[PATCH v3 0/4] Raspberry Pi 4 HWRNG Support

[PATCH v3 0/4] Raspberry Pi 4 HWRNG Support

[Stephen Brennan]

This patch series enables support for the HWRNG included on the Raspberry
Pi 4.  It is simply a rebase of Stefan's branch [1]. I went ahead and
tested this out on a Pi 4.  Prior to this patch series, attempting to use
the hwrng gives:

    $ head -c 2 /dev/hwrng
    head: /dev/hwrng: Input/output error

After this series, the same command gives two random bytes.

Changes in v3:
- drop interrupts from bcm2711 rng node
- move bcm283x rng into bcm2835-common.dtsi
- add reviewed-by tag
- separated out patch 3 into two parts

Changes in v2:
- specify the correct size for the region in the dts, refactor bcm283x rng

---

Stefan Wahren (2):
  dt-bindings: rng: add BCM2711 RNG compatible
  hwrng: iproc-rng200: Add support for BCM2711

Stephen Brennan (2):
  ARM: dts: bcm2835: Move rng definition to common location
  ARM: dts: bcm2711: Enable HWRNG support

 .../devicetree/bindings/rng/brcm,iproc-rng200.txt          | 1 +
 arch/arm/boot/dts/bcm2711.dtsi                             | 7 +++----
 arch/arm/boot/dts/bcm2835-common.dtsi                      | 6 ++++++
 arch/arm/boot/dts/bcm283x.dtsi                             | 6 ------
 drivers/char/hw_random/Kconfig                             | 2 +-
 drivers/char/hw_random/iproc-rng200.c                      | 1 +
 6 files changed, 12 insertions(+), 11 deletions(-)

-- 
2.24.0

[PATCH v3 1/4] dt-bindings: rng: add BCM2711 RNG compatible

[Stephen Brennan]

From: Stefan Wahren <wahrenst@gmx.net>

The BCM2711 has a RNG200 block, so document its compatible string.

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Stephen Brennan <stephen@brennan.io>
---
 Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt b/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt
index c223e54452da..802523196ee5 100644
--- a/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt
+++ b/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt
@@ -2,6 +2,7 @@ HWRNG support for the iproc-rng200 driver
 
 Required properties:
 - compatible : Must be one of:
+	       "brcm,bcm2711-rng200"
 	       "brcm,bcm7211-rng200"
 	       "brcm,bcm7278-rng200"
 	       "brcm,iproc-rng200"
-- 
2.24.0

[PATCH v3 2/4] hwrng: iproc-rng200: Add support for BCM2711

[Stephen Brennan]

From: Stefan Wahren <wahrenst@gmx.net>

BCM2711 features a RNG200 hardware random number generator block.
So make the driver available.

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Stephen Brennan <stephen@brennan.io>
Reviewed-by: Matthias Brugger <mbrugger@suse.com>
---
 drivers/char/hw_random/Kconfig        | 2 +-
 drivers/char/hw_random/iproc-rng200.c | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 7c7fecfa2fb2..77e848fca531 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -90,7 +90,7 @@ config HW_RANDOM_BCM2835
 
 config HW_RANDOM_IPROC_RNG200
 	tristate "Broadcom iProc/STB RNG200 support"
-	depends on ARCH_BCM_IPROC || ARCH_BRCMSTB
+	depends on ARCH_BCM_IPROC || ARCH_BCM2835 || ARCH_BRCMSTB
 	default HW_RANDOM
 	---help---
 	  This driver provides kernel-side support for the RNG200
diff --git a/drivers/char/hw_random/iproc-rng200.c b/drivers/char/hw_random/iproc-rng200.c
index 899ff25f4f28..32d9fe61a225 100644
--- a/drivers/char/hw_random/iproc-rng200.c
+++ b/drivers/char/hw_random/iproc-rng200.c
@@ -213,6 +213,7 @@ static int iproc_rng200_probe(struct platform_device *pdev)
 }
 
 static const struct of_device_id iproc_rng200_of_match[] = {
+	{ .compatible = "brcm,bcm2711-rng200", },
 	{ .compatible = "brcm,bcm7211-rng200", },
 	{ .compatible = "brcm,bcm7278-rng200", },
 	{ .compatible = "brcm,iproc-rng200", },
-- 
2.24.0

[PATCH v3 3/4] ARM: dts: bcm2835: Move rng definition to common location

[Stephen Brennan]

BCM2711 inherits from BCM283X, but has an incompatible HWRNG. Move this
node to bcm2835-common.dtsi, so that BCM2711 can define its own.

