1 files changed, 81 insertions, 0 deletions
diff --git a/arch/microblaze/include/asm/flat.h b/arch/microblaze/include/asm/flat.h
new file mode 100644
index 000000000..79a749f4a
--- /dev/null
+++ b/arch/microblaze/include/asm/flat.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * uClinux flat-format executables
+ *
+ * Copyright (C) 2005 John Williams <jwilliams@itee.uq.edu.au>
+ */
+
+#ifndef _ASM_MICROBLAZE_FLAT_H
+#define _ASM_MICROBLAZE_FLAT_H
+
+#include <asm/unaligned.h>
+
+/*
+ * Microblaze works a little differently from other arches, because
+ * of the MICROBLAZE_64 reloc type. Here, a 32 bit address is split
+ * over two instructions, an 'imm' instruction which provides the top
+ * 16 bits, then the instruction "proper" which provides the low 16
+ * bits.
+ */
+
+/*
+ * Crack open a symbol reference and extract the address to be
+ * relocated. rp is a potentially unaligned pointer to the
+ * reference
+ */
+
+static inline int flat_get_addr_from_rp(u32 __user *rp, u32 relval, u32 flags,
+					u32 *addr)
+{
+	u32 *p = (__force u32 *)rp;
+
+	/* Is it a split 64/32 reference? */
+	if (relval & 0x80000000) {
+		/* Grab the two halves of the reference */
+		u32 val_hi, val_lo;
+
+		val_hi = get_unaligned(p);
+		val_lo = get_unaligned(p+1);
+
+		/* Crack the address out */
+		*addr = ((val_hi & 0xffff) << 16) + (val_lo & 0xffff);
+	} else {
+		/* Get the address straight out */
+		*addr = get_unaligned(p);
+	}
+
+	return 0;
+}
+
+/*
+ * Insert an address into the symbol reference at rp. rp is potentially
+ * unaligned.
+ */
+
+static inline int
+flat_put_addr_at_rp(u32 __user *rp, u32 addr, u32 relval)
+{
+	u32 *p = (__force u32 *)rp;
+	/* Is this a split 64/32 reloc? */
+	if (relval & 0x80000000) {
+		/* Get the two "halves" */
+		unsigned long val_hi = get_unaligned(p);
+		unsigned long val_lo = get_unaligned(p + 1);
+
+		/* insert the address */
+		val_hi = (val_hi & 0xffff0000) | addr >> 16;
+		val_lo = (val_lo & 0xffff0000) | (addr & 0xffff);
+
+		/* store the two halves back into memory */
+		put_unaligned(val_hi, p);
+		put_unaligned(val_lo, p+1);
+	} else {
+		/* Put it straight in, no messing around */
+		put_unaligned(addr, p);
+	}
+	return 0;
+}
+
+#define	flat_get_relocate_addr(rel)	(rel & 0x7fffffff)
+
+#endif /* _ASM_MICROBLAZE_FLAT_H */