media: Add VP9 v4l2 library

Provide code common to vp9 drivers in one central location.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

1 files changed, 233 insertions, 0 deletions

diff --git a/include/media/v4l2-vp9.h b/include/media/v4l2-vp9.h
new file mode 100644
index 000000000000..05478ad6d4ab
--- /dev/null
+++ b/include/media/v4l2-vp9.h
@@ -0,0 +1,233 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Helper functions for vp9 codecs.
+ *
+ * Copyright (c) 2021 Collabora, Ltd.
+ *
+ * Author: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
+ */
+
+#ifndef _MEDIA_V4L2_VP9_H
+#define _MEDIA_V4L2_VP9_H
+
+#include <media/v4l2-ctrls.h>
+
+/**
+ * struct v4l2_vp9_frame_mv_context - motion vector-related probabilities
+ *
+ * @joint: motion vector joint probabilities.
+ * @sign: motion vector sign probabilities.
+ * @classes: motion vector class probabilities.
+ * @class0_bit: motion vector class0 bit probabilities.
+ * @bits: motion vector bits probabilities.
+ * @class0_fr: motion vector class0 fractional bit probabilities.
+ * @fr: motion vector fractional bit probabilities.
+ * @class0_hp: motion vector class0 high precision fractional bit probabilities.
+ * @hp: motion vector high precision fractional bit probabilities.
+ *
+ * A member of v4l2_vp9_frame_context.
+ */
+struct v4l2_vp9_frame_mv_context {
+	u8 joint[3];
+	u8 sign[2];
+	u8 classes[2][10];
+	u8 class0_bit[2];
+	u8 bits[2][10];
+	u8 class0_fr[2][2][3];
+	u8 fr[2][3];
+	u8 class0_hp[2];
+	u8 hp[2];
+};
+
+/**
+ * struct v4l2_vp9_frame_context - frame probabilities, including motion-vector related
+ *
+ * @tx8: TX 8x8 probabilities.
+ * @tx16: TX 16x16 probabilities.
+ * @tx32: TX 32x32 probabilities.
+ * @coef: coefficient probabilities.
+ * @skip: skip probabilities.
+ * @inter_mode: inter mode probabilities.
+ * @interp_filter: interpolation filter probabilities.
+ * @is_inter: is inter-block probabilities.
+ * @comp_mode: compound prediction mode probabilities.
+ * @single_ref: single ref probabilities.
+ * @comp_ref: compound ref probabilities.
+ * @y_mode: Y prediction mode probabilities.
+ * @uv_mode: UV prediction mode probabilities.
+ * @partition: partition probabilities.
+ * @mv: motion vector probabilities.
+ *
+ * Drivers which need to keep track of frame context(s) can use this struct.
+ * The members correspond to probability tables, which are specified only implicitly in the
+ * vp9 spec. Section 10.5 "Default probability tables" contains all the types of involved
+ * tables, i.e. the actual tables are of the same kind, and when they are reset (which is
+ * mandated by the spec sometimes) they are overwritten with values from the default tables.
+ */
+struct v4l2_vp9_frame_context {
+	u8 tx8[2][1];
+	u8 tx16[2][2];
+	u8 tx32[2][3];
+	u8 coef[4][2][2][6][6][3];
+	u8 skip[3];
+	u8 inter_mode[7][3];
+	u8 interp_filter[4][2];
+	u8 is_inter[4];
+	u8 comp_mode[5];
+	u8 single_ref[5][2];
+	u8 comp_ref[5];
+	u8 y_mode[4][9];
+	u8 uv_mode[10][9];
+	u8 partition[16][3];
+
+	struct v4l2_vp9_frame_mv_context mv;
+};
+
+/**
+ * struct v4l2_vp9_frame_symbol_counts - pointers to arrays of symbol counts
+ *
+ * @partition: partition counts.
+ * @skip: skip counts.
+ * @intra_inter: is inter-block counts.
+ * @tx32p: TX32 counts.
+ * @tx16p: TX16 counts.
+ * @tx8p: TX8 counts.
+ * @y_mode: Y prediction mode counts.
+ * @uv_mode: UV prediction mode counts.
+ * @comp: compound prediction mode counts.
+ * @comp_ref: compound ref counts.
+ * @single_ref: single ref counts.
+ * @mv_mode: inter mode counts.
+ * @filter: interpolation filter counts.
+ * @mv_joint: motion vector joint counts.
+ * @sign: motion vector sign counts.
+ * @classes: motion vector class counts.
+ * @class0: motion vector class0 bit counts.
+ * @bits: motion vector bits counts.
+ * @class0_fp: motion vector class0 fractional bit counts.
+ * @fp: motion vector fractional bit counts.
+ * @class0_hp: motion vector class0 high precision fractional bit counts.
+ * @hp: motion vector high precision fractional bit counts.
+ * @coeff: coefficient counts.
+ * @eob: eob counts
+ *
+ * The fields correspond to what is specified in section 8.3 "Clear counts process" of the spec.
+ * Different pieces of hardware can report the counts in different order, so we cannot rely on
+ * simply overlaying a struct on a relevant block of memory. Instead we provide pointers to
+ * arrays or array of pointers to arrays in case of coeff, or array of pointers for eob.
+ */
+struct v4l2_vp9_frame_symbol_counts {
+	u32 (*partition)[16][4];
+	u32 (*skip)[3][2];
