[PATCH v2 2/2] hwrng: iproc-rng200 - Add Broadcom IPROC RNG driver

Scott Branden sbranden at broadcom.com
Mon Mar 2 11:41:05 PST 2015

Hi Arnd,

Thanks for the suggested change.

On 15-02-28 11:31 AM, Arnd Bergmann wrote:
> On Saturday 28 February 2015 08:01:11 Scott Branden wrote:
>>> The udelay(10) that the other drivers have seems about appropriate then,
>>> and we can independently think of a way to refine the interface.
>>> Please add a comment that explains the rate. Also, is there some kind
>>> of FIFO present in the hwrng device? If it can store close to 1ms work
>>> of data (1000 bits), you can just use an msleep(1) to wait for the
>>> pool to recover.
>> FIFO is 512 bits.  I will look as to whether we can live with 1/2
>> throughput.
> In that case, I think usleep_range(min(len * 8, 500), 500)) would be
> a good compromise: it waits at most until the fifo is full, but might
> return earlier if enough bits are available to fulfill the request.
OK, will change in next version.
> 	Arnd

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