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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/misc/altera-stapl/altera-comp.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/misc/altera-stapl/altera-comp.c')
-rw-r--r-- | drivers/misc/altera-stapl/altera-comp.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/drivers/misc/altera-stapl/altera-comp.c b/drivers/misc/altera-stapl/altera-comp.c new file mode 100644 index 000000000..49b103bed --- /dev/null +++ b/drivers/misc/altera-stapl/altera-comp.c @@ -0,0 +1,142 @@ +/* + * altera-comp.c + * + * altera FPGA driver + * + * Copyright (C) Altera Corporation 1998-2001 + * Copyright (C) 2010 NetUP Inc. + * Copyright (C) 2010 Igor M. Liplianin <liplianin@netup.ru> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/kernel.h> +#include "altera-exprt.h" + +#define SHORT_BITS 16 +#define CHAR_BITS 8 +#define DATA_BLOB_LENGTH 3 +#define MATCH_DATA_LENGTH 8192 +#define ALTERA_REQUEST_SIZE 1024 +#define ALTERA_BUFFER_SIZE (MATCH_DATA_LENGTH + ALTERA_REQUEST_SIZE) + +static u32 altera_bits_req(u32 n) +{ + u32 result = SHORT_BITS; + + if (n == 0) + result = 1; + else { + /* Look for the highest non-zero bit position */ + while ((n & (1 << (SHORT_BITS - 1))) == 0) { + n <<= 1; + --result; + } + } + + return result; +} + +static u32 altera_read_packed(u8 *buffer, u32 bits, u32 *bits_avail, + u32 *in_index) +{ + u32 result = 0; + u32 shift = 0; + u32 databyte = 0; + + while (bits > 0) { + databyte = buffer[*in_index]; + result |= (((databyte >> (CHAR_BITS - *bits_avail)) + & (0xff >> (CHAR_BITS - *bits_avail))) << shift); + + if (bits <= *bits_avail) { + result &= (0xffff >> (SHORT_BITS - (bits + shift))); + *bits_avail -= bits; + bits = 0; + } else { + ++(*in_index); + shift += *bits_avail; + bits -= *bits_avail; + *bits_avail = CHAR_BITS; + } + } + + return result; +} + +u32 altera_shrink(u8 *in, u32 in_length, u8 *out, u32 out_length, s32 version) +{ + u32 i, j, data_length = 0L; + u32 offset, length; + u32 match_data_length = MATCH_DATA_LENGTH; + u32 bits_avail = CHAR_BITS; + u32 in_index = 0L; + + if (version > 0) + --match_data_length; + + for (i = 0; i < out_length; ++i) + out[i] = 0; + + /* Read number of bytes in data. */ + for (i = 0; i < sizeof(in_length); ++i) { + data_length = data_length | ( + altera_read_packed(in, + CHAR_BITS, + &bits_avail, + &in_index) << (i * CHAR_BITS)); + } + + if (data_length > out_length) { + data_length = 0L; + return data_length; + } + + i = 0; + while (i < data_length) { + /* A 0 bit indicates literal data. */ + if (altera_read_packed(in, 1, &bits_avail, + &in_index) == 0) { + for (j = 0; j < DATA_BLOB_LENGTH; ++j) { + if (i < data_length) { + out[i] = (u8)altera_read_packed(in, + CHAR_BITS, + &bits_avail, + &in_index); + i++; + } + } + } else { + /* A 1 bit indicates offset/length to follow. */ + offset = altera_read_packed(in, altera_bits_req((s16) + (i > match_data_length ? + match_data_length : i)), + &bits_avail, + &in_index); + length = altera_read_packed(in, CHAR_BITS, + &bits_avail, + &in_index); + for (j = 0; j < length; ++j) { + if (i < data_length) { + out[i] = out[i - offset]; + i++; + } + } + } + } + + return data_length; +} |