[PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Marek Vasut]

Linux 6.6.y with KASLR enabled would print the following message on boot:
"
KASLR disabled due to lack of seed
"
Enable the 'kaslrseed' command so a random number seed can be pulled
from CAAM and inserted into the /chosen node 'kaslr-seed' property of
Linux kernel DT before boot, thus letting KASLR work properly.

Signed-off-by: Marek Vasut <marex@denx.de>
---
Cc: Fabio Estevam <festevam@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
Cc: u-boot@dh-electronics.com
---
 configs/imx8mp_dhcom_pdk2_defconfig | 2 ++
 configs/imx8mp_dhcom_pdk3_defconfig | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/configs/imx8mp_dhcom_pdk2_defconfig b/configs/imx8mp_dhcom_pdk2_defconfig
index 4f907ce00d0..23fb6272ad5 100644
--- a/configs/imx8mp_dhcom_pdk2_defconfig
+++ b/configs/imx8mp_dhcom_pdk2_defconfig
@@ -117,6 +117,7 @@ CONFIG_CMD_BOOTCOUNT=y
 CONFIG_CMD_CACHE=y
 CONFIG_CMD_TIME=y
 CONFIG_CMD_GETTIME=y
+CONFIG_CMD_KASLRSEED=y
 CONFIG_CMD_SYSBOOT=y
 CONFIG_CMD_UUID=y
 CONFIG_CMD_PMIC=y
@@ -223,6 +224,7 @@ CONFIG_DM_REGULATOR_PCA9450=y
 CONFIG_SPL_DM_REGULATOR_PCA9450=y
 CONFIG_DM_REGULATOR_FIXED=y
 CONFIG_DM_REGULATOR_GPIO=y
+CONFIG_DM_RNG=y
 CONFIG_DM_RTC=y
 CONFIG_RTC_M41T62=y
 CONFIG_CONS_INDEX=2
diff --git a/configs/imx8mp_dhcom_pdk3_defconfig b/configs/imx8mp_dhcom_pdk3_defconfig
index 9972e2d96b6..0d47c12b1f9 100644
--- a/configs/imx8mp_dhcom_pdk3_defconfig
+++ b/configs/imx8mp_dhcom_pdk3_defconfig
@@ -119,6 +119,7 @@ CONFIG_CMD_BOOTCOUNT=y
 CONFIG_CMD_CACHE=y
 CONFIG_CMD_TIME=y
 CONFIG_CMD_GETTIME=y
+CONFIG_CMD_KASLRSEED=y
 CONFIG_CMD_SYSBOOT=y
 CONFIG_CMD_UUID=y
 CONFIG_CMD_PMIC=y
@@ -228,6 +229,7 @@ CONFIG_DM_REGULATOR_PCA9450=y
 CONFIG_SPL_DM_REGULATOR_PCA9450=y
 CONFIG_DM_REGULATOR_FIXED=y
 CONFIG_DM_REGULATOR_GPIO=y
+CONFIG_DM_RNG=y
 CONFIG_DM_RTC=y
 CONFIG_RTC_M41T62=y
 CONFIG_CONS_INDEX=2
-- 
2.43.0

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Fabio Estevam]

On Fri, Jan 19, 2024 at 9:36 PM Marek Vasut <marex@denx.de> wrote:
>
> Linux 6.6.y with KASLR enabled would print the following message on boot:
> "
> KASLR disabled due to lack of seed
> "
> Enable the 'kaslrseed' command so a random number seed can be pulled
> from CAAM and inserted into the /chosen node 'kaslr-seed' property of
> Linux kernel DT before boot, thus letting KASLR work properly.
>
> Signed-off-by: Marek Vasut <marex@denx.de>

Reviewed-by: Fabio Estevam <festevam@denx.de>

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Fabio Estevam]

On Fri, Jan 19, 2024 at 9:36 PM Marek Vasut <marex@denx.de> wrote:
>
> Linux 6.6.y with KASLR enabled would print the following message on boot:
> "
> KASLR disabled due to lack of seed
> "
> Enable the 'kaslrseed' command so a random number seed can be pulled
> from CAAM and inserted into the /chosen node 'kaslr-seed' property of
> Linux kernel DT before boot, thus letting KASLR work properly.
>
> Signed-off-by: Marek Vasut <marex@denx.de>

Applied, thanks.

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Fabio Estevam]

On Fri, Jan 19, 2024 at 9:36 PM Marek Vasut <marex@denx.de> wrote:
>
> Linux 6.6.y with KASLR enabled would print the following message on boot:
> "
> KASLR disabled due to lack of seed
> "
> Enable the 'kaslrseed' command so a random number seed can be pulled
> from CAAM and inserted into the /chosen node 'kaslr-seed' property of
> Linux kernel DT before boot, thus letting KASLR work properly.
>
> Signed-off-by: Marek Vasut <marex@denx.de>

Applied, thanks.

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Tim Harvey]

On Fri, Jan 19, 2024 at 4:36 PM Marek Vasut <marex@denx.de> wrote:
>
> Linux 6.6.y with KASLR enabled would print the following message on boot:
> "
> KASLR disabled due to lack of seed
> "
> Enable the 'kaslrseed' command so a random number seed can be pulled
> from CAAM and inserted into the /chosen node 'kaslr-seed' property of
> Linux kernel DT before boot, thus letting KASLR work properly.
>
> Signed-off-by: Marek Vasut <marex@denx.de>
> ---
> Cc: Fabio Estevam <festevam@denx.de>
> Cc: Stefano Babic <sbabic@denx.de>
> Cc: u-boot@dh-electronics.com
> ---
>  configs/imx8mp_dhcom_pdk2_defconfig | 2 ++
>  configs/imx8mp_dhcom_pdk3_defconfig | 2 ++
>  2 files changed, 4 insertions(+)
>
> diff --git a/configs/imx8mp_dhcom_pdk2_defconfig b/configs/imx8mp_dhcom_pdk2_defconfig
> index 4f907ce00d0..23fb6272ad5 100644
> --- a/configs/imx8mp_dhcom_pdk2_defconfig
> +++ b/configs/imx8mp_dhcom_pdk2_defconfig
> @@ -117,6 +117,7 @@ CONFIG_CMD_BOOTCOUNT=y
>  CONFIG_CMD_CACHE=y
>  CONFIG_CMD_TIME=y
>  CONFIG_CMD_GETTIME=y
> +CONFIG_CMD_KASLRSEED=y
>  CONFIG_CMD_SYSBOOT=y
>  CONFIG_CMD_UUID=y
>  CONFIG_CMD_PMIC=y
> @@ -223,6 +224,7 @@ CONFIG_DM_REGULATOR_PCA9450=y
>  CONFIG_SPL_DM_REGULATOR_PCA9450=y
>  CONFIG_DM_REGULATOR_FIXED=y
>  CONFIG_DM_REGULATOR_GPIO=y
> +CONFIG_DM_RNG=y
>  CONFIG_DM_RTC=y
>  CONFIG_RTC_M41T62=y
>  CONFIG_CONS_INDEX=2
> diff --git a/configs/imx8mp_dhcom_pdk3_defconfig b/configs/imx8mp_dhcom_pdk3_defconfig
> index 9972e2d96b6..0d47c12b1f9 100644
> --- a/configs/imx8mp_dhcom_pdk3_defconfig
> +++ b/configs/imx8mp_dhcom_pdk3_defconfig
> @@ -119,6 +119,7 @@ CONFIG_CMD_BOOTCOUNT=y
>  CONFIG_CMD_CACHE=y
>  CONFIG_CMD_TIME=y
>  CONFIG_CMD_GETTIME=y
> +CONFIG_CMD_KASLRSEED=y
>  CONFIG_CMD_SYSBOOT=y
>  CONFIG_CMD_UUID=y
>  CONFIG_CMD_PMIC=y
> @@ -228,6 +229,7 @@ CONFIG_DM_REGULATOR_PCA9450=y
>  CONFIG_SPL_DM_REGULATOR_PCA9450=y
>  CONFIG_DM_REGULATOR_FIXED=y
>  CONFIG_DM_REGULATOR_GPIO=y
> +CONFIG_DM_RNG=y
>  CONFIG_DM_RTC=y
>  CONFIG_RTC_M41T62=y
>  CONFIG_CONS_INDEX=2
> --
> 2.43.0
>

