[ot] hw/opentitan: ot_clkmgr, ot_spi_host: Earlgrey 1.0.0 backwards compatability #148
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Earlgrey 1.0.0 uses SPI Host V2, not V3, which has breaking changes to the size and locations of the field in the SPI Host command register. This can just be adapted by changing the field definitions; the command length in earlgrey-1.0.0 is smaller and so the rest of the code is backwards-compatible. For the clkmgr, there was a known RTL bug in 1.0.0 where the jitter enable register was not actually protected by its respective REGWEN register. This replicates that behaviour for correct testing on the earlgrey-1.0.0 branch. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
jwnrt
approved these changes
Feb 26, 2025
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This PR is to a new branch intended to maintain temporary backwards compatibility with the
earlgrey-1.0.0target. This includes reverting HW changes to the QEMU model since that branch was taken (including the SPI Host changes), and replicating RTL bugs present in that version (e.g. the clkmgr bug in this PR).This branch is intended to likely be a temporary workaround: it would be nice to have a better solution for supporting different tops in QEMU, where
earlgrey-1.0.0could just be a slightly modified top from Earlgrey master, but since we have need for this now we just manually ad this with some conditional#ifdefs.