This patch series adds support of pseudo random number generator found
in Ingenic's JZ4780 and X1000 SoC.
Based on Paul's review comments, add 'syscon' compatible in CGU node in
jz4780.dtsi. jz4780-rng driver uses regmap exposed via syscon interface
to access the RNG registers. CGU driver is not modified in this patch
set as registers used by CGU driver and this driver are different.
PrasannaKumar Muralidharan (4):
crypto: jz4780-rng: Add JZ4780 PRNG devicetree binding documentation
crypto: jz4780-rng: Add Ingenic JZ4780 hardware PRNG driver
crypto: jz4780-rng: Add RNG node to jz4780.dtsi
crypto: jz4780-rng: Enable PRNG support in CI20 defconfig
.../bindings/crypto/ingenic,jz4780-rng.txt | 20 +++
MAINTAINERS | 5 +
arch/mips/boot/dts/ingenic/jz4780.dtsi | 6 +-
arch/mips/configs/ci20_defconfig | 5 +
drivers/crypto/Kconfig | 19 +++
drivers/crypto/Makefile | 1 +
drivers/crypto/jz4780-rng.c | 168 +++++++++++++++++++++
7 files changed, 223 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
create mode 100644 drivers/crypto/jz4780-rng.c
--
2.10.0
Add devicetree bindings for hardware pseudo random number generator
present in Ingenic JZ4780 SoC.
Signed-off-by: PrasannaKumar Muralidharan <[email protected]>
---
Changes in v2:
* Add "syscon" in CGU node's compatible section
* Make RNG child node of CGU.
.../bindings/crypto/ingenic,jz4780-rng.txt | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
create mode 100644 Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
diff --git a/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt b/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
new file mode 100644
index 0000000..a0c18e5
--- /dev/null
+++ b/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
@@ -0,0 +1,20 @@
+Ingenic jz4780 RNG driver
+
+Required properties:
+- compatible : Should be "ingenic,jz4780-rng"
+
+Example:
+
+cgu: jz4780-cgu@10000000 {
+ compatible = "ingenic,jz4780-cgu", "syscon";
+ reg = <0x10000000 0x100>;
+
+ clocks = <&ext>, <&rtc>;
+ clock-names = "ext", "rtc";
+
+ #clock-cells = <1>;
+
+ rng: rng@d8 {
+ compatible = "ingenic,jz480-rng";
+ };
+};
--
2.10.0
JZ4780 SoC pseudo random number generator driver using crypto framework.
Adding a delay before reading RNG data and disabling RNG after reading
data was suggested by Jeffery Walton.
Tested-by: Mathieu Malaterre <[email protected]>
Suggested-by: Jeffrey Walton <[email protected]>
Signed-off-by: PrasannaKumar Muralidharan <[email protected]>
---
Changes in v2:
* Fixed buffer overflow in generate function pointed out in Stephan's review
* Fold patch that had only MAINTAINERS file change with this patch
* Removed unnecessary comment in code
MAINTAINERS | 5 ++
drivers/crypto/Kconfig | 19 +++++
drivers/crypto/Makefile | 1 +
drivers/crypto/jz4780-rng.c | 168 ++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 193 insertions(+)
create mode 100644 drivers/crypto/jz4780-rng.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 1c3feff..f662a70 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6672,6 +6672,11 @@ L: [email protected]
S: Maintained
F: drivers/mtd/nand/jz4780_*
+INGENIC JZ4780 PRNG DRIVER
+M: PrasannaKumar Muralidharan <[email protected]>
+S: Maintained
+F: drivers/crypto/jz4780-rng.c
+
INOTIFY
M: John McCutchan <[email protected]>
M: Robert Love <[email protected]>
diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index 4b75084..de2459f 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -599,6 +599,25 @@ config CRYPTO_DEV_IMGTEC_HASH
hardware hash accelerator. Supporting MD5/SHA1/SHA224/SHA256
hashing algorithms.
+config CRYPTO_DEV_JZ4780_RNG
+ tristate "JZ4780 HW pseudo random number generator support"
+ depends on MACH_JZ4780 || COMPILE_TEST
+ depends on HAS_IOMEM
+ select CRYPTO_RNG
+ select REGMAP
+ select SYSCON
+ select MFD_SYSCON
+ ---help---
+ This driver provides kernel-side support through the
+ cryptographic API for the pseudo random number generator
+ hardware found in ingenic JZ4780 and X1000 SoC. MIPS
+ Creator CI20 uses JZ4780 SoC.
+
+ To compile this driver as a module, choose M here: the
+ module will be called jz4780-rng.
+
+ If unsure, say Y.
