#!/bin/sh # This script relaxes iommu for the devices, relaxing memory # protection, but we consider it a fine tradeoff because those # hardware blocks don't have firmware on them. # It Increases eMMC speed by 15% according to gnome disks benchmark # with sample size 1000 MiB and number of samples 2. iommus=" /sys/devices/platform/soc@0/7c4000.mmc/iommu_group/type /sys/devices/platform/soc@0/8804000.mmc/iommu_group/type /sys/devices/platform/soc@0/a6f8800.usb/a600000.usb/iommu_group/type " for iommu in $iommus; do [ -f "$iommu" ] && echo "DMA-FQ" > "$iommu" done