Generic bitfield packing and unpacking
modulename: packing.ko
configname: CONFIG_PACKING
Linux Kernel Configuration
└─>Library routines
└─>Generic bitfield packing and unpacking
In linux kernel since version 4.14.326 (release Date: 2023-09-23)
This option provides the packing() helper function, which permits
converting bitfields between a CPU-usable representation and a
memory representation that can have any combination of these quirks:
- Is little endian (bytes are reversed within a 32-bit group)
- The least-significant 32-bit word comes first (within a 64-bit
group)
- The most significant bit of a byte is at its right (bit 0 of a
register description is numerically 2^7).
Drivers may use these helpers to match the bit indices as described
in the data sheets of the peripherals they are in control of.
When in doubt, say N.
converting bitfields between a CPU-usable representation and a
memory representation that can have any combination of these quirks:
- Is little endian (bytes are reversed within a 32-bit group)
- The least-significant 32-bit word comes first (within a 64-bit
group)
- The most significant bit of a byte is at its right (bit 0 of a
register description is numerically 2^7).
Drivers may use these helpers to match the bit indices as described
in the data sheets of the peripherals they are in control of.
When in doubt, say N.