From: Vijaya Kumar K <vijaya.ku...@cavium.com>
Add helper API to read MIDR_EL1 registers to fetch
cpu identification information. This helps in
adding errata's and architecture specific features.
This is implemented only for arm architecture.
Signed-off-by: Vijaya Kumar K <vijaya.ku...@cavium.com>
---
include/qemu-common.h | 1 +
util/Makefile.objs | 1 +
util/cpuinfo.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 54 insertions(+)
diff --git a/include/qemu-common.h b/include/qemu-common.h
index 1f2cb94..62ad674 100644
--- a/include/qemu-common.h
+++ b/include/qemu-common.h
@@ -134,4 +134,5 @@ void page_size_init(void);
* returned. */
bool dump_in_progress(void);
+long int qemu_read_cpuid_info(void);
#endif
diff --git a/util/Makefile.objs b/util/Makefile.objs
index 96cb1e0..9d25a72 100644
--- a/util/Makefile.objs
+++ b/util/Makefile.objs
@@ -35,3 +35,4 @@ util-obj-y += log.o
util-obj-y += qdist.o
util-obj-y += qht.o
util-obj-y += range.o
+util-obj-y += cpuinfo.o
diff --git a/util/cpuinfo.c b/util/cpuinfo.c
new file mode 100644
index 0000000..3ba7194
--- /dev/null
+++ b/util/cpuinfo.c
@@ -0,0 +1,52 @@
+/*
+ * Dealing with arm cpu identification information.
+ *
+ * Copyright (C) 2016 Cavium, Inc.
+ *
+ * Authors:
+ * Vijaya Kumar K <vijaya.ku...@cavium.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.1
+ * or later. See the COPYING.LIB file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "qemu/cutils.h"
+
+#if defined(__aarch64__)
+
+long int qemu_read_cpuid_info(void)
+{
+ FILE *fp;
+ char *buf;
+ long int midr = 0;
+#define BUF_SIZE 32
+
+ fp = fopen("/sys/devices/system/cpu/cpu0/regs/identification/midr_el1",
+ "r");
+ if (!fp) {
+ return 0;
+ }
+
+ buf = g_malloc0(BUF_SIZE);
+ if (!buf) {
+ fclose(fp);
+ return 0;
+ }
+
+ if (buf != fgets(buf, BUF_SIZE - 1, fp)) {
+ goto out;
+ }
+
+ if (qemu_strtol(buf, NULL, 0, &midr) < 0) {
+ goto out;
+ }
+
+out:
+ g_free(buf);
+ fclose(fp);
+
+ return midr;
+}
+#endif
--
1.7.9.5