Hi Marek,

Sorry to respond to an old thread but I ran across this when enabling
KALSR on my boards.

I have noticed when you enable DM_RNG on IMX8M that SPL fails to bind
the driver:
Couldn't bind rng driver (-96)
SEC0:  RNG instantiated

sec_init failed!

Didn't you encounter this as well? It seems to me that we may need to
add the ability to disable DM_RNG in the SPL unless I'm missing
something.

Best Regards,

Tim

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Marek Vasut]

On 4/18/24 6:21 PM, Tim Harvey wrote:
> On Fri, Jan 19, 2024 at 4:36 PM Marek Vasut <marex@denx.de> wrote:
>>
>> Linux 6.6.y with KASLR enabled would print the following message on boot:
>> "
>> KASLR disabled due to lack of seed
>> "
>> Enable the 'kaslrseed' command so a random number seed can be pulled
>> from CAAM and inserted into the /chosen node 'kaslr-seed' property of
>> Linux kernel DT before boot, thus letting KASLR work properly.
>>
>> Signed-off-by: Marek Vasut <marex@denx.de>
>> ---
>> Cc: Fabio Estevam <festevam@denx.de>
>> Cc: Stefano Babic <sbabic@denx.de>
>> Cc: u-boot@dh-electronics.com
>> ---
>>   configs/imx8mp_dhcom_pdk2_defconfig | 2 ++
>>   configs/imx8mp_dhcom_pdk3_defconfig | 2 ++
>>   2 files changed, 4 insertions(+)
>>
>> diff --git a/configs/imx8mp_dhcom_pdk2_defconfig b/configs/imx8mp_dhcom_pdk2_defconfig
>> index 4f907ce00d0..23fb6272ad5 100644
>> --- a/configs/imx8mp_dhcom_pdk2_defconfig
>> +++ b/configs/imx8mp_dhcom_pdk2_defconfig
>> @@ -117,6 +117,7 @@ CONFIG_CMD_BOOTCOUNT=y
>>   CONFIG_CMD_CACHE=y
>>   CONFIG_CMD_TIME=y
>>   CONFIG_CMD_GETTIME=y
>> +CONFIG_CMD_KASLRSEED=y
>>   CONFIG_CMD_SYSBOOT=y
>>   CONFIG_CMD_UUID=y
>>   CONFIG_CMD_PMIC=y
>> @@ -223,6 +224,7 @@ CONFIG_DM_REGULATOR_PCA9450=y
>>   CONFIG_SPL_DM_REGULATOR_PCA9450=y
>>   CONFIG_DM_REGULATOR_FIXED=y
>>   CONFIG_DM_REGULATOR_GPIO=y
>> +CONFIG_DM_RNG=y
>>   CONFIG_DM_RTC=y
>>   CONFIG_RTC_M41T62=y
>>   CONFIG_CONS_INDEX=2
>> diff --git a/configs/imx8mp_dhcom_pdk3_defconfig b/configs/imx8mp_dhcom_pdk3_defconfig
>> index 9972e2d96b6..0d47c12b1f9 100644
>> --- a/configs/imx8mp_dhcom_pdk3_defconfig
>> +++ b/configs/imx8mp_dhcom_pdk3_defconfig
>> @@ -119,6 +119,7 @@ CONFIG_CMD_BOOTCOUNT=y
>>   CONFIG_CMD_CACHE=y
>>   CONFIG_CMD_TIME=y
>>   CONFIG_CMD_GETTIME=y
>> +CONFIG_CMD_KASLRSEED=y
>>   CONFIG_CMD_SYSBOOT=y
>>   CONFIG_CMD_UUID=y
>>   CONFIG_CMD_PMIC=y
>> @@ -228,6 +229,7 @@ CONFIG_DM_REGULATOR_PCA9450=y
>>   CONFIG_SPL_DM_REGULATOR_PCA9450=y
>>   CONFIG_DM_REGULATOR_FIXED=y
>>   CONFIG_DM_REGULATOR_GPIO=y
>> +CONFIG_DM_RNG=y
>>   CONFIG_DM_RTC=y
>>   CONFIG_RTC_M41T62=y
>>   CONFIG_CONS_INDEX=2
>> --
>> 2.43.0
>>
> 
> Hi Marek,
> 
> Sorry to respond to an old thread but I ran across this when enabling
> KALSR on my boards.
> 
> I have noticed when you enable DM_RNG on IMX8M that SPL fails to bind
> the driver:
> Couldn't bind rng driver (-96)
> SEC0:  RNG instantiated
> 
> sec_init failed!

Did you enable CAAM and ARCH_MISC_INIT on your machine, to initialize 
CAAM in SPL ?

> Didn't you encounter this as well? It seems to me that we may need to
> add the ability to disable DM_RNG in the SPL unless I'm missing
> something.

