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@@ -1,183 +0,0 @@
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-/*
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- * Copyright (c) 2011-2013, The Linux Foundation. All rights reserved.
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- *
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- * This program is free software; you can redistribute it and/or modify
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- * it under the terms of the GNU General Public License version 2 and
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- * only version 2 as published by the Free Software Foundation.
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- *
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- * This program is distributed in the hope that it will be useful,
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- * but WITHOUT ANY WARRANTY; without even the implied warranty of
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- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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- * GNU General Public License for more details.
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- *
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- */
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-#include <linux/clk.h>
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-#include <linux/err.h>
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-#include <linux/hw_random.h>
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-#include <linux/io.h>
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-#include <linux/module.h>
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-#include <linux/of.h>
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-#include <linux/platform_device.h>
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-
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-/* Device specific register offsets */
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-#define PRNG_DATA_OUT 0x0000
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-#define PRNG_STATUS 0x0004
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-#define PRNG_LFSR_CFG 0x0100
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-#define PRNG_CONFIG 0x0104
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-
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-/* Device specific register masks and config values */
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-#define PRNG_LFSR_CFG_MASK 0x0000ffff
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-#define PRNG_LFSR_CFG_CLOCKS 0x0000dddd
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-#define PRNG_CONFIG_HW_ENABLE BIT(1)
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-#define PRNG_STATUS_DATA_AVAIL BIT(0)
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-
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-#define MAX_HW_FIFO_DEPTH 16
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-#define MAX_HW_FIFO_SIZE (MAX_HW_FIFO_DEPTH * 4)
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-#define WORD_SZ 4
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-
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-struct msm_rng {
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- void __iomem *base;
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- struct clk *clk;
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- struct hwrng hwrng;
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-};
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-
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-#define to_msm_rng(p) container_of(p, struct msm_rng, hwrng)
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-
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-static int msm_rng_enable(struct hwrng *hwrng, int enable)
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-{
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- struct msm_rng *rng = to_msm_rng(hwrng);
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- u32 val;
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- int ret;
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-
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- ret = clk_prepare_enable(rng->clk);
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- if (ret)
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- return ret;
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-
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- if (enable) {
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- /* Enable PRNG only if it is not already enabled */
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- val = readl_relaxed(rng->base + PRNG_CONFIG);
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- if (val & PRNG_CONFIG_HW_ENABLE)
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- goto already_enabled;
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-
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- val = readl_relaxed(rng->base + PRNG_LFSR_CFG);
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- val &= ~PRNG_LFSR_CFG_MASK;
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- val |= PRNG_LFSR_CFG_CLOCKS;
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- writel(val, rng->base + PRNG_LFSR_CFG);
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-
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- val = readl_relaxed(rng->base + PRNG_CONFIG);
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- val |= PRNG_CONFIG_HW_ENABLE;
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- writel(val, rng->base + PRNG_CONFIG);
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- } else {
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- val = readl_relaxed(rng->base + PRNG_CONFIG);
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- val &= ~PRNG_CONFIG_HW_ENABLE;
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- writel(val, rng->base + PRNG_CONFIG);
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- }
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-
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-already_enabled:
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- clk_disable_unprepare(rng->clk);
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- return 0;
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-}
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-
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-static int msm_rng_read(struct hwrng *hwrng, void *data, size_t max, bool wait)
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-{
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- struct msm_rng *rng = to_msm_rng(hwrng);
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- size_t currsize = 0;
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- u32 *retdata = data;
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- size_t maxsize;
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- int ret;
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- u32 val;
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-
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- /* calculate max size bytes to transfer back to caller */
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- maxsize = min_t(size_t, MAX_HW_FIFO_SIZE, max);
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-
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- ret = clk_prepare_enable(rng->clk);
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- if (ret)
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- return ret;
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-
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- /* read random data from hardware */
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- do {
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- val = readl_relaxed(rng->base + PRNG_STATUS);
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- if (!(val & PRNG_STATUS_DATA_AVAIL))
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- break;
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-
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- val = readl_relaxed(rng->base + PRNG_DATA_OUT);
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- if (!val)
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- break;
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-
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- *retdata++ = val;
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- currsize += WORD_SZ;
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-
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- /* make sure we stay on 32bit boundary */
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- if ((maxsize - currsize) < WORD_SZ)
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- break;
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- } while (currsize < maxsize);
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-
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- clk_disable_unprepare(rng->clk);
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-
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- return currsize;
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-}
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-
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-static int msm_rng_init(struct hwrng *hwrng)
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-{
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- return msm_rng_enable(hwrng, 1);
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-}
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-
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-static void msm_rng_cleanup(struct hwrng *hwrng)
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-{
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- msm_rng_enable(hwrng, 0);
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-}
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-
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-static int msm_rng_probe(struct platform_device *pdev)
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-{
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- struct resource *res;
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- struct msm_rng *rng;
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- int ret;
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-
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- rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
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- if (!rng)
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- return -ENOMEM;
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-
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- platform_set_drvdata(pdev, rng);
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-
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- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
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- rng->base = devm_ioremap_resource(&pdev->dev, res);
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- if (IS_ERR(rng->base))
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- return PTR_ERR(rng->base);
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-
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- rng->clk = devm_clk_get(&pdev->dev, "core");
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- if (IS_ERR(rng->clk))
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- return PTR_ERR(rng->clk);
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-
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- rng->hwrng.name = KBUILD_MODNAME,
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- rng->hwrng.init = msm_rng_init,
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- rng->hwrng.cleanup = msm_rng_cleanup,
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- rng->hwrng.read = msm_rng_read,
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-
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- ret = devm_hwrng_register(&pdev->dev, &rng->hwrng);
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- if (ret) {
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- dev_err(&pdev->dev, "failed to register hwrng\n");
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- return ret;
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- }
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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 of_device_id msm_rng_of_match[] = {
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- { .compatible = "qcom,prng", },
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- {}
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-};
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-MODULE_DEVICE_TABLE(of, msm_rng_of_match);
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-
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-static struct platform_driver msm_rng_driver = {
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- .probe = msm_rng_probe,
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- .driver = {
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- .name = KBUILD_MODNAME,
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- .of_match_table = of_match_ptr(msm_rng_of_match),
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- }
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-};
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-module_platform_driver(msm_rng_driver);
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-
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-MODULE_ALIAS("platform:" KBUILD_MODNAME);
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-MODULE_AUTHOR("The Linux Foundation");
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-MODULE_DESCRIPTION("Qualcomm MSM random number generator driver");
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-MODULE_LICENSE("GPL v2");
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