crypto: ccp - Refactor code supporting the CCP's RNG
Make the RNG support code common (where possible) in preparation for adding a v5 device. Signed-off-by: Gary R Hook <gary.hook@amd.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
@@ -409,6 +409,34 @@ struct ccp_device *ccp_alloc_struct(struct device *dev)
|
||||
return ccp;
|
||||
}
|
||||
|
||||
int ccp_trng_read(struct hwrng *rng, void *data, size_t max, bool wait)
|
||||
{
|
||||
struct ccp_device *ccp = container_of(rng, struct ccp_device, hwrng);
|
||||
u32 trng_value;
|
||||
int len = min_t(int, sizeof(trng_value), max);
|
||||
|
||||
/* Locking is provided by the caller so we can update device
|
||||
* hwrng-related fields safely
|
||||
*/
|
||||
trng_value = ioread32(ccp->io_regs + TRNG_OUT_REG);
|
||||
if (!trng_value) {
|
||||
/* Zero is returned if not data is available or if a
|
||||
* bad-entropy error is present. Assume an error if
|
||||
* we exceed TRNG_RETRIES reads of zero.
|
||||
*/
|
||||
if (ccp->hwrng_retries++ > TRNG_RETRIES)
|
||||
return -EIO;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Reset the counter and save the rng value */
|
||||
ccp->hwrng_retries = 0;
|
||||
memcpy(data, &trng_value, len);
|
||||
|
||||
return len;
|
||||
}
|
||||
|
||||
#ifdef CONFIG_PM
|
||||
bool ccp_queues_suspended(struct ccp_device *ccp)
|
||||
{
|
||||
|
Reference in New Issue
Block a user