target/linux/brcm63xx/patches-3.3/021-hw_random-add-Broadcom-BCM63xx-RNG-driver.patch

   1 From 1cfc5c76c5f48359716bd804daef2f2f7554fb4a Mon Sep 17 00:00:00 2001
   2 From: Florian Fainelli <florian@openwrt.org>
   3 Date: Tue, 31 Jan 2012 15:12:25 +0100
   4 Subject: [PATCH 6/6] hw_random: add Broadcom BCM63xx RNG driver
   5
   6 Signed-off-by: Florian Fainelli <florian@openwrt.org>
   7 Cc: linux-mips@linux-mips.org
   8 Cc: mpm@selenic.com
   9 Cc: herbert@gondor.apana.org.au
  10 Patchwork: https://patchwork.linux-mips.org/patch/3327/
  11 Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
  12 ---
  13  drivers/char/hw_random/Kconfig       |   14 +++
  14  drivers/char/hw_random/Makefile      |    1 +
  15  drivers/char/hw_random/bcm63xx-rng.c |  175 ++++++++++++++++++++++++++++++++++
  16  3 files changed, 190 insertions(+), 0 deletions(-)
  17  create mode 100644 drivers/char/hw_random/bcm63xx-rng.c
  18
  19 --- a/drivers/char/hw_random/Kconfig
  20 +++ b/drivers/char/hw_random/Kconfig
  21 @@ -73,6 +73,20 @@ config HW_RANDOM_ATMEL
  22
  23           If unsure, say Y.
  24
  25 +config HW_RANDOM_BCM63XX
  26 +       tristate "Broadcom BCM63xx Random Number Generator support"
  27 +       depends on HW_RANDOM && BCM63XX
  28 +       default HW_RANDOM
  29 +       ---help---
  30 +         This driver provides kernel-side support for the Random Number
  31 +         Generator hardware found on the Broadcom BCM63xx SoCs.
  32 +
  33 +         To compile this driver as a module, choose M here: the
  34 +         module will be called bcm63xx-rng
  35 +
  36 +         If unusure, say Y.
  37 +
  38 +
  39  config HW_RANDOM_GEODE
  40         tristate "AMD Geode HW Random Number Generator support"
  41         depends on HW_RANDOM && X86_32 && PCI
  42 --- a/drivers/char/hw_random/Makefile
  43 +++ b/drivers/char/hw_random/Makefile
  44 @@ -8,6 +8,7 @@ obj-$(CONFIG_HW_RANDOM_TIMERIOMEM) += ti
  45  obj-$(CONFIG_HW_RANDOM_INTEL) += intel-rng.o
  46  obj-$(CONFIG_HW_RANDOM_AMD) += amd-rng.o
  47  obj-$(CONFIG_HW_RANDOM_ATMEL) += atmel-rng.o
  48 +obj-$(CONFIG_HW_RANDOM_BCM63XX)        += bcm63xx-rng.o
  49  obj-$(CONFIG_HW_RANDOM_GEODE) += geode-rng.o
  50  obj-$(CONFIG_HW_RANDOM_N2RNG) += n2-rng.o
  51  n2-rng-y := n2-drv.o n2-asm.o
  52 --- /dev/null
  53 +++ b/drivers/char/hw_random/bcm63xx-rng.c
  54 @@ -0,0 +1,175 @@
  55 +/*
  56 + * Broadcom BCM63xx Random Number Generator support
  57 + *
  58 + * Copyright (C) 2011, Florian Fainelli <florian@openwrt.org>
  59 + * Copyright (C) 2009, Broadcom Corporation
  60 + *
  61 + */
  62 +#include <linux/module.h>
  63 +#include <linux/slab.h>
  64 +#include <linux/io.h>
  65 +#include <linux/err.h>
  66 +#include <linux/clk.h>
  67 +#include <linux/platform_device.h>
  68 +#include <linux/hw_random.h>
  69 +
  70 +#include <bcm63xx_io.h>
  71 +#include <bcm63xx_regs.h>
  72 +
  73 +struct bcm63xx_rng_priv {
  74 +       struct clk *clk;
  75 +       void __iomem *regs;
  76 +};
  77 +
  78 +#define to_rng_priv(rng)       ((struct bcm63xx_rng_priv *)rng->priv)
  79 +
  80 +static int bcm63xx_rng_init(struct hwrng *rng)
  81 +{
  82 +       struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
  83 +       u32 val;
  84 +
  85 +       val = bcm_readl(priv->regs + RNG_CTRL);
  86 +       val |= RNG_EN;
  87 +       bcm_writel(val, priv->regs + RNG_CTRL);
  88 +
  89 +       return 0;
  90 +}
  91 +
  92 +static void bcm63xx_rng_cleanup(struct hwrng *rng)
  93 +{
  94 +       struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
  95 +       u32 val;
  96 +
  97 +       val = bcm_readl(priv->regs + RNG_CTRL);
  98 +       val &= ~RNG_EN;
  99 +       bcm_writel(val, priv->regs + RNG_CTRL);
 100 +}
 101 +
 102 +static int bcm63xx_rng_data_present(struct hwrng *rng, int wait)
 103 +{
 104 +       struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
 105 +
 106 +       return bcm_readl(priv->regs + RNG_STAT) & RNG_AVAIL_MASK;
 107 +}
 108 +
 109 +static int bcm63xx_rng_data_read(struct hwrng *rng, u32 *data)
