\textbf{\DIFadd{Description}}\DIFadd{: Performs change of PMIO register base address
on a customised PCI serial device.
}
\DIFadd{The patch changes the PMIO register base address that the XNU kernel uses for serial input and output,
from that of the default built-in COM1 serial port }\texttt{\DIFadd{0x3F8}}\DIFadd{, to the base address stored in the first
IO BAR of a specified PCI device or to a specific base address (e.g. }\texttt{\DIFadd{0x2F8}}\DIFadd{for COM2).
}
\emph{\DIFadd{Note}}\DIFadd{: By default, serial logging is disabled. }\texttt{\DIFadd{serial=3}}\DIFadd{boot argument, which enables serial input and output,
should be used for XNU to print logs to the serial port.
}
\emph{\DIFadd{Note 2}}\DIFadd{: In addition to this patch, kext }\texttt{\DIFadd{Apple16X50PCI0}}\DIFadd{should be prevented from attaching
to have }\texttt{\DIFadd{kprintf}}\DIFadd{method working properly. This can be achieved by setting (i.e. }\texttt{\DIFadd{Delete}}\DIFadd{, then }\texttt{\DIFadd{Add}}\DIFadd{)
the }\texttt{\DIFadd{class-code}}\DIFadd{property of the PCI serial port device to }\texttt{\DIFadd{FFFFFFFF}}\DIFadd{in }\texttt{\DIFadd{DeviceProperties}}\DIFadd{section.
As an alternative solution, a codeless kext }\texttt{\DIFadd{PCIeSerialDisable.kext}}\DIFadd{shown in the spoiler }\texttt{\DIFadd{PCIeSerialDisable.kext/Contents/Info.plist}}\DIFadd{at
}\href{https://github.com/acidanthera/bugtracker/issues/1954}{\DIFadd{acidanthera/bugtracker\#1954}}\DIFadd{, may also be used.
}
\emph{\DIFadd{Note 3}}\DIFadd{: For this patch to be correctly applied, }\texttt{\DIFadd{Override}}
\DIFadd{must be enabled with all keys properly set in }\texttt{\DIFadd{Custom}}\DIFadd{, under section }\texttt{\DIFadd{Misc->Serial}}\DIFadd{.
}
\emph{\DIFadd{Note 4}}\DIFadd{: This patch is for PMIO support and is therefore not applied if }\texttt{\DIFadd{UseMmio}}\DIFadd{under section }\texttt{\DIFadd{Misc->Serial->Custom}}\DIFadd{is false.
For MMIO, there are boot arguments }\texttt{\DIFadd{pcie\_mmio\_uart=ADDRESS}}\DIFadd{and }\texttt{\DIFadd{mmio\_uart=ADDRESS}}\DIFadd{that allow the kernel to use MMIO for serial port access.
}
\emph{\DIFadd{Note 5}}\DIFadd{: The serial baud rate must be correctly set in both }\texttt{\DIFadd{BaudRate}}\DIFadd{under section }\texttt{\DIFadd{Misc->Serial->Custom}}\DIFadd{and via
}\texttt{\DIFadd{serialbaud=VALUE}}\DIFadd{boot argument, both of which should match against each other. The default baud rate is }\texttt{\DIFadd{115200}}\DIFadd{.
}
\item
\DIFaddend\texttt{CustomSMBIOSGuid}\\
\textbf{Type}: \texttt{plist\ boolean}\\
\textbf{Failsafe}: \texttt{false}\\
\textbf{Requirement}: 10.4\\
...
...
@@ -3230,14 +3267,26 @@ the default boot entry choice will remain changed until the next manual reconfig
\textbf{\DIFadd{Description}}\DIFadd{: Perform serial port initialisation and
configure PCD values required by }\texttt{\DIFadd{BaseSerialPortLib16550}}\DIFadd{for serial ports to properly function.
Values are listed and described in the }\hyperref[miscserialprops]{Serial Properties}\DIFadd{and }\hyperref[miscserialcustprops]{Serial Custom Properties}\DIFadd{section below.
}
\DIFadd{By enabling }\texttt{\DIFadd{Init}}\DIFadd{, this section ensures that the serial port is initialised when it is not done by firmware.
In order for OpenCore to print logs to the serial port, bit }\texttt{\DIFadd{3}}\DIFadd{(i.e. serial logging) for }\texttt{\DIFadd{Target}}
\DIFadd{under section }\texttt{\DIFadd{Misc->Debug}}\DIFadd{must be set.