No, but see above, I suspect that might be it, see also

1f908b1898bd ("ARM: imx8m: Deduplicate CAAM init with arch_misc_init() 
call")

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Tim Harvey]

On Thu, Apr 18, 2024 at 10:33 AM Marek Vasut <marex@denx.de> wrote:
>
> On 4/18/24 6:21 PM, Tim Harvey wrote:
> > On Fri, Jan 19, 2024 at 4:36 PM Marek Vasut <marex@denx.de> wrote:
> >>
> >> Linux 6.6.y with KASLR enabled would print the following message on boot:
> >> "
> >> KASLR disabled due to lack of seed
> >> "
> >> Enable the 'kaslrseed' command so a random number seed can be pulled
> >> from CAAM and inserted into the /chosen node 'kaslr-seed' property of
> >> Linux kernel DT before boot, thus letting KASLR work properly.
> >>
> >> Signed-off-by: Marek Vasut <marex@denx.de>
> >> ---
> >> Cc: Fabio Estevam <festevam@denx.de>
> >> Cc: Stefano Babic <sbabic@denx.de>
> >> Cc: u-boot@dh-electronics.com
> >> ---
> >>   configs/imx8mp_dhcom_pdk2_defconfig | 2 ++
> >>   configs/imx8mp_dhcom_pdk3_defconfig | 2 ++
> >>   2 files changed, 4 insertions(+)
> >>
> >> diff --git a/configs/imx8mp_dhcom_pdk2_defconfig b/configs/imx8mp_dhcom_pdk2_defconfig
> >> index 4f907ce00d0..23fb6272ad5 100644
> >> --- a/configs/imx8mp_dhcom_pdk2_defconfig
> >> +++ b/configs/imx8mp_dhcom_pdk2_defconfig
> >> @@ -117,6 +117,7 @@ CONFIG_CMD_BOOTCOUNT=y
> >>   CONFIG_CMD_CACHE=y
> >>   CONFIG_CMD_TIME=y
> >>   CONFIG_CMD_GETTIME=y
> >> +CONFIG_CMD_KASLRSEED=y
> >>   CONFIG_CMD_SYSBOOT=y
> >>   CONFIG_CMD_UUID=y
> >>   CONFIG_CMD_PMIC=y
> >> @@ -223,6 +224,7 @@ CONFIG_DM_REGULATOR_PCA9450=y
> >>   CONFIG_SPL_DM_REGULATOR_PCA9450=y
> >>   CONFIG_DM_REGULATOR_FIXED=y
> >>   CONFIG_DM_REGULATOR_GPIO=y
> >> +CONFIG_DM_RNG=y
> >>   CONFIG_DM_RTC=y
> >>   CONFIG_RTC_M41T62=y
> >>   CONFIG_CONS_INDEX=2
> >> diff --git a/configs/imx8mp_dhcom_pdk3_defconfig b/configs/imx8mp_dhcom_pdk3_defconfig
> >> index 9972e2d96b6..0d47c12b1f9 100644
> >> --- a/configs/imx8mp_dhcom_pdk3_defconfig
> >> +++ b/configs/imx8mp_dhcom_pdk3_defconfig
> >> @@ -119,6 +119,7 @@ CONFIG_CMD_BOOTCOUNT=y
> >>   CONFIG_CMD_CACHE=y
> >>   CONFIG_CMD_TIME=y
> >>   CONFIG_CMD_GETTIME=y
> >> +CONFIG_CMD_KASLRSEED=y
> >>   CONFIG_CMD_SYSBOOT=y
> >>   CONFIG_CMD_UUID=y
> >>   CONFIG_CMD_PMIC=y
> >> @@ -228,6 +229,7 @@ CONFIG_DM_REGULATOR_PCA9450=y
> >>   CONFIG_SPL_DM_REGULATOR_PCA9450=y
> >>   CONFIG_DM_REGULATOR_FIXED=y
> >>   CONFIG_DM_REGULATOR_GPIO=y
> >> +CONFIG_DM_RNG=y
> >>   CONFIG_DM_RTC=y
> >>   CONFIG_RTC_M41T62=y
> >>   CONFIG_CONS_INDEX=2
> >> --
> >> 2.43.0
> >>
> >
> > Hi Marek,
> >
> > Sorry to respond to an old thread but I ran across this when enabling
> > KALSR on my boards.
> >
> > I have noticed when you enable DM_RNG on IMX8M that SPL fails to bind
> > the driver:
> > Couldn't bind rng driver (-96)
> > SEC0:  RNG instantiated
> >
> > sec_init failed!
>
> Did you enable CAAM and ARCH_MISC_INIT on your machine, to initialize
> CAAM in SPL ?

yes

>
> > Didn't you encounter this as well? It seems to me that we may need to
> > add the ability to disable DM_RNG in the SPL unless I'm missing
> > something.
>
> No, but see above, I suspect that might be it, see also
>
> 1f908b1898bd ("ARM: imx8m: Deduplicate CAAM init with arch_misc_init()
> call")

yes, I have that same patch with
c8645e74113c6 ("configs: imx8m: Prepare imx8m-venice boards for HAB support")

Do you have an IMX8M board on hand to check against to see if you see
the same error in the SPL?

Fabio, if you enable CONFIG_DM_RNG on an imx8m{m,p}_evk do you get the
following in the SPL?
Couldn't bind rng driver (-96)
SEC0:  RNG instantiated

sec_init failed!

Best Regards,

Tim

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Fabio Estevam]

Hi Tim,

On Thu, Apr 18, 2024 at 2:54 PM Tim Harvey <tharvey@gateworks.com> wrote:

> Fabio, if you enable CONFIG_DM_RNG on an imx8m{m,p}_evk do you get the
> following in the SPL?
> Couldn't bind rng driver (-96)
> SEC0:  RNG instantiated
>
> sec_init failed!

Yes, if I add CONFIG_DM_RNG=y to imx8mm_evk_defconfig I get:

U-Boot SPL 2024.04-00793-g3434b88d2c2f-dirty (Apr 18 2024 - 14:58:57 -0300)
No pmic
Couldn't bind rng driver (-96)
SEC0:  RNG instantiated

sec_init failed!

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Marek Vasut]

On 4/18/24 8:02 PM, Fabio Estevam wrote:
> Hi Tim,
> 
> On Thu, Apr 18, 2024 at 2:54 PM Tim Harvey <tharvey@gateworks.com> wrote:
> 
>> Fabio, if you enable CONFIG_DM_RNG on an imx8m{m,p}_evk do you get the
>> following in the SPL?
>> Couldn't bind rng driver (-96)
>> SEC0:  RNG instantiated
>>
>> sec_init failed!
> 
> Yes, if I add CONFIG_DM_RNG=y to imx8mm_evk_defconfig I get:
> 
> U-Boot SPL 2024.04-00793-g3434b88d2c2f-dirty (Apr 18 2024 - 14:58:57 -0300)
> No pmic
> Couldn't bind rng driver (-96)
> SEC0:  RNG instantiated
> 
> sec_init failed!

