[PATCH v2 0/3] hw_random: Add Amlogic Meson SoCs Random Generator driver

[PATCH v2 0/3] hw_random: Add Amlogic Meson SoCs Random Generator driver

[Neil Armstrong]

Add support for the Amlogic Meson SoCs Hardware Random generator as a hw_random char driver.
The generator is a single 32bit wide register.
Also adds the Meson GXBB SoC DTSI node and corresponding DT bindings.

Changes since v1 at http://lkml.kernel.org/r/1464943621-18278-1-git-send-email-narmstrong@baylibre.com :
- change to depend on ARCH_MESON || COMPILE_TEST
- check buffer max size in read

Neil Armstrong (3):
  char: hw_random: Add Amlogic Meson Hardware Random Generator
  dt-bindings: hwrng: Add Amlogic Meson Hardware Random Generator
    bindings
  ARM64: dts: meson-gxbb: Add Hardware Random Generator node

 .../devicetree/bindings/rng/amlogic,meson-rng.txt  |  14 +++
 arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi        |   5 +
 drivers/char/hw_random/Kconfig                     |  14 +++
 drivers/char/hw_random/Makefile                    |   1 +
 drivers/char/hw_random/meson-rng.c                 | 131 +++++++++++++++++++++
 5 files changed, 165 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/rng/amlogic,meson-rng.txt
 create mode 100644 drivers/char/hw_random/meson-rng.c

-- 
2.7.0

[PATCH v2 1/3] char: hw_random: Add Amlogic Meson Hardware Random Generator

[Neil Armstrong]

Add support for the Amlogic Meson SoCs hardware random generator.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
 drivers/char/hw_random/Kconfig     |  14 ++++
 drivers/char/hw_random/Makefile    |   1 +
 drivers/char/hw_random/meson-rng.c | 131 +++++++++++++++++++++++++++++++++++++
 3 files changed, 146 insertions(+)
 create mode 100644 drivers/char/hw_random/meson-rng.c

diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index ac51149..8558a61 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -396,6 +396,20 @@ config HW_RANDOM_PIC32
 
 	  If unsure, say Y.
 
+config HW_RANDOM_MESON
+	tristate "Amlogic Meson Random Number Generator support"
+	depends on HW_RANDOM
+	depends on ARCH_MESON || COMPILE_TEST
+	default y
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on Amlogic Meson SoCs.
+
+	  To compile this driver as a module, choose M here. the
+	  module will be called meson-rng.
+
+	  If unsure, say Y.
+
 endif # HW_RANDOM
 
