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authorYendapally Reddy Dhananjaya Reddy <yendapally.reddy@broadcom.com>2016-05-27 06:10:39 -0400
committerHerbert Xu <herbert@gondor.apana.org.au>2016-05-31 17:52:23 +0800
commit422a7491459b4d989259cd94fd21f4fbde382930 (patch)
tree573a5550f2e29eff66b489e50e20d63de0da2a0b /drivers/char/hw_random/bcm2835-rng.c
parentf8e4f9a0a85d3589d20c4c9f20e576cc8d3c99b6 (diff)
hwrng: bcm2835 - Support Broadcom NSP SoC rng
This supports the random number generator available in NSP SoC. Masks the rng interrupt for NSP. Signed-off-by: Yendapally Reddy Dhananjaya Reddy <yendapally.reddy@broadcom.com> Acked-by: Eric Anholt <eric@anholt.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/char/hw_random/bcm2835-rng.c')
-rw-r--r--drivers/char/hw_random/bcm2835-rng.c34
1 files changed, 30 insertions, 4 deletions
diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c
index 7192ec25f667..b1e8b7847e9a 100644
--- a/drivers/char/hw_random/bcm2835-rng.c
+++ b/drivers/char/hw_random/bcm2835-rng.c
@@ -19,6 +19,7 @@
#define RNG_CTRL 0x0
#define RNG_STATUS 0x4
#define RNG_DATA 0x8
+#define RNG_INT_MASK 0x10
/* enable rng */
#define RNG_RBGEN 0x1
@@ -26,6 +27,18 @@
/* the initial numbers generated are "less random" so will be discarded */
#define RNG_WARMUP_COUNT 0x40000
+#define RNG_INT_OFF 0x1
+
+static void __init nsp_rng_init(void __iomem *base)
+{
+ u32 val;
+
+ /* mask the interrupt */
+ val = readl(base + RNG_INT_MASK);
+ val |= RNG_INT_OFF;
+ writel(val, base + RNG_INT_MASK);
+}
+
static int bcm2835_rng_read(struct hwrng *rng, void *buf, size_t max,
bool wait)
{
@@ -46,10 +59,18 @@ static struct hwrng bcm2835_rng_ops = {
.read = bcm2835_rng_read,
};
+static const struct of_device_id bcm2835_rng_of_match[] = {
+ { .compatible = "brcm,bcm2835-rng"},
+ { .compatible = "brcm,bcm-nsp-rng", .data = nsp_rng_init},
+ {},
+};
+
static int bcm2835_rng_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
+ void (*rng_setup)(void __iomem *base);
+ const struct of_device_id *rng_id;
void __iomem *rng_base;
int err;
@@ -61,6 +82,15 @@ static int bcm2835_rng_probe(struct platform_device *pdev)
}
bcm2835_rng_ops.priv = (unsigned long)rng_base;
+ rng_id = of_match_node(bcm2835_rng_of_match, np);
+ if (!rng_id)
+ return -EINVAL;
+
+ /* Check for rng init function, execute it */
+ rng_setup = rng_id->data;
+ if (rng_setup)
+ rng_setup(rng_base);
+
/* set warm-up count & enable */
__raw_writel(RNG_WARMUP_COUNT, rng_base + RNG_STATUS);
__raw_writel(RNG_RBGEN, rng_base + RNG_CTRL);
@@ -90,10 +120,6 @@ static int bcm2835_rng_remove(struct platform_device *pdev)
return 0;
}
-static const struct of_device_id bcm2835_rng_of_match[] = {
- { .compatible = "brcm,bcm2835-rng", },
- {},
-};
MODULE_DEVICE_TABLE(of, bcm2835_rng_of_match);
static struct platform_driver bcm2835_rng_driver = {