b7e69a2e56
Intel Speed Shift Technology is a new mechanism that replaces Legacy P-state. ISST allows OS hints about energy/performance preference. H/W performs the actual P-state control (autonomous) 1. Optimization frequency seclection for low residency workloads, no longer a static knee point. 2. Optimized frequency selection for best energy to performance trade offs. 3. Kick down frequency (from idle) fpr best responsiveness while taking energy consumption init account. Coreboot's responsiblity is to configure MSR 0x1AA ISST_EN bits which will reflect in CPUID.06h:EAX[Bit 7] that driver checkes and enable HWP accordingly. BUG=chrome-os-partner:47517 BRANCH=None TEST=Booted kunimitsu and verify HWP getting enabled/disabled using Intel P-state driver. Change-Id: I91722aa1077f4ef6c8620b103be3e29cfcd974e5 Signed-off-by: Patrick Georgi <pgeorgi@google.com> Original-Commit-Id: aa7d004cb2e19047e4434e3e2544cf69393ce28f Original-Change-Id: Ie617da337babde7f196a7af712263e37f7eed56f Original-Signed-off-by: Robbie Zhang <robbie.zhang@intel.com> Original-Signed-off-by: Subrata Banik <subrata.banik@intel.com> Original-Reviewed-on: https://chromium-review.googlesource.com/313107 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Reviewed-by: Wenkai Du <wenkai.du@intel.com> Reviewed-on: https://review.coreboot.org/13835 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org> |
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| broadcom/cygnus | ||
| imgtec/pistachio | ||
| intel | ||
| marvell | ||
| mediatek/mt8173 | ||
| nvidia | ||
| qualcomm/ipq806x | ||
| rockchip/rk3288 | ||
| samsung | ||
| ucb/riscv | ||