audk/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe
Sami Mujawar 015be4075f PcAtChipsetPkg: Add MMIO Support to RTC driver
Some virtual machine managers like Kvmtool emulate the MC146818
RTC controller in the MMIO space so that architectures that do
not support I/O Mapped I/O can use the RTC. This patch adds MMIO
support to the RTC controller driver.

The PCD PcdRtcUseMmio has been added to select I/O or MMIO support.
  If PcdRtcUseMmio is:
    TRUE  - Indicates the RTC port registers are in MMIO space.
    FALSE - Indicates the RTC port registers are in I/O space.
            Default is I/O space.

Additionally two new PCDs PcdRtcIndexRegister64 and
PcdRtcTargetRegister64 have been introduced to provide the base
address for the RTC registers in the MMIO space.

When MMIO support is selected (PcdRtcUseMmio == TRUE) the driver
converts the pointers to the RTC MMIO registers so that the
RTC registers are accessible post ExitBootServices.

Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
2020-10-16 17:21:04 +00:00
..
PcRtc.c PcAtChipsetPkg: Add MMIO Support to RTC driver 2020-10-16 17:21:04 +00:00
PcRtc.h
PcRtc.uni
PcRtcEntry.c PcAtChipsetPkg: Add MMIO Support to RTC driver 2020-10-16 17:21:04 +00:00
PcRtcExtra.uni
PcatRealTimeClockRuntimeDxe.inf PcAtChipsetPkg: Add MMIO Support to RTC driver 2020-10-16 17:21:04 +00:00