+	u32 (*intra_inter)[4][2];
+	u32 (*tx32p)[2][4];
+	u32 (*tx16p)[2][4];
+	u32 (*tx8p)[2][2];
+	u32 (*y_mode)[4][10];
+	u32 (*uv_mode)[10][10];
+	u32 (*comp)[5][2];
+	u32 (*comp_ref)[5][2];
+	u32 (*single_ref)[5][2][2];
+	u32 (*mv_mode)[7][4];
+	u32 (*filter)[4][3];
+	u32 (*mv_joint)[4];
+	u32 (*sign)[2][2];
+	u32 (*classes)[2][11];
+	u32 (*class0)[2][2];
+	u32 (*bits)[2][10][2];
+	u32 (*class0_fp)[2][2][4];
+	u32 (*fp)[2][4];
+	u32 (*class0_hp)[2][2];
+	u32 (*hp)[2][2];
+	u32 (*coeff[4][2][2][6][6])[3];
+	u32 *eob[4][2][2][6][6][2];
+};
+
+extern const u8 v4l2_vp9_kf_y_mode_prob[10][10][9]; /* Section 10.4 of the spec */
+extern const u8 v4l2_vp9_kf_partition_probs[16][3]; /* Section 10.4 of the spec */
+extern const u8 v4l2_vp9_kf_uv_mode_prob[10][9]; /* Section 10.4 of the spec */
+extern const struct v4l2_vp9_frame_context v4l2_vp9_default_probs; /* Section 10.5 of the spec */
+
+/**
+ * v4l2_vp9_fw_update_probs() - Perform forward update of vp9 probabilities
+ *
+ * @probs: current probabilities values
+ * @deltas: delta values from compressed header
+ * @dec_params: vp9 frame decoding parameters
+ *
+ * This function performs forward updates of probabilities for the vp9 boolean decoder.
+ * The frame header can contain a directive to update the probabilities (deltas), if so, then
+ * the deltas are provided in the header, too. The userspace parses those and passes the said
+ * deltas struct to the kernel.
+ */
+void v4l2_vp9_fw_update_probs(struct v4l2_vp9_frame_context *probs,
+			      const struct v4l2_ctrl_vp9_compressed_hdr *deltas,
+			      const struct v4l2_ctrl_vp9_frame *dec_params);
+
+/**
+ * v4l2_vp9_reset_frame_ctx() - Reset appropriate frame context
+ *
+ * @dec_params: vp9 frame decoding parameters
+ * @frame_context: array of the 4 frame contexts
+ *
+ * This function resets appropriate frame contexts, based on what's in dec_params.
+ *
+ * Returns the frame context index after the update, which might be reset to zero if
+ * mandated by the spec.
+ */
+u8 v4l2_vp9_reset_frame_ctx(const struct v4l2_ctrl_vp9_frame *dec_params,
+			    struct v4l2_vp9_frame_context *frame_context);
+
+/**
+ * v4l2_vp9_adapt_coef_probs() - Perform backward update of vp9 coefficients probabilities
+ *
+ * @probs: current probabilities values
+ * @counts: values of symbol counts after the current frame has been decoded
+ * @use_128: flag to request that 128 is used as update factor if true, otherwise 112 is used
+ * @frame_is_intra: flag indicating that FrameIsIntra is true
+ *
+ * This function performs backward updates of coefficients probabilities for the vp9 boolean
+ * decoder. After a frame has been decoded the counts of how many times a given symbol has
+ * occurred are known and are used to update the probability of each symbol.
+ */
+void v4l2_vp9_adapt_coef_probs(struct v4l2_vp9_frame_context *probs,
+			       struct v4l2_vp9_frame_symbol_counts *counts,
+			       bool use_128,
+			       bool frame_is_intra);
+
+/**
+ * v4l2_vp9_adapt_noncoef_probs() - Perform backward update of vp9 non-coefficients probabilities
+ *
+ * @probs: current probabilities values
+ * @counts: values of symbol counts after the current frame has been decoded
+ * @reference_mode: specifies the type of inter prediction to be used. See
+ *	&v4l2_vp9_reference_mode for more details
+ * @interpolation_filter: specifies the filter selection used for performing inter prediction.
+ *	See &v4l2_vp9_interpolation_filter for more details
+ * @tx_mode: specifies the TX mode. See &v4l2_vp9_tx_mode for more details
+ * @flags: combination of V4L2_VP9_FRAME_FLAG_* flags
+ *
+ * This function performs backward updates of non-coefficients probabilities for the vp9 boolean
+ * decoder. After a frame has been decoded the counts of how many times a given symbol has
+ * occurred are known and are used to update the probability of each symbol.
+ */
+void v4l2_vp9_adapt_noncoef_probs(struct v4l2_vp9_frame_context *probs,
+				  struct v4l2_vp9_frame_symbol_counts *counts,
+				  u8 reference_mode, u8 interpolation_filter, u8 tx_mode,
+				  u32 flags);
+
+/**
+ * v4l2_vp9_seg_feat_enabled() - Check if a segmentation feature is enabled
+ *
+ * @feature_enabled: array of 8-bit flags (for all segments)
+ * @feature: id of the feature to check
+ * @segid: id of the segment to look up
+ *
+ * This function returns true if a given feature is active in a given segment.
+ */
+bool
+v4l2_vp9_seg_feat_enabled(const u8 *feature_enabled,
+			  unsigned int feature,
+			  unsigned int segid);
+
+#endif /* _MEDIA_V4L2_VP9_H */