#include "algorithm.h"
+
+namespace libcamera {
+
+namespace ipa::mali_c55::algorithms {
+
+class RGBGamma : public Algorithm
+{
+public:
+	int init(IPAContext &context, const ValueNode &tuningData) override;
+	int configure(IPAContext &context,
+		      const IPACameraSensorInfo &configInfo) override;
+	void queueRequest(IPAContext &context,
+			  const uint32_t frame,
+			  IPAFrameContext &frameContext,
+			  const ControlList &controls) override;
+	void prepare(IPAContext &context, const uint32_t frame,
+		     IPAFrameContext &frameContext,
+		     MaliC55Params *params) override;
+	void process(IPAContext &context, const uint32_t frame,
+		     IPAFrameContext &frameContext,
+		     const mali_c55_stats_buffer *stats,
+		     ControlList &metadata) override;
+
+private:
+	GammaAlgorithm<129, UQ<0, 12>> gamma_;
+};
+
+} /* namespace ipa::mali_c55::algorithms */
+} /* namespace libcamera */
diff --git a/src/ipa/mali-c55/algorithms/meson.build b/src/ipa/mali-c55/algorithms/meson.build
index 24a27ce665..65fb1baba9 100644
--- a/src/ipa/mali-c55/algorithms/meson.build
+++ b/src/ipa/mali-c55/algorithms/meson.build
@@ -5,5 +5,6 @@  mali_c55_ipa_algorithms = files([
     'awb.cpp',
     'blc.cpp',
     'ccm.cpp',
+    'gamma.cpp',
     'lsc.cpp',
 ])
diff --git a/src/ipa/mali-c55/data/uncalibrated.yaml b/src/ipa/mali-c55/data/uncalibrated.yaml
index ea44c58c9e..f4508fb913 100644
--- a/src/ipa/mali-c55/data/uncalibrated.yaml
+++ b/src/ipa/mali-c55/data/uncalibrated.yaml
@@ -7,4 +7,5 @@  algorithms:
   - Awb:
   - BlackLevelCorrection:
   - Ccm:
+  - RGBGamma:
 ...
diff --git a/src/ipa/mali-c55/ipa_context.h b/src/ipa/mali-c55/ipa_context.h
index cd370e25fc..030e0052ad 100644
--- a/src/ipa/mali-c55/ipa_context.h
+++ b/src/ipa/mali-c55/ipa_context.h
@@ -21,6 +21,7 @@ 
 #include "libipa/awb.h"
 #include "libipa/ccm.h"
 #include "libipa/fixedpoint.h"
+#include "libipa/gamma.h"
 #include "libipa/lsc.h"
 
 namespace libcamera {
@@ -43,6 +44,7 @@  struct IPAActiveState {
 
 	ipa::awb::ActiveState awb;
 	ipa::ccm::ActiveState ccm;
+	ipa::gamma::ActiveState gamma;
 	ipa::lsc::ActiveState lsc;
 };
 
@@ -56,6 +58,7 @@  struct IPAFrameContext : public FrameContext {
 
 	ipa::awb::FrameContext awb;
 	ipa::ccm::FrameContext ccm;
+	ipa::gamma::FrameContext gamma;
 	ipa::lsc::FrameContext lsc;
 };
 
diff --git a/src/ipa/mali-c55/params.h b/src/ipa/mali-c55/params.h
index dc4d199402..00c388c9ed 100644
--- a/src/ipa/mali-c55/params.h
+++ b/src/ipa/mali-c55/params.h
@@ -30,6 +30,8 @@  enum class MaliC55Blocks : uint16_t {
 	MeshShadingConfig,
 	MeshShadingSel,
 	Ccm,
+	GammaFr,
+	GammaDs,
 };
 
 namespace details {
@@ -57,6 +59,8 @@  MALI_C55_DEFINE_BLOCK_TYPE(AwbConfig,		awb_config,		BLOCK_AWB_CONFIG);
 MALI_C55_DEFINE_BLOCK_TYPE(MeshShadingConfig,	mesh_shading_config,	MESH_SHADING_CONFIG);
 MALI_C55_DEFINE_BLOCK_TYPE(MeshShadingSel,	mesh_shading_selection,	MESH_SHADING_SELECTION);
 MALI_C55_DEFINE_BLOCK_TYPE(Ccm,			ccm,			BLOCK_CCM);
+MALI_C55_DEFINE_BLOCK_TYPE(GammaFr,		gamma,			BLOCK_GAMMA_FR);
+MALI_C55_DEFINE_BLOCK_TYPE(GammaDs,		gamma,			BLOCK_GAMMA_DS);
 
 struct param_traits {
 	using id_type = MaliC55Blocks;