[PATCH v2 0/8] Add support for SafeXcel IP-76 to OMAP RNG

[PATCH v2 0/8] Add support for SafeXcel IP-76 to OMAP RNG

[Romain Perier]

The driver omap-rng has a lot of similarity with the IP block SafeXcel
IP-76. A lot of registers are the same and the way that the driver works
is very closed the description of the TRNG EIP76 in its datasheet.

This series refactorize the driver, add support for generating bigger
output random data and add a device variant for SafeXcel IP-76, found
in Armada 8K.

Romain Perier (8):
  dt-bindings: Add vendor prefix for INSIDE Secure
  dt-bindings: omap-rng: Document SafeXcel IP-76 device variant
  hwrng: omap - Switch to non-obsolete read API implementation
  hwrng: omap - Remove global definition of hwrng
  hwrng: omap - Add support for 128-bit output of data
  hwrng: omap - Don't prefix the probe message with OMAP
  hwrng: omap - Add device variant for SafeXcel IP-76 found in Armada 8K
  arm64: dts: marvell: add TRNG description for Armada 8K CP

 Documentation/devicetree/bindings/rng/omap_rng.txt |  14 +-
 .../devicetree/bindings/vendor-prefixes.txt        |   1 +
 .../boot/dts/marvell/armada-cp110-master.dtsi      |   8 ++
 .../arm64/boot/dts/marvell/armada-cp110-slave.dtsi |   8 ++
 drivers/char/hw_random/Kconfig                     |   2 +-
 drivers/char/hw_random/omap-rng.c                  | 160 +++++++++++++++------
 6 files changed, 147 insertions(+), 46 deletions(-)

-- 

Changes in v2:
 - Removed the patch introducing device resources managed API for registration

2.9.3

[PATCH v2 1/8] dt-bindings: Add vendor prefix for INSIDE Secure

[Romain Perier]

This commits adds a vendor for the company INSIDE Secure.
See https://www.insidesecure.com, for more details.

Signed-off-by: Romain Perier <romain.perier@free-electrons.com>
---
 Documentation/devicetree/bindings/vendor-prefixes.txt | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index 1992aa9..6a5e872 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -132,6 +132,7 @@ infineon Infineon Technologies
 inforce	Inforce Computing
 ingenic	Ingenic Semiconductor
 innolux	Innolux Corporation
+inside-secure	INSIDE Secure
 intel	Intel Corporation
 intercontrol	Inter Control Group
 invensense	InvenSense Inc.
-- 
2.9.3

[PATCH v2 2/8] dt-bindings: omap-rng: Document SafeXcel IP-76 device variant

[Romain Perier]

This commits add missing fields in the documentation that are used
by the new device variant. It also includes DT example to show how
the variant should be used.

Signed-off-by: Romain Perier <romain.perier@free-electrons.com>
---
 Documentation/devicetree/bindings/rng/omap_rng.txt | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/rng/omap_rng.txt b/Documentation/devicetree/bindings/rng/omap_rng.txt
index 6a62acd..4714772 100644
--- a/Documentation/devicetree/bindings/rng/omap_rng.txt
+++ b/Documentation/devicetree/bindings/rng/omap_rng.txt
@@ -1,4 +1,4 @@
-OMAP SoC HWRNG Module
+OMAP SoC and Inside-Secure HWRNG Module
 
 Required properties:
 
@@ -6,11 +6,13 @@ Required properties:
   RNG versions:
   - "ti,omap2-rng" for OMAP2.
   - "ti,omap4-rng" for OMAP4, OMAP5 and AM33XX.
+  - "inside-secure,safexcel-eip76" for SoCs with EIP76 IP block
   Note that these two versions are incompatible.
 - ti,hwmods: Name of the hwmod associated with the RNG module
 - reg : Offset and length of the register set for the module
 - interrupts : the interrupt number for the RNG module.
-		Only used for "ti,omap4-rng".
+		Used for "ti,omap4-rng" and "inside-secure,safexcel-eip76"
+- clocks: the trng clock source
 
