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-rw-r--r--arch/arm/include/asm/sparsemem.h26
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/arm/include/asm/sparsemem.h b/arch/arm/include/asm/sparsemem.h
new file mode 100644
index 0000000000..421e341533
--- /dev/null
+++ b/arch/arm/include/asm/sparsemem.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ASMARM_SPARSEMEM_H
+#define ASMARM_SPARSEMEM_H
+
+#include <asm/page.h>
+
+/*
+ * Two definitions are required for sparsemem:
+ *
+ * MAX_PHYSMEM_BITS: The number of physical address bits required
+ * to address the last byte of memory.
+ *
+ * SECTION_SIZE_BITS: The number of physical address bits to cover
+ * the maximum amount of memory in a section.
+ *
+ * Eg, if you have 2 banks of up to 64MB at 0x80000000, 0x84000000,
+ * then MAX_PHYSMEM_BITS is 32, SECTION_SIZE_BITS is 26.
+ *
+ * These can be overridden in your mach/memory.h.
+ */
+#if !defined(MAX_PHYSMEM_BITS) || !defined(SECTION_SIZE_BITS)
+#define MAX_PHYSMEM_BITS 36
+#define SECTION_SIZE_BITS 28
+#endif
+
+#endif