Ensure loop does not go forever in RNG#461
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| Max_Attempts : constant := 1000; | ||
| -- The above is arbitrary. It needs to be long enough that normal | ||
| -- behavior will not be flagged. Longer than that is fine. The point | ||
| -- is to not hang forever. |
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According to the documentation the RNG is guaranteed to be filled every 40 RNG clock cycles. Do we have an idea of how many iterations we could do within these 40 clock cycles?
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On 14-Apr-26 6:06 AM, JK wrote:
***@***.**** commented on this pull request.
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In arch/ARM/STM32/drivers/stm32-rng-polling.adb <https://github.com/
AdaCore/Ada_Drivers_Library#461#discussion_r3078978323>:
> + Max_Attempts : constant := 1000;
+ -- The above is arbitrary. It needs to be long enough that normal
+ -- behavior will not be flagged. Longer than that is fine. The point
+ -- is to not hang forever.
According to the documentation the RNG is guaranteed to be filled every
40 RNG clock cycles. Do we have an idea of how many iterations we could
do within these 40 clock cycles?
No, I don't. I chose 1000 on the assumption that it should be much more
than enough.
|
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the loop that checks for data ready is otherwise potentially infinite. not seen in practice, but no need to allow it.