From 6d6b0f9d70bde300fb211aba2612bc4ca8f2c308 Mon Sep 17 00:00:00 2001 From: Matt DeVillier Date: Thu, 19 Sep 2024 09:58:18 -0500 Subject: [PATCH] universal_payload.rst: Add ClockRate field to serial port info Add a ClockRate field to the UNIVERSAL_PAYLOAD_SERIAL_PORT_INFO struct to allow the host firmware to pass the serial clock rate to the payload in order to properly initialize the serial/debug port. This field is necessary because AMD Zen platform devices do not use the same clock rate as Intel devices. Signed-off-by: Matt DeVillier --- source/2_universal_payload.rst | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/source/2_universal_payload.rst b/source/2_universal_payload.rst index 9ec487b..6b50d85 100644 --- a/source/2_universal_payload.rst +++ b/source/2_universal_payload.rst @@ -1145,6 +1145,7 @@ to payload. UINT8 RegisterStride; UINT32 BaudRate; EFI_PHYSICAL_ADDRESS RegisterBase; + UINT32 ClockRate; } UNIVERSAL_PAYLOAD_SERIAL_PORT_INFO; #pragma pack() @@ -1153,9 +1154,9 @@ to payload. ``Header`` -Header.Revision is 1. +Header.Revision is 2. -Header.Length is 18. +Header.Length is 22. ``UseMmio`` @@ -1179,6 +1180,10 @@ Set to 0 to use the default baud rate 115200. Base address of 16550 serial port registers in MMIO or I/O space. +``ClockRate`` + +The crystal or input frequency to the chip containing the UART. + PCI Root Bridges %%%%%%%%%%%%%%%%%%%%