target/linux/brcm63xx/patches-3.3/105-hw_random-add-Broadcom-BCM63xx-RNG-driver.patch

   1 From 21a474b37f905387d8908384a24c13d4f8513113 Mon Sep 17 00:00:00 2001
   2 From: Florian Fainelli <florian@openwrt.org>
   3 Date: Wed, 25 Jan 2012 17:40:02 +0100
   4 Subject: [PATCH 18/63] hw_random: add Broadcom BCM63xx RNG driver
   5
   6 Signed-off-by: Florian Fainelli <florian@openwrt.org>
   7 ---
   8  drivers/char/hw_random/Kconfig       |   14 +++
   9  drivers/char/hw_random/Makefile      |    1 +
  10  drivers/char/hw_random/bcm63xx-rng.c |  175 ++++++++++++++++++++++++++++++++++
  11  3 files changed, 190 insertions(+), 0 deletions(-)
  12  create mode 100644 drivers/char/hw_random/bcm63xx-rng.c
  13
  14 --- a/drivers/char/hw_random/Kconfig
  15 +++ b/drivers/char/hw_random/Kconfig
  16 @@ -73,6 +73,20 @@ config HW_RANDOM_ATMEL
  17
  18           If unsure, say Y.
  19
  20 +config HW_RANDOM_BCM63XX
  21 +       tristate "Broadcom BCM63xx Random Number Generator support"
  22 +       depends on HW_RANDOM && BCM63XX
  23 +       default HW_RANDOM
  24 +       ---help---
  25 +         This driver provides kernel-side support for the Random Number
  26 +         Generator hardware found on the Broadcom BCM63xx SoCs.
  27 +
  28 +         To compile this driver as a module, choose M here: the
  29 +         module will be called bcm63xx-rng
  30 +
  31 +         If unusure, say Y.
  32 +
  33 +
  34  config HW_RANDOM_GEODE
  35         tristate "AMD Geode HW Random Number Generator support"
  36         depends on HW_RANDOM && X86_32 && PCI
  37 --- a/drivers/char/hw_random/Makefile
  38 +++ b/drivers/char/hw_random/Makefile
  39 @@ -8,6 +8,7 @@ obj-$(CONFIG_HW_RANDOM_TIMERIOMEM) += ti
  40  obj-$(CONFIG_HW_RANDOM_INTEL) += intel-rng.o
  41  obj-$(CONFIG_HW_RANDOM_AMD) += amd-rng.o
  42  obj-$(CONFIG_HW_RANDOM_ATMEL) += atmel-rng.o
  43 +obj-$(CONFIG_HW_RANDOM_BCM63XX)        += bcm63xx-rng.o
  44  obj-$(CONFIG_HW_RANDOM_GEODE) += geode-rng.o
  45  obj-$(CONFIG_HW_RANDOM_N2RNG) += n2-rng.o
  46  n2-rng-y := n2-drv.o n2-asm.o
  47 --- /dev/null
  48 +++ b/drivers/char/hw_random/bcm63xx-rng.c
  49 @@ -0,0 +1,175 @@
  50 +/*
  51 + * Broadcom BCM63xx Random Number Generator support
  52 + *
  53 + * Copyright (C) 2011, Florian Fainelli <florian@openwrt.org>
  54 + * Copyright (C) 2009, Broadcom Corporation
  55 + *
  56 + */
  57 +#include <linux/module.h>
  58 +#include <linux/slab.h>
  59 +#include <linux/io.h>
  60 +#include <linux/err.h>
  61 +#include <linux/clk.h>
  62 +#include <linux/platform_device.h>
  63 +#include <linux/hw_random.h>
  64 +
  65 +#include <bcm63xx_io.h>
  66 +#include <bcm63xx_regs.h>
  67 +
  68 +struct bcm63xx_trng_priv {
  69 +       struct clk *clk;
  70 +       void __iomem *regs;
  71 +};
  72 +
  73 +#define to_trng_priv(rng)      ((struct bcm63xx_trng_priv *)rng->priv)
  74 +
  75 +static int bcm63xx_trng_init(struct hwrng *rng)
  76 +{
  77 +       struct bcm63xx_trng_priv *priv = to_trng_priv(rng);
  78 +       u32 val;
  79 +
  80 +       val = bcm_readl(priv->regs + TRNG_CTRL);
  81 +       val |= TRNG_EN;
  82 +       bcm_writel(val, priv->regs + TRNG_CTRL);
  83 +
  84 +       return 0;
  85 +}
  86 +
  87 +static void bcm63xx_trng_cleanup(struct hwrng *rng)
  88 +{
  89 +       struct bcm63xx_trng_priv *priv = to_trng_priv(rng);
  90 +       u32 val;
  91 +
  92 +       val = bcm_readl(priv->regs + TRNG_CTRL);
  93 +       val &= ~TRNG_EN;
  94 +       bcm_writel(val, priv->regs + TRNG_CTRL);
  95 +}
  96 +
  97 +static int bcm63xx_trng_data_present(struct hwrng *rng, int wait)
  98 +{
  99 +       struct bcm63xx_trng_priv *priv = to_trng_priv(rng);
 100 +
 101 +       return bcm_readl(priv->regs + TRNG_STAT) & TRNG_AVAIL_MASK;
 102 +}
 103 +
 104 +static int bcm63xx_trng_data_read(struct hwrng *rng, u32 *data)
 105 +{
 106 +       struct bcm63xx_trng_priv *priv = to_trng_priv(rng);
 107 +
