I/O Resource Management
[Linux DDE Common]

This module emulates the I/O resource management inside the Linux kernel. More...

Functions
resource *	request_region (unsigned long start, unsigned long n, const char *name)
	Allocate I/O port region.
resource *	request_mem_region (unsigned long start, unsigned long n, const char *name)
	Allocate I/O memory region.
void	release_region (unsigned long start, unsigned long n)
	Release I/O port region.
void	release_mem_region (unsigned long start, unsigned long n)
	Release I/O memory region.
int	release_resource (struct resource *res)
	Release any resource.
int	check_region (unsigned long start, unsigned long n)
	Check I/O port region availability.
int	check_mem_region (unsigned long start, unsigned long n)
	Check I/O memory region availability.
void *	ioremap (unsigned long phys_addr, unsigned long size)
	Remap I/O memory into kernel address space.
void *	ioremap_nocache (unsigned long phys_addr, unsigned long size)
	Remap I/O memory into kernel address space (no cache).
void	iounmap (void *addr)
	Unmap I/O memory from kernel address space.

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Detailed Description

This module emulates the I/O resource management inside the Linux kernel.

It is mostly a wrapper to libio request/release functions for I/O port and memory regions with additional bookkeeping of allocations. The ioremap()/iounmap() interface is also provided by this module.

Requirements: (additionally to Global Requirements)

• initialized libio

Todo:

I/O memory as dataspaces?!

region handling

1. put regions in conversion list via address_add_region() too
2. hold only 1 region list (address.c) and call address_*() and _va()

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Function Documentation

int check_mem_region (  unsigned long  start, unsigned long  n )

Check I/O memory region availability. Parameters: start  begin of region n  length of region Returns: always 0 NO support for this. Definition at line 198 of file res.c.

int check_region (  unsigned long  start, unsigned long  n )

Check I/O port region availability. Parameters: start  begin of region n  length of region Returns: always 0 NO support for this. Definition at line 183 of file res.c.

void* ioremap (  unsigned long  phys_addr, unsigned long  size )

Remap I/O memory into kernel address space. Parameters: phys_addr  begin of physical address range size  size of physical address range Returns: virtual start address of mapped range Here no real mapping is done. Only the virtual address is returned. Definition at line 213 of file res.c. References __va(), DEBUG_RES, DEBUG_RES_TRACE, and regions. Referenced by ioremap_nocache().

void* ioremap_nocache (  unsigned long  phys_addr, unsigned long  size )

Remap I/O memory into kernel address space (no cache). Parameters: phys_addr  begin of physical address range size  size of physical address range Returns: virtual start address of mapped range Here no real mapping is done. Only the virtual address is returned (by calling ioremap()). Definition at line 259 of file res.c. References DEBUG_RES_TRACE, and ioremap().

void iounmap (  void *  addr  )

Unmap I/O memory from kernel address space. Parameters: addr  virtual start address Do nothing. Definition at line 273 of file res.c. References DEBUG_RES_TRACE.

void release_mem_region (  unsigned long  start, unsigned long  n )

Release I/O memory region. Parameters: start  begin of region n  length of region Definition at line 141 of file res.c. References dde_remove_region(), DEBUG_ERRORS, DEBUG_RES_TRACE, and regions. Referenced by pci_release_region().

void release_region (  unsigned long  start, unsigned long  n )

Release I/O port region. Parameters: start  begin of region n  length of region Definition at line 124 of file res.c. References DEBUG_RES_TRACE. Referenced by pci_release_region().

int release_resource (  struct resource *  res  )

Release any resource. Parameters: resource  the resource to free Todo: implementation Definition at line 166 of file res.c.

struct resource* request_mem_region (  unsigned long  start, unsigned long  n, const char *  name )

Allocate I/O memory region. Parameters: start  begin of region n  length of region name  name of requester Test: krishna: hopefully nobody uses return values Bug: Return value is a bogus pointer. Definition at line 97 of file res.c. References dde_add_region(), DEBUG_ERRORS, DEBUG_RES_TRACE, and regions. Referenced by pci_request_region().

struct resource* request_region (  unsigned long  start, unsigned long  n, const char *  name )

Allocate I/O port region. Parameters: start  begin of region n  length of region name  name of requester Test: krishna: hopefully nobody uses return values Bug: Return value is a bogus pointer. Definition at line 70 of file res.c. References DEBUG_ERRORS, and DEBUG_RES_TRACE. Referenced by pci_request_region().

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