xtensa: support ioremap for memory outside KIO region

Map physical memory outside KIO region into the vmalloc area.
Unmap it with vunmap.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

1 files changed, 68 insertions, 0 deletions

diff --git a/arch/xtensa/mm/ioremap.c b/arch/xtensa/mm/ioremap.c
new file mode 100644
index 000000000000..d89c3c5fd962
--- /dev/null
+++ b/arch/xtensa/mm/ioremap.c
@@ -0,0 +1,68 @@
+/*
+ * ioremap implementation.
+ *
+ * Copyright (C) 2015 Cadence Design Systems Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/io.h>
+#include <linux/vmalloc.h>
+#include <asm/cacheflush.h>
+#include <asm/io.h>
+#include <asm/pgtable.h>
+
+static void __iomem *xtensa_ioremap(unsigned long paddr, unsigned long size,
+				    pgprot_t prot)
+{
+	unsigned long offset = paddr & ~PAGE_MASK;
+	unsigned long pfn = __phys_to_pfn(paddr);
+	struct vm_struct *area;
+	unsigned long vaddr;
+	int err;
+
+	paddr &= PAGE_MASK;
+
+	WARN_ON(pfn_valid(pfn));
+
+	size = PAGE_ALIGN(offset + size);
+
+	area = get_vm_area(size, VM_IOREMAP);
+	if (!area)
+		return NULL;
+
+	vaddr = (unsigned long)area->addr;
+	area->phys_addr = paddr;
+
+	err = ioremap_page_range(vaddr, vaddr + size, paddr, prot);
+
+	if (err) {
+		vunmap((void *)vaddr);
+		return NULL;
+	}
+
+	flush_cache_vmap(vaddr, vaddr + size);
+	return (void __iomem *)(offset + vaddr);
+}
+
+void __iomem *xtensa_ioremap_nocache(unsigned long addr, unsigned long size)
+{
+	return xtensa_ioremap(addr, size, pgprot_noncached(PAGE_KERNEL));
+}
+EXPORT_SYMBOL(xtensa_ioremap_nocache);
+
+void __iomem *xtensa_ioremap_cache(unsigned long addr, unsigned long size)
+{
+	return xtensa_ioremap(addr, size, PAGE_KERNEL);
+}
+EXPORT_SYMBOL(xtensa_ioremap_cache);
+
+void xtensa_iounmap(volatile void __iomem *io_addr)
+{
+	void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
+
+	vunmap(addr);
+}
+EXPORT_SYMBOL(xtensa_iounmap);