Interesting. Which TFA blob version do you use ? I used the mainline 
2.10 for my tests.

btw. 'no pmic' ? Is that expected ?

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Fabio Estevam]

Hi Marek,

On Thu, Apr 18, 2024 at 3:42 PM Marek Vasut <marex@denx.de> wrote:

> Interesting. Which TFA blob version do you use ? I used the mainline
> 2.10 for my tests.

I tested with mainline TFA 2.10 and also with NXP 2.8. The error
happens in both cases.

> btw. 'no pmic' ? Is that expected ?

Yes, this is a separate issue. It happens because there are two PMIC
variants on the imx8mm evk.

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Fabio Estevam]

On Thu, Apr 18, 2024 at 4:05 PM Fabio Estevam <festevam@gmail.com> wrote:

> I tested with mainline TFA 2.10 and also with NXP 2.8. The error
> happens in both cases.

I don't get the error if I pass CONFIG_FSL_CAAM_JR_NTZ_ACCESS=y:

U-Boot SPL 2024.04-00793-g3434b88d2c2f-dirty (Apr 18 2024 - 21:46:06 -0300)
No pmic
SEC0:  RNG instantiated
WDT:   Started watchdog@30280000 with servicing every 1000ms (60s timeout)
Trying to boot from MMC1
NOTICE:  Do not release JR0 to NS as it can be used by HAB
NOTICE:  BL31: v2.10.3(release):lts-v2.10.3
NOTICE:  BL31: Built : 21:04:50, Apr 15 2024

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Fabio Estevam]

On Thu, Apr 18, 2024 at 9:47 PM Fabio Estevam <festevam@gmail.com> wrote:

> I don't get the error if I pass CONFIG_FSL_CAAM_JR_NTZ_ACCESS=y:

Ops, sorry. This is not correct. CONFIG_DM_RNG was unselected. Please discard.

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Tim Harvey]

On Thu, Apr 18, 2024 at 11:42 AM Marek Vasut <marex@denx.de> wrote:
>
> On 4/18/24 8:02 PM, Fabio Estevam wrote:
> > Hi Tim,
> >
> > On Thu, Apr 18, 2024 at 2:54 PM Tim Harvey <tharvey@gateworks.com> wrote:
> >
> >> Fabio, if you enable CONFIG_DM_RNG on an imx8m{m,p}_evk do you get the
> >> following in the SPL?
> >> Couldn't bind rng driver (-96)
> >> SEC0:  RNG instantiated
> >>
> >> sec_init failed!
> >
> > Yes, if I add CONFIG_DM_RNG=y to imx8mm_evk_defconfig I get:
> >
> > U-Boot SPL 2024.04-00793-g3434b88d2c2f-dirty (Apr 18 2024 - 14:58:57 -0300)
> > No pmic
> > Couldn't bind rng driver (-96)
> > SEC0:  RNG instantiated
> >
> > sec_init failed!
>
> Interesting. Which TFA blob version do you use ? I used the mainline
> 2.10 for my tests.

Marek,

Were you able to reproduce this as well with the board you enabled
DM_RNG for? If it does work fine what dtb were you using... perhaps
there is something in its u-boot.dtsi that we need?

The error -EPFNOSUPPORT is interesting and helps point to the only
place it can be where the comment says the strange errno is to make
this easier to find:
https://elixir.bootlin.com/u-boot/latest/source/drivers/core/uclass.c#L70:
        if (!uc_drv) {
                debug("Cannot find uclass for id %d: please add the
UCLASS_DRIVER() declaration for this UCLASS_... id\n",
                      id);
                /*
                 * Use a strange error to make this case easier to find. When
                 * a uclass is not available it can prevent driver model from
                 * starting up and this failure is otherwise hard to debug.
                 */
                return -EPFNOSUPPORT;
        }

I'm not very familiar with the dm driver binding - does the
U-BOOT_DRIVER usage in drivers/crypto/fsl/rng.c need to be refactored
to use UCLASS_DRIVER for it to be usable in both SPL and U-Boot?

Honestly I don't know why we need DM_RNG in SPL anyway and we could
just add support for disabling it there to avoid unwanted bloat.

Tim

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Marek Vasut]

On 4/19/24 5:24 PM, Tim Harvey wrote:
> On Thu, Apr 18, 2024 at 11:42 AM Marek Vasut <marex@denx.de> wrote:
>>
>> On 4/18/24 8:02 PM, Fabio Estevam wrote:
>>> Hi Tim,
>>>
>>> On Thu, Apr 18, 2024 at 2:54 PM Tim Harvey <tharvey@gateworks.com> wrote:
>>>
>>>> Fabio, if you enable CONFIG_DM_RNG on an imx8m{m,p}_evk do you get the
>>>> following in the SPL?
>>>> Couldn't bind rng driver (-96)
>>>> SEC0:  RNG instantiated
>>>>
>>>> sec_init failed!
>>>
>>> Yes, if I add CONFIG_DM_RNG=y to imx8mm_evk_defconfig I get:
>>>
>>> U-Boot SPL 2024.04-00793-g3434b88d2c2f-dirty (Apr 18 2024 - 14:58:57 -0300)
>>> No pmic
>>> Couldn't bind rng driver (-96)
>>> SEC0:  RNG instantiated
>>>
>>> sec_init failed!
>>
>> Interesting. Which TFA blob version do you use ? I used the mainline
>> 2.10 for my tests.
> 
> Marek,
> 
> Were you able to reproduce this as well with the board you enabled
> DM_RNG for? If it does work fine what dtb were you using... perhaps
> there is something in its u-boot.dtsi that we need?

