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mem.c
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33 lines (29 loc) · 980 Bytes
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#include "mem.h"
void memory_copy(u8 *source, u8 *dest, int nbytes) {
int i;
for (i = 0; i < nbytes; i++) {
*(dest + i) = *(source + i);
}
}
void memory_set(u8 *dest, u8 val, u32 len) {
u8 *temp = (u8 *)dest;
for ( ; len != 0; len--) *temp++ = val;
}
/* This should be computed at link time, but a hardcoded
* value is fine for now. Remember that our kernel starts
* at 0x1000 as defined on the Makefile */
u32 free_mem_addr = 0x10000;
/* Implementation is just a pointer to some free memory which
* keeps growing */
u32 kmalloc(u32 size, int align, u32 *phys_addr) {
/* Pages are aligned to 4K, or 0x1000 */
if (align == 1 && (free_mem_addr & 0xFFFFF000)) {
free_mem_addr &= 0xFFFFF000;
free_mem_addr += 0x1000;
}
/* Save also the physical address */
if (phys_addr) *phys_addr = free_mem_addr;
u32 ret = free_mem_addr;
free_mem_addr += size; /* Remember to increment the pointer */
return ret;
}