[PATCH] ARM: dts: imx7s: Pass the 'fsl,sec-era' property

[shawnguo@kernel.org (Shawn Guo)]

On Fri, May 04, 2018 at 01:31:52PM -0300, Fabio Estevam wrote:
> Hi Shawn,
> 
> On Fri, May 4, 2018 at 4:19 AM, Shawn Guo <shawnguo@kernel.org> wrote:
> 
> > The property is documented as optional in the bindings.  Missing the
> > property shouldn't cause any fatal error, I guess.
> 
> The CAAM drivers uses the era information in many places:
> 
> drivers/crypto/caam/caamalg.c:  if (ctrlpriv->era >= 6) {
> drivers/crypto/caam/caamalg.c:  if (ctrlpriv->era < 3)
> drivers/crypto/caam/caamalg.c:  if (priv->era >= 6 && uses_dkp)
> drivers/crypto/caam/caamalg_desc.c:     if (era < 6) {
> drivers/crypto/caam/caamalg_desc.c:     /* Class 2 operation */
> drivers/crypto/caam/caamalg_desc.c:     if (era < 6) {
> drivers/crypto/caam/caamalg_desc.c:     /* Class 2 operation */
> drivers/crypto/caam/caamalg_desc.c:     if (era < 6) {
> 
> If the era information is not provided the value of -524 (-ENOTSUPP)
> will be used, so all the above logic will not operate correctly.
> 
> I have sent a patch that allows the era information to be retrieved
> via CAAM registers:
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/crypto/caam/ctrl.c?h=next-20180424&id=654f2b937b389295581bcb4aa26011a63db7bc8f
> 
> but this will only land in 4.18.
> 
> In order to avoid i.MX7 to report the incorrect era information in
> 4.17 I suggest that this patch should be applied for 4.17-rc.

I applied it for 4.17, but still questioning whether it's reasonable to
have the property documented as optional in bindings, if missing the
property results in a non-functional driver.

Shawn