This one arch/arm/dts/imx8mp-dhcom-pdk3.dts , see log below. The build 
has a few extra patches in it, but nothing which affects the KASLR:

$ export SOURCE_DATE_EPOCH=1672531200 ; echo tst > .scmversion
$ make imx8mp_dhcom_pdk3_defconfig ; make

U-Boot SPL 2024.07-rc1tst (Jan 01 2023 - 00:00:00 +0000)
DDR:   4096 MiB [0x5]
DDR:   Inline ECC enabled
WDT:   Started watchdog@30280000 with servicing every 1000ms (60s timeout)
Trying to boot from BOOTROM
Boot Stage: Primary boot
image offset 0x1000, pagesize 0x1, ivt offset 0x0
NOTICE:  Do not release JR0 to NS as it can be used by HAB
NOTICE:  BL31: v2.10.0  (release):v2.10.0-5-gfb51ca229
NOTICE:  BL31: Built : 20:30:36, Apr 23 2024


U-Boot 2024.07-rc1tst (Jan 01 2023 - 00:00:00 +0000)

CPU:   Freescale i.MX8MP[8] rev1.1 1600 MHz (running at 1200 MHz)
CPU:   Industrial temperature grade (-40C to 105C) at 70C
Reset cause: POR
Model: DH electronics i.MX8M Plus DHCOM Premium Developer Kit (3)
DRAM:  3.5 GiB
Core:  183 devices, 34 uclasses, devicetree: separate
WDT:   Started watchdog@30280000 with servicing every 1000ms (60s timeout)
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
Loading Environment from SPIFlash... SF: Detected w25q128jw with page 
size 256 Bytes, erase size 4 KiB, total 16 MiB
OK
In:    serial
Out:   serial
Err:   serial
SEC0:  RNG instantiated
Net:   eth1: ethernet@30be0000, eth0: ethernet@30bf0000
...

> The error -EPFNOSUPPORT is interesting and helps point to the only
> place it can be where the comment says the strange errno is to make
> this easier to find:
> https://elixir.bootlin.com/u-boot/latest/source/drivers/core/uclass.c#L70:
>          if (!uc_drv) {
>                  debug("Cannot find uclass for id %d: please add the
> UCLASS_DRIVER() declaration for this UCLASS_... id\n",
>                        id);
>                  /*
>                   * Use a strange error to make this case easier to find. When
>                   * a uclass is not available it can prevent driver model from
>                   * starting up and this failure is otherwise hard to debug.
>                   */
>                  return -EPFNOSUPPORT;
>          }
> 
> I'm not very familiar with the dm driver binding - does the
> U-BOOT_DRIVER usage in drivers/crypto/fsl/rng.c need to be refactored
> to use UCLASS_DRIVER for it to be usable in both SPL and U-Boot?

I don't think you need the CAAM RNG in SPL in the first place, or do you ?

> Honestly I don't know why we need DM_RNG in SPL anyway and we could
> just add support for disabling it there to avoid unwanted bloat.

I think you can disable it , yes.

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Tim Harvey]

On Tue, Apr 23, 2024 at 4:18 PM Marek Vasut <marex@denx.de> wrote:
>
> On 4/19/24 5:24 PM, Tim Harvey wrote:
> > On Thu, Apr 18, 2024 at 11:42 AM Marek Vasut <marex@denx.de> wrote:
> >>
> >> On 4/18/24 8:02 PM, Fabio Estevam wrote:
> >>> Hi Tim,
> >>>
> >>> On Thu, Apr 18, 2024 at 2:54 PM Tim Harvey <tharvey@gateworks.com> wrote:
> >>>
> >>>> Fabio, if you enable CONFIG_DM_RNG on an imx8m{m,p}_evk do you get the
> >>>> following in the SPL?
> >>>> Couldn't bind rng driver (-96)
> >>>> SEC0:  RNG instantiated
> >>>>
> >>>> sec_init failed!
> >>>
> >>> Yes, if I add CONFIG_DM_RNG=y to imx8mm_evk_defconfig I get:
> >>>
> >>> U-Boot SPL 2024.04-00793-g3434b88d2c2f-dirty (Apr 18 2024 - 14:58:57 -0300)
> >>> No pmic
> >>> Couldn't bind rng driver (-96)
> >>> SEC0:  RNG instantiated
> >>>
> >>> sec_init failed!
> >>
> >> Interesting. Which TFA blob version do you use ? I used the mainline
> >> 2.10 for my tests.
> >
> > Marek,
> >
> > Were you able to reproduce this as well with the board you enabled
> > DM_RNG for? If it does work fine what dtb were you using... perhaps
> > there is something in its u-boot.dtsi that we need?
>
> This one arch/arm/dts/imx8mp-dhcom-pdk3.dts , see log below. The build
> has a few extra patches in it, but nothing which affects the KASLR:
>
> $ export SOURCE_DATE_EPOCH=1672531200 ; echo tst > .scmversion
> $ make imx8mp_dhcom_pdk3_defconfig ; make
>
> U-Boot SPL 2024.07-rc1tst (Jan 01 2023 - 00:00:00 +0000)
> DDR:   4096 MiB [0x5]
> DDR:   Inline ECC enabled
> WDT:   Started watchdog@30280000 with servicing every 1000ms (60s timeout)
> Trying to boot from BOOTROM
> Boot Stage: Primary boot
> image offset 0x1000, pagesize 0x1, ivt offset 0x0
> NOTICE:  Do not release JR0 to NS as it can be used by HAB
> NOTICE:  BL31: v2.10.0  (release):v2.10.0-5-gfb51ca229
> NOTICE:  BL31: Built : 20:30:36, Apr 23 2024
>
>
> U-Boot 2024.07-rc1tst (Jan 01 2023 - 00:00:00 +0000)
>
> CPU:   Freescale i.MX8MP[8] rev1.1 1600 MHz (running at 1200 MHz)
> CPU:   Industrial temperature grade (-40C to 105C) at 70C
> Reset cause: POR
> Model: DH electronics i.MX8M Plus DHCOM Premium Developer Kit (3)
> DRAM:  3.5 GiB
> Core:  183 devices, 34 uclasses, devicetree: separate
> WDT:   Started watchdog@30280000 with servicing every 1000ms (60s timeout)
> MMC:   FSL_SDHC: 0, FSL_SDHC: 1
> Loading Environment from SPIFlash... SF: Detected w25q128jw with page
> size 256 Bytes, erase size 4 KiB, total 16 MiB
> OK
> In:    serial
> Out:   serial
> Err:   serial
> SEC0:  RNG instantiated
> Net:   eth1: ethernet@30be0000, eth0: ethernet@30bf0000
> ...
>
> > The error -EPFNOSUPPORT is interesting and helps point to the only
> > place it can be where the comment says the strange errno is to make
> > this easier to find:
> > https://elixir.bootlin.com/u-boot/latest/source/drivers/core/uclass.c#L70:
> >          if (!uc_drv) {
> >                  debug("Cannot find uclass for id %d: please add the
> > UCLASS_DRIVER() declaration for this UCLASS_... id\n",
> >                        id);
> >                  /*
> >                   * Use a strange error to make this case easier to find. When
> >                   * a uclass is not available it can prevent driver model from
> >                   * starting up and this failure is otherwise hard to debug.
> >                   */
> >                  return -EPFNOSUPPORT;
> >          }
> >
> > I'm not very familiar with the dm driver binding - does the
> > U-BOOT_DRIVER usage in drivers/crypto/fsl/rng.c need to be refactored
> > to use UCLASS_DRIVER for it to be usable in both SPL and U-Boot?
>
> I don't think you need the CAAM RNG in SPL in the first place, or do you ?
>
> > Honestly I don't know why we need DM_RNG in SPL anyway and we could
> > just add support for disabling it there to avoid unwanted bloat.
>
> I think you can disable it , yes.