Signed-off-by: Stephen Brennan <stephen@brennan.io>
---

Changes in v3:
- moved the bcm2835 rng into bcm2835-common.dtsi rather than a new file
- split out enabling rng on bcm2711 into its own patch

 arch/arm/boot/dts/bcm2835-common.dtsi | 6 ++++++
 arch/arm/boot/dts/bcm283x.dtsi        | 6 ------
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/arm/boot/dts/bcm2835-common.dtsi b/arch/arm/boot/dts/bcm2835-common.dtsi
index fe1ab40c7f22..2b1d9d4c0cde 100644
--- a/arch/arm/boot/dts/bcm2835-common.dtsi
+++ b/arch/arm/boot/dts/bcm2835-common.dtsi
@@ -70,6 +70,12 @@ pm: watchdog@7e100000 {
 			system-power-controller;
 		};
 
+		rng@7e104000 {
+			compatible = "brcm,bcm2835-rng";
+			reg = <0x7e104000 0x10>;
+			interrupts = <2 29>;
+		};
+
 		pixelvalve@7e206000 {
 			compatible = "brcm,bcm2835-pixelvalve0";
 			reg = <0x7e206000 0x100>;
diff --git a/arch/arm/boot/dts/bcm283x.dtsi b/arch/arm/boot/dts/bcm283x.dtsi
index 3caaa57eb6c8..5219339fc27c 100644
--- a/arch/arm/boot/dts/bcm283x.dtsi
+++ b/arch/arm/boot/dts/bcm283x.dtsi
@@ -84,12 +84,6 @@ clocks: cprman@7e101000 {
 				<&dsi1 0>, <&dsi1 1>, <&dsi1 2>;
 		};
 
-		rng@7e104000 {
-			compatible = "brcm,bcm2835-rng";
-			reg = <0x7e104000 0x10>;
-			interrupts = <2 29>;
-		};
-
 		mailbox: mailbox@7e00b880 {
 			compatible = "brcm,bcm2835-mbox";
 			reg = <0x7e00b880 0x40>;
-- 
2.24.0

[PATCH v3 4/4] ARM: dts: bcm2711: Enable HWRNG support

[Stephen Brennan]

This enables hardware random number generator support for the BCM2711
on the Raspberry Pi 4 board.

Signed-off-by: Stephen Brennan <stephen@brennan.io>
---
 arch/arm/boot/dts/bcm2711.dtsi | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/arm/boot/dts/bcm2711.dtsi b/arch/arm/boot/dts/bcm2711.dtsi
index ac83dac2e6ba..ed0877d5a1e9 100644
--- a/arch/arm/boot/dts/bcm2711.dtsi
+++ b/arch/arm/boot/dts/bcm2711.dtsi
@@ -92,10 +92,9 @@ pm: watchdog@7e100000 {
 		};
 
 		rng@7e104000 {
-			interrupts = <GIC_SPI 125 IRQ_TYPE_LEVEL_HIGH>;
-
-			/* RNG is incompatible with brcm,bcm2835-rng */
-			status = "disabled";
+			compatible = "brcm,bcm2711-rng200";
+			reg = <0x7e104000 0x28>;
+			status = "okay";
 		};
 
 		uart2: serial@7e201400 {
-- 
2.24.0

Re: [PATCH v3 1/4] dt-bindings: rng: add BCM2711 RNG compatible

[Baruch Siach]

Hi Stephen, Stefan,

On Wed, Nov 20 2019, Stephen Brennan wrote:

> From: Stefan Wahren <wahrenst@gmx.net>
>
> The BCM2711 has a RNG200 block, so document its compatible string.
>
> Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
> Signed-off-by: Stephen Brennan <stephen@brennan.io>

Isn't that duplicate of Florian's commit 6223949a1531?

> ---
>  Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt b/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt
> index c223e54452da..802523196ee5 100644
> --- a/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt
> +++ b/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt
> @@ -2,6 +2,7 @@ HWRNG support for the iproc-rng200 driver
>  
>  Required properties:
>  - compatible : Must be one of:
> +	       "brcm,bcm2711-rng200"
>  	       "brcm,bcm7211-rng200"

Isn't this clear text duplication? Am I missing something obvious?

