Hi Pete,<br /><br />I've submitted this patch because the mini UART serial console produces garbage since UEFI v1.25 (due to the wrong baud rate).&nbsp;<br />It has been tested on the firmware shipped with UEFI v1.24 and it works fine. I don't see any reason to test it on older versions than this.<br /><br />The core clock is not fixed. I've made PcdSerialClockRate patchable here:<br />
<blockquote><span style="white-space: pre-wrap;">@@ -465,6 +464,9 @@ [PcdsFixedAtBuild.common]</span><br style="white-space: pre-wrap;" /><span style="white-space: pre-wrap;"> gEfiMdeModulePkgTokenSpaceGuid.PcdFirmwareVendor|L"EDK2"</span><br style="white-space: pre-wrap;" /><span style="white-space: pre-wrap;"> gEfiMdeModulePkgTokenSpaceGuid.PcdSetNxForStack|TRUE</span><br style="white-space: pre-wrap;" /><br style="white-space: pre-wrap;" /><span style="white-space: pre-wrap;">+[PcdsPatchableInModule]</span><br style="white-space: pre-wrap;" /><span style="white-space: pre-wrap;">+ gEfiMdeModulePkgTokenSpaceGuid.PcdSerialClockRate|500000000</span><br style="white-space: pre-wrap;" /><span style="white-space: pre-wrap;">+<br /></span></blockquote>
500 MHz is the default clock rate (assuming it hasn't been changed in config.txt). <br />The PCD gets patched in both the PEI and DXE phases to the value read from mailbox.&nbsp;