diff options
Diffstat (limited to 'src/cpu/Kconfig')
| -rw-r--r-- | src/cpu/Kconfig | 88 |
1 files changed, 84 insertions, 4 deletions
diff --git a/src/cpu/Kconfig b/src/cpu/Kconfig index baf686ea75..1ed721f7e0 100644 --- a/src/cpu/Kconfig +++ b/src/cpu/Kconfig @@ -62,10 +62,90 @@ config SSE2 streaming SIMD instructions. Some parts of coreboot can be built with more efficient code if SSE2 instructions are available. -config MICROCODE_IN_CBFS - bool "Look for microcode in CBFS" +endif # ARCH_X86 + +config CPU_MICROCODE_IN_CBFS + bool default n + +choice + prompt "Include CPU microcode in CBFS" + default CPU_MICROCODE_CBFS_GENERATE if CPU_MICROCODE_IN_CBFS + default CPU_MICROCODE_CBFS_NONE if !CPU_MICROCODE_IN_CBFS + +config CPU_MICROCODE_CBFS_GENERATE + bool "Generate from tree" help - Load microcode updates from CBFS instead of compiling them in. + Select this option if you want microcode updates to be assembled when + building coreboot and included in the final image as a separate CBFS + file. Microcode will not be hard-coded into ramstage. -endif # ARCH_X86 + The microcode file and may be removed from the ROM image at a later + time with cbfstool, if desired. + + If unsure, select this option. + +config CPU_MICROCODE_CBFS_EXTERNAL + bool "Include external microcode file" + help + Select this option if you want to include an external file containing + the CPU microcode. This will be included as a separate file in CBFS. + A word of caution: only select this option if you are sure the + microcode that you have is newer than the microcode shipping with + coreboot. + + The microcode file and may be removed from the ROM image at a later + time with cbfstool, if desired. + + If unsure, select "Generate from tree" + +config CPU_MICROCODE_FILE + string "Path and filename of CPU microcode" + depends on CPU_MICROCODE_CBFS_EXTERNAL + default "cpu_microcode.bin" + help + The path and filename of the file containing the CPU microcode. + +config CPU_MICROCODE_CBFS_NONE + bool "Do not include microcode updates" + help + Select this option if you do not want CPU microcode included in CBFS. + Note that for some CPUs, the microcode is hard-coded into the source + tree and is not loaded from CBFS. In this case, microcode will still + be updated. There is a push to move all microcode to CBFS, but this + change is not implemented for all CPUs. + + This option currently applies to: + - Intel SandyBridge/IvyBridge + - VIA Nano + + Microcode may be added to the ROM image at a later time with cbfstool, + if desired. + + If unsure, select "Generate from tree" + + The GOOD: + Microcode updates intend to solve issues that have been discovered + after CPU production. The expected effect is that systems work as + intended with the updated microcode, but we have also seen cases where + issues were solved by not applying microcode updates. + + The BAD: + Note that some operating system include these same microcode patches, + so you may need to also disable microcode updates in your operating + system for this option to have an effect. + + The UGLY: + A word of CAUTION: some CPUs depend on microcode updates to function + correctly. Not updating the microcode may leave the CPU operating at + less than optimal performance, or may cause outright hangups. + There are CPUs where coreboot cannot properly initialize the CPU + without microcode updates + For example, if running with the factory microcode, some Intel + SandyBridge CPUs may hang when enabling CAR, or some VIA Nano CPUs + will hang when changing the frequency. + + Make sure you have a way of flashing the ROM externally before + selecting this option. + +endchoice |