We have run into an interesting problem with the PCD database when the PEI and DXE databases were not built at the same time. This happens with boot-block type arrangements. This is not a Dynamic vs. DynamicEx issue.
Short form: 1) The standard PCD database for Dynamic/DynamicEx PCDs is broken into two pieces, based on whether the PCD is access by a PEIM, a DXE driver, or both. The pieces are embedded directly into the PCD PEIM and PCD DXE driver that produces the PCD services. 2) Each Dynamic/DynamicEx PCD is assigned a unique "local token number" This number is different than the token number which is in the PCD declaration in the .dec file. This number is assigned at build time. 3) If a later version of the DXE PCD driver is a) built in a later codebase where there are more or less PEI-access PCDs, but later b) executed with a version of the PEI PCD database from the earlier codebase where there were fewer, it causes a problem. For example, if the new PEI PCD database has 4 more, the new DXE PCD database will start its numbering at +4. But when it is executed with the old PEI PCD database, it will end up looking up the wrong PCD We're not sure what the best course is to solve this. Frankly, the PCD database format is a muddle. We have a temporary work-around, but we're wondering if anyone has thoughts on a good solution. Thanks, Tim _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
