diff mbox series

[RFC,09/16] soundwire: crc8: add constant table

Message ID 20231207222944.663893-10-pierre-louis.bossart@linux.intel.com (mailing list archive)
State RFC
Headers show
Series soundwire/ASoC: speed-up downloads with BTP/BRA protocol | expand

Commit Message

Pierre-Louis Bossart Dec. 7, 2023, 10:29 p.m. UTC 
Add the lookup table required by crc8(). All configuration values were
directly table from the MIPI SoundWire 1.x specification.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
---
 drivers/soundwire/Makefile |   4 +-
 drivers/soundwire/crc8.c   | 277 +++++++++++++++++++++++++++++++++++++
 drivers/soundwire/crc8.h   |  11 ++
 3 files changed, 291 insertions(+), 1 deletion(-)
 create mode 100644 drivers/soundwire/crc8.c
 create mode 100644 drivers/soundwire/crc8.h

Comments

Vinod Koul Dec. 18, 2023, 12:01 p.m. UTC | #1 
On 07-12-23, 16:29, Pierre-Louis Bossart wrote:
> Add the lookup table required by crc8(). All configuration values were
> directly table from the MIPI SoundWire 1.x specification.
> 
> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
> ---
>  drivers/soundwire/Makefile |   4 +-
>  drivers/soundwire/crc8.c   | 277 +++++++++++++++++++++++++++++++++++++
>  drivers/soundwire/crc8.h   |  11 ++
>  3 files changed, 291 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/soundwire/crc8.c
>  create mode 100644 drivers/soundwire/crc8.h
> 
> diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile
> index 657f5888a77b..170128dd9318 100644
> --- a/drivers/soundwire/Makefile
> +++ b/drivers/soundwire/Makefile
> @@ -5,7 +5,9 @@
>  
>  #Bus Objs
>  soundwire-bus-y := bus_type.o bus.o master.o slave.o mipi_disco.o stream.o  \
> -			sysfs_slave.o sysfs_slave_dpn.o
> +			sysfs_slave.o sysfs_slave_dpn.o \
> +			crc8.o
> +
>  obj-$(CONFIG_SOUNDWIRE) += soundwire-bus.o
>  
>  soundwire-generic-allocation-objs := generic_bandwidth_allocation.o
> diff --git a/drivers/soundwire/crc8.c b/drivers/soundwire/crc8.c
> new file mode 100644
> index 000000000000..b6b984d7f39a
> --- /dev/null
> +++ b/drivers/soundwire/crc8.c
> @@ -0,0 +1,277 @@
> +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
> +// Copyright(c) 2024 Intel Corporation.
> +
> +#include <linux/crc8.h>
> +#include <linux/module.h>
> +#include "crc8.h"
> +
> +/*
> + * the MIPI SoundWire CRC8 polynomial is X^8 + X^6 + X^3 + X^2 + 1, MSB first
> + * The value is (1)01001101 = 0x4D
> + *
> + * the table below was generated with
> + *
> + *	u8 crc8_lookup_table[CRC8_TABLE_SIZE];
> + *	crc8_populate_msb(crc8_lookup_table, SDW_CRC8_POLY);

Good that you found this API, so next question would be why should we
have this static table in kernel and not generate on probe if bpt is
supported..? Many subsystems use these APIs to generate the tables..


