f331936969
Introduce a new board function alloc_chunk() to allocate dynamic memory. This allows the board code to implement memory allocations without using the standard malloc() interface. Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
55 lines
1.4 KiB
C
55 lines
1.4 KiB
C
// AVR miscellaneous platform code
|
|
//
|
|
// Copyright (C) 2016,2017 Kevin O'Connor <kevin@koconnor.net>
|
|
//
|
|
// This file may be distributed under the terms of the GNU GPLv3 license.
|
|
|
|
#include <avr/io.h> // AVR_STACK_POINTER_REG
|
|
#include <stdlib.h> // __malloc_heap_end
|
|
#include <string.h> // memset
|
|
#include <util/crc16.h> // _crc_ccitt_update
|
|
#include "autoconf.h" // CONFIG_AVR_STACK_SIZE
|
|
#include "board/misc.h" // alloc_maxsize
|
|
#include "command.h" // shutdown
|
|
#include "compiler.h" // ALIGN
|
|
#include "sched.h" // sched_shutdown
|
|
|
|
// Optimized crc16_ccitt for the avr processor
|
|
uint16_t
|
|
crc16_ccitt(char *buf, uint8_t len)
|
|
{
|
|
uint16_t crc = 0xFFFF;
|
|
while (len--)
|
|
crc = _crc_ccitt_update(crc, *buf++);
|
|
return crc;
|
|
}
|
|
|
|
// Allocate an area of memory
|
|
void *
|
|
alloc_chunk(size_t size)
|
|
{
|
|
void *data = malloc(size);
|
|
if (!data)
|
|
shutdown("alloc_chunk failed");
|
|
memset(data, 0, size);
|
|
return data;
|
|
}
|
|
|
|
// Allocate an array of chunks
|
|
void *
|
|
alloc_chunks(size_t size, size_t count, size_t *avail)
|
|
{
|
|
uint16_t memend = ALIGN(AVR_STACK_POINTER_REG, 256);
|
|
__malloc_heap_end = (void*)memend - CONFIG_AVR_STACK_SIZE;
|
|
extern char *__brkval;
|
|
uint16_t maxsize = __malloc_heap_end - __brkval - 2;
|
|
if ((int16_t)maxsize < 0)
|
|
maxsize = 0;
|
|
if (count * size > maxsize)
|
|
count = maxsize / size;
|
|
if (!count)
|
|
shutdown("alloc_chunks failed");
|
|
*avail = count;
|
|
return alloc_chunk(count * size);
|
|
}
|