[3/3] arm64: dts: renesas: r8a7795: add ccree binding

Message ID 1526387370-17142-4-git-send-email-gilad@benyossef.com
State New
Headers show
Series
  • [1/3] crypto: ccree: drop signature register check
Related show

Commit Message

Gilad Ben-Yossef May 15, 2018, 12:29 p.m.
Add bindings for CryptoCell instance in the SoC.

Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>

---
 arch/arm64/boot/dts/renesas/r8a7795.dtsi | 8 ++++++++
 1 file changed, 8 insertions(+)

-- 
2.7.4

Comments

Simon Horman May 16, 2018, 7:43 a.m. | #1
On Tue, May 15, 2018 at 04:50:44PM +0200, Geert Uytterhoeven wrote:
> Hi Gilad,

> 

> On Tue, May 15, 2018 at 2:29 PM, Gilad Ben-Yossef <gilad@benyossef.com> wrote:

> > Add bindings for CryptoCell instance in the SoC.

> >

> > Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>

> 

> Thanks for your patch!

> 

> > --- a/arch/arm64/boot/dts/renesas/r8a7795.dtsi

> > +++ b/arch/arm64/boot/dts/renesas/r8a7795.dtsi

> > @@ -528,6 +528,14 @@

> >                         status = "disabled";

> >                 };

> >

> > +               arm_cc630p: crypto@e6601000 {

> > +                       compatible = "arm,cryptocell-630p-ree";

> > +                       interrupts = <GIC_SPI 71 IRQ_TYPE_LEVEL_HIGH>;

> > +                       #interrupt-cells = <2>;

> 

> I believe the #interrupt-cells property is not needed.

> 

> > +                       reg = <0x0 0xe6601000 0 0x1000>;

> > +                       clocks = <&cpg CPG_MOD 229>;

> > +               };

> 

> The rest looks good, but I cannot verify the register block.

> 

> > +

> >                 i2c3: i2c@e66d0000 {

> >                         #address-cells = <1>;

> >                         #size-cells = <0>;


Thanks, I have applied this after dropping the #interrupt-cells property.
Simon Horman May 17, 2018, 9:04 a.m. | #2
On Thu, May 17, 2018 at 11:01:57AM +0300, Gilad Ben-Yossef wrote:
> On Wed, May 16, 2018 at 10:43 AM, Simon Horman <horms@verge.net.au> wrote:

> > On Tue, May 15, 2018 at 04:50:44PM +0200, Geert Uytterhoeven wrote:

> >> Hi Gilad,

> >>

> >> On Tue, May 15, 2018 at 2:29 PM, Gilad Ben-Yossef <gilad@benyossef.com> wrote:

> >> > Add bindings for CryptoCell instance in the SoC.

> >> >

> >> > Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>

> >>

> >> Thanks for your patch!

> >>

> >> > --- a/arch/arm64/boot/dts/renesas/r8a7795.dtsi

> >> > +++ b/arch/arm64/boot/dts/renesas/r8a7795.dtsi

> >> > @@ -528,6 +528,14 @@

> >> >                         status = "disabled";

> >> >                 };

> >> >

> >> > +               arm_cc630p: crypto@e6601000 {

> >> > +                       compatible = "arm,cryptocell-630p-ree";

> >> > +                       interrupts = <GIC_SPI 71 IRQ_TYPE_LEVEL_HIGH>;

> >> > +                       #interrupt-cells = <2>;

> >>

> >> I believe the #interrupt-cells property is not needed.

> >>

> >> > +                       reg = <0x0 0xe6601000 0 0x1000>;

> >> > +                       clocks = <&cpg CPG_MOD 229>;

> >> > +               };

> >>

> >> The rest looks good, but I cannot verify the register block.

> >>

> >> > +

> >> >                 i2c3: i2c@e66d0000 {

> >> >                         #address-cells = <1>;

> >> >                         #size-cells = <0>;

> >

> > Thanks, I have applied this after dropping the #interrupt-cells property.

> 

> Thanks you!

> 

> Alas, it will not work without the clk patch (the previous one in the

> series) so they need to be

> taken or dropped together.