I was looking at versions of this patch series wondering why no one
noticed that.

baruch

>  	       "brcm,bcm7278-rng200"
>  	       "brcm,iproc-rng200"

-- 
     http://baruch.siach.name/blog/                  ~. .~   Tk Open Systems
=}------------------------------------------------ooO--U--Ooo------------{=
   - baruch@tkos.co.il - tel: +972.52.368.4656, http://www.tkos.co.il -

Re: [PATCH v3 2/4] hwrng: iproc-rng200: Add support for BCM2711

[Baruch Siach]

Hi Stephen, Stefan,

On Wed, Nov 20 2019, Stephen Brennan wrote:
> From: Stefan Wahren <wahrenst@gmx.net>
>
> BCM2711 features a RNG200 hardware random number generator block.
> So make the driver available.
>
> Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
> Signed-off-by: Stephen Brennan <stephen@brennan.io>
> Reviewed-by: Matthias Brugger <mbrugger@suse.com>
> ---
>  drivers/char/hw_random/Kconfig        | 2 +-
>  drivers/char/hw_random/iproc-rng200.c | 1 +
>  2 files changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
> index 7c7fecfa2fb2..77e848fca531 100644
> --- a/drivers/char/hw_random/Kconfig
> +++ b/drivers/char/hw_random/Kconfig
> @@ -90,7 +90,7 @@ config HW_RANDOM_BCM2835
>  
>  config HW_RANDOM_IPROC_RNG200
>  	tristate "Broadcom iProc/STB RNG200 support"
> -	depends on ARCH_BCM_IPROC || ARCH_BRCMSTB
> +	depends on ARCH_BCM_IPROC || ARCH_BCM2835 || ARCH_BRCMSTB
>  	default HW_RANDOM
>  	---help---
>  	  This driver provides kernel-side support for the RNG200
> diff --git a/drivers/char/hw_random/iproc-rng200.c b/drivers/char/hw_random/iproc-rng200.c
> index 899ff25f4f28..32d9fe61a225 100644
> --- a/drivers/char/hw_random/iproc-rng200.c
> +++ b/drivers/char/hw_random/iproc-rng200.c
> @@ -213,6 +213,7 @@ static int iproc_rng200_probe(struct platform_device *pdev)
>  }
>  
>  static const struct of_device_id iproc_rng200_of_match[] = {
> +	{ .compatible = "brcm,bcm2711-rng200", },
>  	{ .compatible = "brcm,bcm7211-rng200", },

Again, duplicate of commit 1fa6d053b2a5.

>  	{ .compatible = "brcm,bcm7278-rng200", },
>  	{ .compatible = "brcm,iproc-rng200", },

baruch

-- 
     http://baruch.siach.name/blog/                  ~. .~   Tk Open Systems
=}------------------------------------------------ooO--U--Ooo------------{=
   - baruch@tkos.co.il - tel: +972.52.368.4656, http://www.tkos.co.il -

Re: [PATCH v3 1/4] dt-bindings: rng: add BCM2711 RNG compatible

[Stephen Brennan]

Hi Baruch,

On Wed Nov 20, 2019 at 6:50 AM, Baruch Siach wrote:
> Hi Stephen, Stefan,
>
> 
> On Wed, Nov 20 2019, Stephen Brennan wrote:
>
> 
> > From: Stefan Wahren <wahrenst@gmx.net>
> >
> > The BCM2711 has a RNG200 block, so document its compatible string.
> >
> > Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
> > Signed-off-by: Stephen Brennan <stephen@brennan.io>
>
> 
> Isn't that duplicate of Florian's commit 6223949a1531?
>
> 
> > ---
> >  Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt b/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt
> > index c223e54452da..802523196ee5 100644
> > --- a/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt
> > +++ b/Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt
> > @@ -2,6 +2,7 @@ HWRNG support for the iproc-rng200 driver
> >  
> >  Required properties:
> >  - compatible : Must be one of:
> > +	       "brcm,bcm2711-rng200"
> >  	       "brcm,bcm7211-rng200"
>
> 
> Isn't this clear text duplication? Am I missing something obvious?
>

I understand the confusion, but they're different, we're looking at the 
difference between:

   bcm2711
   bcm7211
      ^^

These are apparently separate but related chips, leading to confusion in 
other places [1] as well. I double checked the commit 6223949a1531 you 
pointed out, as well as 1fa6d053b2a5 from your other email, to verify that 
this is the case. No duplication (as far as I can tell) is in the series.

