Fixes committed for two reported issues

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Fixes committed for two reported issues

Postby Ultibo » Fri Oct 14, 2016 4:29 am

In response to two reported issues from the latest Ultibo core release we have just committed a minor update which corrects those items.


Horizontal lines and spots shown on console immediately after boot

Following the latest round of framebuffer enhancements it was observed that both console windows and the console background could show random horizontal lines and spots immediately after boot, any further console output after boot would be normal and not show any symptoms of the random spots.

The issue was traced to the handling of cache cleaning and/or invalidation by the framebuffer code during boot, in particular if a DMA transfer was requested but DMA was not yet available or the system initialization was not completed. Adjusting the handling of the flag FRAMEBUFFER_TRANSFER_DMA resolves the issue in all cases and the random effects are no longer seen in any tests.

ARM timer device driver does not handle non exact divisor values correctly

The new ARM Timer device driver added in the last commit was not correctly dealing with the case where the requested clock rate was not an exact multiple of the core clock frequency. As an example, if the core clock is 400MHz (as is the case on a Raspberry Pi 3) and the requested clock rate is 101MHz then the divisor value calculated would produce an actual clock rate of 133.333MHz and yet still return ERROR_SUCCESS, in addition the TimerDeviceGetRate() function would return 101MHz as the current rate.

The code for the TimerDeviceSetRate() rate function has been enhanced to check that the requested clock rate is an exact multiple of the core clock rate and return a new error code (ERROR_NOT_EXACT) if it is not, the function will still set the clock rate as calculated but will also update the value returned by TimerDeviceGetRate() to reflect the actual clock rate set. | Make something amazing
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Re: Fixes committed for two reported issues

Postby mark » Mon Oct 31, 2016 9:56 am

Thanks, I can confirm the fix for the timer rate setting. Mark.

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