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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/char/hw_random/pseries-rng.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/char/hw_random/pseries-rng.c')
-rw-r--r--kernel/drivers/char/hw_random/pseries-rng.c106
1 files changed, 106 insertions, 0 deletions
diff --git a/kernel/drivers/char/hw_random/pseries-rng.c b/kernel/drivers/char/hw_random/pseries-rng.c
new file mode 100644
index 000000000..63ce51d09
--- /dev/null
+++ b/kernel/drivers/char/hw_random/pseries-rng.c
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2010 Michael Neuling IBM Corporation
+ *
+ * Driver for the pseries hardware RNG for POWER7+ and above
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/hw_random.h>
+#include <asm/vio.h>
+
+
+static int pseries_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+ u64 buffer[PLPAR_HCALL_BUFSIZE];
+ size_t size = max < 8 ? max : 8;
+ int rc;
+
+ rc = plpar_hcall(H_RANDOM, (unsigned long *)buffer);
+ if (rc != H_SUCCESS) {
+ pr_err_ratelimited("H_RANDOM call failed %d\n", rc);
+ return -EIO;
+ }
+ memcpy(data, buffer, size);
+
+ /* The hypervisor interface returns 64 bits */
+ return size;
+}
+
+/**
+ * pseries_rng_get_desired_dma - Return desired DMA allocate for CMO operations
+ *
+ * This is a required function for a driver to operate in a CMO environment
+ * but this device does not make use of DMA allocations, return 0.
+ *
+ * Return value:
+ * Number of bytes of IO data the driver will need to perform well -> 0
+ */
+static unsigned long pseries_rng_get_desired_dma(struct vio_dev *vdev)
+{
+ return 0;
+};
+
+static struct hwrng pseries_rng = {
+ .name = KBUILD_MODNAME,
+ .read = pseries_rng_read,
+};
+
+static int pseries_rng_probe(struct vio_dev *dev,
+ const struct vio_device_id *id)
+{
+ return hwrng_register(&pseries_rng);
+}
+
+static int pseries_rng_remove(struct vio_dev *dev)
+{
+ hwrng_unregister(&pseries_rng);
+ return 0;
+}
+
+static struct vio_device_id pseries_rng_driver_ids[] = {
+ { "ibm,random-v1", "ibm,random"},
+ { "", "" }
+};
+MODULE_DEVICE_TABLE(vio, pseries_rng_driver_ids);
+
+static struct vio_driver pseries_rng_driver = {
+ .name = KBUILD_MODNAME,
+ .probe = pseries_rng_probe,
+ .remove = pseries_rng_remove,
+ .get_desired_dma = pseries_rng_get_desired_dma,
+ .id_table = pseries_rng_driver_ids
+};
+
+static int __init rng_init(void)
+{
+ pr_info("Registering IBM pSeries RNG driver\n");
+ return vio_register_driver(&pseries_rng_driver);
+}
+
+module_init(rng_init);
+
+static void __exit rng_exit(void)
+{
+ vio_unregister_driver(&pseries_rng_driver);
+}
+module_exit(rng_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Michael Neuling <mikey@neuling.org>");
+MODULE_DESCRIPTION("H/W RNG driver for IBM pSeries processors");