[1]: https://github.com/raspberrypi/linux/issues/3163

Regards,
Stephen

> 
> I was looking at versions of this patch series wondering why no one
> noticed that.
>
> 
> baruch
>
> 
> >  	       "brcm,bcm7278-rng200"
> >  	       "brcm,iproc-rng200"
>
> 
> --
> http://baruch.siach.name/blog/ ~. .~ Tk Open Systems
> =}------------------------------------------------ooO--U--Ooo------------{=
> - baruch@tkos.co.il - tel: +972.52.368.4656, http://www.tkos.co.il -
>
> 
>
> 

Re: [PATCH v3 0/4] Raspberry Pi 4 HWRNG Support

[Stefan Wahren]

Hi Stephen,

Am 20.11.19 um 04:16 schrieb Stephen Brennan:
> This patch series enables support for the HWRNG included on the Raspberry
> Pi 4.  It is simply a rebase of Stefan's branch [1]. I went ahead and
> tested this out on a Pi 4.  Prior to this patch series, attempting to use
> the hwrng gives:
>
>     $ head -c 2 /dev/hwrng
>     head: /dev/hwrng: Input/output error
>
> After this series, the same command gives two random bytes.

just a note: a more expressive test would be running rngtest (package
rng-tools) on this device.

Regards
Stefan

Re: [PATCH v3 3/4] ARM: dts: bcm2835: Move rng definition to common location

[Stefan Wahren]

Am 20.11.19 um 04:16 schrieb Stephen Brennan:
> BCM2711 inherits from BCM283X, but has an incompatible HWRNG. Move this
> node to bcm2835-common.dtsi, so that BCM2711 can define its own.
>
> Signed-off-by: Stephen Brennan <stephen@brennan.io>
Acked-by: Stefan Wahren <wahrenst@gmx.net>

Re: [PATCH v3 4/4] ARM: dts: bcm2711: Enable HWRNG support

[Stefan Wahren]

Am 20.11.19 um 04:16 schrieb Stephen Brennan:
> This enables hardware random number generator support for the BCM2711
> on the Raspberry Pi 4 board.
>
> Signed-off-by: Stephen Brennan <stephen@brennan.io>

Acked-by: Stefan Wahren <wahrenst@gmx.net>

Thanks

Re: [PATCH v3 2/4] hwrng: iproc-rng200: Add support for BCM2711

[Matthias Brugger]

On 20/11/2019 05:52, Baruch Siach wrote:
> Hi Stephen, Stefan,
> 
> On Wed, Nov 20 2019, Stephen Brennan wrote:
>> From: Stefan Wahren <wahrenst@gmx.net>
>>
>> BCM2711 features a RNG200 hardware random number generator block.
>> So make the driver available.
>>
>> Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
>> Signed-off-by: Stephen Brennan <stephen@brennan.io>
>> Reviewed-by: Matthias Brugger <mbrugger@suse.com>
>> ---
>>  drivers/char/hw_random/Kconfig        | 2 +-
>>  drivers/char/hw_random/iproc-rng200.c | 1 +
>>  2 files changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
>> index 7c7fecfa2fb2..77e848fca531 100644
>> --- a/drivers/char/hw_random/Kconfig
>> +++ b/drivers/char/hw_random/Kconfig
>> @@ -90,7 +90,7 @@ config HW_RANDOM_BCM2835
>>  
>>  config HW_RANDOM_IPROC_RNG200
>>  	tristate "Broadcom iProc/STB RNG200 support"
>> -	depends on ARCH_BCM_IPROC || ARCH_BRCMSTB
>> +	depends on ARCH_BCM_IPROC || ARCH_BCM2835 || ARCH_BRCMSTB
>>  	default HW_RANDOM
>>  	---help---
>>  	  This driver provides kernel-side support for the RNG200
>> diff --git a/drivers/char/hw_random/iproc-rng200.c b/drivers/char/hw_random/iproc-rng200.c
>> index 899ff25f4f28..32d9fe61a225 100644
>> --- a/drivers/char/hw_random/iproc-rng200.c
>> +++ b/drivers/char/hw_random/iproc-rng200.c
>> @@ -213,6 +213,7 @@ static int iproc_rng200_probe(struct platform_device *pdev)
>>  }
>>  
>>  static const struct of_device_id iproc_rng200_of_match[] = {
>> +	{ .compatible = "brcm,bcm2711-rng200", },
>>  	{ .compatible = "brcm,bcm7211-rng200", },
> 
> Again, duplicate of commit 1fa6d053b2a5.
> 

