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Diffstat (limited to 'drivers/char/hw_random/msm-rng.c')
-rw-r--r--drivers/char/hw_random/msm-rng.c183
1 files changed, 0 insertions, 183 deletions
diff --git a/drivers/char/hw_random/msm-rng.c b/drivers/char/hw_random/msm-rng.c
deleted file mode 100644
index 841fee845ec9..000000000000
--- a/drivers/char/hw_random/msm-rng.c
+++ /dev/null
@@ -1,183 +0,0 @@
-/*
- * Copyright (c) 2011-2013, The Linux Foundation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 and
- * only version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- */
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/hw_random.h>
-#include <linux/io.h>
-#include <linux/module.h>
-#include <linux/of.h>
-#include <linux/platform_device.h>
-
-/* Device specific register offsets */
-#define PRNG_DATA_OUT 0x0000
-#define PRNG_STATUS 0x0004
-#define PRNG_LFSR_CFG 0x0100
-#define PRNG_CONFIG 0x0104
-
-/* Device specific register masks and config values */
-#define PRNG_LFSR_CFG_MASK 0x0000ffff
-#define PRNG_LFSR_CFG_CLOCKS 0x0000dddd
-#define PRNG_CONFIG_HW_ENABLE BIT(1)
-#define PRNG_STATUS_DATA_AVAIL BIT(0)
-
-#define MAX_HW_FIFO_DEPTH 16
-#define MAX_HW_FIFO_SIZE (MAX_HW_FIFO_DEPTH * 4)
-#define WORD_SZ 4
-
-struct msm_rng {
- void __iomem *base;
- struct clk *clk;
- struct hwrng hwrng;
-};
-
-#define to_msm_rng(p) container_of(p, struct msm_rng, hwrng)
-
-static int msm_rng_enable(struct hwrng *hwrng, int enable)
-{
- struct msm_rng *rng = to_msm_rng(hwrng);
- u32 val;
- int ret;
-
- ret = clk_prepare_enable(rng->clk);
- if (ret)
- return ret;
-
- if (enable) {
- /* Enable PRNG only if it is not already enabled */
- val = readl_relaxed(rng->base + PRNG_CONFIG);
- if (val & PRNG_CONFIG_HW_ENABLE)
- goto already_enabled;
-
- val = readl_relaxed(rng->base + PRNG_LFSR_CFG);
- val &= ~PRNG_LFSR_CFG_MASK;
- val |= PRNG_LFSR_CFG_CLOCKS;
- writel(val, rng->base + PRNG_LFSR_CFG);
-
- val = readl_relaxed(rng->base + PRNG_CONFIG);
- val |= PRNG_CONFIG_HW_ENABLE;
- writel(val, rng->base + PRNG_CONFIG);
- } else {
- val = readl_relaxed(rng->base + PRNG_CONFIG);
- val &= ~PRNG_CONFIG_HW_ENABLE;
- writel(val, rng->base + PRNG_CONFIG);
- }
-
-already_enabled:
- clk_disable_unprepare(rng->clk);
- return 0;
-}
-
-static int msm_rng_read(struct hwrng *hwrng, void *data, size_t max, bool wait)
-{
- struct msm_rng *rng = to_msm_rng(hwrng);
- size_t currsize = 0;
- u32 *retdata = data;
- size_t maxsize;
- int ret;
- u32 val;
-
- /* calculate max size bytes to transfer back to caller */
- maxsize = min_t(size_t, MAX_HW_FIFO_SIZE, max);
-
- ret = clk_prepare_enable(rng->clk);
- if (ret)
- return ret;
-
- /* read random data from hardware */
- do {
- val = readl_relaxed(rng->base + PRNG_STATUS);
- if (!(val & PRNG_STATUS_DATA_AVAIL))
- break;
-
- val = readl_relaxed(rng->base + PRNG_DATA_OUT);
- if (!val)
- break;
-
- *retdata++ = val;
- currsize += WORD_SZ;
-
- /* make sure we stay on 32bit boundary */
- if ((maxsize - currsize) < WORD_SZ)
- break;
- } while (currsize < maxsize);
-
- clk_disable_unprepare(rng->clk);
-
- return currsize;
-}
-
-static int msm_rng_init(struct hwrng *hwrng)
-{
- return msm_rng_enable(hwrng, 1);
-}
-
-static void msm_rng_cleanup(struct hwrng *hwrng)
-{
- msm_rng_enable(hwrng, 0);
-}
-
-static int msm_rng_probe(struct platform_device *pdev)
-{
- struct resource *res;
- struct msm_rng *rng;
- int ret;
-
- rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
- if (!rng)
- return -ENOMEM;
-
- platform_set_drvdata(pdev, rng);
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- rng->base = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(rng->base))
- return PTR_ERR(rng->base);
-
- rng->clk = devm_clk_get(&pdev->dev, "core");
- if (IS_ERR(rng->clk))
- return PTR_ERR(rng->clk);
-
- rng->hwrng.name = KBUILD_MODNAME,
- rng->hwrng.init = msm_rng_init,
- rng->hwrng.cleanup = msm_rng_cleanup,
- rng->hwrng.read = msm_rng_read,
-
- ret = devm_hwrng_register(&pdev->dev, &rng->hwrng);
- if (ret) {
- dev_err(&pdev->dev, "failed to register hwrng\n");
- return ret;
- }
-
- return 0;
-}
-
-static const struct of_device_id msm_rng_of_match[] = {
- { .compatible = "qcom,prng", },
- {}
-};
-MODULE_DEVICE_TABLE(of, msm_rng_of_match);
-
-static struct platform_driver msm_rng_driver = {
- .probe = msm_rng_probe,
- .driver = {
- .name = KBUILD_MODNAME,
- .of_match_table = of_match_ptr(msm_rng_of_match),
- }
-};
-module_platform_driver(msm_rng_driver);
-
-MODULE_ALIAS("platform:" KBUILD_MODNAME);
-MODULE_AUTHOR("The Linux Foundation");
-MODULE_DESCRIPTION("Qualcomm MSM random number generator driver");
-MODULE_LICENSE("GPL v2");