 Example:
 /* AM335x */
@@ -20,3 +22,11 @@ rng: rng@48310000 {
 	reg = <0x48310000 0x2000>;
 	interrupts = <111>;
 };
+
+/* SafeXcel IP-76 */
+trng: rng@f2760000 {
+	compatible = "inside-secure,safexcel-eip76";
+	reg = <0xf2760000 0x7d>;
+	interrupts = <GIC_SPI 59 IRQ_TYPE_LEVEL_HIGH>;
+	clocks = <&cpm_syscon0 1 25>;
+};
-- 
2.9.3

[PATCH v2 3/8] hwrng: omap - Switch to non-obsolete read API implementation

[Romain Perier]

The ".data_present" and ".data_read" operations are marked as
OBSOLETE in the hwrng API. We have to use the ".read" operation instead.
It makes the driver simpler and removes the need to do a busy loop to
wait until enough data is generated by the IP. We simplify this step by
only checking the status of the engine, if there is data, we copy the
data to the output buffer and the amout of copied data is returned to the
caller, otherwise zero is returned. The hwrng core will re-call the read
operation as many times as required until enough data has been copied.

Signed-off-by: Romain Perier <romain.perier@free-electrons.com>
---
 drivers/char/hw_random/omap-rng.c | 39 ++++++++++++---------------------------
 1 file changed, 12 insertions(+), 27 deletions(-)

diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c
index 01d4be2..d47b24d 100644
--- a/drivers/char/hw_random/omap-rng.c
+++ b/drivers/char/hw_random/omap-rng.c
@@ -140,41 +140,27 @@ static inline void omap_rng_write(struct omap_rng_dev *priv, u16 reg,
 	__raw_writel(val, priv->base + priv->pdata->regs[reg]);
 }
 
-static int omap_rng_data_present(struct hwrng *rng, int wait)
+
+static int omap_rng_do_read(struct hwrng *rng, void *data, size_t max,
+			    bool wait)
 {
 	struct omap_rng_dev *priv;
-	int data, i;
 
 	priv = (struct omap_rng_dev *)rng->priv;
 
-	for (i = 0; i < 20; i++) {
-		data = priv->pdata->data_present(priv);
-		if (data || !wait)
-			break;
-		/* RNG produces data fast enough (2+ MBit/sec, even
-		 * during "rngtest" loads, that these delays don't
-		 * seem to trigger.  We *could* use the RNG IRQ, but
-		 * that'd be higher overhead ... so why bother?
-		 */
-		udelay(10);
-	}
-	return data;
-}
-
-static int omap_rng_data_read(struct hwrng *rng, u32 *data)
-{
-	struct omap_rng_dev *priv;
-	u32 data_size, i;
+	if (max < priv->pdata->data_size)
+		return 0;
 
-	priv = (struct omap_rng_dev *)rng->priv;
-	data_size = priv->pdata->data_size;
+	if (!priv->pdata->data_present(priv))
+		return 0;
 
-	for (i = 0; i < data_size / sizeof(u32); i++)
-		data[i] = omap_rng_read(priv, RNG_OUTPUT_L_REG + i);
+	memcpy_fromio(data, priv->base + priv->pdata->regs[RNG_OUTPUT_L_REG],
+		      priv->pdata->data_size);
 
 	if (priv->pdata->regs[RNG_INTACK_REG])
 		omap_rng_write(priv, RNG_INTACK_REG, RNG_REG_INTACK_RDY_MASK);
-	return data_size;
+
+	return priv->pdata->data_size;
 }
 
 static int omap_rng_init(struct hwrng *rng)
@@ -195,8 +181,7 @@ static void omap_rng_cleanup(struct hwrng *rng)
 
 static struct hwrng omap_rng_ops = {
 	.name		= "omap",
-	.data_present	= omap_rng_data_present,
-	.data_read	= omap_rng_data_read,
+	.read 		= omap_rng_do_read,
 	.init		= omap_rng_init,
 	.cleanup	= omap_rng_cleanup,
 };
-- 
2.9.3

[PATCH v2 4/8] hwrng: omap - Remove global definition of hwrng

[Romain Perier]

The omap-rng driver currently assumes that there will only ever be a
single instance of an RNG device. For this reason, there is a statically
allocated struct hwrng, with a fixed name. However, registering two
struct hwrng with the same isn't accepted by the RNG framework, so we
need to switch to a dynamically allocated struct hwrng, each using a
different name. Then, we define the name of this hwrng to "dev_name(dev)",
so the name of the data structure is unique per device.

