On Wed, 24 Mar 2010, Carl-Daniel Hailfinger wrote:
Ping? This cleanup is part 1/2 to make flashrom work with clang and unbreak the delay calculation. If the new style code is OK, I'll submit part 2/2 which makes heavy use of the new style code to get timing accuracy of +-10% even in case of CPU speed variations. Considering that the current code relies on the dumbness of the optimizer in the C compiler and still manages to make all delays twice as long as intended, I hope we can get the fixed code in before 0.9.2.
Imo looks fine, on one machine and nic3com i get Calibrating delay loop... 95M loops per second, 10 myus = 23 us, 100 myus = 202 us, 1000 myus = 2042 us, 10000 myus = 20020 us, OK. same machine but mainboard interface (internal) Calibrating delay loop... 94M loops per second, 10 myus = 23 us, 100 myus = 199 us, 1000 myus = 1972 us, 10000 myus = 19784 us, OK.
still bit far from 10uS = 10myus
anyway i think it won't break anything
Acked-by: Maciej Pijanka maciej.pijanka@gmail.com
On 06.03.2010 04:28, Carl-Daniel Hailfinger wrote:
Note: This patch is the first step towards a better delay loop calibration which will work regardless of how smart the C compiler is.
Clean up code duplication and measure timing of 10/100/1000/10000 us delays. Add copyright notices for my past and current work on this file.
If possible, please run the following command a few times and mail the output to flashrom@flashrom.org flashrom -V|grep delay
Regards, Carl-Daniel