Subject: [PATCH v3 0/4] crypto: Add driver for JZ4780 PRNG

This patch series adds support of pseudo random number generator found
in Ingenic's JZ4780 and X1000 SoC.

Create cgublock node which has CGU and RNG node as its children. The
cgublock node uses "simple-bus" compatible which helps in exposing CGU
and RNG nodes without changing CGU driver. Add 'syscon' compatible in
CGU node in jz4780.dtsi. The 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

.../devicetree/bindings/rng/ingenic,jz4780-rng.txt | 21 +++
MAINTAINERS | 7 +
arch/mips/boot/dts/ingenic/jz4780.dtsi | 25 ++-
arch/mips/configs/ci20_defconfig | 5 +
drivers/crypto/Kconfig | 19 ++
drivers/crypto/Makefile | 1 +
drivers/crypto/jz4780-rng.c | 193 +++++++++++++++++++++
7 files changed, 266 insertions(+), 5 deletions(-)
create mode 100644 Documentation/devicetree/bindings/rng/ingenic,jz4780-rng.txt
create mode 100644 drivers/crypto/jz4780-rng.c

--
2.10.0


Subject: [PATCH v3 1/4] crypto: jz4780-rng: Add JZ4780 PRNG devicetree binding documentation

Add devicetree bindings for hardware pseudo random number generator
present in Ingenic JZ4780 SoC.

Signed-off-by: PrasannaKumar Muralidharan <[email protected]>
---
Changes in v3:
* Create a cgublock node with "simple-bus" compatible
* Make CGU and RNG node as children of cgublock node.

Changes in v2:
* Add "syscon" in CGU node's compatible section
* Make RNG child node of CGU.

.../devicetree/bindings/rng/ingenic,jz4780-rng.txt | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
create mode 100644 Documentation/devicetree/bindings/rng/ingenic,jz4780-rng.txt

diff --git a/Documentation/devicetree/bindings/rng/ingenic,jz4780-rng.txt b/Documentation/devicetree/bindings/rng/ingenic,jz4780-rng.txt
new file mode 100644
index 0000000..765df9c
--- /dev/null
+++ b/Documentation/devicetree/bindings/rng/ingenic,jz4780-rng.txt
@@ -0,0 +1,21 @@
+Ingenic jz4780 RNG driver
+
+Required properties:
+- compatible : Should be "ingenic,jz4780-rng"
+
+Example:
+
+cgublock {
+ compatible = "simple-bus";
+
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ reg = <0x10000000 0x100>;
+ ranges;
+
+ rng: rng@d8 {
+ compatible = "ingenic,jz4780-rng";
+ reg = <0x100000d8 0x8>;
+ };
+};
--
2.10.0

Subject: [PATCH v3 2/4] crypto: jz4780-rng: Add Ingenic JZ4780 hardware PRNG driver

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 v3:
* Add seeding support
* Reduce delay

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 | 7 ++
drivers/crypto/Kconfig | 19 +++++
drivers/crypto/Makefile | 1 +
drivers/crypto/jz4780-rng.c | 193 ++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 220 insertions(+)
create mode 100644 drivers/crypto/jz4780-rng.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 2093060..d2341a7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6783,6 +6783,13 @@ L: [email protected]
S: Maintained
F: drivers/mtd/nand/jz4780_*