That commit adds 7211 compatible while this patch adds one for 2711.

Regards,
Matthias

Re: [PATCH v3 4/4] ARM: dts: bcm2711: Enable HWRNG support

[Nicolas Saenz Julienne]

[-- Attachment #1: Type: text/plain, Size: 1018 bytes --]

On Tue, 2019-11-19 at 19:16 -0800, Stephen Brennan wrote:
> This enables hardware random number generator support for the BCM2711
> on the Raspberry Pi 4 board.
> 
> Signed-off-by: Stephen Brennan <stephen@brennan.io>
> ---
>  arch/arm/boot/dts/bcm2711.dtsi | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm/boot/dts/bcm2711.dtsi b/arch/arm/boot/dts/bcm2711.dtsi
> index ac83dac2e6ba..ed0877d5a1e9 100644
> --- a/arch/arm/boot/dts/bcm2711.dtsi
> +++ b/arch/arm/boot/dts/bcm2711.dtsi
> @@ -92,10 +92,9 @@ pm: watchdog@7e100000 {
>  		};
>  
>  		rng@7e104000 {
> -			interrupts = <GIC_SPI 125 IRQ_TYPE_LEVEL_HIGH>;
> -
> -			/* RNG is incompatible with brcm,bcm2835-rng */
> -			status = "disabled";
> +			compatible = "brcm,bcm2711-rng200";
> +			reg = <0x7e104000 0x28>;
> +			status = "okay";

Small nitpick, the 'okay' status is set by default, so no need for this. But
it's something we can edit out once we pick the patch.

Regards,
Nicolas


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Re: [PATCH v3 0/4] Raspberry Pi 4 HWRNG Support

[Nicolas Saenz Julienne]

[-- Attachment #1: Type: text/plain, Size: 1596 bytes --]

On Wed, 2019-11-20 at 17:16 +0100, Stefan Wahren wrote:
> Hi Stephen,
> 
> Am 20.11.19 um 04:16 schrieb Stephen Brennan:
> > This patch series enables support for the HWRNG included on the Raspberry
> > Pi 4.  It is simply a rebase of Stefan's branch [1]. I went ahead and
> > tested this out on a Pi 4.  Prior to this patch series, attempting to use
> > the hwrng gives:
> > 
> >     $ head -c 2 /dev/hwrng
> >     head: /dev/hwrng: Input/output error
> > 
> > After this series, the same command gives two random bytes.
> 
> just a note: a more expressive test would be running rngtest (package
> rng-tools) on this device.

Just had a go at it,

root@rpi4:~# rngtest -c 1000 < /dev/hwrng
rngtest 2-unofficial-mt.14
Copyright (c) 2004 by Henrique de Moraes Holschuh
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

rngtest: starting FIPS tests...
rngtest: bits received from input: 20000032
rngtest: FIPS 140-2 successes: 998
rngtest: FIPS 140-2 failures: 2
rngtest: FIPS 140-2(2001-10-10) Monobit: 0
rngtest: FIPS 140-2(2001-10-10) Poker: 1
rngtest: FIPS 140-2(2001-10-10) Runs: 0
rngtest: FIPS 140-2(2001-10-10) Long run: 1
rngtest: FIPS 140-2(2001-10-10) Continuous run: 0
rngtest: input channel speed: (min=1.284; avg=113.786; max=126.213)Kibits/s
rngtest: FIPS tests speed: (min=17.122; avg=28.268; max=28.812)Mibits/s
rngtest: Program run time: 172323761 microseconds

AFAIR (Arch wiki) some small failures are acceptable.

