Change Details

(WIP, please help me improve this, or just do it better :D) `AcpiOsMapMemory` is used for device memory when e.g. an `_INI` method wants to access physical memory. However, aarch64 `pmap_mapbios` is hardcoded to writeback, which is no good. We need to default to device memory and use EFI memory map attributes to detect different modes. This fixes XHCI initialization on the Raspberry Pi 4 UEFI firmware (https://github.com/pftf/RPi4/issues/50). Inspired by NetBSD: https://github.com/NetBSD/src/blob/792df501ab0f93d73372a9bc2c7f19ccb733c1e5/sys/arch/arm/acpi/acpi_machdep.c#L70 (XXX: currently the patch would *only* work on arm64, haha)

(WIP, please help me improve this, or just do it better :D) `AcpiOsMapMemory` is used for device memory when e.g. an `_INI` method wants to access physical memory. However, aarch64 `pmap_mapbios` is hardcoded to writeback, which is no good. We need to default to device memory and use EFI memory map attributes to detect different modes. This fixes XHCI initialization on the Raspberry Pi 4 UEFI firmware (https://github.com/pftf/RPi4/issues/50). Inspired by NetBSD: https://github.com/NetBSD/src/blob/792df501ab0f93d73372a9bc2c7f19ccb733c1e5/sys/arch/arm/acpi/acpi_machdep.c#L70

(WIP, please help me improve this, or just do it better :D) `AcpiOsMapMemory` is used for device memory when e.g. an `_INI` method wants to access physical memory. However, aarch64 `pmap_mapbios` is hardcoded to writeback, which is no good. We need to default to device memory and use EFI memory map attributes to detect different modes. This fixes XHCI initialization on the Raspberry Pi 4 UEFI firmware (https://github.com/pftf/RPi4/issues/50). Inspired by NetBSD: https://github.com/NetBSD/src/blob/792df501ab0f93d73372a9bc2c7f19ccb733c1e5/sys/arch/arm/acpi/acpi_machdep.c#L70 (XXX: currently the patch would *only* work on arm64, haha)