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-rw-r--r--arch/parisc/mm/ioremap.c207
1 files changed, 207 insertions, 0 deletions
diff --git a/arch/parisc/mm/ioremap.c b/arch/parisc/mm/ioremap.c
new file mode 100644
index 00000000000..f2df502cdae
--- /dev/null
+++ b/arch/parisc/mm/ioremap.c
@@ -0,0 +1,207 @@
+/*
+ * arch/parisc/mm/ioremap.c
+ *
+ * Re-map IO memory to kernel address space so that we can access it.
+ * This is needed for high PCI addresses that aren't mapped in the
+ * 640k-1MB IO memory area on PC's
+ *
+ * (C) Copyright 1995 1996 Linus Torvalds
+ * (C) Copyright 2001 Helge Deller <deller@gmx.de>
+ */
+
+#include <linux/vmalloc.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <asm/io.h>
+#include <asm/pgalloc.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;
+
+ address &= ~PMD_MASK;
+ end = address + size;
+ if (end > PMD_SIZE)
+ end = PMD_SIZE;
+ if (address >= end)
+ BUG();
+ do {
+ if (!pte_none(*pte)) {
+ printk(KERN_ERR "remap_area_pte: page already exists\n");
+ BUG();
+ }
+ set_pte(pte, mk_pte_phys(phys_addr, __pgprot(_PAGE_PRESENT | _PAGE_RW |
+ _PAGE_DIRTY | _PAGE_ACCESSED | flags)));
+ address += PAGE_SIZE;
+ phys_addr += PAGE_SIZE;
+ 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(NULL, 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;
+}
+
+#if (USE_HPPA_IOREMAP)
+static 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(&init_mm, address);
+ flush_cache_all();
+ if (address >= end)
+ BUG();
+ spin_lock(&init_mm.page_table_lock);
+ do {
+ pmd_t *pmd;
+ pmd = pmd_alloc(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;
+}
+#endif /* USE_HPPA_IOREMAP */
+
+#ifdef CONFIG_DEBUG_IOREMAP
+static unsigned long last = 0;
+
+void gsc_bad_addr(unsigned long addr)
+{
+ if (time_after(jiffies, last + HZ*10)) {
+ printk("gsc_foo() called with bad address 0x%lx\n", addr);
+ dump_stack();
+ last = jiffies;
+ }
+}
+EXPORT_SYMBOL(gsc_bad_addr);
+
+void __raw_bad_addr(const volatile void __iomem *addr)
+{
+ if (time_after(jiffies, last + HZ*10)) {
+ printk("__raw_foo() called with bad address 0x%p\n", addr);
+ dump_stack();
+ last = jiffies;
+ }
+}
+EXPORT_SYMBOL(__raw_bad_addr);
+#endif
+
+/*
+ * 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(unsigned long phys_addr, unsigned long size, unsigned long flags)
+{
+#if !(USE_HPPA_IOREMAP)
+
+ unsigned long end = phys_addr + size - 1;
+ /* Support EISA addresses */
+ if ((phys_addr >= 0x00080000 && end < 0x000fffff)
+ || (phys_addr >= 0x00500000 && end < 0x03bfffff)) {
+ phys_addr |= 0xfc000000;
+ }
+
+#ifdef CONFIG_DEBUG_IOREMAP
+ return (void __iomem *)(phys_addr - (0x1UL << NYBBLE_SHIFT));
+#else
+ return (void __iomem *)phys_addr;
+#endif
+
+#else
+ void * 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;
+
+ /*
+ * Don't allow anybody to remap normal RAM that we're using..
+ */
+ if (phys_addr < virt_to_phys(high_memory)) {
+ char *t_addr, *t_end;
+ struct page *page;
+
+ t_addr = __va(phys_addr);
+ t_end = t_addr + (size - 1);
+
+ for(page = virt_to_page(t_addr); page <= virt_to_page(t_end); page++)
+ if(!PageReserved(page))
+ return NULL;
+ }
+
+ /*
+ * Mappings have to be page-aligned
+ */
+ offset = phys_addr & ~PAGE_MASK;
+ phys_addr &= PAGE_MASK;
+ size = PAGE_ALIGN(last_addr) - phys_addr;
+
+ /*
+ * Ok, go for it..
+ */
+ area = get_vm_area(size, VM_IOREMAP);
+ if (!area)
+ return NULL;
+ addr = area->addr;
+ if (remap_area_pages((unsigned long) addr, phys_addr, size, flags)) {
+ vfree(addr);
+ return NULL;
+ }
+ return (void __iomem *) (offset + (char *)addr);
+#endif
+}
+
+void iounmap(void __iomem *addr)
+{
+#if !(USE_HPPA_IOREMAP)
+ return;
+#else
+ if (addr > high_memory)
+ return vfree((void *) (PAGE_MASK & (unsigned long __force) addr));
+#endif
+}