Signed-off-by: Romain Perier <romain.perier@free-electrons.com>
---

Changes in v2:
 - Fix the goto label used when there is an error for devm_kstrdup

 drivers/char/hw_random/omap-rng.c | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c
index d47b24d..b20e8d7 100644
--- a/drivers/char/hw_random/omap-rng.c
+++ b/drivers/char/hw_random/omap-rng.c
@@ -127,6 +127,7 @@ struct omap_rng_dev {
 	void __iomem			*base;
 	struct device			*dev;
 	const struct omap_rng_pdata	*pdata;
+	struct hwrng rng;
 };
 
 static inline u32 omap_rng_read(struct omap_rng_dev *priv, u16 reg)
@@ -179,12 +180,6 @@ static void omap_rng_cleanup(struct hwrng *rng)
 	priv->pdata->cleanup(priv);
 }
 
-static struct hwrng omap_rng_ops = {
-	.name		= "omap",
-	.read 		= omap_rng_do_read,
-	.init		= omap_rng_init,
-	.cleanup	= omap_rng_cleanup,
-};
 
 static inline u32 omap2_rng_data_present(struct omap_rng_dev *priv)
 {
@@ -357,7 +352,11 @@ static int omap_rng_probe(struct platform_device *pdev)
 	if (!priv)
 		return -ENOMEM;
 
-	omap_rng_ops.priv = (unsigned long)priv;
+	priv->rng.read = omap_rng_do_read;
+	priv->rng.init = omap_rng_init;
+	priv->rng.cleanup = omap_rng_cleanup;
+
+	priv->rng.priv = (unsigned long)priv;
 	platform_set_drvdata(pdev, priv);
 	priv->dev = dev;
 
@@ -368,6 +367,12 @@ static int omap_rng_probe(struct platform_device *pdev)
 		goto err_ioremap;
 	}
 
+	priv->rng.name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
+	if (!priv->rng.name) {
+		ret = -ENOMEM;
+		goto err_ioremap;
+	}
+
 	pm_runtime_enable(&pdev->dev);
 	ret = pm_runtime_get_sync(&pdev->dev);
 	if (ret) {
@@ -381,7 +386,7 @@ static int omap_rng_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_ioremap;
 
-	ret = hwrng_register(&omap_rng_ops);
+	ret = hwrng_register(&priv->rng);
 	if (ret)
 		goto err_register;
 
@@ -402,7 +407,7 @@ static int omap_rng_remove(struct platform_device *pdev)
 {
 	struct omap_rng_dev *priv = platform_get_drvdata(pdev);
 
-	hwrng_unregister(&omap_rng_ops);
+	hwrng_unregister(&priv->rng);
 
 	priv->pdata->cleanup(priv);
 
-- 
2.9.3

[PATCH v2 5/8] hwrng: omap - Add support for 128-bit output of data

[Romain Perier]

So far, this driver only supports up to 64 bits of output data generated
by an RNG. Some IP blocks, like the SafeXcel IP-76 supports up to 128
bits of output data. This commits renames registers descriptions
OUTPUT_L_REG and OUTPUT_H_REG to OUTPUT_0_REG and OUPUT_1_REG,
respectively. It also adds two new values to the enumeration of existing
registers: OUTPUT_2_REG and OUTPUT_3_REG.

Signed-off-by: Romain Perier <romain.perier@free-electrons.com>
---
 drivers/char/hw_random/omap-rng.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c
index b20e8d7..6924da57 100644
--- a/drivers/char/hw_random/omap-rng.c
+++ b/drivers/char/hw_random/omap-rng.c
@@ -65,8 +65,10 @@
 #define OMAP4_RNG_OUTPUT_SIZE			0x8
 
 enum {
-	RNG_OUTPUT_L_REG = 0,
-	RNG_OUTPUT_H_REG,
+	RNG_OUTPUT_0_REG = 0,
+	RNG_OUTPUT_1_REG,
+	RNG_OUTPUT_2_REG,
+	RNG_OUTPUT_3_REG,
 	RNG_STATUS_REG,
 	RNG_INTMASK_REG,
 	RNG_INTACK_REG,
@@ -82,7 +84,7 @@ enum {
 };
 
