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A comment on PSPTool Is a Swiss Army Knife for the Firmware of the AMD Secure Processor. Parent comment

Re:PSPTool Is a Swiss Army Knife for the Firmware of the AMD... by pgeorgi on Wednesday June 05, 2019 @03:49PM (#20108416)
The PSP is responsible for memory training and re-enabling after wake-up. So neutralizing might work (given that signatures can be tricked), but you have to be very careful to keep a sizable set of modules alive.
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Re:PSPTool Is a Swiss Army Knife for the Firmware of the AMD... by mehrdadn on Wednesday June 05, 2019 @04:39PM (#20108885)
What is "memory training"?
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Re:PSPTool Is a Swiss Army Knife for the Firmware of the AMD... by vardump on Wednesday June 05, 2019 @04:58PM (#20109062)
It's related to correcting DDR memory signal timing / clock skew.
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Re:PSPTool Is a Swiss Army Knife for the Firmware of the AMD... by mehrdadn on Wednesday June 05, 2019 @05:07PM (#20109150)
Oh it's the timing calibration thing that happens on initialization? Didn't realize that's called memory training haha cool!
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Re:PSPTool Is a Swiss Army Knife for the Firmware of the AMD... by rurban on Thursday June 06, 2019 @12:31AM (#20111610)
That's probably what the unsigned data bodies are for. This data needs to be on the fast path.
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Re:PSPTool Is a Swiss Army Knife for the Firmware of the AMD... by agapon on Wednesday June 05, 2019 @05:12PM (#20109203)
Are you sure? I thought that that was what AGESA code is doing.
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Re:PSPTool Is a Swiss Army Knife for the Firmware of the AMD... by pgeorgi on Thursday June 06, 2019 @06:37AM (#20113187)
Before Zen, yes. Since Zen, that's in PSP, presumably for the PSP's various other features.
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