 config UML_RANDOM
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index 63022b4..04bb0b0 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -34,3 +34,4 @@ obj-$(CONFIG_HW_RANDOM_ST) += st-rng.o
 obj-$(CONFIG_HW_RANDOM_XGENE) += xgene-rng.o
 obj-$(CONFIG_HW_RANDOM_STM32) += stm32-rng.o
 obj-$(CONFIG_HW_RANDOM_PIC32) += pic32-rng.o
+obj-$(CONFIG_HW_RANDOM_MESON) += meson-rng.o
diff --git a/drivers/char/hw_random/meson-rng.c b/drivers/char/hw_random/meson-rng.c
new file mode 100644
index 0000000..0cfd81b
--- /dev/null
+++ b/drivers/char/hw_random/meson-rng.c
@@ -0,0 +1,131 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright (c) 2016 BayLibre, SAS.
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ * Copyright (C) 2014 Amlogic, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ * The full GNU General Public License is included in this distribution
+ * in the file called COPYING.
+ *
+ * BSD LICENSE
+ *
+ * Copyright (c) 2016 BayLibre, SAS.
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ * Copyright (C) 2014 Amlogic, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in
+ *     the documentation and/or other materials provided with the
+ *     distribution.
+ *   * Neither the name of Intel Corporation nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/hw_random.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/of.h>
+
+#define RNG_DATA 0x00
+
+struct meson_rng_data {
+	void __iomem *base;
+	struct platform_device *pdev;
+	struct hwrng rng;
+};
+
+static int meson_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
+{
+	struct meson_rng_data *data =
+			container_of(rng, struct meson_rng_data, rng);
+
+	if (max < sizeof(u32))
+		return 0;
+
+	*(u32 *)buf = readl_relaxed(data->base + RNG_DATA);
+
+	return sizeof(u32);
+}
+
+static int meson_rng_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct meson_rng_data *data;
+	struct resource *res;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->pdev = pdev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	data->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(data->base))
+		return PTR_ERR(data->base);
+
+	data->rng.name = pdev->name;
+	data->rng.read = meson_rng_read;
+
+	platform_set_drvdata(pdev, data);
+
+	return devm_hwrng_register(dev, &data->rng);
+}
+
+static const struct of_device_id meson_rng_of_match[] = {
+	{ .compatible = "amlogic,meson-rng", },
+	{},
+};
+
+static struct platform_driver meson_rng_driver = {
+	.probe	= meson_rng_probe,
+	.driver	= {
+		.name = "meson-rng",
+		.of_match_table = meson_rng_of_match,
+	},
+};
+
+module_platform_driver(meson_rng_driver);
+
+MODULE_ALIAS("platform:meson-rng");
+MODULE_DESCRIPTION("Meson H/W Random Number Generator driver");
+MODULE_AUTHOR("Lawrence Mok <lawrence.mok@amlogic.com>");
+MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
+MODULE_LICENSE("Dual BSD/GPL");
-- 
2.7.0

[PATCH v2 2/3] dt-bindings: hwrng: Add Amlogic Meson Hardware Random Generator bindings

[Neil Armstrong]

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
 .../devicetree/bindings/rng/amlogic,meson-rng.txt          | 14 ++++++++++++++
 1 file changed, 14 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/rng/amlogic,meson-rng.txt

diff --git a/Documentation/devicetree/bindings/rng/amlogic,meson-rng.txt b/Documentation/devicetree/bindings/rng/amlogic,meson-rng.txt
new file mode 100644
index 0000000..202f2d0
--- /dev/null
+++ b/Documentation/devicetree/bindings/rng/amlogic,meson-rng.txt
@@ -0,0 +1,14 @@
+Amlogic Meson Random number generator
+=====================================
+
+Required properties:
+
+- compatible : should be "amlogic,meson-rng"
+- reg : Specifies base physical address and size of the registers.
+
+Example:
+
+rng {
+        compatible = "amlogic,meson-rng";
+        reg = <0x0 0xc8834000 0x0 0x4>;
+};
-- 
2.7.0

[PATCH v2 3/3] ARM64: dts: meson-gxbb: Add Hardware Random Generator node

[Neil Armstrong]

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
 arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
index 832815d..8353621 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
@@ -167,6 +167,11 @@
 			};
 		};
 
+		rng {
+			compatible = "amlogic,meson-rng";
+			reg = <0x0 0xc8834000 0x0 0x4>;
+		};
+
 		apb: apb@d0000000 {
 			compatible = "simple-bus";
 			reg = <0x0 0xd0000000 0x0 0x200000>;
-- 
2.7.0

Re: [PATCH v2 0/3] hw_random: Add Amlogic Meson SoCs Random Generator driver

[Herbert Xu]

On Fri, Jun 10, 2016 at 10:21:52AM +0200, Neil Armstrong wrote:
> Add support for the Amlogic Meson SoCs Hardware Random generator as a hw_random char driver.
> The generator is a single 32bit wide register.
> Also adds the Meson GXBB SoC DTSI node and corresponding DT bindings.
> 
> Changes since v1 at http://lkml.kernel.org/r/1464943621-18278-1-git-send-email-narmstrong@baylibre.com :
> - change to depend on ARCH_MESON || COMPILE_TEST
> - check buffer max size in read
> 
> Neil Armstrong (3):
>   char: hw_random: Add Amlogic Meson Hardware Random Generator
>   dt-bindings: hwrng: Add Amlogic Meson Hardware Random Generator
>     bindings
>   ARM64: dts: meson-gxbb: Add Hardware Random Generator node