+
config CRYPTO_DEV_SUN4I_SS
tristate "Support for Allwinner Security System cryptographic accelerator"
depends on ARCH_SUNXI && !64BIT
diff --git a/drivers/crypto/Makefile b/drivers/crypto/Makefile
index 2c555a3..1df48f9 100644
--- a/drivers/crypto/Makefile
+++ b/drivers/crypto/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_CRYPTO_DEV_GEODE) += geode-aes.o
obj-$(CONFIG_CRYPTO_DEV_HIFN_795X) += hifn_795x.o
obj-$(CONFIG_CRYPTO_DEV_IMGTEC_HASH) += img-hash.o
obj-$(CONFIG_CRYPTO_DEV_IXP4XX) += ixp4xx_crypto.o
+obj-$(CONFIG_CRYPTO_DEV_JZ4780_RNG) += jz4780-rng.o
obj-$(CONFIG_CRYPTO_DEV_MV_CESA) += mv_cesa.o
obj-$(CONFIG_CRYPTO_DEV_MARVELL_CESA) += marvell/
obj-$(CONFIG_CRYPTO_DEV_MEDIATEK) += mediatek/
diff --git a/drivers/crypto/jz4780-rng.c b/drivers/crypto/jz4780-rng.c
new file mode 100644
index 0000000..4444682
--- /dev/null
+++ b/drivers/crypto/jz4780-rng.c
@@ -0,0 +1,168 @@
+/*
+ * jz4780-rng.c - Random Number Generator driver for the jz4780
+ *
+ * Copyright (c) 2017 PrasannaKumar Muralidharan <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms 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.
+ */
+
+#include <linux/crypto.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include <crypto/internal/rng.h>
+
+#define REG_RNG_CTRL 0xD8
+#define REG_RNG_DATA 0xDC
+
+/* Context for crypto */
+struct jz4780_rng_ctx {
+ struct jz4780_rng *rng;
+};
+
+/* Device associated memory */
+struct jz4780_rng {
+ struct device *dev;
+ struct regmap *regmap;
+};
+
+static struct jz4780_rng *jz4780_rng;
+
+static int jz4780_rng_readl(struct jz4780_rng *rng, u32 offset)
+{
+ u32 val = 0;
+ int ret;
+
+ ret = regmap_read(rng->regmap, offset, &val);
+ if (!ret)
+ return val;
+
+ return ret;
+}
+
+static int jz4780_rng_writel(struct jz4780_rng *rng, u32 val, u32 offset)
+{
+ return regmap_write(rng->regmap, offset, val);
+}
+
+static int jz4780_rng_generate(struct crypto_rng *tfm,
+ const u8 *src, unsigned int slen,
+ u8 *dst, unsigned int dlen)
+{
+ struct jz4780_rng_ctx *ctx = crypto_rng_ctx(tfm);
+ struct jz4780_rng *rng = ctx->rng;
+ u32 data;
+
+ /*
+ * A delay is required so that the current RNG data is not bit shifted
+ * version of previous RNG data which could happen if random data is
+ * read continuously from this device.
+ */
+ jz4780_rng_writel(rng, 1, REG_RNG_CTRL);
+ while (dlen >= 4) {
+ data = jz4780_rng_readl(rng, REG_RNG_DATA);
+ memcpy((void *)dst, (void *)&data, 4);
+ dlen -= 4;
+ dst += 4;
+ udelay(20);
+ };
+
+ if (dlen > 0) {
+ data = jz4780_rng_readl(rng, REG_RNG_DATA);
+ memcpy((void *)dst, (void *)&data, dlen);
+ }
+ jz4780_rng_writel(rng, 0, REG_RNG_CTRL);
+
+ return 0;
+}
+
+static int jz4780_rng_kcapi_init(struct crypto_tfm *tfm)
+{
+ struct jz4780_rng_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ ctx->rng = jz4780_rng;
+
+ return 0;
+}
+
+static struct rng_alg jz4780_rng_alg = {
+ .generate = jz4780_rng_generate,
+ .base = {
+ .cra_name = "stdrng",
+ .cra_driver_name = "jz4780_rng",
+ .cra_priority = 100,
+ .cra_ctxsize = sizeof(struct jz4780_rng_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_init = jz4780_rng_kcapi_init,
+ }
+};
+
+static int jz4780_rng_probe(struct platform_device *pdev)
+{
+ struct jz4780_rng *rng;
+ struct resource *res;
+ int ret;
+
+ rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
+ if (!rng)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ rng->regmap = syscon_node_to_regmap(pdev->dev.parent->of_node);
+ if (IS_ERR(rng->regmap))
+ return PTR_ERR(rng->regmap);
+
+ jz4780_rng = rng;
+
+ ret = crypto_register_rng(&jz4780_rng_alg);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Couldn't register rng crypto alg: %d\n", ret);
+ jz4780_rng = NULL;
+ }
+
+ return ret;
+}
+
+static int jz4780_rng_remove(struct platform_device *pdev)
+{
+ crypto_unregister_rng(&jz4780_rng_alg);
