Some devices may need to perform a reset before using the RNG, such as the
BCM6368.
v6: fix dt-bindings documentation, add patch makings clocks mandatory for
BCM6368.
v5: remove reset_control_rearm() and apply on latest herbert/cryptodev-2.6.git.
v4: fix documentation, add reset_control_rearm().
v3: make resets required if brcm,bcm6368-rng.
v2: document reset support.
Álvaro Fernández Rojas (3):
dt-bindings: rng: bcm2835: add clock constraints
dt-bindings: rng: bcm2835: document reset support
hwrng: bcm2835: add reset support
.../devicetree/bindings/rng/brcm,bcm2835.yaml | 21 +++++++++++++++++++
drivers/char/hw_random/bcm2835-rng.c | 10 +++++++++
2 files changed, 31 insertions(+)
--
2.20.1
BCM6368 devices need to reset the IPSEC controller in order to generate true
random numbers.
This is what BCM6368 produces without a reset:
root@OpenWrt:/# cat /dev/hwrng | rngtest -c 1000
rngtest 6.10
Copyright (c) 2004 by Henrique de Moraes Holschuh
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
rngtest: starting FIPS tests...
rngtest: bits received from input: 20000032
rngtest: FIPS 140-2 successes: 0
rngtest: FIPS 140-2 failures: 1000
rngtest: FIPS 140-2(2001-10-10) Monobit: 2
rngtest: FIPS 140-2(2001-10-10) Poker: 1000
rngtest: FIPS 140-2(2001-10-10) Runs: 1000
rngtest: FIPS 140-2(2001-10-10) Long run: 30
rngtest: FIPS 140-2(2001-10-10) Continuous run: 0
rngtest: input channel speed: (min=37.253; avg=320.827; max=635.783)Mibits/s
rngtest: FIPS tests speed: (min=12.141; avg=15.034; max=16.428)Mibits/s
rngtest: Program run time: 1336176 microseconds
Signed-off-by: Álvaro Fernández Rojas <[email protected]>
---
v6: fix commit description.
v5: remove reset_control_rearm().
v4: add reset_control_rearm().
v3: no changes.
v2: no changes.
drivers/char/hw_random/bcm2835-rng.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c
index be5be395b341..e7dd457e9b22 100644
--- a/drivers/char/hw_random/bcm2835-rng.c
+++ b/drivers/char/hw_random/bcm2835-rng.c
@@ -13,6 +13,7 @@
#include <linux/platform_device.h>
#include <linux/printk.h>
#include <linux/clk.h>
+#include <linux/reset.h>
#define RNG_CTRL 0x0
#define RNG_STATUS 0x4
@@ -32,6 +33,7 @@ struct bcm2835_rng_priv {
void __iomem *base;
bool mask_interrupts;
struct clk *clk;
+ struct reset_control *reset;
};
static inline struct bcm2835_rng_priv *to_rng_priv(struct hwrng *rng)
@@ -92,6 +94,10 @@ static int bcm2835_rng_init(struct hwrng *rng)
if (ret)
return ret;
+ ret = reset_control_reset(priv->reset);
+ if (ret)
+ return ret;
+
if (priv->mask_interrupts) {
/* mask the interrupt */
val = rng_readl(priv, RNG_INT_MASK);
@@ -156,6 +162,10 @@ static int bcm2835_rng_probe(struct platform_device *pdev)
if (IS_ERR(priv->clk))
return PTR_ERR(priv->clk);
+ priv->reset = devm_reset_control_get_optional_exclusive(dev, NULL);
+ if (IS_ERR(priv->reset))
+ return PTR_ERR(priv->reset);
+
priv->rng.name = pdev->name;
priv->rng.init = bcm2835_rng_init;
priv->rng.read = bcm2835_rng_read;
--
2.20.1
brcm,bcm6368-rng controllers require resetting the IPSEC clock in order to get
a functional RNG.
Signed-off-by: Álvaro Fernández Rojas <[email protected]>
---
v6: fix dt-bindings warnings.
v5: no changes.
v4: pass dt_binding_check.
v3: make resets required if brcm,bcm6368-rng.
v2: document reset support.
.../devicetree/bindings/rng/brcm,bcm2835.yaml | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/Documentation/devicetree/bindings/rng/brcm,bcm2835.yaml b/Documentation/devicetree/bindings/rng/brcm,bcm2835.yaml
index 5174492e22f3..6da674666d45 100644
--- a/Documentation/devicetree/bindings/rng/brcm,bcm2835.yaml
+++ b/Documentation/devicetree/bindings/rng/brcm,bcm2835.yaml
@@ -28,6 +28,12 @@ properties:
clock-names:
const: ipsec
+ resets:
+ maxItems: 1
+
+ reset-names:
+ const: ipsec
+
interrupts:
maxItems: 1
@@ -44,6 +50,8 @@ then:
required:
- clocks
- clock-names
+ - resets
+ - reset-names
additionalProperties: false
@@ -68,4 +76,7 @@ examples:
clocks = <&periph_clk 18>;
clock-names = "ipsec";
+
+ resets = <&periph_rst 4>;
+ reset-names = "ipsec";
};
--
2.20.1
On Fri, 2021-03-05 at 08:01 +0100, Álvaro Fernández Rojas wrote:
> BCM6368 devices need to reset the IPSEC controller in order to generate true
> random numbers.
