1 files changed, 48 insertions, 0 deletions
diff --git a/arch/openrisc/mm/ioremap.c b/arch/openrisc/mm/ioremap.c
new file mode 100644
index 0000000000..f59ea4c10b
--- /dev/null
+++ b/arch/openrisc/mm/ioremap.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC ioremap.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others.  All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ */
+
+#include <linux/vmalloc.h>
+#include <linux/io.h>
+#include <linux/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/fixmap.h>
+#include <asm/bug.h>
+#include <linux/sched.h>
+#include <asm/tlbflush.h>
+
+extern int mem_init_done;
+
+/*
+ * OK, this one's a bit tricky... ioremap can get called before memory is
+ * initialized (early serial console does this) and will want to alloc a page
+ * for its mapping.  No userspace pages will ever get allocated before memory
+ * is initialized so this applies only to kernel pages.  In the event that
+ * this is called before memory is initialized we allocate the page using
+ * the memblock infrastructure.
+ */
+
+pte_t __ref *pte_alloc_one_kernel(struct mm_struct *mm)
+{
+	pte_t *pte;
+
+	if (likely(mem_init_done)) {
+		pte = (pte_t *)get_zeroed_page(GFP_KERNEL);
+	} else {
+		pte = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
+		if (!pte)
+			panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
+			      __func__, PAGE_SIZE, PAGE_SIZE);
+	}
+
+	return pte;
+}