linux/arch/s390/mm/mem_detect.c

66 lines
1.5 KiB
C

/*
* Copyright IBM Corp. 2008, 2009
*
* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/memblock.h>
#include <linux/init.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <asm/ipl.h>
#include <asm/sclp.h>
#include <asm/setup.h>
#define ADDR2G (1ULL << 31)
#define CHUNK_READ_WRITE 0
#define CHUNK_READ_ONLY 1
static inline void memblock_physmem_add(phys_addr_t start, phys_addr_t size)
{
memblock_add_range(&memblock.memory, start, size, 0, 0);
memblock_add_range(&memblock.physmem, start, size, 0, 0);
}
void __init detect_memory_memblock(void)
{
unsigned long long memsize, rnmax, rzm;
unsigned long addr, size;
int type;
rzm = sclp_get_rzm();
rnmax = sclp_get_rnmax();
memsize = rzm * rnmax;
if (!rzm)
rzm = 1ULL << 17;
if (IS_ENABLED(CONFIG_32BIT)) {
rzm = min(ADDR2G, rzm);
memsize = min(ADDR2G, memsize);
}
max_physmem_end = memsize;
addr = 0;
/* keep memblock lists close to the kernel */
memblock_set_bottom_up(true);
do {
size = 0;
type = tprot(addr);
do {
size += rzm;
if (max_physmem_end && addr + size >= max_physmem_end)
break;
} while (type == tprot(addr + size));
if (type == CHUNK_READ_WRITE || type == CHUNK_READ_ONLY) {
if (max_physmem_end && (addr + size > max_physmem_end))
size = max_physmem_end - addr;
memblock_physmem_add(addr, size);
}
addr += size;
} while (addr < max_physmem_end);
memblock_set_bottom_up(false);
if (!max_physmem_end)
max_physmem_end = memblock_end_of_DRAM();
}