}
\DIFadd{This section overrides the PCD values listed in
Refer to }\href{https://github.com/acidanthera/audk/blob/master/MdeModulePkg/MdeModulePkg.dec}{\DIFadd{MdeModulePkg.dec}}\DIFadd{for the explanations of each key.
\DIFadd{When debugging with serial ports, }\texttt{\DIFadd{BaseSerialPortLib16550}}\DIFadd{only recognises internal ones
provided by the motherboard by default. If the option }\texttt{\DIFadd{Override}}\DIFadd{is enabled, this section will override the PCD values listed in
\DIFadd{such that external serial ports (e.g. from a PCI card) will also function properly. Specifically, when troubleshooting macOS,
in addition to overriding these PCD values, it is also necessary to turn the }\texttt{\DIFadd{CustomPciSerialDevice}}\DIFadd{kernel quirk on in order for
the XNU to use such exterior serial ports.
}
\DIFadd{Refer to }\href{https://github.com/acidanthera/audk/blob/master/MdeModulePkg/MdeModulePkg.dec}{\DIFadd{MdeModulePkg.dec}}\DIFadd{for the explanations of each key.
\item\texttt{lapic\_dont\_panic=1}(disable lapic spurious interrupt panic on AP cores)
\item\texttt{panic\_on\_display\_hang=1}(trigger panic on display hang)
\item\texttt{panic\_on\_gpu\_hang=1}(trigger panic on GPU hang)
\item\texttt{slide=VALUE}(manually set KASLR slide)
\item\DIFaddbegin\texttt{\DIFadd{serial=VALUE}}\DIFadd{(configure serial logging mode)--- The following bits are used by XNU:
}\begin{itemize}
\tightlist
\item\texttt{\DIFadd{0x01}}\DIFadd{(}\texttt{\DIFadd{SERIALMODE\_OUTPUT}}\DIFadd{, bit }\texttt{\DIFadd{0}}\DIFadd{)--- Enable serial output.
}\item\texttt{\DIFadd{0x02}}\DIFadd{(}\texttt{\DIFadd{SERIALMODE\_INPUT}}\DIFadd{, bit }\texttt{\DIFadd{1}}\DIFadd{)--- Enable serial input.
}\item\texttt{\DIFadd{0x04}}\DIFadd{(}\texttt{\DIFadd{SERIALMODE\_SYNCDRAIN}}\DIFadd{, bit }\texttt{\DIFadd{2}}\DIFadd{)--- Enable serial drain synchronisation.
}\item\texttt{\DIFadd{0x08}}\DIFadd{(}\texttt{\DIFadd{SERIALMODE\_BASE\_TTY}}\DIFadd{, bit }\texttt{\DIFadd{3}}\DIFadd{)--- Load Base/Recovery/FVUnlock TTY.
}\item\texttt{\DIFadd{0x10}}\DIFadd{(}\texttt{\DIFadd{SERIALMODE\_NO\_IOLOG}}\DIFadd{, bit }\texttt{\DIFadd{4}}\DIFadd{)--- Prevent IOLogs writing to serial.
}\end{itemize}
\item\DIFaddend\texttt{slide=VALUE}(manually set KASLR slide)
\item\texttt{spin\_wait\_for\_gpu=1}(reduces GPU timeout on high load)
\item\texttt{-amd\_no\_dgpu\_accel}(alternative to \href{https://github.com/acidanthera/WhateverGreen}{WhateverGreen}'s \texttt{-radvesa} for new GPUs)
...
...
@@ -8932,7 +9025,9 @@ than 1 meter to avoid output corruption. To additionally enable XNU kernel seria
\tightlist
\item Refer to \texttt{boot-args} values such as \texttt{debug=0x100}, \texttt{keepsyms=1},
\texttt{-v}, and similar.
\item Do not forget about \texttt{AppleDebug} and \texttt{ApplePanic} properties.
\item Do not forget about \texttt{AppleDebug} and \texttt{ApplePanic} properties\DIFaddbegin\DIFadd{.
}\item\DIFadd{For macOS to correctly recognise and set up serial ports, the }\texttt{\DIFadd{CustomPciSerialDevice}}\DIFadd{quirk
may be enabled when a PCI serial port card is installed}\DIFaddend .
\item Take care of \texttt{Booter}, \texttt{Kernel}, and \texttt{UEFI} quirks.
\item Consider using serial port to inspect early kernel boot failures. For this
\texttt{debug=0x108}, \texttt{serial=5}, and \texttt{msgbuf=1048576} boot arguments are needed.