> + *
> + */
> +
> +const u8 sdw_crc8_lookup_msb[CRC8_TABLE_SIZE] = {
> +	0x00, /* 0 */
> +	0x4d, /* 1 */
> +	0x9a, /* 2 */
> +	0xd7, /* 3 */
> +	0x79, /* 4 */
> +	0x34, /* 5 */
> +	0xe3, /* 6 */
> +	0xae, /* 7 */
> +	0xf2, /* 8 */
> +	0xbf, /* 9 */
> +	0x68, /* 10 */
> +	0x25, /* 11 */
> +	0x8b, /* 12 */
> +	0xc6, /* 13 */
> +	0x11, /* 14 */
> +	0x5c, /* 15 */
> +	0xa9, /* 16 */
> +	0xe4, /* 17 */
> +	0x33, /* 18 */
> +	0x7e, /* 19 */
> +	0xd0, /* 20 */
> +	0x9d, /* 21 */
> +	0x4a, /* 22 */
> +	0x07, /* 23 */
> +	0x5b, /* 24 */
> +	0x16, /* 25 */
> +	0xc1, /* 26 */
> +	0x8c, /* 27 */
> +	0x22, /* 28 */
> +	0x6f, /* 29 */
> +	0xb8, /* 30 */
> +	0xf5, /* 31 */
> +	0x1f, /* 32 */
> +	0x52, /* 33 */
> +	0x85, /* 34 */
> +	0xc8, /* 35 */
> +	0x66, /* 36 */
> +	0x2b, /* 37 */
> +	0xfc, /* 38 */
> +	0xb1, /* 39 */
> +	0xed, /* 40 */
> +	0xa0, /* 41 */
> +	0x77, /* 42 */
> +	0x3a, /* 43 */
> +	0x94, /* 44 */
> +	0xd9, /* 45 */
> +	0x0e, /* 46 */
> +	0x43, /* 47 */
> +	0xb6, /* 48 */
> +	0xfb, /* 49 */
> +	0x2c, /* 50 */
> +	0x61, /* 51 */
> +	0xcf, /* 52 */
> +	0x82, /* 53 */
> +	0x55, /* 54 */
> +	0x18, /* 55 */
> +	0x44, /* 56 */
> +	0x09, /* 57 */
> +	0xde, /* 58 */
> +	0x93, /* 59 */
> +	0x3d, /* 60 */
> +	0x70, /* 61 */
> +	0xa7, /* 62 */
> +	0xea, /* 63 */
> +	0x3e, /* 64 */
> +	0x73, /* 65 */
> +	0xa4, /* 66 */
> +	0xe9, /* 67 */
> +	0x47, /* 68 */
> +	0x0a, /* 69 */
> +	0xdd, /* 70 */
> +	0x90, /* 71 */
> +	0xcc, /* 72 */
> +	0x81, /* 73 */
> +	0x56, /* 74 */
> +	0x1b, /* 75 */
> +	0xb5, /* 76 */
> +	0xf8, /* 77 */
> +	0x2f, /* 78 */
> +	0x62, /* 79 */
> +	0x97, /* 80 */
> +	0xda, /* 81 */
> +	0x0d, /* 82 */
> +	0x40, /* 83 */
> +	0xee, /* 84 */
> +	0xa3, /* 85 */
> +	0x74, /* 86 */
> +	0x39, /* 87 */
> +	0x65, /* 88 */
> +	0x28, /* 89 */
> +	0xff, /* 90 */
> +	0xb2, /* 91 */
> +	0x1c, /* 92 */
> +	0x51, /* 93 */
> +	0x86, /* 94 */
> +	0xcb, /* 95 */
> +	0x21, /* 96 */
> +	0x6c, /* 97 */
> +	0xbb, /* 98 */
> +	0xf6, /* 99 */
> +	0x58, /* 100 */
> +	0x15, /* 101 */
> +	0xc2, /* 102 */
> +	0x8f, /* 103 */
> +	0xd3, /* 104 */
> +	0x9e, /* 105 */
> +	0x49, /* 106 */
> +	0x04, /* 107 */
> +	0xaa, /* 108 */
> +	0xe7, /* 109 */
> +	0x30, /* 110 */
> +	0x7d, /* 111 */
> +	0x88, /* 112 */
> +	0xc5, /* 113 */
> +	0x12, /* 114 */
> +	0x5f, /* 115 */
> +	0xf1, /* 116 */
> +	0xbc, /* 117 */
> +	0x6b, /* 118 */
> +	0x26, /* 119 */
> +	0x7a, /* 120 */
> +	0x37, /* 121 */
> +	0xe0, /* 122 */
> +	0xad, /* 123 */
> +	0x03, /* 124 */
> +	0x4e, /* 125 */
> +	0x99, /* 126 */
> +	0xd4, /* 127 */
> +	0x7c, /* 128 */
> +	0x31, /* 129 */
> +	0xe6, /* 130 */
> +	0xab, /* 131 */
> +	0x05, /* 132 */
> +	0x48, /* 133 */
> +	0x9f, /* 134 */
> +	0xd2, /* 135 */
> +	0x8e, /* 136 */
> +	0xc3, /* 137 */
> +	0x14, /* 138 */
> +	0x59, /* 139 */
> +	0xf7, /* 140 */
> +	0xba, /* 141 */
> +	0x6d, /* 142 */
> +	0x20, /* 143 */
> +	0xd5, /* 144 */
> +	0x98, /* 145 */
> +	0x4f, /* 146 */
> +	0x02, /* 147 */
> +	0xac, /* 148 */
> +	0xe1, /* 149 */
> +	0x36, /* 150 */
> +	0x7b, /* 151 */
> +	0x27, /* 152 */
> +	0x6a, /* 153 */
> +	0xbd, /* 154 */
> +	0xf0, /* 155 */
> +	0x5e, /* 156 */
> +	0x13, /* 157 */
> +	0xc4, /* 158 */
> +	0x89, /* 159 */
> +	0x63, /* 160 */
> +	0x2e, /* 161 */
> +	0xf9, /* 162 */
> +	0xb4, /* 163 */
> +	0x1a, /* 164 */
> +	0x57, /* 165 */
> +	0x80, /* 166 */
> +	0xcd, /* 167 */
> +	0x91, /* 168 */
> +	0xdc, /* 169 */
> +	0x0b, /* 170 */
> +	0x46, /* 171 */
> +	0xe8, /* 172 */
> +	0xa5, /* 173 */
> +	0x72, /* 174 */
> +	0x3f, /* 175 */
> +	0xca, /* 176 */
> +	0x87, /* 177 */
> +	0x50, /* 178 */
> +	0x1d, /* 179 */
> +	0xb3, /* 180 */
> +	0xfe, /* 181 */
> +	0x29, /* 182 */
> +	0x64, /* 183 */
> +	0x38, /* 184 */
> +	0x75, /* 185 */
> +	0xa2, /* 186 */
> +	0xef, /* 187 */
> +	0x41, /* 188 */
> +	0x0c, /* 189 */
> +	0xdb, /* 190 */
> +	0x96, /* 191 */
> +	0x42, /* 192 */
> +	0x0f, /* 193 */
> +	0xd8, /* 194 */
