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-rw-r--r--drivers/char/hw_random/octeon-rng.c147
1 files changed, 147 insertions, 0 deletions
diff --git a/drivers/char/hw_random/octeon-rng.c b/drivers/char/hw_random/octeon-rng.c
new file mode 100644
index 0000000..54b0d9b
--- /dev/null
+++ b/drivers/char/hw_random/octeon-rng.c
@@ -0,0 +1,147 @@
+/*
+ * Hardware Random Number Generator support for Cavium Networks
+ * Octeon processor family.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2009 Cavium Networks
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/hw_random.h>
+#include <linux/io.h>
+
+#include <asm/octeon/octeon.h>
+#include <asm/octeon/cvmx-rnm-defs.h>
+
+struct octeon_rng {
+ struct hwrng ops;
+ void __iomem *control_status;
+ void __iomem *result;
+};
+
+static int octeon_rng_init(struct hwrng *rng)
+{
+ union cvmx_rnm_ctl_status ctl;
+ struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);
+
+ ctl.u64 = 0;
+ ctl.s.ent_en = 1; /* Enable the entropy source. */
+ ctl.s.rng_en = 1; /* Enable the RNG hardware. */
+ cvmx_write_csr((u64)p->control_status, ctl.u64);
+ return 0;
+}
+
+static void octeon_rng_cleanup(struct hwrng *rng)
+{
+ union cvmx_rnm_ctl_status ctl;
+ struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);
+
+ ctl.u64 = 0;
+ /* Disable everything. */
+ cvmx_write_csr((u64)p->control_status, ctl.u64);
+}
+
+static int octeon_rng_data_read(struct hwrng *rng, u32 *data)
+{
+ struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);
+
+ *data = cvmx_read64_uint32((u64)p->result);
+ return sizeof(u32);
+}
+
+static int __devinit octeon_rng_probe(struct platform_device *pdev)
+{
+ struct resource *res_ports;
+ struct resource *res_result;
+ struct octeon_rng *rng;
+ int ret;
+ struct hwrng ops = {
+ .name = "octeon",
+ .init = octeon_rng_init,
+ .cleanup = octeon_rng_cleanup,
+ .data_read = octeon_rng_data_read
+ };
+
+ rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
+ if (!rng)
+ return -ENOMEM;
+
+ res_ports = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res_ports)
+ goto err_ports;
+
+ res_result = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!res_result)
+ goto err_ports;
+
+
+ rng->control_status = devm_ioremap_nocache(&pdev->dev,
+ res_ports->start,
+ sizeof(u64));
+ if (!rng->control_status)
+ goto err_ports;
+
+ rng->result = devm_ioremap_nocache(&pdev->dev,
+ res_result->start,
+ sizeof(u64));
+ if (!rng->result)
+ goto err_r;
+
+ rng->ops = ops;
+
+ dev_set_drvdata(&pdev->dev, &rng->ops);
+ ret = hwrng_register(&rng->ops);
+ if (ret)
+ goto err;
+
+ dev_info(&pdev->dev, "Octeon Random Number Generator\n");
+
+ return 0;
+err:
+ devm_iounmap(&pdev->dev, rng->control_status);
+err_r:
+ devm_iounmap(&pdev->dev, rng->result);
+err_ports:
+ devm_kfree(&pdev->dev, rng);
+ return -ENOENT;
+}
+
+static int __exit octeon_rng_remove(struct platform_device *pdev)
+{
+ struct hwrng *rng = dev_get_drvdata(&pdev->dev);
+
+ hwrng_unregister(rng);
+
+ return 0;
+}
+
+static struct platform_driver octeon_rng_driver = {
+ .driver = {
+ .name = "octeon_rng",
+ .owner = THIS_MODULE,
+ },
+ .probe = octeon_rng_probe,
+ .remove = __exit_p(octeon_rng_remove),
+};
+
+static int __init octeon_rng_mod_init(void)
+{
+ return platform_driver_register(&octeon_rng_driver);
+}
+
+static void __exit octeon_rng_mod_exit(void)
+{
+ platform_driver_unregister(&octeon_rng_driver);
+}
+
+module_init(octeon_rng_mod_init);
+module_exit(octeon_rng_mod_exit);
+
+MODULE_AUTHOR("David Daney");
+MODULE_LICENSE("GPL");
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