WORLDTECHDeveloper Releases Linux Tool to Enable Resizable BAR on Intel Arc GPUs
Developer Rod Burlamaqui has released arc-rebar, a Linux tool that enables Resizable BAR for Intel Arc graphics cards on motherboards that never offered the option, according to a report by TechPowerUp.
How the tool works
The tool runs from the initramfs at every boot, before the GPU driver loads, and leaves the BIOS, the kernel and Intel's drivers untouched. Unlike earlier workarounds such as ReBarUEFI, it does not need to be added to the motherboard's firmware.
The fix targets the PCIe switch built into Arc cards, whose small upstream BAR prevents Linux from enlarging the GPU's memory window. arc-rebar writes the card's ReBAR register and then removes and rescans the root port.
Why Resizable BAR matters for Arc
Intel Arc cards depend heavily on Resizable BAR. Intel once told buyers of Alchemist cards without the feature to choose other vendors, and TechPowerUp's review of the B580 listed it as required for good performance.