> +	0x95, /* 195 */
> +	0x3b, /* 196 */
> +	0x76, /* 197 */
> +	0xa1, /* 198 */
> +	0xec, /* 199 */
> +	0xb0, /* 200 */
> +	0xfd, /* 201 */
> +	0x2a, /* 202 */
> +	0x67, /* 203 */
> +	0xc9, /* 204 */
> +	0x84, /* 205 */
> +	0x53, /* 206 */
> +	0x1e, /* 207 */
> +	0xeb, /* 208 */
> +	0xa6, /* 209 */
> +	0x71, /* 210 */
> +	0x3c, /* 211 */
> +	0x92, /* 212 */
> +	0xdf, /* 213 */
> +	0x08, /* 214 */
> +	0x45, /* 215 */
> +	0x19, /* 216 */
> +	0x54, /* 217 */
> +	0x83, /* 218 */
> +	0xce, /* 219 */
> +	0x60, /* 220 */
> +	0x2d, /* 221 */
> +	0xfa, /* 222 */
> +	0xb7, /* 223 */
> +	0x5d, /* 224 */
> +	0x10, /* 225 */
> +	0xc7, /* 226 */
> +	0x8a, /* 227 */
> +	0x24, /* 228 */
> +	0x69, /* 229 */
> +	0xbe, /* 230 */
> +	0xf3, /* 231 */
> +	0xaf, /* 232 */
> +	0xe2, /* 233 */
> +	0x35, /* 234 */
> +	0x78, /* 235 */
> +	0xd6, /* 236 */
> +	0x9b, /* 237 */
> +	0x4c, /* 238 */
> +	0x01, /* 239 */
> +	0xf4, /* 240 */
> +	0xb9, /* 241 */
> +	0x6e, /* 242 */
> +	0x23, /* 243 */
> +	0x8d, /* 244 */
> +	0xc0, /* 245 */
> +	0x17, /* 246 */
> +	0x5a, /* 247 */
> +	0x06, /* 248 */
> +	0x4b, /* 249 */
> +	0x9c, /* 250 */
> +	0xd1, /* 251 */
> +	0x7f, /* 252 */
> +	0x32, /* 253 */
> +	0xe5, /* 254 */
> +	0xa8  /* 255 */
> +};
> +EXPORT_SYMBOL(sdw_crc8_lookup_msb);
> diff --git a/drivers/soundwire/crc8.h b/drivers/soundwire/crc8.h
> new file mode 100644
> index 000000000000..9a88d3866016
> --- /dev/null
> +++ b/drivers/soundwire/crc8.h
> @@ -0,0 +1,11 @@
> +/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
> +/* Copyright(c) 2024 Intel Corporation. */
> +
> +#ifndef __SDW_CRC8_H
> +#define __SDW_CRC8_H
> +
> +#define SDW_CRC8_SEED 0xFF
> +#define SDW_CRC8_POLY 0x4D
> +extern const u8 sdw_crc8_lookup_msb[CRC8_TABLE_SIZE];
> +
> +#endif /* __SDW_CRC8_H */
> -- 
> 2.39.2
>
Pierre-Louis Bossart Dec. 18, 2023, 1:26 p.m. UTC | #2 
On 12/18/23 06:01, Vinod Koul wrote:
> On 07-12-23, 16:29, Pierre-Louis Bossart wrote:
>> Add the lookup table required by crc8(). All configuration values were
>> directly table from the MIPI SoundWire 1.x specification.
>>
>> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
>> ---
>>  drivers/soundwire/Makefile |   4 +-
>>  drivers/soundwire/crc8.c   | 277 +++++++++++++++++++++++++++++++++++++
>>  drivers/soundwire/crc8.h   |  11 ++
>>  3 files changed, 291 insertions(+), 1 deletion(-)
>>  create mode 100644 drivers/soundwire/crc8.c
>>  create mode 100644 drivers/soundwire/crc8.h
>>
>> diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile
>> index 657f5888a77b..170128dd9318 100644
>> --- a/drivers/soundwire/Makefile
>> +++ b/drivers/soundwire/Makefile
>> @@ -5,7 +5,9 @@
>>  
>>  #Bus Objs
>>  soundwire-bus-y := bus_type.o bus.o master.o slave.o mipi_disco.o stream.o  \
>> -			sysfs_slave.o sysfs_slave_dpn.o
>> +			sysfs_slave.o sysfs_slave_dpn.o \
>> +			crc8.o
>> +
>>  obj-$(CONFIG_SOUNDWIRE) += soundwire-bus.o
>>  
>>  soundwire-generic-allocation-objs := generic_bandwidth_allocation.o
>> diff --git a/drivers/soundwire/crc8.c b/drivers/soundwire/crc8.c
>> new file mode 100644
>> index 000000000000..b6b984d7f39a
>> --- /dev/null
>> +++ b/drivers/soundwire/crc8.c
>> @@ -0,0 +1,277 @@
>> +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
>> +// Copyright(c) 2024 Intel Corporation.
>> +
>> +#include <linux/crc8.h>
>> +#include <linux/module.h>
>> +#include "crc8.h"
>> +
>> +/*
>> + * the MIPI SoundWire CRC8 polynomial is X^8 + X^6 + X^3 + X^2 + 1, MSB first
>> + * The value is (1)01001101 = 0x4D
>> + *
>> + * the table below was generated with
>> + *
>> + *	u8 crc8_lookup_table[CRC8_TABLE_SIZE];
>> + *	crc8_populate_msb(crc8_lookup_table, SDW_CRC8_POLY);
> 
> Good that you found this API, so next question would be why should we
> have this static table in kernel and not generate on probe if bpt is
> supported..? Many subsystems use these APIs to generate the tables..