 108 +       *data = bcm_readl(priv->regs + TRNG_DATA);
 109 +
 110 +       return 4;
 111 +}
 112 +
 113 +static int __devinit bcm63xx_trng_probe(struct platform_device *pdev)
 114 +{
 115 +       struct resource *r;
 116 +       struct clk *clk;
 117 +       int ret;
 118 +       struct bcm63xx_trng_priv *priv;
 119 +       struct hwrng *rng;
 120 +
 121 +       r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 122 +       if (!r) {
 123 +               dev_err(&pdev->dev, "no iomem resource\n");
 124 +               ret = -ENXIO;
 125 +               goto out;
 126 +       }
 127 +
 128 +       priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 129 +       if (!priv) {
 130 +               dev_err(&pdev->dev, "no memory for private structure\n");
 131 +               ret = -ENOMEM;
 132 +               goto out;
 133 +       }
 134 +
 135 +       rng = kzalloc(sizeof(*rng), GFP_KERNEL);
 136 +       if (!rng) {
 137 +               dev_err(&pdev->dev, "no memory for rng structure\n");
 138 +               ret = -ENOMEM;
 139 +               goto out_free_priv;
 140 +       }
 141 +
 142 +       platform_set_drvdata(pdev, rng);
 143 +       rng->priv = (unsigned long)priv;
 144 +       rng->name = pdev->name;
 145 +       rng->init = bcm63xx_trng_init;
 146 +       rng->cleanup = bcm63xx_trng_cleanup;
 147 +       rng->data_present = bcm63xx_trng_data_present;
 148 +       rng->data_read = bcm63xx_trng_data_read;
 149 +
 150 +       clk = clk_get(&pdev->dev, "ipsec");
 151 +       if (IS_ERR(clk)) {
 152 +               dev_err(&pdev->dev, "no clock for device\n");
 153 +               ret = PTR_ERR(clk);
 154 +               goto out_free_rng;
 155 +       }
 156 +
 157 +       priv->clk = clk;
 158 +
 159 +       if (!devm_request_mem_region(&pdev->dev, r->start,
 160 +                                       resource_size(r), pdev->name)) {
 161 +               dev_err(&pdev->dev, "request mem failed");
 162 +               ret = -ENOMEM;
 163 +               goto out_free_rng;
 164 +       }
 165 +
 166 +       priv->regs = devm_ioremap_nocache(&pdev->dev, r->start,
 167 +                                       resource_size(r));
 168 +       if (!priv->regs) {
 169 +               dev_err(&pdev->dev, "ioremap failed");
 170 +               ret = -ENOMEM;
 171 +               goto out_free_rng;
 172 +       }
 173 +
 174 +       clk_enable(clk);
 175 +
 176 +       ret = hwrng_register(rng);
 177 +       if (ret) {
 178 +               dev_err(&pdev->dev, "failed to register rng device\n");
 179 +               goto out_clk_disable;
 180 +       }
 181 +
 182 +       dev_info(&pdev->dev, "registered RNG driver\n");
 183 +
 184 +       return 0;
 185 +
 186 +out_clk_disable:
 187 +       clk_disable(clk);
 188 +out_free_rng:
 189 +       platform_set_drvdata(pdev, NULL);
 190 +       kfree(rng);
 191 +out_free_priv:
 192 +       kfree(priv);
 193 +out:
 194 +       return ret;
 195 +}
 196 +
 197 +static int __devexit bcm63xx_trng_remove(struct platform_device *pdev)
 198 +{
 199 +       struct hwrng *rng = platform_get_drvdata(pdev);
 200 +       struct bcm63xx_trng_priv *priv = to_trng_priv(rng);
 201 +
 202 +       hwrng_unregister(rng);
 203 +       clk_disable(priv->clk);
 204 +       kfree(priv);
 205 +       kfree(rng);
 206 +       platform_set_drvdata(pdev, NULL);
 207 +
 208 +       return 0;
 209 +}
 210 +
 211 +static struct platform_driver bcm63xx_trng_driver = {
 212 +       .probe          = bcm63xx_trng_probe,
 213 +       .remove         = __devexit_p(bcm63xx_trng_remove),
 214 +       .driver         = {
 215 +               .name   = "bcm63xx-trng",
 216 +               .owner  = THIS_MODULE,
 217 +       },
 218 +};
 219 +
 220 +module_platform_driver(bcm63xx_trng_driver);
 221 +
 222 +MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
 223 +MODULE_DESCRIPTION("Broadcom BCM63xx RNG driver");
 224 +MODULE_LICENSE("GPL");