eal: split CPU flags operations to architecture specific

[dpdk.git] / lib / librte_eal / common / include / generic / rte_cpuflags.h

diff --git a/lib/librte_eal/common/include/generic/rte_cpuflags.h b/lib/librte_eal/common/include/generic/rte_cpuflags.h
new file mode 100644 (file)
index 0000000..7f04838
--- /dev/null
+++ b/lib/librte_eal/common/include/generic/rte_cpuflags.h
@@ -0,0 +1,110 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _RTE_CPUFLAGS_H_
+#define _RTE_CPUFLAGS_H_
+
+/**
+ * @file
+ * Architecture specific API to determine available CPU features at runtime.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdint.h>
+
+/**
+ * Enumeration of all CPU features supported
+ */
+enum rte_cpu_flag_t;
+
+/**
+ * Enumeration of CPU registers
+ */
+enum cpu_register_t;
+
+typedef uint32_t cpuid_registers_t[4];
+
+#define CPU_FLAG_NAME_MAX_LEN 64
+
+/**
+ * Struct to hold a processor feature entry
+ */
+struct feature_entry {
+       uint32_t leaf;                          /**< cpuid leaf */
+       uint32_t subleaf;                       /**< cpuid subleaf */
+       uint32_t reg;                           /**< cpuid register */
+       uint32_t bit;                           /**< cpuid register bit */
+       char name[CPU_FLAG_NAME_MAX_LEN];       /**< String for printing */
+};
+
+#define FEAT_DEF(name, leaf, subleaf, reg, bit) \
+       [RTE_CPUFLAG_##name] = {leaf, subleaf, reg, bit, #name },
+
+/**
+ * An array that holds feature entries
+ */
+static const struct feature_entry cpu_feature_table[];
+
+/**
+ * Execute CPUID instruction and get contents of a specific register
+ *
+ * This function, when compiled with GCC, will generate architecture-neutral
+ * code, as per GCC manual.
+ */
+static inline void
+rte_cpu_get_features(uint32_t leaf, uint32_t subleaf, cpuid_registers_t out);
+
+/**
+ * Function for checking a CPU flag availability
+ *
+ * @param flag
+ *     CPU flag to query CPU for
+ * @return
+ *     1 if flag is available
+ *     0 if flag is not available
+ *     -ENOENT if flag is invalid
+ */
+static inline int
+rte_cpu_get_flag_enabled(enum rte_cpu_flag_t feature);
+
+/**
+ * This function checks that the currently used CPU supports the CPU features
+ * that were specified at compile time. It is called automatically within the
+ * EAL, so does not need to be used by applications.
+ */
+void
+rte_cpu_check_supported(void);
+
+#endif /* _RTE_CPUFLAGS_H_ */