1 files changed, 112 insertions, 0 deletions
diff --git a/include/hw/register.h b/include/hw/register.h
new file mode 100644
index 0000000000..6a2bc756d1
--- /dev/null
+++ b/include/hw/register.h
@@ -0,0 +1,112 @@
+/*
+ * Register Definition API
+ *
+ * Copyright (c) 2016 Xilinx Inc.
+ * Copyright (c) 2013 Peter Crosthwaite <peter.crosthwaite@xilinx.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ */
+
+#ifndef REGISTER_H
+#define REGISTER_H
+
+#include "exec/memory.h"
+
+typedef struct RegisterInfo RegisterInfo;
+typedef struct RegisterAccessInfo RegisterAccessInfo;
+
+/**
+ * Access description for a register that is part of guest accessible device
+ * state.
+ *
+ * @name: String name of the register
+ * @ro: whether or not the bit is read-only
+ * @w1c: bits with the common write 1 to clear semantic.
+ * @reset: reset value.
+ * @cor: Bits that are clear on read
+ * @rsvd: Bits that are reserved and should not be changed
+ *
+ * @pre_write: Pre write callback. Passed the value that's to be written,
+ * immediately before the actual write. The returned value is what is written,
+ * giving the handler a chance to modify the written value.
+ * @post_write: Post write callback. Passed the written value. Most write side
+ * effects should be implemented here.
+ *
+ * @post_read: Post read callback. Passes the value that is about to be returned
+ * for a read. The return value from this function is what is ultimately read,
+ * allowing this function to modify the value before return to the client.
+ */
+
+struct RegisterAccessInfo {
+    const char *name;
+    uint64_t ro;
+    uint64_t w1c;
+    uint64_t reset;
+    uint64_t cor;
+    uint64_t rsvd;
+    uint64_t unimp;
+
+    uint64_t (*pre_write)(RegisterInfo *reg, uint64_t val);
+    void (*post_write)(RegisterInfo *reg, uint64_t val);
+
+    uint64_t (*post_read)(RegisterInfo *reg, uint64_t val);
+};
+
+/**
+ * A register that is part of guest accessible state
+ * @data: pointer to the register data. Will be cast
+ * to the relevant uint type depending on data_size.
+ * @data_size: Size of the register in bytes. Must be
+ * 1, 2, 4 or 8
+ *
+ * @access: Access description of this register
+ *
+ * @debug: Whether or not verbose debug is enabled
+ * @prefix: String prefix for log and debug messages
+ *
+ * @opaque: Opaque data for the register
+ */
+
+struct RegisterInfo {
+    /* <public> */
+    void *data;
+    int data_size;
+
+    const RegisterAccessInfo *access;
+
+    void *opaque;
+};
+
+/**
+ * write a value to a register, subject to its restrictions
+ * @reg: register to write to
+ * @val: value to write
+ * @we: write enable mask
+ * @prefix: The device prefix that should be printed before the register name
+ * @debug: Should the write operation debug information be printed?
+ */
+
+void register_write(RegisterInfo *reg, uint64_t val, uint64_t we,
+                    const char *prefix, bool debug);
+
+/**
+ * read a value from a register, subject to its restrictions
+ * @reg: register to read from
+ * @re: read enable mask
+ * @prefix: The device prefix that should be printed before the register name
+ * @debug: Should the read operation debug information be printed?
+ * returns: value read
+ */
+
+uint64_t register_read(RegisterInfo *reg, uint64_t re, const char* prefix,
+                       bool debug);
+
+/**
+ * reset a register
+ * @reg: register to reset
+ */
+
+void register_reset(RegisterInfo *reg);
+
+#endif