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34 lines
1.0 KiB
C
34 lines
1.0 KiB
C
#include "mem.h"
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void memory_copy(uint8_t *source, uint8_t *dest, int nbytes) {
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int i;
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for (i = 0; i < nbytes; i++) {
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*(dest + i) = *(source + i);
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}
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}
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void memory_set(uint8_t *dest, uint8_t val, uint32_t len) {
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uint8_t *temp = (uint8_t *)dest;
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for ( ; len != 0; len--) *temp++ = val;
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}
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/* This should be computed at link time, but a hardcoded
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* value is fine for now. Remember that our kernel starts
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* at 0x1000 as defined on the Makefile */
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uint32_t free_mem_addr = 0x10000;
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/* Implementation is just a pointer to some free memory which
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* keeps growing */
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uint32_t kmalloc(size_t size, int align, uint32_t *phys_addr) {
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/* Pages are aligned to 4K, or 0x1000 */
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if (align == 1 && (free_mem_addr & 0xFFFFF000)) {
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free_mem_addr &= 0xFFFFF000;
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free_mem_addr += 0x1000;
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}
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/* Save also the physical address */
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if (phys_addr) *phys_addr = free_mem_addr;
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uint32_t ret = free_mem_addr;
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free_mem_addr += size; /* Remember to increment the pointer */
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return ret;
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}
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