I think its fine if it does not yet work.
But not if its causes things that previously worked to stop working.
Gilad Ben-Yossef May 17, 2018, 1:09 p.m. | #3
On Thu, May 17, 2018 at 1:16 PM, Geert Uytterhoeven
<geert@linux-m68k.org> wrote:
> Hi Gilad,

>

> On Thu, May 17, 2018 at 10:01 AM, Gilad Ben-Yossef <gilad@benyossef.com> wrote:

>> On Wed, May 16, 2018 at 10:43 AM, Simon Horman <horms@verge.net.au> wrote:

>>> On Tue, May 15, 2018 at 04:50:44PM +0200, Geert Uytterhoeven wrote:

>>>> On Tue, May 15, 2018 at 2:29 PM, Gilad Ben-Yossef <gilad@benyossef.com> wrote:

>>>> > Add bindings for CryptoCell instance in the SoC.

>>>> >

>>>> > Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>

>>>>

>>>> Thanks for your patch!

>>>>

>>>> > --- a/arch/arm64/boot/dts/renesas/r8a7795.dtsi

>>>> > +++ b/arch/arm64/boot/dts/renesas/r8a7795.dtsi

>>>> > @@ -528,6 +528,14 @@

>>>> >                         status = "disabled";

>>>> >                 };

>>>> >

>>>> > +               arm_cc630p: crypto@e6601000 {

>>>> > +                       compatible = "arm,cryptocell-630p-ree";

>>>> > +                       interrupts = <GIC_SPI 71 IRQ_TYPE_LEVEL_HIGH>;

>>>> > +                       #interrupt-cells = <2>;

>>>>

>>>> I believe the #interrupt-cells property is not needed.

>>>>

>>>> > +                       reg = <0x0 0xe6601000 0 0x1000>;

>>>> > +                       clocks = <&cpg CPG_MOD 229>;

>

> Missing "power-domains = <&sysc R8A7795_PD_ALWAYS_ON>;", as

> the Secure Engine is part of the CPG/MSSR clock domain (see below [*]).


Thank you. I didn't get this information from Renesas :-)

>

>>>> > +               };

>>>>

>>>> The rest looks good, but I cannot verify the register block.

>>>>

>>>> > +

>>>> >                 i2c3: i2c@e66d0000 {

>>>> >                         #address-cells = <1>;

>>>> >                         #size-cells = <0>;

>>>

>>> Thanks, I have applied this after dropping the #interrupt-cells property.

>>

>> Thanks you!

>>

>> Alas, it will not work without the clk patch (the previous one in the

>> series) so they need to be

>> taken or dropped together.

>

> Indeed. From a quick glance, it looks like drivers/crypto/ccree/cc_driver.c

> does not distinguish between the absence of the clock property, and an

> actual error in getting the clock, and never considers any error a failure

> (incl. -PROBE_DEFER).

>

> As of_clk_get() returns -ENOENT for both a missing clock property and a

> missing clock, you should use (devm_)clk_get() instead, and distinguish

> between NULL (no clock property) and IS_ERR() (actual failure -> abort).

>


Thank you, this is very valuable. I will do as you suggested.


> Hence in the absence of the clock patch, the driver accesses the crypto

> engine while its module clock is turned off, leading to:

>

>     ccree e6601000.crypto: Invalid CC signature: SIGNATURE=0x00000000

> != expected=0xDCC63000

>

> You must be lucky, though, usually you get an imprecise external abort

> later, crashing the whole system ;-)

>

> So I think this patch should be dropped for now.

>

> However, even with your clock patch, the signature checking fails for me,

> on both R-Car H3 ES1.0 and ES2.0.

> Does this need changes to the ARM Trusted Firmware, to allow Linux to

> access the public SCEG module?


Well, this is actually something different. If you look you will
notice that my patch was part of a 3 part patch series,
the first of which disabled this test.

If you take all the 3 patches, it will work.

To make things more interesting, I have since sending the patch
learned WHY the test does not work, so disabling
it is not needed - to make a long story short, I was reading the wrong
register that just happens to have the right value
in our FPGA based tests systems but does not in the real silicon
implementations.

But you are right - if the clock is not enabled and you are try to
read from the register the system does freeze.

I will send a fixed v2. based on your patch enabling the CR clock.

>

> [*] More on the subject of clock control:

> At least for Renesas SoCs, where the module is part of a clock domain, and

> can be controlled automatically by Runtime PM, you could drop the explicit

> clock control, and use Runtime PM instead

> (pm_runtime_{enable,get_sync,put,disable}()).  That would allow the driver

> to work on systems with any kind of PM Domains, too.

> Depending on the other platforms that include a CryptoCell and their

> (non)reliance on PM Domains, you may have to keep the explicit clock

> handling, in addition to Runtime PM.