The table is going to be the same for all hosts, it's simpler if
everyone uses a constant table, no? We're talking about 256 bytes added
for the common bus parts, be it with dynamically allocated memory or a
static table.

I don't mind reverting to a dynamically allocated table populated at
boot if that was the consensus.
Vinod Koul Dec. 21, 2023, 2:42 p.m. UTC | #3 
On 18-12-23, 14:26, Pierre-Louis Bossart wrote:
> 
> 
> On 12/18/23 06:01, Vinod Koul wrote:
> > On 07-12-23, 16:29, Pierre-Louis Bossart wrote:
> >> Add the lookup table required by crc8(). All configuration values were
> >> directly table from the MIPI SoundWire 1.x specification.
> >>
> >> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
> >> ---
> >>  drivers/soundwire/Makefile |   4 +-
> >>  drivers/soundwire/crc8.c   | 277 +++++++++++++++++++++++++++++++++++++
> >>  drivers/soundwire/crc8.h   |  11 ++
> >>  3 files changed, 291 insertions(+), 1 deletion(-)
> >>  create mode 100644 drivers/soundwire/crc8.c
> >>  create mode 100644 drivers/soundwire/crc8.h
> >>
> >> diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile
> >> index 657f5888a77b..170128dd9318 100644
> >> --- a/drivers/soundwire/Makefile
> >> +++ b/drivers/soundwire/Makefile
> >> @@ -5,7 +5,9 @@
> >>  
> >>  #Bus Objs
> >>  soundwire-bus-y := bus_type.o bus.o master.o slave.o mipi_disco.o stream.o  \
> >> -			sysfs_slave.o sysfs_slave_dpn.o
> >> +			sysfs_slave.o sysfs_slave_dpn.o \
> >> +			crc8.o
> >> +
> >>  obj-$(CONFIG_SOUNDWIRE) += soundwire-bus.o
> >>  
> >>  soundwire-generic-allocation-objs := generic_bandwidth_allocation.o
> >> diff --git a/drivers/soundwire/crc8.c b/drivers/soundwire/crc8.c
> >> new file mode 100644
> >> index 000000000000..b6b984d7f39a
> >> --- /dev/null
> >> +++ b/drivers/soundwire/crc8.c
> >> @@ -0,0 +1,277 @@
> >> +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
> >> +// Copyright(c) 2024 Intel Corporation.
> >> +
> >> +#include <linux/crc8.h>
> >> +#include <linux/module.h>
> >> +#include "crc8.h"
> >> +
> >> +/*
> >> + * the MIPI SoundWire CRC8 polynomial is X^8 + X^6 + X^3 + X^2 + 1, MSB first
> >> + * The value is (1)01001101 = 0x4D
> >> + *
> >> + * the table below was generated with
> >> + *
> >> + *	u8 crc8_lookup_table[CRC8_TABLE_SIZE];
> >> + *	crc8_populate_msb(crc8_lookup_table, SDW_CRC8_POLY);
> > 
> > Good that you found this API, so next question would be why should we
> > have this static table in kernel and not generate on probe if bpt is
> > supported..? Many subsystems use these APIs to generate the tables..
> 
> The table is going to be the same for all hosts, it's simpler if
> everyone uses a constant table, no? We're talking about 256 bytes added
> for the common bus parts, be it with dynamically allocated memory or a
> static table.
> 
> I don't mind reverting to a dynamically allocated table populated at
> boot if that was the consensus.

