1 files changed, 94 insertions, 0 deletions
diff --git a/include/lib/utils.h b/include/lib/utils.h
new file mode 100644
index 0000000..ce76de2
--- /dev/null
+++ b/include/lib/utils.h
@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2016-2019, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef UTILS_H
+#define UTILS_H
+
+/*
+ * C code should be put in this part of the header to avoid breaking ASM files
+ * or linker scripts including it.
+ */
+#if !(defined(__LINKER__) || defined(__ASSEMBLER__))
+
+#include <stddef.h>
+#include <stdint.h>
+
+typedef struct mem_region {
+	uintptr_t base;
+	size_t nbytes;
+} mem_region_t;
+
+/*
+ * zero_normalmem all the regions defined in tbl.
+ */
+void clear_mem_regions(mem_region_t *tbl, size_t nregions);
+
+/*
+ * zero_normalmem all the regions defined in region. It dynamically
+ * maps chunks of 'chunk_size' in 'va' virtual address and clears them.
+ * For this reason memory regions must be multiple of chunk_size and
+ * must be aligned to it as well. chunk_size and va can be selected
+ * in a way that they minimize the number of entries used in the
+ * translation tables.
+ */
+void clear_map_dyn_mem_regions(struct mem_region *regions,
+			       size_t nregions,
+			       uintptr_t va,
+			       size_t chunk);
+
+/*
+ * checks that a region (addr + nbytes-1) of memory is totally covered by
+ * one of the regions defined in tbl. Caller must ensure that (addr+nbytes-1)
+ * doesn't overflow.
+ */
+int mem_region_in_array_chk(mem_region_t *tbl, size_t nregions,
+			    uintptr_t addr, size_t nbytes);
+
+/*
+ * Fill a region of normal memory of size "length" in bytes with zero bytes.
+ *
+ * WARNING: This function can only operate on normal memory. This means that
+ *          the MMU must be enabled when using this function. Otherwise, use
+ *          zeromem.
+ */
+void zero_normalmem(void *mem, u_register_t length);
+
+/*
+ * Fill a region of memory of size "length" in bytes with null bytes.
+ *
+ * Unlike zero_normalmem, this function has no restriction on the type of
+ * memory targeted and can be used for any device memory as well as normal
+ * memory. This function must be used instead of zero_normalmem when MMU is
+ * disabled.
+ *
+ * NOTE: When data cache and MMU are enabled, prefer zero_normalmem for faster
+ *       zeroing.
+ */
+void zeromem(void *mem, u_register_t length);
+
+/*
+ * Utility function to return the address of a symbol. By default, the
+ * compiler generates adr/adrp instruction pair to return the reference
+ * to the symbol and this utility is used to override this compiler
+ * generated to code to use `ldr` instruction.
+ *
+ * This helps when Position Independent Executable needs to reference a symbol
+ * which is constant and does not depend on the execute address of the binary.
+ */
+#define DEFINE_LOAD_SYM_ADDR(_name)		\
+static inline u_register_t load_addr_## _name(void)			\
+{									\
+	u_register_t v;							\
+	__asm__ volatile ("ldr %0, =" #_name : "=r" (v) : "X" (#_name));\
+	return v;							\
+}
+
+/* Helper to invoke the function defined by DEFINE_LOAD_SYM_ADDR() */
+#define LOAD_ADDR_OF(_name)	(typeof(_name) *) load_addr_## _name()
+
+#endif /* !(defined(__LINKER__) || defined(__ASSEMBLER__)) */
+
+#endif /* UTILS_H */