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Christian Hewitt authored
GXM (S912) is a big-little design with CPUs 0-3 clocked at 1.5GHz and CPUs 4-7 at 1.0GHz. Adding capacity-dmips-mhz attributes allows the scheduler to factor the different clock speeds into capacity calculations and prefer the higher-clocked cluster to improve overall performance. This was inspired by the similar change for G12B [0] boards. The diference here is that all cores are A53's so the same dmips-mhz value is used. VIM2:~ # cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq 1512000 1512000 1512000 1512000 1000000 1000000 1000000 1000000 before: VIM2:~ # cat /sys/devices/system/cpu/cpu*/cpu_capacity 1024 1024 1024 1024 1024 1024 1024 1024 after: VIM2:~ # cat /sys/devices/system/cpu/cpu*/cpu_capacity 1024 1024 1024 1024 677 677 677 677 The after value matches my table-napkin calculation: (1000000 / 1512000 = 0.661) * 1024 = 677 [0] https://github.com/torvalds/linux/commit/6eeaf4d2452ec8b1ece58776812140734fc2e088 Signed-off-by:
Christian Hewitt <christianshewitt@gmail.com> Reviewed-by:
Neil Armstrong <narmstrong@baylibre.com> Signed-off-by:
Kevin Hilman <khilman@baylibre.com> Link: https://lore.kernel.org/r/20201124121740.25704-1-christianshewitt@gmail.com
Christian Hewitt authoredGXM (S912) is a big-little design with CPUs 0-3 clocked at 1.5GHz and CPUs 4-7 at 1.0GHz. Adding capacity-dmips-mhz attributes allows the scheduler to factor the different clock speeds into capacity calculations and prefer the higher-clocked cluster to improve overall performance. This was inspired by the similar change for G12B [0] boards. The diference here is that all cores are A53's so the same dmips-mhz value is used. VIM2:~ # cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq 1512000 1512000 1512000 1512000 1000000 1000000 1000000 1000000 before: VIM2:~ # cat /sys/devices/system/cpu/cpu*/cpu_capacity 1024 1024 1024 1024 1024 1024 1024 1024 after: VIM2:~ # cat /sys/devices/system/cpu/cpu*/cpu_capacity 1024 1024 1024 1024 677 677 677 677 The after value matches my table-napkin calculation: (1000000 / 1512000 = 0.661) * 1024 = 677 [0] https://github.com/torvalds/linux/commit/6eeaf4d2452ec8b1ece58776812140734fc2e088 Signed-off-by:
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