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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/geode-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/geode-rng.c')
-rw-r--r--kernel/drivers/char/hw_random/geode-rng.c139
1 files changed, 139 insertions, 0 deletions
diff --git a/kernel/drivers/char/hw_random/geode-rng.c b/kernel/drivers/char/hw_random/geode-rng.c
new file mode 100644
index 000000000..0d0579fe4
--- /dev/null
+++ b/kernel/drivers/char/hw_random/geode-rng.c
@@ -0,0 +1,139 @@
+/*
+ * RNG driver for AMD Geode RNGs
+ *
+ * Copyright 2005 (c) MontaVista Software, Inc.
+ *
+ * with the majority of the code coming from:
+ *
+ * Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG)
+ * (c) Copyright 2003 Red Hat Inc <jgarzik@redhat.com>
+ *
+ * derived from
+ *
+ * Hardware driver for the AMD 768 Random Number Generator (RNG)
+ * (c) Copyright 2001 Red Hat Inc
+ *
+ * derived from
+ *
+ * Hardware driver for Intel i810 Random Number Generator (RNG)
+ * Copyright 2000,2001 Jeff Garzik <jgarzik@pobox.com>
+ * Copyright 2000,2001 Philipp Rumpf <prumpf@mandrakesoft.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/hw_random.h>
+#include <linux/delay.h>
+#include <asm/io.h>
+
+
+#define PFX KBUILD_MODNAME ": "
+
+#define GEODE_RNG_DATA_REG 0x50
+#define GEODE_RNG_STATUS_REG 0x54
+
+/*
+ * Data for PCI driver interface
+ *
+ * This data only exists for exporting the supported
+ * PCI ids via MODULE_DEVICE_TABLE. We do not actually
+ * register a pci_driver, because someone else might one day
+ * want to register another driver on the same PCI id.
+ */
+static const struct pci_device_id pci_tbl[] = {
+ { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_LX_AES), 0, },
+ { 0, }, /* terminate list */
+};
+MODULE_DEVICE_TABLE(pci, pci_tbl);
+
+
+static int geode_rng_data_read(struct hwrng *rng, u32 *data)
+{
+ void __iomem *mem = (void __iomem *)rng->priv;
+
+ *data = readl(mem + GEODE_RNG_DATA_REG);
+
+ return 4;
+}
+
+static int geode_rng_data_present(struct hwrng *rng, int wait)
+{
+ void __iomem *mem = (void __iomem *)rng->priv;
+ int data, i;
+
+ for (i = 0; i < 20; i++) {
+ data = !!(readl(mem + GEODE_RNG_STATUS_REG));
+ if (data || !wait)
+ break;
+ udelay(10);
+ }
+ return data;
+}
+
+
+static struct hwrng geode_rng = {
+ .name = "geode",
+ .data_present = geode_rng_data_present,
+ .data_read = geode_rng_data_read,
+};
+
+
+static int __init mod_init(void)
+{
+ int err = -ENODEV;
+ struct pci_dev *pdev = NULL;
+ const struct pci_device_id *ent;
+ void __iomem *mem;
+ unsigned long rng_base;
+
+ for_each_pci_dev(pdev) {
+ ent = pci_match_id(pci_tbl, pdev);
+ if (ent)
+ goto found;
+ }
+ /* Device not found. */
+ goto out;
+
+found:
+ rng_base = pci_resource_start(pdev, 0);
+ if (rng_base == 0)
+ goto out;
+ err = -ENOMEM;
+ mem = ioremap(rng_base, 0x58);
+ if (!mem)
+ goto out;
+ geode_rng.priv = (unsigned long)mem;
+
+ pr_info("AMD Geode RNG detected\n");
+ err = hwrng_register(&geode_rng);
+ if (err) {
+ pr_err(PFX "RNG registering failed (%d)\n",
+ err);
+ goto err_unmap;
+ }
+out:
+ return err;
+
+err_unmap:
+ iounmap(mem);
+ goto out;
+}
+
+static void __exit mod_exit(void)
+{
+ void __iomem *mem = (void __iomem *)geode_rng.priv;
+
+ hwrng_unregister(&geode_rng);
+ iounmap(mem);
+}
+
+module_init(mod_init);
+module_exit(mod_exit);
+
+MODULE_DESCRIPTION("H/W RNG driver for AMD Geode LX CPUs");
+MODULE_LICENSE("GPL");