+INGENIC JZ4780 PRNG DRIVER
+M: PrasannaKumar Muralidharan <[email protected]>
+L: [email protected]
+S: Maintained
+F: drivers/crypto/jz4780-rng.c
+F: Documentation/devicetree/bindings/rng/ingenic,jz4780-rng.txt
+
INOTIFY
M: Jan Kara <[email protected]>
R: Amir Goldstein <[email protected]>
diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index fe33c19..f3ac1cd 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -613,6 +613,25 @@ 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 808432b..a09d9f4 100644
--- a/drivers/crypto/Makefile
+++ b/drivers/crypto/Makefile
@@ -14,6 +14,7 @@ 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..918ba94
--- /dev/null
+++ b/drivers/crypto/jz4780-rng.c
@@ -0,0 +1,193 @@
+/*
+ * 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;
+ u32 seed;
+};
+
+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_seed(struct crypto_rng *tfm, const u8 *seed,
+ unsigned int slen)
+{
+ struct jz4780_rng_ctx *ctx = crypto_rng_ctx(tfm);
+ struct jz4780_rng *rng = ctx->rng;
+
+ memcpy((void *)&rng->seed, seed, slen);
+
+ return 0;
+}
+
+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);
+
+ /* Write seed */
+ jz4780_rng_writel(rng, rng->seed, REG_RNG_DATA);
+
+ while (dlen >= 4) {
+ udelay(2);
+ data = jz4780_rng_readl(rng, REG_RNG_DATA);
+ memcpy((void *)dst, (void *)&data, 4);
+ dlen -= 4;
+ dst += 4;
+ };
+
+ if (dlen > 0) {
+ udelay(2);
+ data = jz4780_rng_readl(rng, REG_RNG_DATA);
+ memcpy((void *)dst, (void *)&data, dlen);
+ }
+
+ udelay(2);
+ /* Update the seed */
+ data = jz4780_rng_readl(rng, REG_RNG_DATA);
+ rng->seed = data;
+
+ 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,
+ .seed = jz4780_rng_seed,
+ .seedsize = 4,
+ .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

Subject: [PATCH v3 3/4] crypto: jz4780-rng: Add RNG node to jz4780.dtsi

Add RNG node to jz4780 dtsi. This driver uses registers that are part of
the register set used by Ingenic CGU driver. Use regmap in RNG driver to
access its register. Create 'simple-bus' node, make CGU and RNG node as
child of it so that both the nodes are visible without changing CGU
driver code.

Signed-off-by: PrasannaKumar Muralidharan <[email protected]>
---
Changes in v3:
* Create a cgublock node with "simple-bus" compatible
* Make CGU and RNG node as children of cgublock node.

Changes in v2:
* Add "syscon" in CGU node's compatible section
* Make RNG child node of CGU.

arch/mips/boot/dts/ingenic/jz4780.dtsi | 25 ++++++++++++++++++++-----
1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/arch/mips/boot/dts/ingenic/jz4780.dtsi b/arch/mips/boot/dts/ingenic/jz4780.dtsi
index 4853ef6..5953b97 100644
--- a/arch/mips/boot/dts/ingenic/jz4780.dtsi
+++ b/arch/mips/boot/dts/ingenic/jz4780.dtsi
@@ -34,14 +34,29 @@
clock-frequency = <32768>;
};

- cgu: jz4780-cgu@10000000 {
- compatible = "ingenic,jz4780-cgu";
+ cgublock {
+ compatible = "simple-bus";
+
+ #address-cells = <1>;
+ #size-cells = <1>;
+
reg = <0x10000000 0x100>;
+ ranges;

- clocks = <&ext>, <&rtc>;
- clock-names = "ext", "rtc";
+ cgu: jz4780-cgu@0 {
+ compatible = "ingenic,jz4780-cgu";
+ reg = <0x10000000 0x100>;

- #clock-cells = <1>;
+ clocks = <&ext>, <&rtc>;
+ clock-names = "ext", "rtc";
+
+ #clock-cells = <1>;
+ };
+
+ rng: rng@d8 {
+ compatible = "ingenic,jz4780-rng";
+ reg = <0x100000d8 0x8>;
+ };
};

pinctrl: pin-controller@10010000 {
--
2.10.0

Subject: [PATCH v3 4/4] crypto: jz4780-rng: Enable PRNG support in CI20 defconfig

Enable PRNG driver support in MIPS Creator CI20 default config.

