From cd8267b69cc51d204c4a9b62fce490abdc34ec59 Mon Sep 17 00:00:00 2001 From: Iru Cai Date: Fri, 21 May 2021 11:40:55 +0800 Subject: Documentation: add Intel Broadwell Change-Id: I0b1c29162a64030b5c100368f2471702e22b8311 Signed-off-by: Iru Cai Reviewed-on: https://review.coreboot.org/c/coreboot/+/54744 Tested-by: build bot (Jenkins) Reviewed-by: Angel Pons --- Documentation/soc/intel/broadwell/blobs.md | 41 ++++++++++++++++++++++++++++++ Documentation/soc/intel/broadwell/index.md | 7 +++++ 2 files changed, 48 insertions(+) create mode 100644 Documentation/soc/intel/broadwell/blobs.md create mode 100644 Documentation/soc/intel/broadwell/index.md (limited to 'Documentation/soc/intel/broadwell') diff --git a/Documentation/soc/intel/broadwell/blobs.md b/Documentation/soc/intel/broadwell/blobs.md new file mode 100644 index 0000000000..b9f99afe66 --- /dev/null +++ b/Documentation/soc/intel/broadwell/blobs.md @@ -0,0 +1,41 @@ +# Blobs used in Intel Broadwell boards + +All Broadwell boards supported by coreboot require two proprietary blobs. +In a coreboot image of a Broadwell board, the blobs are named `mrc.bin` and +`refcode` in CBFS. + +`mrc.bin` is run in romstage to initialize the memory. It is placed at a fixed +address in CBFS and is loaded at a fixed address in memory. + +`refcode` is run in ramstage to initialize the system agent and the PCH. It is +a relocatable ELF object. + +## Obtaining the blobs + +Both `mrc.bin` and `refcode` can be obtained from a coreboot image of a Broadwell +board, for example a Purism Librem 13 v1 coreboot image from [MrChromebox]. + + cbfstool coreboot_*.rom extract -f broadwell-mrc.bin -n mrc.bin + cbfstool coreboot_*.rom extract -m x86 -f broadwell-refcode.elf -n fallback/refcode + +## SPD Addresses + +The SPD addresses in Broadwell `pei_data` struct are similar to [Haswell]. + +## Intel GbE support + +Unlike Haswell boards, the `pei_data` struct of Broadwell doesn't have `gbe_enable` +field. For boards with an Intel GbE device, a modification of `refcode` is needed, +otherwise `refcode` will disable the Intel GbE device and the OS cannot find it +in the list of PCI devices. + +## Use Broadwell SoC code for Haswell ULT boards + +Haswell ULT boards can use Broadwell SoC code. To use Broadwell code for Haswell ULT +boards, `devicetree.cb` file and `pei_data` code need to be ported to Broadwell, and +build the code with Broadwell `mrc.bin` and `refcode` instead of using Haswell `mrc.bin`. + +Broadwell SoC code doesn't support non-ULT Haswell or non-ULT Broadwell boards. + +[MrChromebox]: https://mrchromebox.tech/ +[Haswell]: ../../../northbridge/intel/haswell/mrc.bin.md diff --git a/Documentation/soc/intel/broadwell/index.md b/Documentation/soc/intel/broadwell/index.md new file mode 100644 index 0000000000..11a3ce1058 --- /dev/null +++ b/Documentation/soc/intel/broadwell/index.md @@ -0,0 +1,7 @@ +# Intel Broadwell documentation + +This section describes the Intel Broadwell SoC. + +## Proprietary blobs + +- [mrc.bin and refcode](blobs.md) -- cgit v1.2.3