Most of the kernel users I looked have dynamically allocated table
populated at boot, also out of many users how many would support BTP.?
Your older platforms, current qcom dont, so not point is adding for
everyone...
Pierre-Louis Bossart Dec. 21, 2023, 5:15 p.m. UTC | #4 
On 12/21/23 15:42, Vinod Koul wrote:
> On 18-12-23, 14:26, Pierre-Louis Bossart wrote:
>>
>>
>> On 12/18/23 06:01, Vinod Koul wrote:
>>> On 07-12-23, 16:29, Pierre-Louis Bossart wrote:
>>>> Add the lookup table required by crc8(). All configuration values were
>>>> directly table from the MIPI SoundWire 1.x specification.
>>>>
>>>> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
>>>> ---
>>>>  drivers/soundwire/Makefile |   4 +-
>>>>  drivers/soundwire/crc8.c   | 277 +++++++++++++++++++++++++++++++++++++
>>>>  drivers/soundwire/crc8.h   |  11 ++
>>>>  3 files changed, 291 insertions(+), 1 deletion(-)
>>>>  create mode 100644 drivers/soundwire/crc8.c
>>>>  create mode 100644 drivers/soundwire/crc8.h
>>>>
>>>> diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile
>>>> index 657f5888a77b..170128dd9318 100644
>>>> --- a/drivers/soundwire/Makefile
>>>> +++ b/drivers/soundwire/Makefile
>>>> @@ -5,7 +5,9 @@
>>>>  
>>>>  #Bus Objs
>>>>  soundwire-bus-y := bus_type.o bus.o master.o slave.o mipi_disco.o stream.o  \
>>>> -			sysfs_slave.o sysfs_slave_dpn.o
>>>> +			sysfs_slave.o sysfs_slave_dpn.o \
>>>> +			crc8.o
>>>> +
>>>>  obj-$(CONFIG_SOUNDWIRE) += soundwire-bus.o
>>>>  
>>>>  soundwire-generic-allocation-objs := generic_bandwidth_allocation.o
>>>> diff --git a/drivers/soundwire/crc8.c b/drivers/soundwire/crc8.c
>>>> new file mode 100644
>>>> index 000000000000..b6b984d7f39a
>>>> --- /dev/null
>>>> +++ b/drivers/soundwire/crc8.c
>>>> @@ -0,0 +1,277 @@
>>>> +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
>>>> +// Copyright(c) 2024 Intel Corporation.
>>>> +
>>>> +#include <linux/crc8.h>
>>>> +#include <linux/module.h>
>>>> +#include "crc8.h"
>>>> +
>>>> +/*
>>>> + * the MIPI SoundWire CRC8 polynomial is X^8 + X^6 + X^3 + X^2 + 1, MSB first
>>>> + * The value is (1)01001101 = 0x4D
>>>> + *
>>>> + * the table below was generated with
>>>> + *
>>>> + *	u8 crc8_lookup_table[CRC8_TABLE_SIZE];
>>>> + *	crc8_populate_msb(crc8_lookup_table, SDW_CRC8_POLY);
>>>
>>> Good that you found this API, so next question would be why should we
>>> have this static table in kernel and not generate on probe if bpt is
>>> supported..? Many subsystems use these APIs to generate the tables..
>>
>> The table is going to be the same for all hosts, it's simpler if
>> everyone uses a constant table, no? We're talking about 256 bytes added
>> for the common bus parts, be it with dynamically allocated memory or a
>> static table.
>>
>> I don't mind reverting to a dynamically allocated table populated at
>> boot if that was the consensus.
> 
> Most of the kernel users I looked have dynamically allocated table
> populated at boot, also out of many users how many would support BTP.?
> Your older platforms, current qcom dont, so not point is adding for
> everyone...