Regards,
Nicolas


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Re: [PATCH v3 1/4] dt-bindings: rng: add BCM2711 RNG compatible

[Florian Fainelli]

On 11/19/19 7:16 PM, Stephen Brennan wrote:
> From: Stefan Wahren <wahrenst@gmx.net>
> 
> The BCM2711 has a RNG200 block, so document its compatible string.
> 
> Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
> Signed-off-by: Stephen Brennan <stephen@brennan.io>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH v3 2/4] hwrng: iproc-rng200: Add support for BCM2711

[Florian Fainelli]

On 11/19/19 7:16 PM, Stephen Brennan wrote:
> From: Stefan Wahren <wahrenst@gmx.net>
> 
> BCM2711 features a RNG200 hardware random number generator block.
> So make the driver available.
> 
> Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
> Signed-off-by: Stephen Brennan <stephen@brennan.io>
> Reviewed-by: Matthias Brugger <mbrugger@suse.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH v3 0/4] Raspberry Pi 4 HWRNG Support

[Florian Fainelli]

Hi Herbert,

On 11/19/2019 7:16 PM, Stephen Brennan wrote:
> This patch series enables support for the HWRNG included on the Raspberry
> Pi 4.  It is simply a rebase of Stefan's branch [1]. I went ahead and
> tested this out on a Pi 4.  Prior to this patch series, attempting to use
> the hwrng gives:
> 
>     $ head -c 2 /dev/hwrng
>     head: /dev/hwrng: Input/output error
> 
> After this series, the same command gives two random bytes.

When we get a review from Rob, you can take patches 1-2 through your
tree and Stefan/Nicholas can queue patches 3-4 through the BCM2835 tree
where the DTS files already exist. Does that work for you?

> 
> Changes in v3:
> - drop interrupts from bcm2711 rng node
> - move bcm283x rng into bcm2835-common.dtsi
> - add reviewed-by tag
> - separated out patch 3 into two parts
> 
> Changes in v2:
> - specify the correct size for the region in the dts, refactor bcm283x rng
> 
> ---
> 
> Stefan Wahren (2):
>   dt-bindings: rng: add BCM2711 RNG compatible
>   hwrng: iproc-rng200: Add support for BCM2711
> 
> Stephen Brennan (2):
>   ARM: dts: bcm2835: Move rng definition to common location
>   ARM: dts: bcm2711: Enable HWRNG support
> 
>  .../devicetree/bindings/rng/brcm,iproc-rng200.txt          | 1 +
>  arch/arm/boot/dts/bcm2711.dtsi                             | 7 +++----
>  arch/arm/boot/dts/bcm2835-common.dtsi                      | 6 ++++++
>  arch/arm/boot/dts/bcm283x.dtsi                             | 6 ------
>  drivers/char/hw_random/Kconfig                             | 2 +-
>  drivers/char/hw_random/iproc-rng200.c                      | 1 +
>  6 files changed, 12 insertions(+), 11 deletions(-)
> 

-- 
Florian

Re: [PATCH v3 0/4] Raspberry Pi 4 HWRNG Support

[Herbert Xu]

On Wed, Nov 20, 2019 at 08:09:57PM -0800, Florian Fainelli wrote:
> Hi Herbert,
> 
> On 11/19/2019 7:16 PM, Stephen Brennan wrote:
> > This patch series enables support for the HWRNG included on the Raspberry
> > Pi 4.  It is simply a rebase of Stefan's branch [1]. I went ahead and
> > tested this out on a Pi 4.  Prior to this patch series, attempting to use
> > the hwrng gives:
> > 
> >     $ head -c 2 /dev/hwrng
> >     head: /dev/hwrng: Input/output error
> > 
> > After this series, the same command gives two random bytes.
> 
> When we get a review from Rob, you can take patches 1-2 through your
> tree and Stefan/Nicholas can queue patches 3-4 through the BCM2835 tree
> where the DTS files already exist. Does that work for you?