 static const u16 reg_map_omap2[] = {
-	[RNG_OUTPUT_L_REG]	= 0x0,
+	[RNG_OUTPUT_0_REG]	= 0x0,
 	[RNG_STATUS_REG]	= 0x4,
 	[RNG_CONFIG_REG]	= 0x28,
 	[RNG_REV_REG]		= 0x3c,
@@ -90,8 +92,8 @@ static const u16 reg_map_omap2[] = {
 };
 
 static const u16 reg_map_omap4[] = {
-	[RNG_OUTPUT_L_REG]	= 0x0,
-	[RNG_OUTPUT_H_REG]	= 0x4,
+	[RNG_OUTPUT_0_REG]	= 0x0,
+	[RNG_OUTPUT_1_REG]	= 0x4,
 	[RNG_STATUS_REG]	= 0x8,
 	[RNG_INTMASK_REG]	= 0xc,
 	[RNG_INTACK_REG]	= 0x10,
@@ -155,7 +157,7 @@ static int omap_rng_do_read(struct hwrng *rng, void *data, size_t max,
 	if (!priv->pdata->data_present(priv))
 		return 0;
 
-	memcpy_fromio(data, priv->base + priv->pdata->regs[RNG_OUTPUT_L_REG],
+	memcpy_fromio(data, priv->base + priv->pdata->regs[RNG_OUTPUT_0_REG],
 		      priv->pdata->data_size);
 
 	if (priv->pdata->regs[RNG_INTACK_REG])
-- 
2.9.3

[PATCH v2 6/8] hwrng: omap - Don't prefix the probe message with OMAP

[Romain Perier]

So far, this driver was only used for OMAP SoCs. However, if a device
variant is added for an IP block that has nothing to do with the OMAP
platform, the message "OMAP Random Number Generator Ver" is displayed
anyway. Instead of hardcoding "OMAP" into this message, we decide to
only display "Random Number Generator". As dev_info is already
pre-pending the message with the name of the device, we have enough
informations.

Signed-off-by: Romain Perier <romain.perier@free-electrons.com>
---
 drivers/char/hw_random/omap-rng.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c
index 6924da57..861145e 100644
--- a/drivers/char/hw_random/omap-rng.c
+++ b/drivers/char/hw_random/omap-rng.c
@@ -392,7 +392,7 @@ static int omap_rng_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_register;
 
-	dev_info(&pdev->dev, "OMAP Random Number Generator ver. %02x\n",
+	dev_info(&pdev->dev, "Random Number Generator ver. %02x\n",
 		 omap_rng_read(priv, RNG_REV_REG));
 
 	return 0;
-- 
2.9.3

[PATCH v2 7/8] hwrng: omap - Add device variant for SafeXcel IP-76 found in Armada 8K

[Romain Perier]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset=y, Size: 6241 bytes --]

This commits adds a device variant for Safexcel,EIP76 found in Marvell
Armada 8k. It defines registers mapping with the good offset and add a
specific initialization function.

Signed-off-by: Romain Perier <romain.perier@free-electrons.com>
---

Changes in v2:
 - Call pm_runtime_put_sync from the label err_register. When there is an
   EPROBE_DEFER, strange errors can happen because the call to pm_runtime_*
   is not well balanced.

 drivers/char/hw_random/Kconfig    |  2 +-
 drivers/char/hw_random/omap-rng.c | 86 ++++++++++++++++++++++++++++++++++++++-
 2 files changed, 85 insertions(+), 3 deletions(-)

diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 56ad5a5..aea3613 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -168,7 +168,7 @@ config HW_RANDOM_IXP4XX
 
 config HW_RANDOM_OMAP
 	tristate "OMAP Random Number Generator support"
-	depends on ARCH_OMAP16XX || ARCH_OMAP2PLUS
+	depends on ARCH_OMAP16XX || ARCH_OMAP2PLUS || ARCH_MVEBU
 	default HW_RANDOM
  	---help---
  	  This driver provides kernel-side support for the Random Number
diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c
index 861145e..215c23a 100644
--- a/drivers/char/hw_random/omap-rng.c
+++ b/drivers/char/hw_random/omap-rng.c
@@ -28,6 +28,7 @@
 #include <linux/of_device.h>
 #include <linux/of_address.h>
 #include <linux/interrupt.h>
+#include <linux/clk.h>
 