Signed-off-by: PrasannaKumar Muralidharan <[email protected]>
---
No changes in v3

No changes in v2

arch/mips/configs/ci20_defconfig | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/mips/configs/ci20_defconfig b/arch/mips/configs/ci20_defconfig
index b42cfa7..9f48f2c 100644
--- a/arch/mips/configs/ci20_defconfig
+++ b/arch/mips/configs/ci20_defconfig
@@ -88,6 +88,11 @@ CONFIG_SERIAL_8250_RUNTIME_UARTS=5
CONFIG_SERIAL_8250_INGENIC=y
CONFIG_SERIAL_OF_PLATFORM=y
# CONFIG_HW_RANDOM is not set
+CONFIG_CRYPTO_USER=y
+CONFIG_CRYPTO_USER_API=y
+CONFIG_CRYPTO_USER_API_RNG=y
+CONFIG_CRYPTO_HW=y
+CONFIG_CRYPTO_DEV_JZ4780_RNG=y
CONFIG_I2C=y
CONFIG_I2C_JZ4780=y
CONFIG_GPIO_SYSFS=y
--
2.10.0

2017-10-12 14:30:41

by Herbert Xu

[permalink] [raw]
Subject: Re: [PATCH v3 0/4] crypto: Add driver for JZ4780 PRNG

On Mon, Sep 18, 2017 at 07:32:37PM +0530, PrasannaKumar Muralidharan wrote:
> This patch series adds support of pseudo random number generator found
> in Ingenic's JZ4780 and X1000 SoC.
>
> Create cgublock node which has CGU and RNG node as its children. The
> cgublock node uses "simple-bus" compatible which helps in exposing CGU
> and RNG nodes without changing CGU driver. Add 'syscon' compatible in
> CGU node in jz4780.dtsi. The 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

Please indicate which patches are intended to go through the crypto
trees.

Thanks,
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

Subject: Re: [PATCH v3 0/4] crypto: Add driver for JZ4780 PRNG

Hi Herbert,

On 12 October 2017 at 20:00, Herbert Xu <[email protected]> wrote:
> On Mon, Sep 18, 2017 at 07:32:37PM +0530, PrasannaKumar Muralidharan wrote:
>> This patch series adds support of pseudo random number generator found
>> in Ingenic's JZ4780 and X1000 SoC.
>>
>> Create cgublock node which has CGU and RNG node as its children. The
>> cgublock node uses "simple-bus" compatible which helps in exposing CGU
>> and RNG nodes without changing CGU driver. Add 'syscon' compatible in
>> CGU node in jz4780.dtsi. The 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
>
> Please indicate which patches are intended to go through the crypto
> trees.

>From https://patchwork.linux-mips.org/patch/17162/ I expect the same.
Either all patches go via crypto tree or via mips tree.
The dtsi changes is not yet acked by MIPS / JZ4780 maintainer. Let's
wait for it.

Thanks,
PrasannaKumar

Subject: Re: [PATCH v3 0/4] crypto: Add driver for JZ4780 PRNG

Hi Ralf,

On 12 October 2017 at 22:59, PrasannaKumar Muralidharan
<[email protected]> wrote:
> Hi Herbert,
>
> On 12 October 2017 at 20:00, Herbert Xu <[email protected]> wrote:
>> On Mon, Sep 18, 2017 at 07:32:37PM +0530, PrasannaKumar Muralidharan wrote:
>>> This patch series adds support of pseudo random number generator found
>>> in Ingenic's JZ4780 and X1000 SoC.
>>>
>>> Create cgublock node which has CGU and RNG node as its children. The
>>> cgublock node uses "simple-bus" compatible which helps in exposing CGU
>>> and RNG nodes without changing CGU driver. Add 'syscon' compatible in
>>> CGU node in jz4780.dtsi. The 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
>>
>> Please indicate which patches are intended to go through the crypto
>> trees.
>
> From https://patchwork.linux-mips.org/patch/17162/ I expect the same.
> Either all patches go via crypto tree or via mips tree.
> The dtsi changes is not yet acked by MIPS / JZ4780 maintainer. Let's
> wait for it.
>
> Thanks,
> PrasannaKumar

Should I do anything more for this series?

Thanks,
PrasannaKumar