Add qemu 2.4.0

[kvmfornfv.git] / qemu / roms / ipxe / src / drivers / bitbash / bitbash.c

diff --git a/qemu/roms/ipxe/src/drivers/bitbash/bitbash.c b/qemu/roms/ipxe/src/drivers/bitbash/bitbash.c
new file mode 100644 (file)
index 0000000..23ca303
--- /dev/null
+++ b/qemu/roms/ipxe/src/drivers/bitbash/bitbash.c
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <ipxe/bitbash.h>
+
+/** @file
+ *
+ * Bit-bashing interfaces
+ *
+ */
+
+/**
+ * Set/clear output bit
+ *
+ * @v basher           Bit-bashing interface
+ * @v bit_id           Bit number
+ * @v data             Value to write
+ * 
+ * If @c data is 0, a logic 0 will be written.  If @c data is
+ * non-zero, a logic 1 will be written.
+ */
+void write_bit ( struct bit_basher *basher, unsigned int bit_id,
+                unsigned long data ) {
+       basher->op->write ( basher, bit_id, ( data ? -1UL : 0 ) );
+}
+
+/**
+ * Read input bit
+ *
+ * @v basher           Bit-bashing interface
+ * @v bit_id           Bit number
+ * @ret data           Value read
+ *
+ * @c data will always be either 0 or -1UL.  The idea is that the
+ * caller can simply binary-AND the returned value with whatever mask
+ * it needs to apply.
+ */
+int read_bit ( struct bit_basher *basher, unsigned int bit_id ) {
+       return ( basher->op->read ( basher, bit_id ) ? -1UL : 0 );
+}