Am 2022-05-11 12:28, schrieb Horia Geantă:
For non-E variants, it might happen that Blob protocol is enabled,
but
number of AES CHA are zero.
If the output of below expression is > 0, then only blob_present
should be marked present or true.
For era > 10, you handled. But for era < 10, please add the below
code.
Are there any CAAMs which can be just enabled partially for era <
10?
I didn't found anything. To me it looks like the non-export
controlled
CAAM is only available for era >= 10. For era < 10, the CAAM is
either
fully featured there or it is not available at all and thus the node
is removed in the bootloader (at least that is the case for
layerscape).
Qouting from our previous discussion in U-boot:
https://patchwork.ozlabs.org/project/uboot/patch/20200602150904.1997-1-michael@xxxxxxxx/#2457448
"
Based on previous (NXP-internal) discussions, non-E crypto module is:
-fully disabled on: LS1021A (ARMv7), LS1043A, LS1088A, LS2088A
(and their personalities)
-partially [*] disabled on: LS1012A, LS1028A, LS1046A, LX2160A
(and their personalities)
"
From the partially disabled list, LS1028A and LX2160A have CAAM Era
10,
while LS1012A and LS1046A integrate CAAM Era 8.
Thanks for clarification. Do you know it that is a layerscape feature?
I had a look at the imx8mn which have a era 9 and it doesn't have the
PKHA_VERSION register which indicates the partially disabled PKHA
block. Thus I concluded that there is no partially disabled feature
on era < 10.
Unfortunately when moving from Era 9 to Era 10, the register map
is not 100% backwards-compatible.
This is why you're not seeing PKHA_VERSION register for i.MX8MN.
For Era >= 10, the CHA version and CHA number fields are conveniently
found
found in the same *_VERSION register, e.g. PKHA_VID and PKHA_NUM are
both
located in PKHA_VERSION.
For Era < 10, these fields are scattered:
CHAVID_LS[PKVID]
CHANUM_LS[PKNUM]
Ok, but there is only the number of instances. I couldn't find a
similar bit to the PKHA_VERSION[PKHA_MISC[7]] bit, which indicates
PKHA decryption/encryption capability is disabled. That seems to
be only for era >= 10, right? That was what caused my confusion,
because until now I was under the impression that non-E variants
will always have that bit.
Rereading your comment, you don't mention PKHA at all. So for
era <10 if you blow the EXPORT_CONTROL fuse, you'll have zero
in any *NUM except for MDNUM, RNGNUM and CRCNUM. Is that correct?
In that case, I agree, we should also check CHANUM_LS[AESNUM] for
era < 10.
-michael