Yes sure.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

Re: [PATCH v3 0/4] Raspberry Pi 4 HWRNG Support

[Stefan Wahren]

Hi,

Am 20.11.19 um 20:50 schrieb Nicolas Saenz Julienne:
> On Wed, 2019-11-20 at 17:16 +0100, Stefan Wahren wrote:
>> Hi Stephen,
>>
>> Am 20.11.19 um 04:16 schrieb Stephen Brennan:
>>> This patch series enables support for the HWRNG included on the Raspberry
>>> Pi 4.  It is simply a rebase of Stefan's branch [1]. I went ahead and
>>> tested this out on a Pi 4.  Prior to this patch series, attempting to use
>>> the hwrng gives:
>>>
>>>     $ head -c 2 /dev/hwrng
>>>     head: /dev/hwrng: Input/output error
>>>
>>> After this series, the same command gives two random bytes.
>> just a note: a more expressive test would be running rngtest (package
>> rng-tools) on this device.
> Just had a go at it,
>
> root@rpi4:~# rngtest -c 1000 < /dev/hwrng
> rngtest 2-unofficial-mt.14
> Copyright (c) 2004 by Henrique de Moraes Holschuh
> This is free software; see the source for copying conditions.  There is NO
> warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
>
> rngtest: starting FIPS tests...
> rngtest: bits received from input: 20000032
> rngtest: FIPS 140-2 successes: 998
> rngtest: FIPS 140-2 failures: 2
> rngtest: FIPS 140-2(2001-10-10) Monobit: 0
> rngtest: FIPS 140-2(2001-10-10) Poker: 1
> rngtest: FIPS 140-2(2001-10-10) Runs: 0
> rngtest: FIPS 140-2(2001-10-10) Long run: 1
> rngtest: FIPS 140-2(2001-10-10) Continuous run: 0
> rngtest: input channel speed: (min=1.284; avg=113.786; max=126.213)Kibits/s
> rngtest: FIPS tests speed: (min=17.122; avg=28.268; max=28.812)Mibits/s
> rngtest: Program run time: 172323761 microseconds
>
> AFAIR (Arch wiki) some small failures are acceptable.
>
> Regards,
> Nicolas
>
thanks for the results. AFAIR the downstream implementation [1] has a
significant higher input speed. So there is possibly some room for
optimizations later.

Regards
Stefan

[1] -
https://github.com/raspberrypi/linux/commit/5e74aadfd1e0e6c00994521863ba044ce25b40de

Re: [PATCH v3 1/4] dt-bindings: rng: add BCM2711 RNG compatible

[Rob Herring]

On Tue, 19 Nov 2019 19:16:19 -0800, Stephen Brennan wrote:
> From: Stefan Wahren <wahrenst@gmx.net>
> 
> The BCM2711 has a RNG200 block, so document its compatible string.
> 
> Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
> Signed-off-by: Stephen Brennan <stephen@brennan.io>
> ---
>  Documentation/devicetree/bindings/rng/brcm,iproc-rng200.txt | 1 +
>  1 file changed, 1 insertion(+)
> 

Acked-by: Rob Herring <robh@kernel.org>

Re: [PATCH v3 0/4] Raspberry Pi 4 HWRNG Support

[Florian Fainelli]

On 11/20/2019 9:30 PM, Herbert Xu wrote:
> On Wed, Nov 20, 2019 at 08:09:57PM -0800, Florian Fainelli wrote:
>> Hi Herbert,
>>
>> On 11/19/2019 7:16 PM, Stephen Brennan wrote:
>>> This patch series enables support for the HWRNG included on the Raspberry
>>> Pi 4.  It is simply a rebase of Stefan's branch [1]. I went ahead and
>>> tested this out on a Pi 4.  Prior to this patch series, attempting to use
>>> the hwrng gives:
>>>
>>>     $ head -c 2 /dev/hwrng
>>>     head: /dev/hwrng: Input/output error
>>>
>>> After this series, the same command gives two random bytes.
>>
>> When we get a review from Rob, you can take patches 1-2 through your
>> tree and Stefan/Nicholas can queue patches 3-4 through the BCM2835 tree
>> where the DTS files already exist. Does that work for you?
> 
> Yes sure.

Rob has provided his Acked-by for the binding patch, are you targeting
these changes for 5.5 or 5.6 at this point?
-- 
Florian

Re: [PATCH v3 0/4] Raspberry Pi 4 HWRNG Support

[Herbert Xu]

On Tue, Dec 03, 2019 at 08:55:04PM -0800, Florian Fainelli wrote:
>
> Rob has provided his Acked-by for the binding patch, are you targeting
> these changes for 5.5 or 5.6 at this point?

They are too late for 5.5 so it's going to be 5.6.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt