/*
* Limit the memory size that was specified via FDT.
*/
static int __init early_mem(char *p)
{
phys_addr_t limit;
if (!p)
return 1;
limit = memparse(p, &p) & PAGE_MASK;
pr_notice("Memory limited to %lldMB\n", limit >> 20);
memblock_enforce_memory_limit(limit);
return 0;
}
/*
* MMU_init sets up the basic memory mappings for the kernel,
* including both RAM and possibly some I/O regions,
* and sets up the page tables and the MMU hardware ready to go.
*/
void __init MMU_init(void)
{
if (ppc_md.progress)
ppc_md.progress("MMU:enter", 0x111);
/* parse args from command line */
MMU_setup();
/*
* Reserve gigantic pages for hugetlb. This MUST occur before
* lowmem_end_addr is initialized below.
*/
reserve_hugetlb_gpages();
if (memblock.memory.cnt > 1) {
#ifndef CONFIG_WII
memblock_enforce_memory_limit(memblock.memory.regions[0].size);
printk(KERN_WARNING "Only using first contiguous memory region");
#else
wii_memory_fixups();
#endif
}
total_lowmem = total_memory = memblock_end_of_DRAM() - memstart_addr;
lowmem_end_addr = memstart_addr + total_lowmem;
#ifdef CONFIG_FSL_BOOKE
/* Freescale Book-E parts expect lowmem to be mapped by fixed TLB
* entries, so we need to adjust lowmem to match the amount we can map
* in the fixed entries */
adjust_total_lowmem();
#endif /* CONFIG_FSL_BOOKE */
if (total_lowmem > __max_low_memory) {
total_lowmem = __max_low_memory;
lowmem_end_addr = memstart_addr + total_lowmem;
#ifndef CONFIG_HIGHMEM
total_memory = total_lowmem;
memblock_enforce_memory_limit(total_lowmem);
#endif /* CONFIG_HIGHMEM */
}
/* Initialize the MMU hardware */
if (ppc_md.progress)
ppc_md.progress("MMU:hw init", 0x300);
MMU_init_hw();
/* Map in all of RAM starting at KERNELBASE */
if (ppc_md.progress)
ppc_md.progress("MMU:mapin", 0x301);
mapin_ram();
/* Initialize early top-down ioremap allocator */
ioremap_bot = IOREMAP_TOP;
/* Map in I/O resources */
if (ppc_md.progress)
ppc_md.progress("MMU:setio", 0x302);
if (ppc_md.progress)
ppc_md.progress("MMU:exit", 0x211);
/* From now on, btext is no longer BAT mapped if it was at all */
#ifdef CONFIG_BOOTX_TEXT
btext_unmap();
#endif
/* Shortly after that, the entire linear mapping will be available */
memblock_set_current_limit(lowmem_end_addr);
}
