diff options
Diffstat (limited to 'drivers/char/hw_random/bcm2835-rng.c')
| -rw-r--r-- | drivers/char/hw_random/bcm2835-rng.c | 47 |
1 files changed, 41 insertions, 6 deletions
diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c index 7192ec25f667..af2149273fe0 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 @@ -26,10 +27,24 @@ /* 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) { void __iomem *rng_base = (void __iomem *)rng->priv; + u32 max_words = max / sizeof(u32); + u32 num_words, count; while ((__raw_readl(rng_base + RNG_STATUS) >> 24) == 0) { if (!wait) @@ -37,8 +52,14 @@ static int bcm2835_rng_read(struct hwrng *rng, void *buf, size_t max, cpu_relax(); } - *(u32 *)buf = __raw_readl(rng_base + RNG_DATA); - return sizeof(u32); + num_words = readl(rng_base + RNG_STATUS) >> 24; + if (num_words > max_words) + num_words = max_words; + + for (count = 0; count < num_words; count++) + ((u32 *)buf)[count] = readl(rng_base + RNG_DATA); + + return num_words * sizeof(u32); } static struct hwrng bcm2835_rng_ops = { @@ -46,10 +67,19 @@ 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}, + { .compatible = "brcm,bcm5301x-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 +91,15 @@ 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 +129,6 @@ 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 = { |