 110 +{
 111 +       struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
 112 +
 113 +       *data = bcm_readl(priv->regs + RNG_DATA);
 114 +
 115 +       return 4;
 116 +}
 117 +
 118 +static int __init bcm63xx_rng_probe(struct platform_device *pdev)
 119 +{
 120 +       struct resource *r;
 121 +       struct clk *clk;
 122 +       int ret;
 123 +       struct bcm63xx_rng_priv *priv;
 124 +       struct hwrng *rng;
 125 +
 126 +       r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 127 +       if (!r) {
 128 +               dev_err(&pdev->dev, "no iomem resource\n");
 129 +               ret = -ENXIO;
 130 +               goto out;
 131 +       }
 132 +
 133 +       priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 134 +       if (!priv) {
 135 +               dev_err(&pdev->dev, "no memory for private structure\n");
 136 +               ret = -ENOMEM;
 137 +               goto out;
 138 +       }
 139 +
 140 +       rng = kzalloc(sizeof(*rng), GFP_KERNEL);
 141 +       if (!rng) {
 142 +               dev_err(&pdev->dev, "no memory for rng structure\n");
 143 +               ret = -ENOMEM;
 144 +               goto out_free_priv;
 145 +       }
 146 +
 147 +       platform_set_drvdata(pdev, rng);
 148 +       rng->priv = (unsigned long)priv;
 149 +       rng->name = pdev->name;
 150 +       rng->init = bcm63xx_rng_init;
 151 +       rng->cleanup = bcm63xx_rng_cleanup;
 152 +       rng->data_present = bcm63xx_rng_data_present;
 153 +       rng->data_read = bcm63xx_rng_data_read;
 154 +
 155 +       clk = clk_get(&pdev->dev, "ipsec");
 156 +       if (IS_ERR(clk)) {
 157 +               dev_err(&pdev->dev, "no clock for device\n");
 158 +               ret = PTR_ERR(clk);
 159 +               goto out_free_rng;
 160 +       }
 161 +
 162 +       priv->clk = clk;
 163 +
 164 +       if (!devm_request_mem_region(&pdev->dev, r->start,
 165 +                                       resource_size(r), pdev->name)) {
 166 +               dev_err(&pdev->dev, "request mem failed");
 167 +               ret = -ENOMEM;
 168 +               goto out_free_rng;
 169 +       }
 170 +
 171 +       priv->regs = devm_ioremap_nocache(&pdev->dev, r->start,
 172 +                                       resource_size(r));
 173 +       if (!priv->regs) {
 174 +               dev_err(&pdev->dev, "ioremap failed");
 175 +               ret = -ENOMEM;
 176 +               goto out_free_rng;
 177 +       }
 178 +
 179 +       clk_enable(clk);
 180 +
 181 +       ret = hwrng_register(rng);
 182 +       if (ret) {
 183 +               dev_err(&pdev->dev, "failed to register rng device\n");
 184 +               goto out_clk_disable;
 185 +       }
 186 +
 187 +       dev_info(&pdev->dev, "registered RNG driver\n");
 188 +
 189 +       return 0;
 190 +
 191 +out_clk_disable:
 192 +       clk_disable(clk);
 193 +out_free_rng:
 194 +       platform_set_drvdata(pdev, NULL);
 195 +       kfree(rng);
 196 +out_free_priv:
 197 +       kfree(priv);
 198 +out:
 199 +       return ret;
 200 +}
 201 +
 202 +static int __devexit bcm63xx_rng_remove(struct platform_device *pdev)
 203 +{
 204 +       struct hwrng *rng = platform_get_drvdata(pdev);
 205 +       struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
 206 +
 207 +       hwrng_unregister(rng);
 208 +       clk_disable(priv->clk);
 209 +       kfree(priv);
 210 +       kfree(rng);
 211 +       platform_set_drvdata(pdev, NULL);
 212 +
 213 +       return 0;
 214 +}
 215 +
 216 +static struct platform_driver bcm63xx_rng_driver = {
 217 +       .probe          = bcm63xx_rng_probe,
 218 +       .remove         = __devexit_p(bcm63xx_rng_remove),
 219 +       .driver         = {
 220 +               .name   = "bcm63xx-rng",
 221 +               .owner  = THIS_MODULE,
 222 +       },
 223 +};
 224 +
 225 +module_platform_driver(bcm63xx_rng_driver);
 226 +
 227 +MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
 228 +MODULE_DESCRIPTION("Broadcom BCM63xx RNG driver");
 229 +MODULE_LICENSE("GPL");