Marek,

Would it be advantageous for the kaslr-seed to be added automatically
from image_setup_libfdt?

I notice arch/arm/cpu/armv8/fsl-layerscape/fdt.c:ft_cpu_setup does
this and board/raspberrypi/rpi/rpi.c looks like it copies kaslr-seed
from the control fdt which I assume was added by an earlier layer for
that target.

I'm not clear if there is a disadvantage to automatically adding this
node if DM_RNG is enabled.

Best Regards,

Tim

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Marek Vasut]

On 4/29/24 9:10 PM, Tim Harvey wrote:
> On Tue, Apr 23, 2024 at 4:18 PM Marek Vasut <marex@denx.de> wrote:
>>
>> On 4/19/24 5:24 PM, Tim Harvey wrote:
>>> On Thu, Apr 18, 2024 at 11:42 AM Marek Vasut <marex@denx.de> wrote:
>>>>
>>>> On 4/18/24 8:02 PM, Fabio Estevam wrote:
>>>>> Hi Tim,
>>>>>
>>>>> On Thu, Apr 18, 2024 at 2:54 PM Tim Harvey <tharvey@gateworks.com> wrote:
>>>>>
>>>>>> Fabio, if you enable CONFIG_DM_RNG on an imx8m{m,p}_evk do you get the
>>>>>> following in the SPL?
>>>>>> Couldn't bind rng driver (-96)
>>>>>> SEC0:  RNG instantiated
>>>>>>
>>>>>> sec_init failed!
>>>>>
>>>>> Yes, if I add CONFIG_DM_RNG=y to imx8mm_evk_defconfig I get:
>>>>>
>>>>> U-Boot SPL 2024.04-00793-g3434b88d2c2f-dirty (Apr 18 2024 - 14:58:57 -0300)
>>>>> No pmic
>>>>> Couldn't bind rng driver (-96)
>>>>> SEC0:  RNG instantiated
>>>>>
>>>>> sec_init failed!
>>>>
>>>> Interesting. Which TFA blob version do you use ? I used the mainline
>>>> 2.10 for my tests.
>>>
>>> Marek,
>>>
>>> Were you able to reproduce this as well with the board you enabled
>>> DM_RNG for? If it does work fine what dtb were you using... perhaps
>>> there is something in its u-boot.dtsi that we need?
>>
>> This one arch/arm/dts/imx8mp-dhcom-pdk3.dts , see log below. The build
>> has a few extra patches in it, but nothing which affects the KASLR:
>>
>> $ export SOURCE_DATE_EPOCH=1672531200 ; echo tst > .scmversion
>> $ make imx8mp_dhcom_pdk3_defconfig ; make
>>
>> U-Boot SPL 2024.07-rc1tst (Jan 01 2023 - 00:00:00 +0000)
>> DDR:   4096 MiB [0x5]
>> DDR:   Inline ECC enabled
>> WDT:   Started watchdog@30280000 with servicing every 1000ms (60s timeout)
>> Trying to boot from BOOTROM
>> Boot Stage: Primary boot
>> image offset 0x1000, pagesize 0x1, ivt offset 0x0
>> NOTICE:  Do not release JR0 to NS as it can be used by HAB
>> NOTICE:  BL31: v2.10.0  (release):v2.10.0-5-gfb51ca229
>> NOTICE:  BL31: Built : 20:30:36, Apr 23 2024
>>
>>
>> U-Boot 2024.07-rc1tst (Jan 01 2023 - 00:00:00 +0000)
>>
>> CPU:   Freescale i.MX8MP[8] rev1.1 1600 MHz (running at 1200 MHz)
>> CPU:   Industrial temperature grade (-40C to 105C) at 70C
>> Reset cause: POR
>> Model: DH electronics i.MX8M Plus DHCOM Premium Developer Kit (3)
>> DRAM:  3.5 GiB
>> Core:  183 devices, 34 uclasses, devicetree: separate
>> WDT:   Started watchdog@30280000 with servicing every 1000ms (60s timeout)
>> MMC:   FSL_SDHC: 0, FSL_SDHC: 1
>> Loading Environment from SPIFlash... SF: Detected w25q128jw with page
>> size 256 Bytes, erase size 4 KiB, total 16 MiB
>> OK
>> In:    serial
>> Out:   serial
>> Err:   serial
>> SEC0:  RNG instantiated
>> Net:   eth1: ethernet@30be0000, eth0: ethernet@30bf0000
>> ...
>>
>>> The error -EPFNOSUPPORT is interesting and helps point to the only
>>> place it can be where the comment says the strange errno is to make
>>> this easier to find:
>>> https://elixir.bootlin.com/u-boot/latest/source/drivers/core/uclass.c#L70:
>>>           if (!uc_drv) {
>>>                   debug("Cannot find uclass for id %d: please add the
>>> UCLASS_DRIVER() declaration for this UCLASS_... id\n",
>>>                         id);
>>>                   /*
>>>                    * Use a strange error to make this case easier to find. When
>>>                    * a uclass is not available it can prevent driver model from
>>>                    * starting up and this failure is otherwise hard to debug.
>>>                    */
>>>                   return -EPFNOSUPPORT;
>>>           }
>>>
>>> I'm not very familiar with the dm driver binding - does the
>>> U-BOOT_DRIVER usage in drivers/crypto/fsl/rng.c need to be refactored
>>> to use UCLASS_DRIVER for it to be usable in both SPL and U-Boot?
>>
>> I don't think you need the CAAM RNG in SPL in the first place, or do you ?
>>
>>> Honestly I don't know why we need DM_RNG in SPL anyway and we could
>>> just add support for disabling it there to avoid unwanted bloat.
>>
>> I think you can disable it , yes.
> 
> Marek,
> 
> Would it be advantageous for the kaslr-seed to be added automatically
> from image_setup_libfdt?

Yes, can you prepare a patch ? (I wanted to do this, just haven't had 
the time)

> I notice arch/arm/cpu/armv8/fsl-layerscape/fdt.c:ft_cpu_setup does
> this and board/raspberrypi/rpi/rpi.c looks like it copies kaslr-seed
> from the control fdt which I assume was added by an earlier layer for
> that target.