All Intel hardware supports BTP/BRA, we just didn't have a compelling
reason to enable it so far. I've seen AMD stating that they also have
BTP/BRA. That's 2/3 of controllers.

I don't mind reverting to a devm_ allocated table, I am not sure I see
the benefits for 256 bytes of constant data.
Vinod Koul Dec. 21, 2023, 5:21 p.m. UTC | #5 
On 21-12-23, 18:15, Pierre-Louis Bossart wrote:

> >> I don't mind reverting to a dynamically allocated table populated at
> >> boot if that was the consensus.
> > 
> > Most of the kernel users I looked have dynamically allocated table
> > populated at boot, also out of many users how many would support BTP.?
> > Your older platforms, current qcom dont, so not point is adding for
> > everyone...
> 
> All Intel hardware supports BTP/BRA, we just didn't have a compelling
> reason to enable it so far. I've seen AMD stating that they also have
> BTP/BRA. That's 2/3 of controllers.

Not all qcom platforms support this, so this would be enabled
selectively for them
diff mbox series

Patch

diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile
index 657f5888a77b..170128dd9318 100644
--- a/drivers/soundwire/Makefile
+++ b/drivers/soundwire/Makefile
@@ -5,7 +5,9 @@ 
 
 #Bus Objs
 soundwire-bus-y := bus_type.o bus.o master.o slave.o mipi_disco.o stream.o  \
-			sysfs_slave.o sysfs_slave_dpn.o
+			sysfs_slave.o sysfs_slave_dpn.o \
+			crc8.o
+
 obj-$(CONFIG_SOUNDWIRE) += soundwire-bus.o
 
