ot_otp: Add scrambling on DAI writes to secret partitions + REGWEN fixes
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ot_otp: Add scrambling on DAI writes to secret partitions + check REGWENsot_otp: Add scrambling on DAI writes to secret partitions + REGWEN fixes
rivos-eblot
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The actual check registers remain unimplemented, but the REGWENs surrounding them are now properly implemented and writable. Also corrects the access types of some of the associated registers. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
The actual check registers remain unimplemented, but the REGWENs surrounding them are now properly implemented and writable. Also corrects the access types of some of the associated registers. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
Introduce scrambling to DAI writes of secret partitions, which should always be a 64-bit granularity. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
Introduce scrambling to DAI writes of secret partitions, which should always be a 64-bit granularity. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
This regwen is not read-only - SW can write a 0 to clear it and lock the DAI interface. The REGWEN should still be locked when the DAI is non-idle, but now it has a permanent software lock which is only resolved by a reset of the `otp_ctrl`. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
This regwen is not read-only - SW can write a 0 to clear it and lock the DAI interface. The REGWEN should still be locked when the DAI is non-idle, but now it has a permanent software lock which is only resolved by a reset of the `otp_ctrl`. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
This test is now passing with the otp_ctrl REGWENs being emulated. Also add a couple extra passing tests that have not yet been marked as such (`otp_ctrl_descrambling_test` and `usbdev_vbus_test`). Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
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While we have scrambling on reads from secret partitions, to properly support provisioning flows we will need to be able to scramble when programming these secret partitions via DAI writes. Add support for these to both Earlgrey and Darjeeling.
As part of testing this, I also found that the two check REGWEN registers were unimplemented, which were being checked by some SW test utilities. While the check functionality is still unimplemented, writes/reads of these REGWENs are now implemented in both Earlgrey and Darjeeling, and the access permissions of some of these registers are fixed. This should be sufficient now to support the
lc_ctrl_otp_hw_cfg0_test, as well as theotp_ctrl_smoketestwhen QEMU is enabled for that test upstream.There was no nice existing test for this feature in OpenTitan except in DV environments, so I threw together something to quickly test it on an Opentitan branch here, constructing an OTP image and removing some irrelevant keymgr checks from the DV test. This is sufficient to check that we can write a value to the SECRET2 partition (which is scrambled), and read it back and get the same value.
Edit: the third change to fix
DIRECT_ACCESS_REGWENis another small bug fix while I'm in the area which should be enough to getotp_ctrl_mem_access_testpassing when QEMU support is added for this in OpenTitan.