All applied.  Thanks.
-- 
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 v2 3/3] ARM64: dts: meson-gxbb: Add Hardware Random Generator node

[Kevin Hilman]

Hi Neil,

Neil Armstrong <narmstrong@baylibre.com> writes:

> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
> ---
>  arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
> index 832815d..8353621 100644
> --- a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
> +++ b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
> @@ -167,6 +167,11 @@
>  			};
>  		};
>  
> +		rng {
> +			compatible = "amlogic,meson-rng";
> +			reg = <0x0 0xc8834000 0x0 0x4>;
> +		};

This should be under the periphs bus, with an offset of 0x0 instead of
at the top level.

See the for-next branch in the linux-amlogic tree[1] which has separate
busses for periphs and hiu.

Kevin

[1] git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-amlogic.git

Re: [PATCH v2 0/3] hw_random: Add Amlogic Meson SoCs Random Generator driver

[Kevin Hilman]

Hi Herbert,

Herbert Xu <herbert@gondor.apana.org.au> writes:

> On Fri, Jun 10, 2016 at 10:21:52AM +0200, Neil Armstrong wrote:
>> Add support for the Amlogic Meson SoCs Hardware Random generator as a hw_random char driver.
>> The generator is a single 32bit wide register.
>> Also adds the Meson GXBB SoC DTSI node and corresponding DT bindings.
>> 
>> Changes since v1 at http://lkml.kernel.org/r/1464943621-18278-1-git-send-email-narmstrong@baylibre.com :
>> - change to depend on ARCH_MESON || COMPILE_TEST
>> - check buffer max size in read
>> 
>> Neil Armstrong (3):
>>   char: hw_random: Add Amlogic Meson Hardware Random Generator
>>   dt-bindings: hwrng: Add Amlogic Meson Hardware Random Generator
>>     bindings
>>   ARM64: dts: meson-gxbb: Add Hardware Random Generator node
>
> All applied.  Thanks.

Could you take just the driver please?

Due to lots of other activity in the DT, I'd prefer to send the DT &
bindings though the arm-soc (via the amlogic tree.)

Thanks,

Kevin

Re: [PATCH v2 3/3] ARM64: dts: meson-gxbb: Add Hardware Random Generator node

[Neil Armstrong]

On 06/14/2016 12:09 AM, Kevin Hilman wrote:
> Hi Neil,
> 
> Neil Armstrong <narmstrong@baylibre.com> writes:
> 
>> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
>> ---
>>  arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi | 5 +++++
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
>> index 832815d..8353621 100644
>> --- a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
>> +++ b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
>> @@ -167,6 +167,11 @@
>>  			};
>>  		};
>>  
>> +		rng {
>> +			compatible = "amlogic,meson-rng";
>> +			reg = <0x0 0xc8834000 0x0 0x4>;
>> +		};
> 
> This should be under the periphs bus, with an offset of 0x0 instead of
> at the top level.
> 
> See the for-next branch in the linux-amlogic tree[1] which has separate
> busses for periphs and hiu.

Yes, It was introduced lately.

Herbert,

I'll repost this patch separately to arm-soc directly rebased on [1].

Thanks,
Neil

> Kevin
> 
> [1] git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-amlogic.git
> 

Re: [PATCH v2 0/3] hw_random: Add Amlogic Meson SoCs Random Generator driver

[Herbert Xu]

On Mon, Jun 13, 2016 at 03:10:28PM -0700, Kevin Hilman wrote:
> Could you take just the driver please?
> 
> Due to lots of other activity in the DT, I'd prefer to send the DT &
> bindings though the arm-soc (via the amlogic tree.)

OK I will back out these two patches.

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