>




> To decrease power consumption, I suggest to move the clock and/or Runtime

> PM handling to the routines that actually use the hardware, instead of

> powering the module in the probe routine.

>


This is very interesting and I will give it a try.

Thanks again!
Gilad



-- 
Gilad Ben-Yossef
Chief Coffee Drinker

"If you take a class in large-scale robotics, can you end up in a
situation where the homework eats your dog?"
 -- Jean-Baptiste Queru
Geert Uytterhoeven May 17, 2018, 1:49 p.m. | #4
Hi Gilad,

On Thu, May 17, 2018 at 3:41 PM, Gilad Ben-Yossef <gilad@benyossef.com> wrote:
> On Thu, May 17, 2018 at 4:35 PM, Geert Uytterhoeven

> <geert@linux-m68k.org> wrote:

>> On Thu, May 17, 2018 at 3:09 PM, Gilad Ben-Yossef <gilad@benyossef.com> wrote:

>>> On Thu, May 17, 2018 at 1:16 PM, Geert Uytterhoeven

>>> <geert@linux-m68k.org> wrote:

>>>> However, even with your clock patch, the signature checking fails for me,

>>>> on both R-Car H3 ES1.0 and ES2.0.

>>>> Does this need changes to the ARM Trusted Firmware, to allow Linux to

>>>> access the public SCEG module?

>>>

>>> Well, this is actually something different. If you look you will

>>> notice that my patch was part of a 3 part patch series,

>>> the first of which disabled this test.

>>

>> Sorry, I had completely forgotten about the first patch from the series.

>> With that applied, it continues:

>>

>>         ccree e6601000.crypto: ARM CryptoCell 630P Driver: HW version

>> 0x00000000, Driver version 4.0

>>         ccree e6601000.crypto: Cache params previous: 0x00000777

>>         ccree e6601000.crypto: Cache params current: 0x00000000

>> (expect: 0x00000000)

>>         alg: No test for cts1(cbc(aes)) (cts1-cbc-aes-ccree)

>>         alg: No test for authenc(xcbc(aes),cbc(aes))

>> (authenc-xcbc-aes-cbc-aes-ccree)

>>         alg: No test for authenc(xcbc(aes),rfc3686(ctr(aes)))

>> (authenc-xcbc-aes-rfc3686-ctr-aes-ccree)

>>         ccree e6601000.crypto: ARM ccree device initialized

>>

>> Is HW version 0x00000000 expected?

>

> It's related to the problem with reading the wrong register I've

> mentioned before.


OK.

>>> If you take all the 3 patches, it will work.

>>

>> is there an easy way to test proper operation?

>

> The lines of the form "  alg: No test for cts1(cbc(aes))

> (cts1-cbc-aes-ccree)" indicates

> you have the Crypto API testmgr enable (or rather not disabled would

> be more accurate) so every

> cryptographic algorithm except those specified in these messages was

> tested with test

> vectors from crypto/testmgr.c upon registration. If you don't seen

> failure warnings, it works.


OK.

> You can also check /proc/crypto for all the algorithm with ccree

> listed as their driver and check

> that their test passed.


OK, in that case everything works as expected, on both R-Car H3 ES1.0 and
ES2.0.

Thanks!

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
Simon Horman May 18, 2018, 9:50 a.m. | #5
On Thu, May 17, 2018 at 04:12:23PM +0300, Gilad Ben-Yossef wrote:
> On Thu, May 17, 2018 at 12:04 PM, Simon Horman <horms@verge.net.au> wrote:

> > On Thu, May 17, 2018 at 11:01:57AM +0300, Gilad Ben-Yossef wrote:

> >> On Wed, May 16, 2018 at 10:43 AM, Simon Horman <horms@verge.net.au> wrote:

> >> > On Tue, May 15, 2018 at 04:50:44PM +0200, Geert Uytterhoeven wrote:

> >> >> Hi Gilad,

> >> >>

> >> >> On Tue, May 15, 2018 at 2:29 PM, Gilad Ben-Yossef <gilad@benyossef.com> wrote:

> >> >> > Add bindings for CryptoCell instance in the SoC.

> >> >> >

> >> >> > Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>

> >> >>

> >> >> Thanks for your patch!

