/* * arch/cris/mm/ioremap.c * * Re-map IO memory to kernel address space so that we can access it. * Needed for memory-mapped I/O devices mapped outside our normal DRAM * window (that is, all memory-mapped I/O devices). * * (C) Copyright 1995 1996 Linus Torvalds * CRIS-port by Axis Communications AB */ #include <linux/vmalloc.h> #include <linux/io.h> #include <asm/pgalloc.h> #include <arch/memmap.h> /* * Generic mapping function (not visible outside): */ /* * Remap an arbitrary physical address space into the kernel virtual * address space. Needed when the kernel wants to access high addresses * directly. * * NOTE! We need to allow non-page-aligned mappings too: we will obviously * have to convert them into an offset in a page-aligned mapping, but the * caller shouldn't need to know that small detail. */ void __iomem * __ioremap_prot(unsigned long phys_addr, unsigned long size, pgprot_t prot) { void __iomem * addr; struct vm_struct * area; unsigned long offset, last_addr; /* Don't allow wraparound or zero size */ last_addr = phys_addr + size - 1; if (!size || last_addr < phys_addr) return NULL; /* * Mappings have to be page-aligned */ offset = phys_addr & ~PAGE_MASK; phys_addr &= PAGE_MASK; size = PAGE_ALIGN(last_addr+1) - phys_addr; /* * Ok, go for it.. */ area = get_vm_area(size, VM_IOREMAP); if (!area) return NULL; addr = (void __iomem *)area->addr; if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size, phys_addr, prot)) { vfree((void __force *)addr); return NULL; } return (void __iomem *) (offset + (char __iomem *)addr); } void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags) { return __ioremap_prot(phys_addr, size, __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | _PAGE_GLOBAL | _PAGE_KERNEL | flags)); } /** * ioremap_nocache - map bus memory into CPU space * @offset: bus address of the memory * @size: size of the resource to map * * Must be freed with iounmap. */ void __iomem *ioremap_nocache(unsigned long phys_addr, unsigned long size) { return __ioremap(phys_addr | MEM_NON_CACHEABLE, size, 0); } EXPORT_SYMBOL(ioremap_nocache); void iounmap(volatile void __iomem *addr) { if (addr > high_memory) return vfree((void *) (PAGE_MASK & (unsigned long) addr)); }