[PATCH v3 0/5] hwrng: add support for i.MX6 rngb

[PATCH v3 0/5] hwrng: add support for i.MX6 rngb

[Horia Geantă]

Add support for RNGB found in some i.MX6 SoCs (6SL, 6SLL, 6ULL, 6ULZ),
based on RNGC driver (drivers/char/hw_random/imx-rngc.c).

This driver claims support also for RNGB (besides RNGC),
and is currently used only by i.MX25.

Note:

Several NXP SoC from QorIQ family (P1010, P1023, P4080, P3041, P5020)
also have a RNGB, however it's part of the CAAM
(Cryptograhic Accelerator and Assurance Module) crypto accelerator.
In this case, RNGB is managed in the caam driver
(drivers/crypto/caam/), since it's tightly related to
the caam "job ring" interface, not to mention CAAM internally relying on
RNGB as source of randomness.

On the other hand, the i.MX6 SoCs with RNGB have a DCP
(Data Co-Processor) crypto accelerator and this block and RNGB
are independent.

Changelog:
v3
-mention in the DT binding the compatibility with "fsl,imx25-rngb"
-collected Reviewed-by
v2
-update rngb DT binding with compatible strings for i.MX6 SoCs

Horia Geantă (5):
  dt-bindings: rng: add RNGB compatibles for i.MX6 SoCs
  ARM: dts: imx6sl: fix rng node
  ARM: dts: imx6sll: add rng
  ARM: dts: imx6ull: add rng
  hwrng: imx-rngc: enable driver for i.MX6

 Documentation/devicetree/bindings/rng/imx-rng.txt | 3 +++
 arch/arm/boot/dts/imx6sl.dtsi                     | 2 ++
 arch/arm/boot/dts/imx6sll.dtsi                    | 7 +++++++
 arch/arm/boot/dts/imx6ull.dtsi                    | 7 +++++++
 drivers/char/hw_random/Kconfig                    | 2 +-
 drivers/char/hw_random/imx-rngc.c                 | 3 +++
 6 files changed, 23 insertions(+), 1 deletion(-)

-- 
2.17.1

[PATCH v3 1/5] dt-bindings: rng: add RNGB compatibles for i.MX6 SoCs

[Horia Geantă]

RNGB block is found in some i.MX6 SoCs - 6SL, 6SLL, 6ULL, 6ULZ.
Add corresponding compatible strings.

Note:

Several NXP SoC from QorIQ family (P1010, P1023, P4080, P3041, P5020)
also have a RNGB, however it's part of the CAAM
(Cryptograhic Accelerator and Assurance Module) crypto accelerator.
In this case, RNGB is managed in the caam driver
(drivers/crypto/caam/), since it's tightly related to
the caam "job ring" interface, not to mention CAAM internally relying on
RNGB as source of randomness.

On the other hand, the i.MX6 SoCs with RNGB have a DCP
(Data Co-Processor) crypto accelerator and this block and RNGB
are independent.

Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
---
 Documentation/devicetree/bindings/rng/imx-rng.txt | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/rng/imx-rng.txt b/Documentation/devicetree/bindings/rng/imx-rng.txt
index 405c2b00ccb0..659d4efdd664 100644
--- a/Documentation/devicetree/bindings/rng/imx-rng.txt
+++ b/Documentation/devicetree/bindings/rng/imx-rng.txt
@@ -5,6 +5,9 @@ Required properties:
                "fsl,imx21-rnga"
                "fsl,imx31-rnga" (backward compatible with "fsl,imx21-rnga")
                "fsl,imx25-rngb"
+               "fsl,imx6sl-rngb" (backward compatible with "fsl,imx25-rngb")
+               "fsl,imx6sll-rngb" (backward compatible with "fsl,imx25-rngb")
+               "fsl,imx6ull-rngb" (backward compatible with "fsl,imx25-rngb")
                "fsl,imx35-rngc"
 - reg : offset and length of the register set of this block
 - interrupts : the interrupt number for the RNG block
-- 
2.17.1

Re: [PATCH v3 1/5] dt-bindings: rng: add RNGB compatibles for i.MX6 SoCs

[Rob Herring]

