FreeBSD base system does not provide an ACPI handler for the PC/AT RTC/CMOS device with PnP ID PNP0B00; on some HP laptops, the absence of this handler causes suspend/resume and poweroff(8) to hang or fail [1], [2]. On these laptops EC _REG method queries the RTC date/time registers via ACPI before suspending/powering off. The handler should be registered before acpi_ec driver is loaded. This change adds handler to access CMOS RTC operation region described in section 9.15 of ACPI-6.2 specification [3]. It is installed only for ACPI version of atrtc(4) so it should not affect old ACPI-less i386 systems. It is possible to disable the handler with loader tunable: debug.acpi.disabled=atrtc Informational debugging printf can be enabled by setting hw.acpi.verbose=1 in loader.conf [1] https://wiki.freebsd.org/Laptops/HP_Envy_6Z-1100 [2] https://wiki.freebsd.org/Laptops/HP_Notebook_15-af104ur [3] https://uefi.org/sites/default/files/resources/ACPI_6_2.pdf PR: 207419, 213039 Submitted by: Anthony Jenkins <Scoobi_doo@yahoo.com> Reviewed by: ian Discussed on: acpi@, 2013-2015, several threads MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D19314 |
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acpica | ||
bios | ||
cpufreq | ||
include | ||
iommu | ||
isa | ||
pci | ||
x86 | ||
xen |