>
> This is what BCM6368 produces without a reset:
> root@OpenWrt:/# cat /dev/hwrng | rngtest -c 1000
> rngtest 6.10
> Copyright (c) 2004 by Henrique de Moraes Holschuh
> This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
>
> rngtest: starting FIPS tests...
> rngtest: bits received from input: 20000032
> rngtest: FIPS 140-2 successes: 0
> rngtest: FIPS 140-2 failures: 1000
> rngtest: FIPS 140-2(2001-10-10) Monobit: 2
> rngtest: FIPS 140-2(2001-10-10) Poker: 1000
> rngtest: FIPS 140-2(2001-10-10) Runs: 1000
> rngtest: FIPS 140-2(2001-10-10) Long run: 30
> rngtest: FIPS 140-2(2001-10-10) Continuous run: 0
> rngtest: input channel speed: (min=37.253; avg=320.827; max=635.783)Mibits/s
> rngtest: FIPS tests speed: (min=12.141; avg=15.034; max=16.428)Mibits/s
> rngtest: Program run time: 1336176 microseconds
>
> Signed-off-by: Álvaro Fernández Rojas <[email protected]>
Reviewed-by: Philipp Zabel <[email protected]>
regards
Philipp
> ---
> v6: fix commit description.
> v5: remove reset_control_rearm().
> v4: add reset_control_rearm().
> v3: no changes.
> v2: no changes.
>
> drivers/char/hw_random/bcm2835-rng.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c
> index be5be395b341..e7dd457e9b22 100644
> --- a/drivers/char/hw_random/bcm2835-rng.c
> +++ b/drivers/char/hw_random/bcm2835-rng.c
> @@ -13,6 +13,7 @@
> #include <linux/platform_device.h>
> #include <linux/printk.h>
> #include <linux/clk.h>
> +#include <linux/reset.h>
>
> #define RNG_CTRL 0x0
> #define RNG_STATUS 0x4
> @@ -32,6 +33,7 @@ struct bcm2835_rng_priv {
> void __iomem *base;
> bool mask_interrupts;
> struct clk *clk;
> + struct reset_control *reset;
> };
>
> static inline struct bcm2835_rng_priv *to_rng_priv(struct hwrng *rng)
> @@ -92,6 +94,10 @@ static int bcm2835_rng_init(struct hwrng *rng)
> if (ret)
> return ret;
>
> + ret = reset_control_reset(priv->reset);
> + if (ret)
> + return ret;
> +
> if (priv->mask_interrupts) {
> /* mask the interrupt */
> val = rng_readl(priv, RNG_INT_MASK);
> @@ -156,6 +162,10 @@ static int bcm2835_rng_probe(struct platform_device *pdev)
> if (IS_ERR(priv->clk))
> return PTR_ERR(priv->clk);
>
> + priv->reset = devm_reset_control_get_optional_exclusive(dev, NULL);
> + if (IS_ERR(priv->reset))
> + return PTR_ERR(priv->reset);
> +
> priv->rng.name = pdev->name;
> priv->rng.init = bcm2835_rng_init;
> priv->rng.read = bcm2835_rng_read;
On 3/4/21 11:01 PM, Álvaro Fernández Rojas wrote:
> brcm,bcm6368-rng controllers require resetting the IPSEC clock in order to get
> a functional RNG.
>
> Signed-off-by: Álvaro Fernández Rojas <[email protected]>
Acked-by: Florian Fainelli <[email protected]>
--
Florian
On Fri, Mar 05, 2021 at 08:01:29AM +0100, ?lvaro Fern?ndez Rojas wrote:
> Some devices may need to perform a reset before using the RNG, such as the
> BCM6368.
>
> v6: fix dt-bindings documentation, add patch makings clocks mandatory for
> BCM6368.
> v5: remove reset_control_rearm() and apply on latest herbert/cryptodev-2.6.git.
> v4: fix documentation, add reset_control_rearm().
> v3: make resets required if brcm,bcm6368-rng.
> v2: document reset support.
>
> ?lvaro Fern?ndez Rojas (3):
> dt-bindings: rng: bcm2835: add clock constraints
> dt-bindings: rng: bcm2835: document reset support
> hwrng: bcm2835: add reset support
>
> .../devicetree/bindings/rng/brcm,bcm2835.yaml | 21 +++++++++++++++++++
> drivers/char/hw_random/bcm2835-rng.c | 10 +++++++++
> 2 files changed, 31 insertions(+)
All applied. Thanks.
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt