From: Matthias Brugger <[email protected]>
When trying to disable the block we bitwise or the control
register with value zero. This will leave the block always turned on.
Fix this by setting the corresponding bit to zero.
Fixes: c83d45d5685f ("hwrng: iproc-rng200 - Add Broadcom IPROC RNG driver")
Signed-off-by: Matthias Brugger <[email protected]>
---
drivers/char/hw_random/iproc-rng200.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/char/hw_random/iproc-rng200.c b/drivers/char/hw_random/iproc-rng200.c
index 01583faf9893..e106ce3c0146 100644
--- a/drivers/char/hw_random/iproc-rng200.c
+++ b/drivers/char/hw_random/iproc-rng200.c
@@ -28,7 +28,6 @@
#define RNG_CTRL_OFFSET 0x00
#define RNG_CTRL_RNG_RBGEN_MASK 0x00001FFF
#define RNG_CTRL_RNG_RBGEN_ENABLE 0x00000001
-#define RNG_CTRL_RNG_RBGEN_DISABLE 0x00000000
#define RNG_SOFT_RESET_OFFSET 0x04
#define RNG_SOFT_RESET 0x00000001
@@ -61,7 +60,7 @@ static void iproc_rng200_restart(void __iomem *rng_base)
/* Disable RBG */
val = ioread32(rng_base + RNG_CTRL_OFFSET);
val &= ~RNG_CTRL_RNG_RBGEN_MASK;
- val |= RNG_CTRL_RNG_RBGEN_DISABLE;
+ val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
iowrite32(val, rng_base + RNG_CTRL_OFFSET);
/* Clear all interrupt status */
@@ -174,7 +173,7 @@ static void iproc_rng200_cleanup(struct hwrng *rng)
/* Disable RNG hardware */
val = ioread32(priv->base + RNG_CTRL_OFFSET);
val &= ~RNG_CTRL_RNG_RBGEN_MASK;
- val |= RNG_CTRL_RNG_RBGEN_DISABLE;
+ val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
iowrite32(val, priv->base + RNG_CTRL_OFFSET);
}
--
2.29.2
On 2020-12-14 8:04 a.m., [email protected] wrote:
> From: Matthias Brugger <[email protected]>
>
> When trying to disable the block we bitwise or the control
> register with value zero. This will leave the block always turned on.
> Fix this by setting the corresponding bit to zero.
>
> Fixes: c83d45d5685f ("hwrng: iproc-rng200 - Add Broadcom IPROC RNG driver")
Commit message needs to be re-written.
I don't think this is an actual fix as the ~RNG_CTL_RNG_RBGEN_MASK already zeros the bit. This is just a code change, which is fine because it makes things clearer
> Signed-off-by: Matthias Brugger <[email protected]>
> ---
>
> drivers/char/hw_random/iproc-rng200.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/char/hw_random/iproc-rng200.c b/drivers/char/hw_random/iproc-rng200.c
> index 01583faf9893..e106ce3c0146 100644
> --- a/drivers/char/hw_random/iproc-rng200.c
> +++ b/drivers/char/hw_random/iproc-rng200.c
> @@ -28,7 +28,6 @@
> #define RNG_CTRL_OFFSET 0x00
> #define RNG_CTRL_RNG_RBGEN_MASK 0x00001FFF
> #define RNG_CTRL_RNG_RBGEN_ENABLE 0x00000001
> -#define RNG_CTRL_RNG_RBGEN_DISABLE 0x00000000
>
> #define RNG_SOFT_RESET_OFFSET 0x04
> #define RNG_SOFT_RESET 0x00000001
> @@ -61,7 +60,7 @@ static void iproc_rng200_restart(void __iomem *rng_base)
> /* Disable RBG */
> val = ioread32(rng_base + RNG_CTRL_OFFSET);
> val &= ~RNG_CTRL_RNG_RBGEN_MASK;
This mask will already zero the enable bit.
