diff options
Diffstat (limited to 'drivers/char/hw_random/amd-rng.c')
| -rw-r--r-- | drivers/char/hw_random/amd-rng.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/char/hw_random/amd-rng.c b/drivers/char/hw_random/amd-rng.c index 556fd81fa815..c422e870dc52 100644 --- a/drivers/char/hw_random/amd-rng.c +++ b/drivers/char/hw_random/amd-rng.c @@ -28,6 +28,7 @@ #include <linux/kernel.h> #include <linux/pci.h> #include <linux/hw_random.h> +#include <linux/delay.h> #include <asm/io.h> @@ -52,11 +53,18 @@ MODULE_DEVICE_TABLE(pci, pci_tbl); static struct pci_dev *amd_pdev; -static int amd_rng_data_present(struct hwrng *rng) +static int amd_rng_data_present(struct hwrng *rng, int wait) { u32 pmbase = (u32)rng->priv; + int data, i; - return !!(inl(pmbase + 0xF4) & 1); + for (i = 0; i < 20; i++) { + data = !!(inl(pmbase + 0xF4) & 1); + if (data || !wait) + break; + udelay(10); + } + return data; } static int amd_rng_data_read(struct hwrng *rng, u32 *data) |