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/****************************************************************************
* include/nuttx/pgalloc.h
* Page memory allocator.
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_PGALLOC_H
#define __INCLUDE_NUTTX_PGALLOC_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#ifdef CONFIG_MM_PGALLOC
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* CONFIG_MM_PGALLOC - Enable page allocator support
* CONFIG_MM_PGSIZE - The page size. Must be one of {1024, 2048,
* 4096, 8192, or 16384}. This is easily extensible, but only those
* values are currently support.
* CONFIG_DEBUG_PGALLOC - Just like CONFIG_DEBUG_MM, but only generates
* output from the page allocation logic.
*
* Dependencies: CONFIG_ARCH_USE_MMU and CONFIG_GRAN
*/
#ifndef CONFIG_MM_PGALLOC_PGSIZE
# define CONFIG_MM_PGALLOC_PGSIZE 4096
#endif
#if CONFIG_MM_PGSIZE == 1024
# define MM_PGSIZE 1024
# define MM_PGSHIFT 10
#elif CONFIG_MM_PGSIZE == 2048
# define MM_PGSIZE 2048
# define MM_PGSHIFT 11
#elif CONFIG_MM_PGSIZE == 4096
# define MM_PGSIZE 4096
# define MM_PGSHIFT 12
#elif CONFIG_MM_PGSIZE == 8192
# define MM_PGSIZE 8192
# define MM_PGSHIFT 13
#elif CONFIG_MM_PGSIZE == 16384
# define MM_PGSIZE 16384
# define MM_PGSHIFT 14
#else
# error CONFIG_MM_PGSIZE not supported
#endif
#define MM_PGMASK (MM_PGSIZE - 1)
#define MM_PGALIGNDOWN(a) ((uintptr_t)(a) & ~MM_PGMASK)
#define MM_PGALIGNUP(a) (((uintptr_t)(a) + MM_PGMASK) & ~MM_PGMASK)
#define MM_NPAGES(s) (((uintptr_t)(s) + MM_PGMASK) >> MM_PGSHIFT)
#define MM_ISALIGNED(a) (((uintptr_t)(a) & MM_PGMASK) == 0)
/****************************************************************************
* Public Types
****************************************************************************/
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Name: mm_pginitialize
*
* Description:
* Initialize the page allocator.
*
* Input Parameters:
* heap_start - The physical address of the start of memory region that
* will be used for the page allocator heap
* heap_size - The size (in bytes) of the memory region that will be used
* for the page allocator heap.
*
* Returned Value:
* None
*
****************************************************************************/
void mm_pginitialize(FAR void *heap_start, size_t heap_size);
/****************************************************************************
* Name: mm_pgreserve
*
* Description:
* Reserve memory in the page memory pool. This will reserve the pages
* that contain the start and end addresses plus all of the pages
* in between. This should be done early in the initialization sequence
* before any other allocations are made.
*
* Reserved memory can never be allocated (it can be freed however which
* essentially unreserves the memory).
*
* Input Parameters:
* start - The address of the beginning of the region to be reserved.
* size - The size of the region to be reserved
*
* Returned Value:
* None
*
****************************************************************************/
void mm_pgreserve(uintptr_t start, size_t size);
/****************************************************************************
* Name: mm_pgalloc
*
* Description:
* Allocate page memory from the page memory pool.
*
* Input Parameters:
* npages - The number of pages to allocate, each of size CONFIG_MM_PGSIZE.
*
* Returned Value:
* On success, a non-zero, physical address of the allocated page memory
* is returned. Zero is returned on failure. NOTE: This is an unmapped
* physical address and cannot be used until it is appropriately mapped.
*
****************************************************************************/
uintptr_t mm_pgalloc(unsigned int npages);
/****************************************************************************
* Name: mm_pgfree
*
* Description:
* Return page memory to the page memory pool.
*
* Input Parameters:
* paddr - A physical address to a page in the page memory pool previously
* allocated by mm_pgalloc.
* npages - The number of contiguous pages to be return to the page memory
* pool, beginning with the page at paddr;
*
* Returned Value:
* None
*
****************************************************************************/
void mm_pgfree(uintptr_t paddr, unsigned int npages);
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* CONFIG_MM_PGALLOC */
#endif /* __INCLUDE_NUTTX_PGALLOC_H */
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