 soundwire-generic-allocation-objs := generic_bandwidth_allocation.o
diff --git a/drivers/soundwire/crc8.c b/drivers/soundwire/crc8.c
new file mode 100644
index 000000000000..b6b984d7f39a
--- /dev/null
+++ b/drivers/soundwire/crc8.c
@@ -0,0 +1,277 @@ 
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2024 Intel Corporation.
+
+#include <linux/crc8.h>
+#include <linux/module.h>
+#include "crc8.h"
+
+/*
+ * the MIPI SoundWire CRC8 polynomial is X^8 + X^6 + X^3 + X^2 + 1, MSB first
+ * The value is (1)01001101 = 0x4D
+ *
+ * the table below was generated with
+ *
+ *	u8 crc8_lookup_table[CRC8_TABLE_SIZE];
+ *	crc8_populate_msb(crc8_lookup_table, SDW_CRC8_POLY);
+ *
+ */
+
+const u8 sdw_crc8_lookup_msb[CRC8_TABLE_SIZE] = {
+	0x00, /* 0 */
+	0x4d, /* 1 */
+	0x9a, /* 2 */
+	0xd7, /* 3 */
+	0x79, /* 4 */
+	0x34, /* 5 */
+	0xe3, /* 6 */
+	0xae, /* 7 */
+	0xf2, /* 8 */
+	0xbf, /* 9 */
+	0x68, /* 10 */
+	0x25, /* 11 */
+	0x8b, /* 12 */
+	0xc6, /* 13 */
+	0x11, /* 14 */
+	0x5c, /* 15 */
+	0xa9, /* 16 */
+	0xe4, /* 17 */
+	0x33, /* 18 */
+	0x7e, /* 19 */
+	0xd0, /* 20 */
+	0x9d, /* 21 */
+	0x4a, /* 22 */
+	0x07, /* 23 */
+	0x5b, /* 24 */
+	0x16, /* 25 */
+	0xc1, /* 26 */
+	0x8c, /* 27 */
+	0x22, /* 28 */
+	0x6f, /* 29 */
+	0xb8, /* 30 */
+	0xf5, /* 31 */
+	0x1f, /* 32 */
+	0x52, /* 33 */
+	0x85, /* 34 */
+	0xc8, /* 35 */
+	0x66, /* 36 */
+	0x2b, /* 37 */
+	0xfc, /* 38 */
+	0xb1, /* 39 */
+	0xed, /* 40 */
+	0xa0, /* 41 */
+	0x77, /* 42 */
+	0x3a, /* 43 */
+	0x94, /* 44 */
+	0xd9, /* 45 */
+	0x0e, /* 46 */
+	0x43, /* 47 */
+	0xb6, /* 48 */
+	0xfb, /* 49 */
+	0x2c, /* 50 */
+	0x61, /* 51 */
+	0xcf, /* 52 */
+	0x82, /* 53 */
+	0x55, /* 54 */
+	0x18, /* 55 */
+	0x44, /* 56 */
+	0x09, /* 57 */
+	0xde, /* 58 */
+	0x93, /* 59 */
+	0x3d, /* 60 */
+	0x70, /* 61 */
+	0xa7, /* 62 */
+	0xea, /* 63 */
+	0x3e, /* 64 */
+	0x73, /* 65 */
+	0xa4, /* 66 */
+	0xe9, /* 67 */
+	0x47, /* 68 */
+	0x0a, /* 69 */
+	0xdd, /* 70 */
+	0x90, /* 71 */
+	0xcc, /* 72 */
+	0x81, /* 73 */
+	0x56, /* 74 */
+	0x1b, /* 75 */
+	0xb5, /* 76 */
+	0xf8, /* 77 */
+	0x2f, /* 78 */
+	0x62, /* 79 */
+	0x97, /* 80 */
+	0xda, /* 81 */
+	0x0d, /* 82 */
+	0x40, /* 83 */
+	0xee, /* 84 */
+	0xa3, /* 85 */
+	0x74, /* 86 */
+	0x39, /* 87 */
+	0x65, /* 88 */
+	0x28, /* 89 */
+	0xff, /* 90 */
+	0xb2, /* 91 */
+	0x1c, /* 92 */
+	0x51, /* 93 */
+	0x86, /* 94 */
+	0xcb, /* 95 */
+	0x21, /* 96 */
+	0x6c, /* 97 */
+	0xbb, /* 98 */
+	0xf6, /* 99 */
+	0x58, /* 100 */
+	0x15, /* 101 */
+	0xc2, /* 102 */
+	0x8f, /* 103 */
+	0xd3, /* 104 */
+	0x9e, /* 105 */
+	0x49, /* 106 */
+	0x04, /* 107 */
+	0xaa, /* 108 */
+	0xe7, /* 109 */
+	0x30, /* 110 */
+	0x7d, /* 111 */
+	0x88, /* 112 */
+	0xc5, /* 113 */
+	0x12, /* 114 */
+	0x5f, /* 115 */
+	0xf1, /* 116 */
+	0xbc, /* 117 */
+	0x6b, /* 118 */
+	0x26, /* 119 */
+	0x7a, /* 120 */
+	0x37, /* 121 */
+	0xe0, /* 122 */
+	0xad, /* 123 */
+	0x03, /* 124 */