> - val |= RNG_CTRL_RNG_RBGEN_DISABLE;
> + val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
> iowrite32(val, rng_base + RNG_CTRL_OFFSET);
>
> /* Clear all interrupt status */
> @@ -174,7 +173,7 @@ static void iproc_rng200_cleanup(struct hwrng *rng)
> /* Disable RNG hardware */
> val = ioread32(priv->base + RNG_CTRL_OFFSET);
> val &= ~RNG_CTRL_RNG_RBGEN_MASK;
> - val |= RNG_CTRL_RNG_RBGEN_DISABLE;
> + val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
> iowrite32(val, priv->base + RNG_CTRL_OFFSET);
> }
>
On 12/14/20 8:04 AM, [email protected] wrote:
> From: Matthias Brugger <[email protected]>
>
> When trying to disable the block we bitwise or the control
> register with value zero. This will leave the block always turned on.
> Fix this by setting the corresponding bit to zero.
>
> Fixes: c83d45d5685f ("hwrng: iproc-rng200 - Add Broadcom IPROC RNG driver")
> Signed-off-by: Matthias Brugger <[email protected]>
Acked-by: Florian Fainelli <[email protected]>
--
Florian
On 14/12/2020 18:45, Scott Branden wrote:
>
>
> On 2020-12-14 8:04 a.m., [email protected] wrote:
>> From: Matthias Brugger <[email protected]>
>>
>> When trying to disable the block we bitwise or the control
>> register with value zero. This will leave the block always turned on.
>> Fix this by setting the corresponding bit to zero.
>>
>> Fixes: c83d45d5685f ("hwrng: iproc-rng200 - Add Broadcom IPROC RNG driver")
> Commit message needs to be re-written.
> I don't think this is an actual fix as the ~RNG_CTL_RNG_RBGEN_MASK already zeros the bit. This is just a code change, which is fine because it makes things clearer
Right, I'll reword it.
>> Signed-off-by: Matthias Brugger <[email protected]>
>> ---
>>
>> drivers/char/hw_random/iproc-rng200.c | 5 ++---
>> 1 file changed, 2 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/char/hw_random/iproc-rng200.c b/drivers/char/hw_random/iproc-rng200.c
>> index 01583faf9893..e106ce3c0146 100644
>> --- a/drivers/char/hw_random/iproc-rng200.c
>> +++ b/drivers/char/hw_random/iproc-rng200.c
>> @@ -28,7 +28,6 @@
>> #define RNG_CTRL_OFFSET 0x00
>> #define RNG_CTRL_RNG_RBGEN_MASK 0x00001FFF
>> #define RNG_CTRL_RNG_RBGEN_ENABLE 0x00000001
>> -#define RNG_CTRL_RNG_RBGEN_DISABLE 0x00000000
>>
>> #define RNG_SOFT_RESET_OFFSET 0x04
>> #define RNG_SOFT_RESET 0x00000001
>> @@ -61,7 +60,7 @@ static void iproc_rng200_restart(void __iomem *rng_base)
>> /* Disable RBG */
>> val = ioread32(rng_base + RNG_CTRL_OFFSET);
>> val &= ~RNG_CTRL_RNG_RBGEN_MASK;
> This mask will already zero the enable bit.
>> - val |= RNG_CTRL_RNG_RBGEN_DISABLE;
>> + val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
Correct, so no need for this extra line. I'll delete it.
>> iowrite32(val, rng_base + RNG_CTRL_OFFSET);
>>
>> /* Clear all interrupt status */
>> @@ -174,7 +173,7 @@ static void iproc_rng200_cleanup(struct hwrng *rng)
>> /* Disable RNG hardware */
>> val = ioread32(priv->base + RNG_CTRL_OFFSET);
>> val &= ~RNG_CTRL_RNG_RBGEN_MASK;
>> - val |= RNG_CTRL_RNG_RBGEN_DISABLE;
>> + val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
>> iowrite32(val, priv->base + RNG_CTRL_OFFSET);
>> }
>>
>