 #include <asm/io.h>
 
@@ -63,6 +64,7 @@
 
 #define OMAP2_RNG_OUTPUT_SIZE			0x4
 #define OMAP4_RNG_OUTPUT_SIZE			0x8
+#define EIP76_RNG_OUTPUT_SIZE			0x10
 
 enum {
 	RNG_OUTPUT_0_REG = 0,
@@ -108,6 +110,23 @@ static const u16 reg_map_omap4[] = {
 	[RNG_SYSCONFIG_REG]	= 0x1FE4,
 };
 
+static const u16 reg_map_eip76[] = {
+	[RNG_OUTPUT_0_REG]	= 0x0,
+	[RNG_OUTPUT_1_REG]	= 0x4,
+	[RNG_OUTPUT_2_REG]	= 0x8,
+	[RNG_OUTPUT_3_REG]	= 0xc,
+	[RNG_STATUS_REG]	= 0x10,
+	[RNG_INTACK_REG]	= 0x10,
+	[RNG_CONTROL_REG]	= 0x14,
+	[RNG_CONFIG_REG]	= 0x18,
+	[RNG_ALARMCNT_REG]	= 0x1c,
+	[RNG_FROENABLE_REG]	= 0x20,
+	[RNG_FRODETUNE_REG]	= 0x24,
+	[RNG_ALARMMASK_REG]	= 0x28,
+	[RNG_ALARMSTOP_REG]	= 0x2c,
+	[RNG_REV_REG]		= 0x7c,
+};
+
 struct omap_rng_dev;
 /**
  * struct omap_rng_pdata - RNG IP block-specific data
@@ -130,6 +149,7 @@ struct omap_rng_dev {
 	struct device			*dev;
 	const struct omap_rng_pdata	*pdata;
 	struct hwrng rng;
+	struct clk 			*clk;
 };
 
 static inline u32 omap_rng_read(struct omap_rng_dev *priv, u16 reg)
@@ -213,6 +233,38 @@ static inline u32 omap4_rng_data_present(struct omap_rng_dev *priv)
 	return omap_rng_read(priv, RNG_STATUS_REG) & RNG_REG_STATUS_RDY;
 }
 
+static int eip76_rng_init(struct omap_rng_dev *priv)
+{
+	u32 val;
+
+	/* Return if RNG is already running. */
+	if (omap_rng_read(priv, RNG_CONTROL_REG) & RNG_CONTROL_ENABLE_TRNG_MASK)
+		return 0;
+
+	/*  Number of 512 bit blocks of raw Noise Source output data that must
+	 *  be processed by either the Conditioning Function or the
+	 *  SP 800-90 DRBG ‘BC_DF’ functionality to yield a ‘full entropy’
+	 *  output value.
+	 */
+	val = 0x5 << RNG_CONFIG_MIN_REFIL_CYCLES_SHIFT;
+
+	/* Number of FRO samples that are XOR-ed together into one bit to be
+	 * shifted into the main shift register
+	 */
+	val |= RNG_CONFIG_MAX_REFIL_CYCLES << RNG_CONFIG_MAX_REFIL_CYCLES_SHIFT;
+	omap_rng_write(priv, RNG_CONFIG_REG, val);
+
+	/* Enable all available FROs */
+	omap_rng_write(priv, RNG_FRODETUNE_REG, 0x0);
+	omap_rng_write(priv, RNG_FROENABLE_REG, RNG_REG_FROENABLE_MASK);
+
+	/* Enable TRNG */
+	val = RNG_CONTROL_ENABLE_TRNG_MASK;
+	omap_rng_write(priv, RNG_CONTROL_REG, val);
+
+	return 0;
+}
+
 static int omap4_rng_init(struct omap_rng_dev *priv)
 {
 	u32 val;
@@ -282,6 +334,14 @@ static struct omap_rng_pdata omap4_rng_pdata = {
 	.cleanup	= omap4_rng_cleanup,
 };
 