+	0x4e, /* 125 */
+	0x99, /* 126 */
+	0xd4, /* 127 */
+	0x7c, /* 128 */
+	0x31, /* 129 */
+	0xe6, /* 130 */
+	0xab, /* 131 */
+	0x05, /* 132 */
+	0x48, /* 133 */
+	0x9f, /* 134 */
+	0xd2, /* 135 */
+	0x8e, /* 136 */
+	0xc3, /* 137 */
+	0x14, /* 138 */
+	0x59, /* 139 */
+	0xf7, /* 140 */
+	0xba, /* 141 */
+	0x6d, /* 142 */
+	0x20, /* 143 */
+	0xd5, /* 144 */
+	0x98, /* 145 */
+	0x4f, /* 146 */
+	0x02, /* 147 */
+	0xac, /* 148 */
+	0xe1, /* 149 */
+	0x36, /* 150 */
+	0x7b, /* 151 */
+	0x27, /* 152 */
+	0x6a, /* 153 */
+	0xbd, /* 154 */
+	0xf0, /* 155 */
+	0x5e, /* 156 */
+	0x13, /* 157 */
+	0xc4, /* 158 */
+	0x89, /* 159 */
+	0x63, /* 160 */
+	0x2e, /* 161 */
+	0xf9, /* 162 */
+	0xb4, /* 163 */
+	0x1a, /* 164 */
+	0x57, /* 165 */
+	0x80, /* 166 */
+	0xcd, /* 167 */
+	0x91, /* 168 */
+	0xdc, /* 169 */
+	0x0b, /* 170 */
+	0x46, /* 171 */
+	0xe8, /* 172 */
+	0xa5, /* 173 */
+	0x72, /* 174 */
+	0x3f, /* 175 */
+	0xca, /* 176 */
+	0x87, /* 177 */
+	0x50, /* 178 */
+	0x1d, /* 179 */
+	0xb3, /* 180 */
+	0xfe, /* 181 */
+	0x29, /* 182 */
+	0x64, /* 183 */
+	0x38, /* 184 */
+	0x75, /* 185 */
+	0xa2, /* 186 */
+	0xef, /* 187 */
+	0x41, /* 188 */
+	0x0c, /* 189 */
+	0xdb, /* 190 */
+	0x96, /* 191 */
+	0x42, /* 192 */
+	0x0f, /* 193 */
+	0xd8, /* 194 */
+	0x95, /* 195 */
+	0x3b, /* 196 */
+	0x76, /* 197 */
+	0xa1, /* 198 */
+	0xec, /* 199 */
+	0xb0, /* 200 */
+	0xfd, /* 201 */
+	0x2a, /* 202 */
+	0x67, /* 203 */
+	0xc9, /* 204 */
+	0x84, /* 205 */
+	0x53, /* 206 */
+	0x1e, /* 207 */
+	0xeb, /* 208 */
+	0xa6, /* 209 */
+	0x71, /* 210 */
+	0x3c, /* 211 */
+	0x92, /* 212 */
+	0xdf, /* 213 */
+	0x08, /* 214 */
+	0x45, /* 215 */
+	0x19, /* 216 */
+	0x54, /* 217 */
+	0x83, /* 218 */
+	0xce, /* 219 */
+	0x60, /* 220 */
+	0x2d, /* 221 */
+	0xfa, /* 222 */
+	0xb7, /* 223 */
+	0x5d, /* 224 */
+	0x10, /* 225 */
+	0xc7, /* 226 */
+	0x8a, /* 227 */
+	0x24, /* 228 */
+	0x69, /* 229 */
+	0xbe, /* 230 */
+	0xf3, /* 231 */
+	0xaf, /* 232 */
+	0xe2, /* 233 */
+	0x35, /* 234 */
+	0x78, /* 235 */
+	0xd6, /* 236 */
+	0x9b, /* 237 */
+	0x4c, /* 238 */
+	0x01, /* 239 */
+	0xf4, /* 240 */
+	0xb9, /* 241 */
+	0x6e, /* 242 */
+	0x23, /* 243 */
+	0x8d, /* 244 */
+	0xc0, /* 245 */
+	0x17, /* 246 */
+	0x5a, /* 247 */
+	0x06, /* 248 */
+	0x4b, /* 249 */
+	0x9c, /* 250 */
+	0xd1, /* 251 */
+	0x7f, /* 252 */
+	0x32, /* 253 */
+	0xe5, /* 254 */
+	0xa8  /* 255 */
+};
+EXPORT_SYMBOL(sdw_crc8_lookup_msb);
diff --git a/drivers/soundwire/crc8.h b/drivers/soundwire/crc8.h
new file mode 100644
index 000000000000..9a88d3866016
--- /dev/null
+++ b/drivers/soundwire/crc8.h
@@ -0,0 +1,11 @@ 
+/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
+/* Copyright(c) 2024 Intel Corporation. */
+
+#ifndef __SDW_CRC8_H
+#define __SDW_CRC8_H
+
+#define SDW_CRC8_SEED 0xFF
+#define SDW_CRC8_POLY 0x4D
+extern const u8 sdw_crc8_lookup_msb[CRC8_TABLE_SIZE];
+
+#endif /* __SDW_CRC8_H */