1 files changed, 76 insertions, 0 deletions
diff --git a/drivers/char/hw_random/ixp4xx-rng.c b/drivers/char/hw_random/ixp4xx-rng.c
new file mode 100644
index 0000000000..7df5e9f751
--- /dev/null
+++ b/drivers/char/hw_random/ixp4xx-rng.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * drivers/char/hw_random/ixp4xx-rng.c
+ *
+ * RNG driver for Intel IXP4xx family of NPUs
+ *
+ * Author: Deepak Saxena <dsaxena@plexity.net>
+ *
+ * Copyright 2005 (c) MontaVista Software, Inc.
+ *
+ * Fixes by Michael Buesch
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/hw_random.h>
+#include <linux/of.h>
+#include <linux/soc/ixp4xx/cpu.h>
+
+#include <asm/io.h>
+
+static int ixp4xx_rng_data_read(struct hwrng *rng, u32 *buffer)
+{
+	void __iomem * rng_base = (void __iomem *)rng->priv;
+
+	*buffer = __raw_readl(rng_base);
+
+	return 4;
+}
+
+static struct hwrng ixp4xx_rng_ops = {
+	.name		= "ixp4xx",
+	.data_read	= ixp4xx_rng_data_read,
+};
+
+static int ixp4xx_rng_probe(struct platform_device *pdev)
+{
+	void __iomem * rng_base;
+	struct device *dev = &pdev->dev;
+
+	if (!cpu_is_ixp46x()) /* includes IXP455 */
+		return -ENOSYS;
+
+	rng_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(rng_base))
+		return PTR_ERR(rng_base);
+
+	ixp4xx_rng_ops.priv = (unsigned long)rng_base;
+	return devm_hwrng_register(dev, &ixp4xx_rng_ops);
+}
+
+static const struct of_device_id ixp4xx_rng_of_match[] = {
+	{
+		.compatible = "intel,ixp46x-rng",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, ixp4xx_rng_of_match);
+
+static struct platform_driver ixp4xx_rng_driver = {
+	.driver = {
+		.name = "ixp4xx-hwrandom",
+		.of_match_table = ixp4xx_rng_of_match,
+	},
+	.probe = ixp4xx_rng_probe,
+};
+module_platform_driver(ixp4xx_rng_driver);
+
+MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
+MODULE_DESCRIPTION("H/W Pseudo-Random Number Generator (RNG) driver for IXP45x/46x");
+MODULE_LICENSE("GPL");