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@@ -39,14 +39,6 @@ Linux kernel as part of a FIT image. It also supports a compressed zImage.
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U-Boot supports loading an x86 VxWorks kernel. Please check README.vxworks
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for more details.
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-Build Instructions for U-Boot as coreboot payload
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--------------------------------------------------
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-Building U-Boot as a coreboot payload is just like building U-Boot for targets
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-on other architectures, like below:
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-
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-$ make coreboot_defconfig
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-$ make all
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-
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Build Instructions for U-Boot as BIOS replacement (bare mode)
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-------------------------------------------------------------
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Building a ROM version of U-Boot (hereafter referred to as u-boot.rom) is a
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@@ -82,35 +74,6 @@ Device Tree Control --->
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...
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(qemu-x86_q35) Default Device Tree for DT control
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-Test with coreboot
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-------------------
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-For testing U-Boot as the coreboot payload, there are things that need be paid
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-attention to. coreboot supports loading an ELF executable and a 32-bit plain
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-binary, as well as other supported payloads. With the default configuration,
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-U-Boot is set up to use a separate Device Tree Blob (dtb). As of today, the
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-generated u-boot-dtb.bin needs to be packaged by the cbfstool utility (a tool
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-provided by coreboot) manually as coreboot's 'make menuconfig' does not provide
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-this capability yet. The command is as follows:
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-
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-# in the coreboot root directory
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-$ ./build/util/cbfstool/cbfstool build/coreboot.rom add-flat-binary \
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- -f u-boot-dtb.bin -n fallback/payload -c lzma -l 0x1110000 -e 0x1110000
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-
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-Make sure 0x1110000 matches CONFIG_SYS_TEXT_BASE, which is the symbol address
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-of _x86boot_start (in arch/x86/cpu/start.S).
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-
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-If you want to use ELF as the coreboot payload, change U-Boot configuration to
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-use CONFIG_OF_EMBED instead of CONFIG_OF_SEPARATE.
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-
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-To enable video you must enable these options in coreboot:
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-
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- - Set framebuffer graphics resolution (1280x1024 32k-color (1:5:5))
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- - Keep VESA framebuffer
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-
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-At present it seems that for Minnowboard Max, coreboot does not pass through
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-the video information correctly (it always says the resolution is 0x0). This
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-works correctly for link though.
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-
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Test with QEMU for bare mode
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----------------------------
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QEMU is a fancy emulator that can enable us to test U-Boot without access to
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