+
+ jz4780_rng = NULL;
+
+ return 0;
+}
+
+static const struct of_device_id jz4780_rng_dt_match[] = {
+ {
+ .compatible = "ingenic,jz4780-rng",
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, jz4780_rng_dt_match);
+
+static struct platform_driver jz4780_rng_driver = {
+ .driver = {
+ .name = "jz4780-rng",
+ .of_match_table = jz4780_rng_dt_match,
+ },
+ .probe = jz4780_rng_probe,
+ .remove = jz4780_rng_remove,
+};
+
+module_platform_driver(jz4780_rng_driver);
+
+MODULE_DESCRIPTION("Ingenic JZ4780 H/W Pseudo Random Number Generator driver");
+MODULE_AUTHOR("PrasannaKumar Muralidharan <[email protected]>");
+MODULE_LICENSE("GPL");
--
2.10.0
On Wed, Aug 23, 2017 at 08:27:04AM +0530, PrasannaKumar Muralidharan wrote:
> Add devicetree bindings for hardware pseudo random number generator
> present in Ingenic JZ4780 SoC.
>
> Signed-off-by: PrasannaKumar Muralidharan <[email protected]>
> ---
> Changes in v2:
> * Add "syscon" in CGU node's compatible section
> * Make RNG child node of CGU.
>
> .../bindings/crypto/ingenic,jz4780-rng.txt | 20 ++++++++++++++++++++
bindings/rng/ for RNG h/w.
> 1 file changed, 20 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
>
> diff --git a/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt b/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
> new file mode 100644
> index 0000000..a0c18e5
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
> @@ -0,0 +1,20 @@
> +Ingenic jz4780 RNG driver
> +
> +Required properties:
> +- compatible : Should be "ingenic,jz4780-rng"
> +
> +Example:
> +
> +cgu: jz4780-cgu@10000000 {
> + compatible = "ingenic,jz4780-cgu", "syscon";
> + reg = <0x10000000 0x100>;
> +
> + clocks = <&ext>, <&rtc>;
> + clock-names = "ext", "rtc";
> +
> + #clock-cells = <1>;
> +
> + rng: rng@d8 {
unit-address requires reg property.
> + compatible = "ingenic,jz480-rng";
> + };
> +};
> --
> 2.10.0
>
Hi Rob,
On 26 August 2017 at 03:27, Rob Herring <[email protected]> wrote:
> On Wed, Aug 23, 2017 at 08:27:04AM +0530, PrasannaKumar Muralidharan wrote:
>> Add devicetree bindings for hardware pseudo random number generator
>> present in Ingenic JZ4780 SoC.
>>
>> Signed-off-by: PrasannaKumar Muralidharan <[email protected]>
>> ---
>> Changes in v2:
>> * Add "syscon" in CGU node's compatible section
>> * Make RNG child node of CGU.
>>
>> .../bindings/crypto/ingenic,jz4780-rng.txt | 20 ++++++++++++++++++++
>
> bindings/rng/ for RNG h/w.
There are two subsystem for dealing with RNG hw. Hw_random subsystem
for true RNG (driver/char/hw_random) and crypto framework for pseudo
RNG (crypto/ and drviers/crypto). This HW is pseudo RNG so I have
placed the dt bindings in bindings/crypto as the driver itself is in
drivers/crypto folder. I am wondering if there is any relation between
driver folder and bindings folder. Can you please explain the folder
relation? Should this be put in bindings/rng or bindings/crypto?
>
>> 1 file changed, 20 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
>>
>> diff --git a/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt b/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
>> new file mode 100644
>> index 0000000..a0c18e5
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
>> @@ -0,0 +1,20 @@
>> +Ingenic jz4780 RNG driver
>> +
>> +Required properties:
>> +- compatible : Should be "ingenic,jz4780-rng"
>> +
>> +Example:
>> +
>> +cgu: jz4780-cgu@10000000 {
>> + compatible = "ingenic,jz4780-cgu", "syscon";
>> + reg = <0x10000000 0x100>;
>> +
>> + clocks = <&ext>, <&rtc>;
>> + clock-names = "ext", "rtc";
>> +
>> + #clock-cells = <1>;
>> +
>> + rng: rng@d8 {
>
> unit-address requires reg property.
The driver uses regmap to access the registers. In this case reg
property is not useful. Is reg property still needed? If not, how
should the node be declared?
