|
@@ -0,0 +1,156 @@
|
|
|
+/*
|
|
|
+ * linux/arch/arm/mm/ioremap.c
|
|
|
+ *
|
|
|
+ * Re-map IO memory to kernel address space so that we can access it.
|
|
|
+ *
|
|
|
+ * (C) Copyright 1995 1996 Linus Torvalds
|
|
|
+ *
|
|
|
+ * Hacked for ARM by Phil Blundell <philb@gnu.org>
|
|
|
+ * Hacked to allow all architectures to build, and various cleanups
|
|
|
+ * by Russell King
|
|
|
+ *
|
|
|
+ * This allows a driver to remap an arbitrary region of bus memory into
|
|
|
+ * virtual space. One should *only* use readl, writel, memcpy_toio and
|
|
|
+ * so on with such remapped areas.
|
|
|
+ *
|
|
|
+ * Because the ARM only has a 32-bit address space we can't address the
|
|
|
+ * whole of the (physical) PCI space at once. PCI huge-mode addressing
|
|
|
+ * allows us to circumvent this restriction by splitting PCI space into
|
|
|
+ * two 2GB chunks and mapping only one at a time into processor memory.
|
|
|
+ * We use MMU protection domains to trap any attempt to access the bank
|
|
|
+ * that is not currently mapped. (This isn't fully implemented yet.)
|
|
|
+ */
|
|
|
+#include <linux/module.h>
|
|
|
+#include <linux/errno.h>
|
|
|
+#include <linux/mm.h>
|
|
|
+#include <linux/vmalloc.h>
|
|
|
+#include <linux/io.h>
|
|
|
+#include <linux/sizes.h>
|
|
|
+
|
|
|
+#include <asm/cp15.h>
|
|
|
+#include <asm/cputype.h>
|
|
|
+#include <asm/cacheflush.h>
|
|
|
+#include <asm/mmu_context.h>
|
|
|
+#include <asm/pgalloc.h>
|
|
|
+#include <asm/tlbflush.h>
|
|
|
+#include <asm/system_info.h>
|
|
|
+
|
|
|
+#include <asm/mach/map.h>
|
|
|
+#include <asm/mach/pci.h>
|
|
|
+#include "mm.h"
|
|
|
+
|
|
|
+int ioremap_page(unsigned long virt, unsigned long phys,
|
|
|
+ const struct mem_type *mtype)
|
|
|
+{
|
|
|
+ return ioremap_page_range(virt, virt + PAGE_SIZE, phys,
|
|
|
+ __pgprot(mtype->prot_pte));
|
|
|
+}
|
|
|
+EXPORT_SYMBOL(ioremap_page);
|
|
|
+
|
|
|
+void __check_vmalloc_seq(struct mm_struct *mm)
|
|
|
+{
|
|
|
+ unsigned int seq;
|
|
|
+
|
|
|
+ do {
|
|
|
+ seq = init_mm.context.vmalloc_seq;
|
|
|
+ memcpy(pgd_offset(mm, VMALLOC_START),
|
|
|
+ pgd_offset_k(VMALLOC_START),
|
|
|
+ sizeof(pgd_t) * (pgd_index(VMALLOC_END) -
|
|
|
+ pgd_index(VMALLOC_START)));
|
|
|
+ mm->context.vmalloc_seq = seq;
|
|
|
+ } while (seq != init_mm.context.vmalloc_seq);
|
|
|
+}
|
|
|
+
|
|
|
+#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
|
|
|
+/*
|
|
|
+ * Section support is unsafe on SMP - If you iounmap and ioremap a region,
|
|
|
+ * the other CPUs will not see this change until their next context switch.
|
|
|
+ * Meanwhile, (eg) if an interrupt comes in on one of those other CPUs
|
|
|
+ * which requires the new ioremap'd region to be referenced, the CPU will
|
|
|
+ * reference the _old_ region.
|
|
|
+ *
|
|
|
+ * Note that get_vm_area_caller() allocates a guard 4K page, so we need to
|
|
|
+ * mask the size back to 1MB aligned or we will overflow in the loop below.
|
|
|
+ */
|
|
|
+static void unmap_area_sections(unsigned long virt, unsigned long size)
|
|
|
+{
|
|
|
+ unsigned long addr = virt, end = virt + (size & ~(SZ_1M - 1));
|
|
|
+ pgd_t *pgd;
|
|
|
+ pud_t *pud;
|
|
|
+ pmd_t *pmdp;
|
|
|
+
|
|
|
+ flush_cache_vunmap(addr, end);
|
|
|
+ pgd = pgd_offset_k(addr);
|
|
|
+ pud = pud_offset(pgd, addr);
|
|
|
+ pmdp = pmd_offset(pud, addr);
|
|
|
+ do {
|
|
|
+ pmd_t pmd = *pmdp;
|
|
|
+
|
|
|
+ if (!pmd_none(pmd)) {
|
|
|
+ /*
|
|
|
+ * Clear the PMD from the page table, and
|
|
|
+ * increment the vmalloc sequence so others
|
|
|
+ * notice this change.
|
|
|
+ *
|
|
|
+ * Note: this is still racy on SMP machines.
|
|
|
+ */
|
|
|
+ pmd_clear(pmdp);
|
|
|
+ init_mm.context.vmalloc_seq++;
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Free the page table, if there was one.
|
|
|
+ */
|
|
|
+ if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_TABLE)
|
|
|
+ pte_free_kernel(&init_mm, pmd_page_vaddr(pmd));
|
|
|
+ }
|
|
|
+
|
|
|
+ addr += PMD_SIZE;
|
|
|
+ pmdp += 2;
|
|
|
+ } while (addr < end);
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Ensure that the active_mm is up to date - we want to
|
|
|
+ * catch any use-after-iounmap cases.
|
|
|
+ */
|
|
|
+ if (current->active_mm->context.vmalloc_seq != init_mm.context.vmalloc_seq)
|
|
|
+ __check_vmalloc_seq(current->active_mm);
|
|
|
+
|
|
|
+ flush_tlb_kernel_range(virt, end);
|
|
|
+}
|
|
|
+
|
|
|
+static int
|
|
|
+remap_area_sections(unsigned long virt, unsigned long pfn,
|
|
|
+ size_t size, const struct mem_type *type)
|
|
|
+{
|
|
|
+ unsigned long addr = virt, end = virt + size;
|
|
|
+ pgd_t *pgd;
|
|
|
+ pud_t *pud;
|
|
|
+ pmd_t *pmd;
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Remove and free any PTE-based mapping, and
|
|
|
+ * sync the current kernel mapping.
|
|
|
+ */
|
|
|
+ unmap_area_sections(virt, size);
|
|
|
+
|
|
|
+ pgd = pgd_offset_k(addr);
|
|
|
+ pud = pud_offset(pgd, addr);
|
|
|
+ pmd = pmd_offset(pud, addr);
|
|
|
+ do {
|
|
|
+ pmd[0] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
|
|
|
+ pfn += SZ_1M >> PAGE_SHIFT;
|
|
|
+ pmd[1] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
|
|
|
+ pfn += SZ_1M >> PAGE_SHIFT;
|
|
|
+ flush_pmd_entry(pmd);
|
|
|
+
|
|
|
+ addr += PMD_SIZE;
|
|
|
+ pmd += 2;
|
|
|
+ } while (addr < end);
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+static int
|
|
|
+remap_area_supersections(unsigned long virt, unsigned long pfn,
|
|
|
+ size_t size, const struct mem_type *type)
|
|
|
+{
|