1 files changed, 59 insertions, 0 deletions
diff --git a/arch/xtensa/mm/highmem.c b/arch/xtensa/mm/highmem.c
new file mode 100644
index 0000000000..35c4f7d4a3
--- /dev/null
+++ b/arch/xtensa/mm/highmem.c
@@ -0,0 +1,59 @@
+/*
+ * High memory support for Xtensa architecture
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file "COPYING" in the main directory of
+ * this archive for more details.
+ *
+ * Copyright (C) 2014 Cadence Design Systems Inc.
+ */
+
+#include <linux/export.h>
+#include <linux/highmem.h>
+#include <asm/tlbflush.h>
+
+#if DCACHE_WAY_SIZE > PAGE_SIZE
+unsigned int last_pkmap_nr_arr[DCACHE_N_COLORS];
+wait_queue_head_t pkmap_map_wait_arr[DCACHE_N_COLORS];
+
+static void __init kmap_waitqueues_init(void)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(pkmap_map_wait_arr); ++i)
+		init_waitqueue_head(pkmap_map_wait_arr + i);
+}
+
+static inline enum fixed_addresses kmap_idx(int type, unsigned long color)
+{
+	int idx = (type + KM_MAX_IDX * smp_processor_id()) * DCACHE_N_COLORS;
+
+	/*
+	 * The fixmap operates top down, so the color offset needs to be
+	 * reverse as well.
+	 */
+	return idx + DCACHE_N_COLORS - 1 - color;
+}
+
+enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn)
+{
+	return kmap_idx(type, DCACHE_ALIAS(pfn << PAGE_SHIFT));
+}
+
+enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr)
+{
+	return kmap_idx(type, DCACHE_ALIAS(addr));
+}
+
+#else
+static inline void kmap_waitqueues_init(void) { }
+#endif
+
+void __init kmap_init(void)
+{
+	/* Check if this memory layout is broken because PKMAP overlaps
+	 * page table.
+	 */
+	BUILD_BUG_ON(PKMAP_BASE < TLBTEMP_BASE_1 + TLBTEMP_SIZE);
+	kmap_waitqueues_init();
+}