From 0db2c8dc75e466e7648dc1b95380495c6a126349 Mon Sep 17 00:00:00 2001 From: Naushir Patuck Date: Sun, 3 May 2020 16:48:42 +0100 Subject: libcamera: ipa: Raspberry Pi IPA Initial implementation of the Raspberry Pi (BCM2835) libcamera IPA and associated libraries. All code is licensed under the BSD-2-Clause terms. Copyright (c) 2019-2020 Raspberry Pi Trading Ltd. Signed-off-by: Naushir Patuck Acked-by: Laurent Pinchart Signed-off-by: Laurent Pinchart --- src/ipa/raspberrypi/md_parser.cpp | 101 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 src/ipa/raspberrypi/md_parser.cpp (limited to 'src/ipa/raspberrypi/md_parser.cpp') diff --git a/src/ipa/raspberrypi/md_parser.cpp b/src/ipa/raspberrypi/md_parser.cpp new file mode 100644 index 00000000..ca809aa2 --- /dev/null +++ b/src/ipa/raspberrypi/md_parser.cpp @@ -0,0 +1,101 @@ +/* SPDX-License-Identifier: BSD-2-Clause */ +/* + * Copyright (C) 2019, Raspberry Pi (Trading) Limited + * + * md_parser.cpp - image sensor metadata parsers + */ + +#include +#include +#include + +#include "md_parser.hpp" + +using namespace RPi; + +// This function goes through the embedded data to find the offsets (not +// values!), in the data block, where the values of the given registers can +// subsequently be found. + +// Embedded data tag bytes, from Sony IMX219 datasheet but general to all SMIA +// sensors, I think. + +#define LINE_START 0x0a +#define LINE_END_TAG 0x07 +#define REG_HI_BITS 0xaa +#define REG_LOW_BITS 0xa5 +#define REG_VALUE 0x5a +#define REG_SKIP 0x55 + +MdParserSmia::ParseStatus MdParserSmia::findRegs(unsigned char *data, + uint32_t regs[], int offsets[], + unsigned int num_regs) +{ + assert(num_regs > 0); + if (data[0] != LINE_START) + return NO_LINE_START; + + unsigned int current_offset = 1; // after the LINE_START + unsigned int current_line_start = 0, current_line = 0; + unsigned int reg_num = 0, first_reg = 0; + ParseStatus retcode = PARSE_OK; + while (1) { + int tag = data[current_offset++]; + if ((bits_per_pixel_ == 10 && + (current_offset + 1 - current_line_start) % 5 == 0) || + (bits_per_pixel_ == 12 && + (current_offset + 1 - current_line_start) % 3 == 0)) { + if (data[current_offset++] != REG_SKIP) + return BAD_DUMMY; + } + int data_byte = data[current_offset++]; + //printf("Offset %u, tag 0x%02x data_byte 0x%02x\n", current_offset-1, tag, data_byte); + if (tag == LINE_END_TAG) { + if (data_byte != LINE_END_TAG) + return BAD_LINE_END; + if (num_lines_ && ++current_line == num_lines_) + return MISSING_REGS; + if (line_length_bytes_) { + current_offset = + current_line_start + line_length_bytes_; + // Require whole line to be in the buffer (if buffer size set). + if (buffer_size_bytes_ && + current_offset + line_length_bytes_ > + buffer_size_bytes_) + return MISSING_REGS; + if (data[current_offset] != LINE_START) + return NO_LINE_START; + } else { + // allow a zero line length to mean "hunt for the next line" + while (data[current_offset] != LINE_START && + current_offset < buffer_size_bytes_) + current_offset++; + if (current_offset == buffer_size_bytes_) + return NO_LINE_START; + } + // inc current_offset to after LINE_START + current_line_start = + current_offset++; + } else { + if (tag == REG_HI_BITS) + reg_num = (reg_num & 0xff) | (data_byte << 8); + else if (tag == REG_LOW_BITS) + reg_num = (reg_num & 0xff00) | data_byte; + else if (tag == REG_SKIP) + reg_num++; + else if (tag == REG_VALUE) { + while (reg_num >= + // assumes registers are in order... + regs[first_reg]) { + if (reg_num == regs[first_reg]) + offsets[first_reg] = + current_offset - 1; + if (++first_reg == num_regs) + return retcode; + } + reg_num++; + } else + return ILLEGAL_TAG; + } + } +} -- cgit v1.2.1