Right, exactly, this .

> I'm not clear if there is a disadvantage to automatically adding this
> node if DM_RNG is enabled.

I would say, add it.

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Tim Harvey]

On Mon, Apr 29, 2024 at 1:51 PM Marek Vasut <marex@denx.de> wrote:
>
> On 4/29/24 9:10 PM, Tim Harvey wrote:
> > On Tue, Apr 23, 2024 at 4:18 PM Marek Vasut <marex@denx.de> wrote:
> >>
> >> On 4/19/24 5:24 PM, Tim Harvey wrote:
> >>> On Thu, Apr 18, 2024 at 11:42 AM Marek Vasut <marex@denx.de> wrote:
> >>>>
> >>>> On 4/18/24 8:02 PM, Fabio Estevam wrote:
> >>>>> Hi Tim,
> >>>>>
> >>>>> On Thu, Apr 18, 2024 at 2:54 PM Tim Harvey <tharvey@gateworks.com> wrote:
> >>>>>
> >>>>>> Fabio, if you enable CONFIG_DM_RNG on an imx8m{m,p}_evk do you get the
> >>>>>> following in the SPL?
> >>>>>> Couldn't bind rng driver (-96)
> >>>>>> SEC0:  RNG instantiated
> >>>>>>
> >>>>>> sec_init failed!
> >>>>>
> >>>>> Yes, if I add CONFIG_DM_RNG=y to imx8mm_evk_defconfig I get:
> >>>>>
> >>>>> U-Boot SPL 2024.04-00793-g3434b88d2c2f-dirty (Apr 18 2024 - 14:58:57 -0300)
> >>>>> No pmic
> >>>>> Couldn't bind rng driver (-96)
> >>>>> SEC0:  RNG instantiated
> >>>>>
> >>>>> sec_init failed!
> >>>>
> >>>> Interesting. Which TFA blob version do you use ? I used the mainline
> >>>> 2.10 for my tests.
> >>>
> >>> Marek,
> >>>
> >>> Were you able to reproduce this as well with the board you enabled
> >>> DM_RNG for? If it does work fine what dtb were you using... perhaps
> >>> there is something in its u-boot.dtsi that we need?
> >>
> >> This one arch/arm/dts/imx8mp-dhcom-pdk3.dts , see log below. The build
> >> has a few extra patches in it, but nothing which affects the KASLR:
> >>
> >> $ export SOURCE_DATE_EPOCH=1672531200 ; echo tst > .scmversion
> >> $ make imx8mp_dhcom_pdk3_defconfig ; make
> >>
> >> U-Boot SPL 2024.07-rc1tst (Jan 01 2023 - 00:00:00 +0000)
> >> DDR:   4096 MiB [0x5]
> >> DDR:   Inline ECC enabled
> >> WDT:   Started watchdog@30280000 with servicing every 1000ms (60s timeout)
> >> Trying to boot from BOOTROM
> >> Boot Stage: Primary boot
> >> image offset 0x1000, pagesize 0x1, ivt offset 0x0
> >> NOTICE:  Do not release JR0 to NS as it can be used by HAB
> >> NOTICE:  BL31: v2.10.0  (release):v2.10.0-5-gfb51ca229
> >> NOTICE:  BL31: Built : 20:30:36, Apr 23 2024
> >>
> >>
> >> U-Boot 2024.07-rc1tst (Jan 01 2023 - 00:00:00 +0000)
> >>
> >> CPU:   Freescale i.MX8MP[8] rev1.1 1600 MHz (running at 1200 MHz)
> >> CPU:   Industrial temperature grade (-40C to 105C) at 70C
> >> Reset cause: POR
> >> Model: DH electronics i.MX8M Plus DHCOM Premium Developer Kit (3)
> >> DRAM:  3.5 GiB
> >> Core:  183 devices, 34 uclasses, devicetree: separate
> >> WDT:   Started watchdog@30280000 with servicing every 1000ms (60s timeout)
> >> MMC:   FSL_SDHC: 0, FSL_SDHC: 1
> >> Loading Environment from SPIFlash... SF: Detected w25q128jw with page
> >> size 256 Bytes, erase size 4 KiB, total 16 MiB
> >> OK
> >> In:    serial
> >> Out:   serial
> >> Err:   serial
> >> SEC0:  RNG instantiated
> >> Net:   eth1: ethernet@30be0000, eth0: ethernet@30bf0000
> >> ...
> >>
> >>> The error -EPFNOSUPPORT is interesting and helps point to the only
> >>> place it can be where the comment says the strange errno is to make
> >>> this easier to find:
> >>> https://elixir.bootlin.com/u-boot/latest/source/drivers/core/uclass.c#L70:
> >>>           if (!uc_drv) {
> >>>                   debug("Cannot find uclass for id %d: please add the
> >>> UCLASS_DRIVER() declaration for this UCLASS_... id\n",
> >>>                         id);
> >>>                   /*
> >>>                    * Use a strange error to make this case easier to find. When
> >>>                    * a uclass is not available it can prevent driver model from
> >>>                    * starting up and this failure is otherwise hard to debug.
> >>>                    */
> >>>                   return -EPFNOSUPPORT;
> >>>           }
> >>>
> >>> I'm not very familiar with the dm driver binding - does the
> >>> U-BOOT_DRIVER usage in drivers/crypto/fsl/rng.c need to be refactored
> >>> to use UCLASS_DRIVER for it to be usable in both SPL and U-Boot?
> >>
> >> I don't think you need the CAAM RNG in SPL in the first place, or do you ?
> >>
> >>> Honestly I don't know why we need DM_RNG in SPL anyway and we could
> >>> just add support for disabling it there to avoid unwanted bloat.
> >>
> >> I think you can disable it , yes.
> >
> > Marek,
> >
> > Would it be advantageous for the kaslr-seed to be added automatically
> > from image_setup_libfdt?
>
> Yes, can you prepare a patch ? (I wanted to do this, just haven't had
> the time)
>
> > I notice arch/arm/cpu/armv8/fsl-layerscape/fdt.c:ft_cpu_setup does
> > this and board/raspberrypi/rpi/rpi.c looks like it copies kaslr-seed
> > from the control fdt which I assume was added by an earlier layer for
> > that target.
>
> Right, exactly, this .
>
> > I'm not clear if there is a disadvantage to automatically adding this
> > node if DM_RNG is enabled.
>
> I would say, add it.

Yes, I'll submit something this week.