+static struct omap_rng_pdata eip76_rng_pdata = {
+	.regs		= (u16 *)reg_map_eip76,
+	.data_size	= EIP76_RNG_OUTPUT_SIZE,
+	.data_present	= omap4_rng_data_present,
+	.init		= eip76_rng_init,
+	.cleanup	= omap4_rng_cleanup,
+};
+
 static const struct of_device_id omap_rng_of_match[] = {
 		{
 			.compatible	= "ti,omap2-rng",
@@ -291,6 +351,10 @@ static const struct of_device_id omap_rng_of_match[] = {
 			.compatible	= "ti,omap4-rng",
 			.data		= &omap4_rng_pdata,
 		},
+		{
+			.compatible	= "inside-secure,safexcel-eip76",
+			.data		= &eip76_rng_pdata,
+		},
 		{},
 };
 MODULE_DEVICE_TABLE(of, omap_rng_of_match);
@@ -309,7 +373,8 @@ static int of_get_omap_rng_device_details(struct omap_rng_dev *priv,
 	}
 	priv->pdata = match->data;
 
-	if (of_device_is_compatible(dev->of_node, "ti,omap4-rng")) {
+	if (of_device_is_compatible(dev->of_node, "ti,omap4-rng") ||
+	    of_device_is_compatible(dev->of_node, "inside-secure,safexcel-eip76")) {
 		irq = platform_get_irq(pdev, 0);
 		if (irq < 0) {
 			dev_err(dev, "%s: error getting IRQ resource - %d\n",
@@ -325,6 +390,16 @@ static int of_get_omap_rng_device_details(struct omap_rng_dev *priv,
 			return err;
 		}
 		omap_rng_write(priv, RNG_INTMASK_REG, RNG_SHUTDOWN_OFLO_MASK);
+
+		priv->clk = of_clk_get(pdev->dev.of_node, 0);
+		if (IS_ERR(priv->clk) && PTR_ERR(priv->clk) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+		if (!IS_ERR(priv->clk)) {
+			err = clk_prepare_enable(priv->clk);
+			if (err)
+				dev_err(&pdev->dev, "unable to enable the clk, "
+						    "err = %d\n", err);
+		}
 	}
 	return 0;
 }
@@ -386,7 +461,7 @@ static int omap_rng_probe(struct platform_device *pdev)
 	ret = (dev->of_node) ? of_get_omap_rng_device_details(priv, pdev) :
 				get_omap_rng_device_details(priv);
 	if (ret)
-		goto err_ioremap;
+		goto err_register;
 
 	ret = hwrng_register(&priv->rng);
 	if (ret)
@@ -399,7 +474,11 @@ static int omap_rng_probe(struct platform_device *pdev)
 
 err_register:
 	priv->base = NULL;
+	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
+
+	if (!IS_ERR(priv->clk))
+		clk_disable_unprepare(priv->clk);
 err_ioremap:
 	dev_err(dev, "initialization failed.\n");
 	return ret;
@@ -416,6 +495,9 @@ static int omap_rng_remove(struct platform_device *pdev)
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
+	if (!IS_ERR(priv->clk))
+		clk_disable_unprepare(priv->clk);
+
 	return 0;
 }
 
-- 
2.9.3

[PATCH v2 8/8] arm64: dts: marvell: add TRNG description for Armada 8K CP

[Romain Perier]

This commits adds the devicetree description of the SafeXcel IP-76 TRNG
found in the two Armada CP110.

Signed-off-by: Romain Perier <romain.perier@free-electrons.com>
---
 arch/arm64/boot/dts/marvell/armada-cp110-master.dtsi | 8 ++++++++
 arch/arm64/boot/dts/marvell/armada-cp110-slave.dtsi  | 8 ++++++++
 2 files changed, 16 insertions(+)