> >> >>

> >> >> > --- a/arch/arm64/boot/dts/renesas/r8a7795.dtsi

> >> >> > +++ b/arch/arm64/boot/dts/renesas/r8a7795.dtsi

> >> >> > @@ -528,6 +528,14 @@

> >> >> >                         status = "disabled";

> >> >> >                 };

> >> >> >

> >> >> > +               arm_cc630p: crypto@e6601000 {

> >> >> > +                       compatible = "arm,cryptocell-630p-ree";

> >> >> > +                       interrupts = <GIC_SPI 71 IRQ_TYPE_LEVEL_HIGH>;

> >> >> > +                       #interrupt-cells = <2>;

> >> >>

> >> >> I believe the #interrupt-cells property is not needed.

> >> >>

> >> >> > +                       reg = <0x0 0xe6601000 0 0x1000>;

> >> >> > +                       clocks = <&cpg CPG_MOD 229>;

> >> >> > +               };

> >> >>

> >> >> The rest looks good, but I cannot verify the register block.

> >> >>

> >> >> > +

> >> >> >                 i2c3: i2c@e66d0000 {

> >> >> >                         #address-cells = <1>;

> >> >> >                         #size-cells = <0>;

> >> >

> >> > Thanks, I have applied this after dropping the #interrupt-cells property.

> >>

> >> Thanks you!

> >>

> >> Alas, it will not work without the clk patch (the previous one in the

> >> series) so they need to be

> >> taken or dropped together.

> >

> > I think its fine if it does not yet work.

> > But not if its causes things that previously worked to stop working.

> 

> Based on the further discussion with Geert my recommendation is to

> drop my patch for now,

> take Geert CR clock  patch and I will follow up next week with a v2

> that fixes the clock

> handing as discussed with Geert.


Thanks, I will drop the patch.
Gilad Ben-Yossef May 24, 2018, 1:20 p.m. | #6
On Tue, May 22, 2018 at 10:48 AM, Geert Uytterhoeven
<geert@linux-m68k.org> wrote:
> Hi Gilad,

>

> On Mon, May 21, 2018 at 3:43 PM, Gilad Ben-Yossef <gilad@benyossef.com> wrote:

>> On Thu, May 17, 2018 at 1:16 PM, Geert Uytterhoeven

>> <geert@linux-m68k.org> wrote:

>>> Indeed. From a quick glance, it looks like drivers/crypto/ccree/cc_driver.c

>>> does not distinguish between the absence of the clock property, and an

>>> actual error in getting the clock, and never considers any error a failure

>>> (incl. -PROBE_DEFER).

>>>

>>> As of_clk_get() returns -ENOENT for both a missing clock property and a

>>> missing clock, you should use (devm_)clk_get() instead, and distinguish

>>> between NULL (no clock property) and IS_ERR() (actual failure -> abort).

>>

>> I was trying to do as you suggested but I didn't quite get what is the

>> dev_id (2nd) parameter to devm_clk_get parameter is supposed to be.

>

> It's the (optional) name of the clock, helpful in case there is more than one.

> In your case, NULL is fine.

>


I have assumed as much and tried it, it did not work and so I assumed
I am missing something and asked you.
It turns out I was missing the fact I was using the wrong device tree
file... :-(

So thanks, it works now :-)

Having said that, while using devm)clk_get() is a better approach, it
does not seems to distinguish
between no "clocks" and a failure to clock information - it returns
ENOENT in both cases as well.

Thanks,
Gilad


-- 
Gilad Ben-Yossef
Chief Coffee Drinker

"If you take a class in large-scale robotics, can you end up in a
situation where the homework eats your dog?"
 -- Jean-Baptiste Queru

Patch

diff --git a/arch/arm64/boot/dts/renesas/r8a7795.dtsi b/arch/arm64/boot/dts/renesas/r8a7795.dtsi
index 91486b4..6c76841 100644
--- a/arch/arm64/boot/dts/renesas/r8a7795.dtsi
+++ b/arch/arm64/boot/dts/renesas/r8a7795.dtsi
@@ -528,6 +528,14 @@ 
 			status = "disabled";
 		};
 
+		arm_cc630p: crypto@e6601000 {
+			compatible = "arm,cryptocell-630p-ree";
+			interrupts = <GIC_SPI 71 IRQ_TYPE_LEVEL_HIGH>;
+			#interrupt-cells = <2>;
+			reg = <0x0 0xe6601000 0 0x1000>;
+			clocks = <&cpg CPG_MOD 229>;
+		};
+
 		i2c3: i2c@e66d0000 {
 			#address-cells = <1>;
 			#size-cells = <0>;