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/**
* @file
*
* @ingroup RTEMSScoreAddress
*
* @brief Information Required to Manipulate Physical Addresses
*
* This include file contains the information required to manipulate
* physical addresses.
*/
/*
* COPYRIGHT (c) 1989-2006.
* On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#ifndef _RTEMS_SCORE_ADDRESS_H
#define _RTEMS_SCORE_ADDRESS_H
#include <rtems/score/cpu.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @defgroup RTEMSScoreAddress Address Handler
*
* @ingroup RTEMSScore
*
* @brief Support for Address Manipulation
*
* This handler encapsulates functionality which abstracts address
* manipulation in a portable manner.
*
* @{
*/
/**
* @brief Adds offset to an address.
*
* This function is used to add an @a offset to a @a base address.
* It returns the resulting address. This address is typically
* converted to an access type before being used further.
*
* @param base The base address to add the offset to.
* @param offset The offset to add to @a base.
*
* @return This method returns the resulting address.
*/
RTEMS_INLINE_ROUTINE void *_Addresses_Add_offset (
const void *base,
uintptr_t offset
)
{
return (void *)((uintptr_t)base + offset);
}
/**
* @brief Subtracts offset from an address.
*
* This function is used to subtract an @a offset from a @a base
* address. It returns the resulting address. This address is
* typically converted to an access type before being used further.
*
* @param base The base address to subtract the offset from.
* @param offset The offset to subtract from @a base.
*
* @return This method returns the resulting address.
*/
RTEMS_INLINE_ROUTINE void *_Addresses_Subtract_offset (
const void *base,
uintptr_t offset
)
{
return (void *)((uintptr_t)base - offset);
}
/**
* @brief Subtracts two addresses.
*
* This function is used to subtract two addresses. It returns the
* resulting offset.
*
* @param left The address on the left hand side of the subtraction.
* @param right The address on the right hand side of the subtraction.
*
* @return This method returns the resulting address.
*/
RTEMS_INLINE_ROUTINE intptr_t _Addresses_Subtract(
const void *left,
const void *right
)
{
return (intptr_t) ( (const char *) left - (const char *) right );
}
/**
* @brief Checks if address is aligned.
*
* This function returns true if the given address is correctly
* aligned for this processor and false otherwise. Proper alignment
* is based on correctness and efficiency.
*
* @param address The address being checked for alignment.
*
* @retval true The @a address is aligned.
* @retval false The @a address is not aligned.
*/
RTEMS_INLINE_ROUTINE bool _Addresses_Is_aligned(
const void *address
)
{
return ( (uintptr_t) address % CPU_ALIGNMENT ) == 0;
}
/**
* @brief Checks if address is in range.
*
* This function returns true if the given address is within the
* memory range specified and false otherwise. @a base is the address
* of the first byte in the memory range and @a limit is the address
* of the last byte in the memory range. The base address is
* assumed to be lower than the limit address.
*
* @param address The address to check if it is in the given range.
* @param base The lowest address of the range to check against.
* @param limit The highest address of the range to check against.
*
* @retval true The @a address is within the memory range specified
* @retval false The @a address is not within the memory range specified.
*/
RTEMS_INLINE_ROUTINE bool _Addresses_Is_in_range (
const void *address,
const void *base,
const void *limit
)
{
return (address >= base && address <= limit);
}
/**
* @brief Aligns address to nearest multiple of alignment, rounding up.
*
* This function returns the given address aligned to the given alignment.
* If the address already is aligned, or if alignment is 0, the address is
* returned as is. The returned address is greater than or equal to the
* given address.
*
* @param address The address to align to the given alignment.
* @param alignment The desired alignment for the address. It must be a power of two.
*
* @return Returns the aligned address.
*/
RTEMS_INLINE_ROUTINE void *_Addresses_Align_up(
void *address,
size_t alignment
)
{
uintptr_t mask = alignment - (uintptr_t)1;
return (void*)(((uintptr_t)address + mask) & ~mask);
}
/**
* @brief Aligns address to nearest multiple of alignment, truncating.
*
* This function returns the given address aligned to the given alignment.
* If the address already is aligned, or if alignment is 0, the address is
* returned as is. The returned address is less than or equal to the
* given address.
*
* @param address The address to align to the given alignment.
* @param alignment The desired alignment for the address. It must be a power of two.
*
* @return Returns the aligned address.
*/
RTEMS_INLINE_ROUTINE void *_Addresses_Align_down(
void *address,
size_t alignment
)
{
uintptr_t mask = alignment - (uintptr_t)1;
return (void*)((uintptr_t)address & ~mask);
}
/** @} */
#ifdef __cplusplus
}
#endif
#endif
/* end of include file */
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