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media: hantro: Write the quantization tables in proper order
The quantization tables as defined in the file (luma_q_table,
chroma_q_table) are in fact in linear order. The JPEG file header, which is
not generated by the hardware, but must be programatically created with the
CPU, expects the table in zigzag order. On the other hand, the hardware
doesn't expect neither linear, nor zigzag order. Instead it expects the
quantization tables in vertical groups of four quantization parameters,
and the groups are organized in blocks of two vertically adjacent groups.
On top of that the blocks must be provided to the hardware in this order:
leftmost top block, leftmost bottom block, second leftmost top block,
second leftmost bottom block and so on. So, if this is the quantization
table in linear order:
0x10, 0x0b, 0x0a, 0x10, 0x18, 0x28, 0x33, 0x3d,
0x0c, 0x0c, 0x0e, 0x13, 0x1a, 0x3a, 0x3c, 0x37,
0x0e, 0x0d, 0x10, 0x18, 0x28, 0x39, 0x45, 0x38,
0x0e, 0x11, 0x16, 0x1d, 0x33, 0x57, 0x50, 0x3e,
0x12, 0x16, 0x25, 0x38, 0x44, 0x6d, 0x67, 0x4d,
0x18, 0x23, 0x37, 0x40, 0x51, 0x68, 0x71, 0x5c,
0x31, 0x40, 0x4e, 0x57, 0x67, 0x79, 0x78, 0x65,
0x48, 0x5c, 0x5f, 0x62, 0x70, 0x64, 0x67, 0x63
then the hardware expects this in its consecutive registers:
0x100c0e0e,
0x0b0c0d11,
0x12183148,
0x1623405c,
0x0a0e1016,
0x1013181d,
0x25374e5f,
0x38405762,
and so on.
Consequently, the same area of memory cannot be used both for dumping it
into the JPEG file header and writing its contents to the hardware
registers. Instead, a separate pair of arrays is added for properly
reordered quantization tables, to be read with get_unaligned_be32()
and linearly written to the registers.
The "ctx" parameter is not needed any more for hantro_jpeg_get_qtable().
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Tested-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>