I/O-port session interface
An I/O port session permits access to a range of ports. Inside this range
variable-sized accesses (i.e., 8, 16, 32 bit) at arbitrary addresses are
allowed - currently, alignment is not enforced. Core enforces that access is
limited to the session-defined range while the user provides physical I/O port
addresses as function parameters.
The design is founded on experiences while programming PCI configuration
space which needs two 32-bit port registers. Each byte, word and dword in
the data register must be explicitly accessible for read and write. The old
design needs six capabilities only for the data register.
Class Genode::Io_port_session
Public functions
inb
Read byte (8 bit)
| short |
address |
Physical i/o port address |
- Return
-
unsigned char Value read from port
inl
Read double word (32 bit)
| short |
address |
Physical i/o port address |
- Return
-
unsigned Value read from port
inw
Read word (16 bit)
| short |
address |
Physical i/o port address |
- Return
-
unsigned short Value read from port
outb
Write byte (8 bit)
| short |
address |
Physical i/o port address |
| char |
value |
Value to write to port |
outl
Write double word (32 bit)
| short |
address |
Physical i/o port address |
outw
Write word (16 bit)
| short |
address |
Physical i/o port address |
| short |
value |
Value to write to port |
service_name
