]> asedeno.scripts.mit.edu Git - linux.git/commit
ARM: dts: r8a7790: add cpu capacity-dmips-mhz information
authorDietmar Eggemann <dietmar.eggemann@arm.com>
Wed, 30 Aug 2017 14:41:20 +0000 (15:41 +0100)
committerSimon Horman <horms+renesas@verge.net.au>
Thu, 12 Oct 2017 10:13:19 +0000 (12:13 +0200)
commit5bdc81259bb0efd5bd71820ef15757b70beae751
treea74abfd6dbb1528e707a3b7fd9c3c5506c13e4c6
parent2ee18841ff649e973d62afc6096b892396a676ef
ARM: dts: r8a7790: add cpu capacity-dmips-mhz information

The following 'capacity-dmips-mhz' dt property values are used:

Cortex-A15: 1024, Cortex-A7: 539

They have been derived form the cpu_efficiency values:

Cortex-A15: 3891, Cortex-A7: 2048

by scaling them so that the Cortex-A15s (big cores) use 1024.

The cpu_efficiency values were originally derived from the "Big.LITTLE
Processing with ARM Cortex™-A15 & Cortex-A7" white paper
(http://www.cl.cam.ac.uk/~rdm34/big.LITTLE.pdf). Table 1 lists 1.9x
(3891/2048) as the Cortex-A15 vs Cortex-A7 performance ratio for the
Dhrystone benchmark.

The following platform is affected once cpu-invariant accounting
support is re-connected to the task scheduler:

r8a7790-lager

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
arch/arm/boot/dts/r8a7790.dtsi