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-rw-r--r--arch/ia64/mm/ioremap.c123
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/ia64/mm/ioremap.c b/arch/ia64/mm/ioremap.c
new file mode 100644
index 000000000..55fd3eb75
--- /dev/null
+++ b/arch/ia64/mm/ioremap.c
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * (c) Copyright 2006, 2007 Hewlett-Packard Development Company, L.P.
+ * Bjorn Helgaas <bjorn.helgaas@hp.com>
+ */
+
+#include <linux/compiler.h>
+#include <linux/module.h>
+#include <linux/efi.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <asm/io.h>
+#include <asm/meminit.h>
+
+static inline void __iomem *
+__ioremap_uc(unsigned long phys_addr)
+{
+ return (void __iomem *) (__IA64_UNCACHED_OFFSET | phys_addr);
+}
+
+void __iomem *
+early_ioremap (unsigned long phys_addr, unsigned long size)
+{
+ u64 attr;
+ attr = kern_mem_attribute(phys_addr, size);
+ if (attr & EFI_MEMORY_WB)
+ return (void __iomem *) phys_to_virt(phys_addr);
+ return __ioremap_uc(phys_addr);
+}
+
+void __iomem *
+ioremap (unsigned long phys_addr, unsigned long size)
+{
+ void __iomem *addr;
+ struct vm_struct *area;
+ unsigned long offset;
+ pgprot_t prot;
+ u64 attr;
+ unsigned long gran_base, gran_size;
+ unsigned long page_base;
+
+ /*
+ * For things in kern_memmap, we must use the same attribute
+ * as the rest of the kernel. For more details, see
+ * Documentation/ia64/aliasing.rst.
+ */
+ attr = kern_mem_attribute(phys_addr, size);
+ if (attr & EFI_MEMORY_WB)
+ return (void __iomem *) phys_to_virt(phys_addr);
+ else if (attr & EFI_MEMORY_UC)
+ return __ioremap_uc(phys_addr);
+
+ /*
+ * Some chipsets don't support UC access to memory. If
+ * WB is supported for the whole granule, we prefer that.
+ */
+ gran_base = GRANULEROUNDDOWN(phys_addr);
+ gran_size = GRANULEROUNDUP(phys_addr + size) - gran_base;
+ if (efi_mem_attribute(gran_base, gran_size) & EFI_MEMORY_WB)
+ return (void __iomem *) phys_to_virt(phys_addr);
+
+ /*
+ * WB is not supported for the whole granule, so we can't use
+ * the region 7 identity mapping. If we can safely cover the
+ * area with kernel page table mappings, we can use those
+ * instead.
+ */
+ page_base = phys_addr & PAGE_MASK;
+ size = PAGE_ALIGN(phys_addr + size) - page_base;
+ if (efi_mem_attribute(page_base, size) & EFI_MEMORY_WB) {
+ prot = PAGE_KERNEL;
+
+ /*
+ * Mappings have to be page-aligned
+ */
+ offset = phys_addr & ~PAGE_MASK;
+ phys_addr &= PAGE_MASK;
+
+ /*
+ * Ok, go for it..
+ */
+ area = get_vm_area(size, VM_IOREMAP);
+ if (!area)
+ return NULL;
+
+ area->phys_addr = phys_addr;
+ addr = (void __iomem *) area->addr;
+ if (ioremap_page_range((unsigned long) addr,
+ (unsigned long) addr + size, phys_addr, prot)) {
+ vunmap((void __force *) addr);
+ return NULL;
+ }
+
+ return (void __iomem *) (offset + (char __iomem *)addr);
+ }
+
+ return __ioremap_uc(phys_addr);
+}
+EXPORT_SYMBOL(ioremap);
+
+void __iomem *
+ioremap_uc(unsigned long phys_addr, unsigned long size)
+{
+ if (kern_mem_attribute(phys_addr, size) & EFI_MEMORY_WB)
+ return NULL;
+
+ return __ioremap_uc(phys_addr);
+}
+EXPORT_SYMBOL(ioremap_uc);
+
+void
+early_iounmap (volatile void __iomem *addr, unsigned long size)
+{
+}
+
+void
+iounmap (volatile void __iomem *addr)
+{
+ if (REGION_NUMBER(addr) == RGN_GATE)
+ vunmap((void *) ((unsigned long) addr & PAGE_MASK));
+}
+EXPORT_SYMBOL(iounmap);