diff --git a/arch/arm64/boot/dts/marvell/armada-cp110-master.dtsi b/arch/arm64/boot/dts/marvell/armada-cp110-master.dtsi
index da31bbb..aaffa24 100644
--- a/arch/arm64/boot/dts/marvell/armada-cp110-master.dtsi
+++ b/arch/arm64/boot/dts/marvell/armada-cp110-master.dtsi
@@ -164,6 +164,14 @@
 				clocks = <&cpm_syscon0 1 21>;
 				status = "disabled";
 			};
+
+			cpm_trng: trng@760000 {
+				compatible = "marvell,armada-8k-rng", "inside-secure,safexcel-eip76";
+				reg = <0x760000 0x7d>;
+				interrupts = <GIC_SPI 59 IRQ_TYPE_LEVEL_HIGH>;
+				clocks = <&cpm_syscon0 1 25>;
+				status = "okay";
+			};
 		};
 
 		cpm_pcie0: pcie@f2600000 {
diff --git a/arch/arm64/boot/dts/marvell/armada-cp110-slave.dtsi b/arch/arm64/boot/dts/marvell/armada-cp110-slave.dtsi
index 6ff1201..216de12 100644
--- a/arch/arm64/boot/dts/marvell/armada-cp110-slave.dtsi
+++ b/arch/arm64/boot/dts/marvell/armada-cp110-slave.dtsi
@@ -164,6 +164,14 @@
 				clocks = <&cps_syscon0 1 21>;
 				status = "disabled";
 			};
+
+			cps_trng: trng@760000 {
+				compatible = "marvell,armada-8k-rng", "inside-secure,safexcel-eip76";
+				reg = <0x760000 0x7d>;
+				interrupts = <GIC_SPI 312 IRQ_TYPE_LEVEL_HIGH>;
+				clocks = <&cps_syscon0 1 25>;
+				status = "okay";
+			};
 		};
 
 		cps_pcie0: pcie@f4600000 {
-- 
2.9.3

Re: [PATCH v2 3/8] hwrng: omap - Switch to non-obsolete read API implementation

[Herbert Xu]

On Wed, Sep 07, 2016 at 05:57:38PM +0200, Romain Perier wrote:
> +
> +static int omap_rng_do_read(struct hwrng *rng, void *data, size_t max,
> +			    bool wait)
>  {
>  	struct omap_rng_dev *priv;
> -	int data, i;
>  
>  	priv = (struct omap_rng_dev *)rng->priv;
>  
> -	for (i = 0; i < 20; i++) {
> -		data = priv->pdata->data_present(priv);
> -		if (data || !wait)
> -			break;
> -		/* RNG produces data fast enough (2+ MBit/sec, even
> -		 * during "rngtest" loads, that these delays don't
> -		 * seem to trigger.  We *could* use the RNG IRQ, but
> -		 * that'd be higher overhead ... so why bother?
> -		 */
> -		udelay(10);

So in the wait case you're changing the driver's behaviour.  Instead
of waiting for 1us you'll now wait for 1s if there is no data.  Is
this what really what you want?

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 v2 3/8] hwrng: omap - Switch to non-obsolete read API implementation

[Romain Perier]

Hi,

Le 13/09/2016 11:48, Herbert Xu a écrit :
> On Wed, Sep 07, 2016 at 05:57:38PM +0200, Romain Perier wrote:
>> +
>> +static int omap_rng_do_read(struct hwrng *rng, void *data, size_t max,
>> +			    bool wait)
>>   {
>>   	struct omap_rng_dev *priv;
>> -	int data, i;
>>
>>   	priv = (struct omap_rng_dev *)rng->priv;
>>
>> -	for (i = 0; i < 20; i++) {
>> -		data = priv->pdata->data_present(priv);
>> -		if (data || !wait)
>> -			break;
>> -		/* RNG produces data fast enough (2+ MBit/sec, even
>> -		 * during "rngtest" loads, that these delays don't
>> -		 * seem to trigger.  We *could* use the RNG IRQ, but
>> -		 * that'd be higher overhead ... so why bother?
>> -		 */
>> -		udelay(10);
>
> So in the wait case you're changing the driver's behaviour.  Instead
> of waiting for 1us you'll now wait for 1s if there is no data.  Is
> this what really what you want?
>
> Cheers,
>

Mhhh, you're right, in this specific case it will add more latency... 
with busy loop, on average, 20 retries will be enough to have data...

Thanks!
-- 
Romain Perier, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com