On Tue, 14 Jul 2020 15:39:16 +0300, Horia Geantă wrote:
> RNGB block is found in some i.MX6 SoCs - 6SL, 6SLL, 6ULL, 6ULZ.
> Add corresponding compatible strings.
> 
> Note:
> 
> Several NXP SoC from QorIQ family (P1010, P1023, P4080, P3041, P5020)
> also have a RNGB, however it's part of the CAAM
> (Cryptograhic Accelerator and Assurance Module) crypto accelerator.
> In this case, RNGB is managed in the caam driver
> (drivers/crypto/caam/), since it's tightly related to
> the caam "job ring" interface, not to mention CAAM internally relying on
> RNGB as source of randomness.
> 
> On the other hand, the i.MX6 SoCs with RNGB have a DCP
> (Data Co-Processor) crypto accelerator and this block and RNGB
> are independent.
> 
> Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
> ---
>  Documentation/devicetree/bindings/rng/imx-rng.txt | 3 +++
>  1 file changed, 3 insertions(+)
> 

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

[PATCH v3 2/5] ARM: dts: imx6sl: fix rng node

[Horia Geantă]

rng DT node was added without a compatible string.

i.MX driver for RNGC (drivers/char/hw_random/imx-rngc.c) also claims
support for RNGB, and is currently used for i.MX25.

Let's use this driver also for RNGB block in i.MX6SL.

Fixes: e29fe21cff96 ("ARM: dts: add device tree source for imx6sl SoC")
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
---
 arch/arm/boot/dts/imx6sl.dtsi | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/boot/dts/imx6sl.dtsi b/arch/arm/boot/dts/imx6sl.dtsi
index 1c7180f28539..91a8c54d5e11 100644
--- a/arch/arm/boot/dts/imx6sl.dtsi
+++ b/arch/arm/boot/dts/imx6sl.dtsi
@@ -939,8 +939,10 @@
 			};
 
 			rngb: rngb@21b4000 {
+				compatible = "fsl,imx6sl-rngb", "fsl,imx25-rngb";
 				reg = <0x021b4000 0x4000>;
 				interrupts = <0 5 IRQ_TYPE_LEVEL_HIGH>;
+				clocks = <&clks IMX6SL_CLK_DUMMY>;
 			};
 
 			weim: weim@21b8000 {
-- 
2.17.1

[PATCH v3 3/5] ARM: dts: imx6sll: add rng

[Horia Geantă]

Add node for the RNGB block.

Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
---
 arch/arm/boot/dts/imx6sll.dtsi | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm/boot/dts/imx6sll.dtsi b/arch/arm/boot/dts/imx6sll.dtsi
index fb5d3bc50c6b..0b622201a1f3 100644
--- a/arch/arm/boot/dts/imx6sll.dtsi
+++ b/arch/arm/boot/dts/imx6sll.dtsi
@@ -786,6 +786,13 @@
 				clocks = <&clks IMX6SLL_CLK_MMDC_P0_IPG>;
 			};
 
+			rngb: rng@21b4000 {
+				compatible = "fsl,imx6sll-rngb", "fsl,imx25-rngb";
+				reg = <0x021b4000 0x4000>;
+				interrupts = <GIC_SPI 5 IRQ_TYPE_LEVEL_HIGH>;
+				clocks = <&clks IMX6SLL_CLK_DUMMY>;
+			};
+
 			ocotp: efuse@21bc000 {
 				#address-cells = <1>;
 				#size-cells = <1>;
-- 
2.17.1

[PATCH v3 4/5] ARM: dts: imx6ull: add rng

[Horia Geantă]

Add node for the RNGB block.

Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Reviewed-by: Marco Felsch <m.felsch@pengutronix.de>
---
 arch/arm/boot/dts/imx6ull.dtsi | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm/boot/dts/imx6ull.dtsi b/arch/arm/boot/dts/imx6ull.dtsi
index fcde7f77ae42..9bf67490ac49 100644
--- a/arch/arm/boot/dts/imx6ull.dtsi
+++ b/arch/arm/boot/dts/imx6ull.dtsi
@@ -68,6 +68,13 @@
 				clock-names = "dcp";
 			};
 
+			rngb: rng@2284000 {
+				compatible = "fsl,imx6ull-rngb", "fsl,imx25-rngb";
+				reg = <0x02284000 0x4000>;
+				interrupts = <GIC_SPI 6 IRQ_TYPE_LEVEL_HIGH>;
+				clocks = <&clks IMX6UL_CLK_DUMMY>;
+			};
+
 			iomuxc_snvs: iomuxc-snvs@2290000 {
 				compatible = "fsl,imx6ull-iomuxc-snvs";
 				reg = <0x02290000 0x4000>;
-- 
2.17.1

[PATCH v3 5/5] hwrng: imx-rngc: enable driver for i.MX6

[Horia Geantă]

i.MX6 SL, SLL, ULL, ULZ SoCs have an RNGB block.

Since imx-rngc driver supports also rngb,
let's enable it for these SoCs too.

Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Reviewed-by: Martin Kaiser <martin@kaiser.cx>
Reviewed-by: Marco Felsch <m.felsch@pengutronix.de>
---
 drivers/char/hw_random/Kconfig    | 2 +-
 drivers/char/hw_random/imx-rngc.c | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 8478eb757f3c..98f95a09ce55 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -255,7 +255,7 @@ config HW_RANDOM_MXC_RNGA
 config HW_RANDOM_IMX_RNGC
 	tristate "Freescale i.MX RNGC Random Number Generator"
 	depends on HAS_IOMEM && HAVE_CLK
-	depends on SOC_IMX25 || COMPILE_TEST
+	depends on SOC_IMX25 || SOC_IMX6SL || SOC_IMX6SLL || SOC_IMX6UL || COMPILE_TEST
 	default HW_RANDOM
 	help
 	  This driver provides kernel-side support for the Random Number
diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
index 9c47e431ce90..84576d2fbf8c 100644
--- a/drivers/char/hw_random/imx-rngc.c
+++ b/drivers/char/hw_random/imx-rngc.c
@@ -350,6 +350,9 @@ static SIMPLE_DEV_PM_OPS(imx_rngc_pm_ops, imx_rngc_suspend, imx_rngc_resume);
 
 static const struct of_device_id imx_rngc_dt_ids[] = {
 	{ .compatible = "fsl,imx25-rngb", .data = NULL, },
+	{ .compatible = "fsl,imx6sl-rngb", .data = NULL, },
+	{ .compatible = "fsl,imx6sll-rngb", .data = NULL, },
+	{ .compatible = "fsl,imx6ull-rngb", .data = NULL, },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, imx_rngc_dt_ids);
-- 
2.17.1

Re: [PATCH v3 5/5] hwrng: imx-rngc: enable driver for i.MX6

[Arnd Bergmann]

On Tue, Jul 14, 2020 at 2:39 PM Horia Geantă <horia.geanta@nxp.com> wrote:
> diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
> index 8478eb757f3c..98f95a09ce55 100644
> --- a/drivers/char/hw_random/Kconfig
> +++ b/drivers/char/hw_random/Kconfig
> @@ -255,7 +255,7 @@ config HW_RANDOM_MXC_RNGA
>  config HW_RANDOM_IMX_RNGC
>         tristate "Freescale i.MX RNGC Random Number Generator"
>         depends on HAS_IOMEM && HAVE_CLK
> -       depends on SOC_IMX25 || COMPILE_TEST
> +       depends on SOC_IMX25 || SOC_IMX6SL || SOC_IMX6SLL || SOC_IMX6UL || COMPILE_TEST
>         default HW_RANDOM

Are these the only chips that have it? If other i.MX variations have
the same block,
or might have it in the future, maybe just generialize the dependency
to SOC_IMX6
or ARCH_IMX?

> diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
> index 9c47e431ce90..84576d2fbf8c 100644
> --- a/drivers/char/hw_random/imx-rngc.c
> +++ b/drivers/char/hw_random/imx-rngc.c
> @@ -350,6 +350,9 @@ static SIMPLE_DEV_PM_OPS(imx_rngc_pm_ops, imx_rngc_suspend, imx_rngc_resume);
>
>  static const struct of_device_id imx_rngc_dt_ids[] = {
>         { .compatible = "fsl,imx25-rngb", .data = NULL, },
> +       { .compatible = "fsl,imx6sl-rngb", .data = NULL, },
> +       { .compatible = "fsl,imx6sll-rngb", .data = NULL, },
> +       { .compatible = "fsl,imx6ull-rngb", .data = NULL, },
>         { /* sentinel */ }

In the .dts file you describe the devices as compatible with fsl,imx25-rngb,
so this change is not really needed, unless you want to add non-NULL
.data fields in a follow-up. It is usually a good idea to have the more
specialized compatible strings in the DT, but the driver change won't
do anything here.

       Arnd

Re: [PATCH v3 5/5] hwrng: imx-rngc: enable driver for i.MX6

[Horia Geantă]

On 7/14/2020 3:48 PM, Arnd Bergmann wrote:
> On Tue, Jul 14, 2020 at 2:39 PM Horia Geantă <horia.geanta@nxp.com> wrote:
>> diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
>> index 8478eb757f3c..98f95a09ce55 100644
>> --- a/drivers/char/hw_random/Kconfig
>> +++ b/drivers/char/hw_random/Kconfig
>> @@ -255,7 +255,7 @@ config HW_RANDOM_MXC_RNGA
>>  config HW_RANDOM_IMX_RNGC
>>         tristate "Freescale i.MX RNGC Random Number Generator"
>>         depends on HAS_IOMEM && HAVE_CLK
>> -       depends on SOC_IMX25 || COMPILE_TEST
>> +       depends on SOC_IMX25 || SOC_IMX6SL || SOC_IMX6SLL || SOC_IMX6UL || COMPILE_TEST
>>         default HW_RANDOM
> 
> Are these the only chips that have it? If other i.MX variations have
> the same block,
> or might have it in the future, maybe just generialize the dependency
> to SOC_IMX6
> or ARCH_IMX?
> 
Fabio also suggested this during v1, see discussion here:
https://lore.kernel.org/linux-crypto/292aafd1-7249-5b76-ccc3-77b153594ef9@nxp.com

The SoC list is relatively stable, to the best of my knowledge.

>> diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
>> index 9c47e431ce90..84576d2fbf8c 100644
>> --- a/drivers/char/hw_random/imx-rngc.c
>> +++ b/drivers/char/hw_random/imx-rngc.c
>> @@ -350,6 +350,9 @@ static SIMPLE_DEV_PM_OPS(imx_rngc_pm_ops, imx_rngc_suspend, imx_rngc_resume);
>>
>>  static const struct of_device_id imx_rngc_dt_ids[] = {
>>         { .compatible = "fsl,imx25-rngb", .data = NULL, },
>> +       { .compatible = "fsl,imx6sl-rngb", .data = NULL, },
>> +       { .compatible = "fsl,imx6sll-rngb", .data = NULL, },
>> +       { .compatible = "fsl,imx6ull-rngb", .data = NULL, },
>>         { /* sentinel */ }
> 
> In the .dts file you describe the devices as compatible with fsl,imx25-rngb,
> so this change is not really needed, unless you want to add non-NULL
> .data fields in a follow-up. It is usually a good idea to have the more
> specialized compatible strings in the DT, but the driver change won't
> do anything here.
> 
Indeed, this isn't needed.
Will remove it in v4.

Thanks,
Horia

Re: [PATCH v3 5/5] hwrng: imx-rngc: enable driver for i.MX6

[Fabio Estevam]

On Tue, Jul 14, 2020 at 9:39 AM Horia Geantă <horia.geanta@nxp.com> wrote:

>  static const struct of_device_id imx_rngc_dt_ids[] = {
>         { .compatible = "fsl,imx25-rngb", .data = NULL, },
> +       { .compatible = "fsl,imx6sl-rngb", .data = NULL, },
> +       { .compatible = "fsl,imx6sll-rngb", .data = NULL, },
> +       { .compatible = "fsl,imx6ull-rngb", .data = NULL, },

It seems that these new entries are not needed, since they fallback to
"fsl,imx25-rngb".