>
>> + compatible = "ingenic,jz480-rng";
>> + };
>> +};
>> --
>> 2.10.0
>>
Thanks,
PrasannaKumar
On 23 August 2017 at 08:27, PrasannaKumar Muralidharan
<[email protected]> wrote:
> This patch series adds support of pseudo random number generator found
> in Ingenic's JZ4780 and X1000 SoC.
>
> Based on Paul's review comments, add 'syscon' compatible in CGU node in
> jz4780.dtsi. jz4780-rng driver uses regmap exposed via syscon interface
> to access the RNG registers. CGU driver is not modified in this patch
> set as registers used by CGU driver and this driver are different.
>
> PrasannaKumar Muralidharan (4):
> crypto: jz4780-rng: Add JZ4780 PRNG devicetree binding documentation
> crypto: jz4780-rng: Add Ingenic JZ4780 hardware PRNG driver
> crypto: jz4780-rng: Add RNG node to jz4780.dtsi
> crypto: jz4780-rng: Enable PRNG support in CI20 defconfig
>
> .../bindings/crypto/ingenic,jz4780-rng.txt | 20 +++
> MAINTAINERS | 5 +
> arch/mips/boot/dts/ingenic/jz4780.dtsi | 6 +-
> arch/mips/configs/ci20_defconfig | 5 +
> drivers/crypto/Kconfig | 19 +++
> drivers/crypto/Makefile | 1 +
> drivers/crypto/jz4780-rng.c | 168 +++++++++++++++++++++
> 7 files changed, 223 insertions(+), 1 deletion(-)
> create mode 100644 Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
> create mode 100644 drivers/crypto/jz4780-rng.c
>
> --
> 2.10.0
>
The rng node which is the child node of CGU is ignored so the driver's
probe is not called at all. Realised that the tests were using crng
instead of this. Don't know how to get this working. Will submit a new
version once the issue is fixed.
Please do not take this patch series.
Thanks,
PrasannaKumar
On Fri, Aug 25, 2017 at 10:20 PM, PrasannaKumar Muralidharan
<[email protected]> wrote:
> Hi Rob,
>
> On 26 August 2017 at 03:27, Rob Herring <[email protected]> wrote:
>> On Wed, Aug 23, 2017 at 08:27:04AM +0530, PrasannaKumar Muralidharan wrote:
>>> Add devicetree bindings for hardware pseudo random number generator
>>> present in Ingenic JZ4780 SoC.
>>>
>>> Signed-off-by: PrasannaKumar Muralidharan <[email protected]>
>>> ---
>>> Changes in v2:
>>> * Add "syscon" in CGU node's compatible section
>>> * Make RNG child node of CGU.
>>>
>>> .../bindings/crypto/ingenic,jz4780-rng.txt | 20 ++++++++++++++++++++
>>
>> bindings/rng/ for RNG h/w.
>
> There are two subsystem for dealing with RNG hw. Hw_random subsystem
> for true RNG (driver/char/hw_random) and crypto framework for pseudo
> RNG (crypto/ and drviers/crypto). This HW is pseudo RNG so I have
> placed the dt bindings in bindings/crypto as the driver itself is in
> drivers/crypto folder. I am wondering if there is any relation between
> driver folder and bindings folder. Can you please explain the folder
> relation? Should this be put in bindings/rng or bindings/crypto?
There's not a 1-1 relationship though obviously there's a lot of
overlap. I'd still say this should go in bindings/rng.
>>> 1 file changed, 20 insertions(+)
>>> create mode 100644 Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt b/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
>>> new file mode 100644
>>> index 0000000..a0c18e5
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/crypto/ingenic,jz4780-rng.txt
>>> @@ -0,0 +1,20 @@
>>> +Ingenic jz4780 RNG driver
>>> +
>>> +Required properties:
>>> +- compatible : Should be "ingenic,jz4780-rng"
>>> +
>>> +Example:
>>> +
>>> +cgu: jz4780-cgu@10000000 {
>>> + compatible = "ingenic,jz4780-cgu", "syscon";
>>> + reg = <0x10000000 0x100>;
>>> +
>>> + clocks = <&ext>, <&rtc>;
>>> + clock-names = "ext", "rtc";
>>> +
>>> + #clock-cells = <1>;
>>> +
>>> + rng: rng@d8 {
>>
>> unit-address requires reg property.
>
> The driver uses regmap to access the registers. In this case reg
> property is not useful. Is reg property still needed? If not, how
> should the node be declared?
What the driver (currently) does is irrelevant to the binding. Your
choice is either add the reg property or name the node just "rng".
Either is fine, but better to have more information than less IMO.
Rob