Best Regards,

Tim

Re: [PATCH] ARM: imx: Enable kaslrseed command on DH i.MX8M Plus DHCOM

[Marek Vasut]

On 4/29/24 10:52 PM, Tim Harvey wrote:
> On Mon, Apr 29, 2024 at 1:51 PM Marek Vasut <marex@denx.de> wrote:
>>
>> On 4/29/24 9:10 PM, Tim Harvey wrote:
>>> On Tue, Apr 23, 2024 at 4:18 PM Marek Vasut <marex@denx.de> wrote:
>>>>
>>>> On 4/19/24 5:24 PM, Tim Harvey wrote:
>>>>> On Thu, Apr 18, 2024 at 11:42 AM Marek Vasut <marex@denx.de> wrote:
>>>>>>
>>>>>> On 4/18/24 8:02 PM, Fabio Estevam wrote:
>>>>>>> Hi Tim,
>>>>>>>
>>>>>>> On Thu, Apr 18, 2024 at 2:54 PM Tim Harvey <tharvey@gateworks.com> wrote:
>>>>>>>
>>>>>>>> Fabio, if you enable CONFIG_DM_RNG on an imx8m{m,p}_evk do you get the
>>>>>>>> following in the SPL?
>>>>>>>> Couldn't bind rng driver (-96)
>>>>>>>> SEC0:  RNG instantiated
>>>>>>>>
>>>>>>>> sec_init failed!
>>>>>>>
>>>>>>> Yes, if I add CONFIG_DM_RNG=y to imx8mm_evk_defconfig I get:
>>>>>>>
>>>>>>> U-Boot SPL 2024.04-00793-g3434b88d2c2f-dirty (Apr 18 2024 - 14:58:57 -0300)
>>>>>>> No pmic
>>>>>>> Couldn't bind rng driver (-96)
>>>>>>> SEC0:  RNG instantiated
>>>>>>>
>>>>>>> sec_init failed!
>>>>>>
>>>>>> Interesting. Which TFA blob version do you use ? I used the mainline
>>>>>> 2.10 for my tests.
>>>>>
>>>>> Marek,
>>>>>
>>>>> Were you able to reproduce this as well with the board you enabled
>>>>> DM_RNG for? If it does work fine what dtb were you using... perhaps
>>>>> there is something in its u-boot.dtsi that we need?
>>>>
>>>> This one arch/arm/dts/imx8mp-dhcom-pdk3.dts , see log below. The build
>>>> has a few extra patches in it, but nothing which affects the KASLR:
>>>>
>>>> $ export SOURCE_DATE_EPOCH=1672531200 ; echo tst > .scmversion
>>>> $ make imx8mp_dhcom_pdk3_defconfig ; make
>>>>
>>>> U-Boot SPL 2024.07-rc1tst (Jan 01 2023 - 00:00:00 +0000)
>>>> DDR:   4096 MiB [0x5]
>>>> DDR:   Inline ECC enabled
>>>> WDT:   Started watchdog@30280000 with servicing every 1000ms (60s timeout)
>>>> Trying to boot from BOOTROM
>>>> Boot Stage: Primary boot
>>>> image offset 0x1000, pagesize 0x1, ivt offset 0x0
>>>> NOTICE:  Do not release JR0 to NS as it can be used by HAB
>>>> NOTICE:  BL31: v2.10.0  (release):v2.10.0-5-gfb51ca229
>>>> NOTICE:  BL31: Built : 20:30:36, Apr 23 2024
>>>>
>>>>
>>>> U-Boot 2024.07-rc1tst (Jan 01 2023 - 00:00:00 +0000)
>>>>
>>>> CPU:   Freescale i.MX8MP[8] rev1.1 1600 MHz (running at 1200 MHz)
>>>> CPU:   Industrial temperature grade (-40C to 105C) at 70C
>>>> Reset cause: POR
>>>> Model: DH electronics i.MX8M Plus DHCOM Premium Developer Kit (3)
>>>> DRAM:  3.5 GiB
>>>> Core:  183 devices, 34 uclasses, devicetree: separate
>>>> WDT:   Started watchdog@30280000 with servicing every 1000ms (60s timeout)
>>>> MMC:   FSL_SDHC: 0, FSL_SDHC: 1
>>>> Loading Environment from SPIFlash... SF: Detected w25q128jw with page
>>>> size 256 Bytes, erase size 4 KiB, total 16 MiB
>>>> OK
>>>> In:    serial
>>>> Out:   serial
>>>> Err:   serial
>>>> SEC0:  RNG instantiated
>>>> Net:   eth1: ethernet@30be0000, eth0: ethernet@30bf0000
>>>> ...
>>>>
>>>>> The error -EPFNOSUPPORT is interesting and helps point to the only
>>>>> place it can be where the comment says the strange errno is to make
>>>>> this easier to find:
>>>>> https://elixir.bootlin.com/u-boot/latest/source/drivers/core/uclass.c#L70:
>>>>>            if (!uc_drv) {
>>>>>                    debug("Cannot find uclass for id %d: please add the
>>>>> UCLASS_DRIVER() declaration for this UCLASS_... id\n",
>>>>>                          id);
>>>>>                    /*
>>>>>                     * Use a strange error to make this case easier to find. When
>>>>>                     * a uclass is not available it can prevent driver model from
>>>>>                     * starting up and this failure is otherwise hard to debug.
>>>>>                     */
>>>>>                    return -EPFNOSUPPORT;
>>>>>            }
>>>>>
>>>>> I'm not very familiar with the dm driver binding - does the
>>>>> U-BOOT_DRIVER usage in drivers/crypto/fsl/rng.c need to be refactored
>>>>> to use UCLASS_DRIVER for it to be usable in both SPL and U-Boot?
>>>>
>>>> I don't think you need the CAAM RNG in SPL in the first place, or do you ?
>>>>
>>>>> Honestly I don't know why we need DM_RNG in SPL anyway and we could
>>>>> just add support for disabling it there to avoid unwanted bloat.
>>>>
>>>> I think you can disable it , yes.
>>>
>>> Marek,
>>>
>>> Would it be advantageous for the kaslr-seed to be added automatically
>>> from image_setup_libfdt?
>>
>> Yes, can you prepare a patch ? (I wanted to do this, just haven't had
>> the time)
>>
>>> I notice arch/arm/cpu/armv8/fsl-layerscape/fdt.c:ft_cpu_setup does
>>> this and board/raspberrypi/rpi/rpi.c looks like it copies kaslr-seed
>>> from the control fdt which I assume was added by an earlier layer for
>>> that target.
>>
>> Right, exactly, this .
>>
>>> I'm not clear if there is a disadvantage to automatically adding this
>>> node if DM_RNG is enabled.
>>
>> I would say, add it.
> 
> Yes, I'll submit something this week.

Thank you, much appreciated.