meillo@1: #include "mem.h"
meillo@1: #include "io.h"
meillo@1: 
meillo@1: 
meillo@1: void
meillo@1: initmem(unsigned int memstart)
meillo@1: {
meillo@1: 	unsigned int* p;
meillo@1: 	int step = 2*1024*1024;
meillo@1: 	unsigned int* zero = 0x0;
meillo@1: 
meillo@1: 
meillo@1: 	minmem = (unsigned char*)memstart;
meillo@1: 
meillo@1: 	/* disable cache */
meillo@1: 	__asm__ __volatile__ (
meillo@1: 		"movl %cr0, %eax\n\t"
meillo@1: 		"movl $0x60000000, %ebx\n\t"
meillo@1: 		"orl %ebx, %eax\n\t"
meillo@1: 		"movl %eax, %cr0"
meillo@1: 	);
meillo@1: 
meillo@1: 	/* test mem size */
meillo@1: 	p = (unsigned int*) ((unsigned int)minmem/sizeof(char));
meillo@1: 	do {
meillo@1: 		p += step;
meillo@1: 		*p = 0xf0f0f0f0;
meillo@1: 	} while (*p == 0xf0f0f0f0);
meillo@1: 	maxmem = (unsigned char*)p;
meillo@1: 
meillo@1: 	/* test mem mirroring */
meillo@1: 	p = 0;
meillo@1: 	*p = 0;
meillo@1: 	p++;
meillo@1: 	while (p < (unsigned int*)minmem) {
meillo@1: 		p = (unsigned int*) ((unsigned int)p * 2);
meillo@1: 	}
meillo@1: 	while (p < (unsigned int*)maxmem) {
meillo@1: 		*p = 0xf0f0f0f0;
meillo@1: 		if (*zero == 0xf0f0f0f0) {
meillo@1: 			maxmem = (unsigned char*)p;
meillo@1: 			break;
meillo@1: 		}
meillo@1: 		p = (unsigned int*) ((unsigned int)p * 2);
meillo@1: 	}
meillo@1: 
meillo@1: 	/* enable cache again */
meillo@1: 	__asm__ __volatile__ (
meillo@1: 		"movl %cr0, %eax\n\t"
meillo@1: 		"movl $0x60000000, %ebx \n\t"
meillo@1: 		"negl %ebx\n\t"
meillo@1: 		"andl %ebx, %eax\n\t"
meillo@1: 		"movl %eax, %cr0"
meillo@1: 	);
meillo@1: 
meillo@1: 	/* min, max */
meillo@1: 	printf("mem: start=%p end=%p size=%p\n", minmem, maxmem, (void*)(maxmem-minmem));
meillo@1: 
meillo@1: 	/* init heap */
meillo@1: 	newp = minmem;
meillo@1: }
meillo@1: 
meillo@1: 
meillo@1: void*
meillo@1: malloc(unsigned int size)
meillo@1: {
meillo@1: 	if (newp + size > maxmem) {
meillo@1: 		printf("Fatal error: memory exhausted!\n");
meillo@1: 		while (1) {
meillo@1: 		}
meillo@1: 	}
meillo@1: 	newp += size;
meillo@1: 	return newp - size;
meillo@1: }