Hi,

Am 2022-05-11 11:16, schrieb Pankaj Gupta:

quoted

-----Original Message-----
From: Ahmad Fatoum <a.fatoum@pengutronix.de>
Sent: Monday, May 9, 2022 6:34 PM
To: Pankaj Gupta <pankaj.gupta@nxp.com>; Horia Geanta
[off-list ref]; Herbert Xu [off-list ref]; 
David S.
Miller [off-list ref]
Cc: kernel@pengutronix.de; Michael Walle <redacted>; James
Bottomley [off-list ref]; Jarkko Sakkinen [off-list ref]; 
Mimi
Zohar [off-list ref]; David Howells [off-list ref]; 
James
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E.
Hallyn [off-list ref]; Jan Luebbe [off-list ref]; David 
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Lenormand [off-list ref]; Matthias Schiffer
[off-list ref]; Sumit Garg 
[off-list ref];
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Subject: Re: [EXT] [PATCH v9 3/7] crypto: caam - determine whether 
CAAM
supports blob encap/decap

Caution: EXT Email

Hello Pankaj,

On Mon, 2022-05-09 at 12:39 +0000, Pankaj Gupta wrote:

quoted

quoted

-       if (ctrlpriv->era < 10)
+       comp_params = rd_reg32(&ctrl->perfmon.comp_parms_ls);
+       ctrlpriv->blob_present = !!(comp_params & CTPR_LS_BLOB);
+
+       if (ctrlpriv->era < 10) {
                rng_vid = (rd_reg32(&ctrl->perfmon.cha_id_ls) &
                           CHA_ID_LS_RNG_MASK) >>
CHA_ID_LS_RNG_SHIFT;

Check for AES CHAs for Era < 10, should be added.

Do I need this? I only do this check for Era >= 10, because apparently 
there are
Layerscape non-E processors that indicate BLOB support via 
CTPR_LS_BLOB, but
fail at runtime. Are there any Era < 10 SoCs that are similarly 
broken?

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).

-michael