-/* $Id: ioremap.c,v 1.9 2004/02/25 04:59:10 lethal Exp $
- *
+/*
* arch/sh/mm/ioremap.c
*
* Re-map IO memory to kernel address space so that we can access it.
* 640k-1MB IO memory area on PC's
*
* (C) Copyright 1995 1996 Linus Torvalds
+ * (C) Copyright 2005, 2006 Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
*/
-
#include <linux/vmalloc.h>
+#include <linux/module.h>
#include <linux/mm.h>
-#include <asm/io.h>
+#include <linux/pci.h>
+#include <linux/io.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
+#include <asm/addrspace.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
-static inline void remap_area_pte(pte_t * pte, unsigned long address,
- unsigned long size, unsigned long phys_addr, unsigned long flags)
-{
- unsigned long end;
- unsigned long pfn;
- pgprot_t pgprot = __pgprot(_PAGE_PRESENT | _PAGE_RW |
- _PAGE_DIRTY | _PAGE_ACCESSED |
- _PAGE_HW_SHARED | _PAGE_FLAGS_HARD | flags);
-
- address &= ~PMD_MASK;
- end = address + size;
- if (end > PMD_SIZE)
- end = PMD_SIZE;
- if (address >= end)
- BUG();
- pfn = phys_addr >> PAGE_SHIFT;
- do {
- if (!pte_none(*pte)) {
- printk("remap_area_pte: page already exists\n");
- BUG();
- }
- set_pte(pte, pfn_pte(pfn, pgprot));
- address += PAGE_SIZE;
- pfn++;
- pte++;
- } while (address && (address < end));
-}
-
-static inline int remap_area_pmd(pmd_t * pmd, unsigned long address,
- unsigned long size, unsigned long phys_addr, unsigned long flags)
-{
- unsigned long end;
-
- address &= ~PGDIR_MASK;
- end = address + size;
- if (end > PGDIR_SIZE)
- end = PGDIR_SIZE;
- phys_addr -= address;
- if (address >= end)
- BUG();
- do {
- pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
- if (!pte)
- return -ENOMEM;
- remap_area_pte(pte, address, end - address, address + phys_addr, flags);
- address = (address + PMD_SIZE) & PMD_MASK;
- pmd++;
- } while (address && (address < end));
- return 0;
-}
-
-int remap_area_pages(unsigned long address, unsigned long phys_addr,
- unsigned long size, unsigned long flags)
-{
- int error;
- pgd_t * dir;
- unsigned long end = address + size;
-
- phys_addr -= address;
- dir = pgd_offset_k(address);
- flush_cache_all();
- if (address >= end)
- BUG();
- spin_lock(&init_mm.page_table_lock);
- do {
- pmd_t *pmd;
- pmd = pmd_alloc(&init_mm, dir, address);
- error = -ENOMEM;
- if (!pmd)
- break;
- if (remap_area_pmd(pmd, address, end - address,
- phys_addr + address, flags))
- break;
- error = 0;
- address = (address + PGDIR_SIZE) & PGDIR_MASK;
- dir++;
- } while (address && (address < end));
- spin_unlock(&init_mm.page_table_lock);
- flush_tlb_all();
- return error;
-}
-
-/*
- * 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
* have to convert them into an offset in a page-aligned mapping, but the
* caller shouldn't need to know that small detail.
*/
-void * p3_ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
+void __iomem *__ioremap(unsigned long phys_addr, unsigned long size,
+ unsigned long flags)
{
- void * addr;
struct vm_struct * area;
- unsigned long offset, last_addr;
+ unsigned long offset, last_addr, addr, orig_addr;
+ pgprot_t pgprot;
/* Don't allow wraparound or zero size */
last_addr = phys_addr + size - 1;
* Don't remap the low PCI/ISA area, it's always mapped..
*/
if (phys_addr >= 0xA0000 && last_addr < 0x100000)
- return phys_to_virt(phys_addr);
+ return (void __iomem *)phys_to_virt(phys_addr);
+
+ /*
+ * If we're on an SH7751 or SH7780 PCI controller, PCI memory is
+ * mapped at the end of the address space (typically 0xfd000000)
+ * in a non-translatable area, so mapping through page tables for
+ * this area is not only pointless, but also fundamentally
+ * broken. Just return the physical address instead.
+ *
+ * For boards that map a small PCI memory aperture somewhere in
+ * P1/P2 space, ioremap() will already do the right thing,
+ * and we'll never get this far.
+ */
+ if (is_pci_memaddr(phys_addr) && is_pci_memaddr(last_addr))
+ return (void __iomem *)phys_addr;
/*
* Don't allow anybody to remap normal RAM that we're using..
if (!area)
return NULL;
area->phys_addr = phys_addr;
- addr = area->addr;
- if (remap_area_pages((unsigned long) addr, phys_addr, size, flags)) {
- vunmap(addr);
- return NULL;
+ orig_addr = addr = (unsigned long)area->addr;
+
+#ifdef CONFIG_32BIT
+ /*
+ * First try to remap through the PMB once a valid VMA has been
+ * established. Smaller allocations (or the rest of the size
+ * remaining after a PMB mapping due to the size not being
+ * perfectly aligned on a PMB size boundary) are then mapped
+ * through the UTLB using conventional page tables.
+ *
+ * PMB entries are all pre-faulted.
+ */
+ if (unlikely(size >= 0x1000000)) {
+ unsigned long mapped = pmb_remap(addr, phys_addr, size, flags);
+
+ if (likely(mapped)) {
+ addr += mapped;
+ phys_addr += mapped;
+ size -= mapped;
+ }
}
- return (void *) (offset + (char *)addr);
+#endif
+
+ pgprot = __pgprot(pgprot_val(PAGE_KERNEL_NOCACHE) | flags);
+ if (likely(size))
+ if (ioremap_page_range(addr, addr + size, phys_addr, pgprot)) {
+ vunmap((void *)orig_addr);
+ return NULL;
+ }
+
+ return (void __iomem *)(offset + (char *)orig_addr);
}
+EXPORT_SYMBOL(__ioremap);
-void p3_iounmap(void *addr)
+void __iounmap(void __iomem *addr)
{
- if (addr > high_memory)
- vfree((void *)(PAGE_MASK & (unsigned long)addr));
+ unsigned long vaddr = (unsigned long __force)addr;
+ struct vm_struct *p;
+
+ if (PXSEG(vaddr) < P3SEG || is_pci_memaddr(vaddr))
+ return;
+
+#ifdef CONFIG_32BIT
+ /*
+ * Purge any PMB entries that may have been established for this
+ * mapping, then proceed with conventional VMA teardown.
+ *
+ * XXX: Note that due to the way that remove_vm_area() does
+ * matching of the resultant VMA, we aren't able to fast-forward
+ * the address past the PMB space until the end of the VMA where
+ * the page tables reside. As such, unmap_vm_area() will be
+ * forced to linearly scan over the area until it finds the page
+ * tables where PTEs that need to be unmapped actually reside,
+ * which is far from optimal. Perhaps we need to use a separate
+ * VMA for the PMB mappings?
+ * -- PFM.
+ */
+ pmb_unmap(vaddr);
+#endif
+
+ p = remove_vm_area((void *)(vaddr & PAGE_MASK));
+ if (!p) {
+ printk(KERN_ERR "%s: bad address %p\n", __FUNCTION__, addr);
+ return;
+ }
+
+ kfree(p);
}
+EXPORT_SYMBOL(__iounmap);