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@@ -0,0 +1,120 @@
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+// SPDX-License-Identifier: GPL-2.0-or-later
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+/*
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+ * Copyright 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
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+ *
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+ * Driver for Amlogic hardware random number generator
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+ */
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+
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+#include <common.h>
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+#include <clk.h>
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+#include <dm.h>
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+#include <rng.h>
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+#include <asm/io.h>
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+
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+struct meson_rng_platdata {
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+ fdt_addr_t base;
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+ struct clk clk;
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+};
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+
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+/**
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+ * meson_rng_read() - fill buffer with random bytes
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+ *
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+ * @buffer: buffer to receive data
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+ * @size: size of buffer
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+ *
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+ * Return: 0
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+ */
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+static int meson_rng_read(struct udevice *dev, void *data, size_t len)
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+{
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+ struct meson_rng_platdata *pdata = dev_get_platdata(dev);
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+ char *buffer = (char *)data;
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+
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+ while (len) {
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+ u32 rand = readl(pdata->base);
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+ size_t step;
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+
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+ if (len >= 4)
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+ step = 4;
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+ else
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+ step = len;
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+ memcpy(buffer, &rand, step);
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+ buffer += step;
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+ len -= step;
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+ }
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+ return 0;
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+}
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+
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+/**
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+ * meson_rng_probe() - probe rng device
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+ *
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+ * @dev: device
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+ * Return: 0 if ok
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+ */
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+static int meson_rng_probe(struct udevice *dev)
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+{
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+ struct meson_rng_platdata *pdata = dev_get_platdata(dev);
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+ int err;
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+
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+ err = clk_enable(&pdata->clk);
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+ if (err)
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+ return err;
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+
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+ return 0;
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+}
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+
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+/**
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+ * meson_rng_remove() - deinitialize rng device
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+ *
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+ * @dev: device
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+ * Return: 0 if ok
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+ */
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+static int meson_rng_remove(struct udevice *dev)
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+{
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+ struct meson_rng_platdata *pdata = dev_get_platdata(dev);
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+
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+ return clk_disable(&pdata->clk);
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+}
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+
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+/**
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+ * meson_rng_ofdata_to_platdata() - transfer device tree data to plaform data
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+ *
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+ * @dev: device
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+ * Return: 0 if ok
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+ */
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+static int meson_rng_ofdata_to_platdata(struct udevice *dev)
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+{
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+ struct meson_rng_platdata *pdata = dev_get_platdata(dev);
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+ int err;
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+
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+ pdata->base = dev_read_addr(dev);
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+ if (!pdata->base)
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+ return -ENODEV;
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+
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+ err = clk_get_by_name(dev, "core", &pdata->clk);
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+ if (err)
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+ return err;
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+
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+ return 0;
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+}
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+
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+static const struct dm_rng_ops meson_rng_ops = {
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+ .read = meson_rng_read,
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+};
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+
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+static const struct udevice_id meson_rng_match[] = {
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+ {
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+ .compatible = "amlogic,meson-rng",
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+ },
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+ {},
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+};
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+
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+U_BOOT_DRIVER(meson_rng) = {
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+ .name = "meson-rng",
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+ .id = UCLASS_RNG,
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+ .of_match = meson_rng_match,
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+ .ops = &meson_rng_ops,
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+ .probe = meson_rng_probe,
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+ .remove = meson_rng_remove,
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+ .platdata_auto_alloc_size = sizeof(struct meson_rng_platdata),
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+ .ofdata_to_platdata = meson_rng_ofdata_to_platdata,
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+};
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