Re: [PATCH 1/2] hwrng: iproc-rng200: Fix disable of the block.

2020-12-18 Thread Matthias Brugger



On 14/12/2020 18:45, Scott Branden wrote:
> 
> 
> On 2020-12-14 8:04 a.m., matthias@kernel.org wrote:
>> From: Matthias Brugger 
>>
>> 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 
>> ---
>>
>>  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 0x1FFF
>>  #define RNG_CTRL_RNG_RBGEN_ENABLE   0x0001
>> -#define RNG_CTRL_RNG_RBGEN_DISABLE  0x
>>  
>>  #define RNG_SOFT_RESET_OFFSET   0x04
>>  #define RNG_SOFT_RESET  0x0001
>> @@ -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);
>>  }
>>  
> 



Re: [PATCH 1/2] hwrng: iproc-rng200: Fix disable of the block.

2020-12-14 Thread Scott Branden



On 2020-12-14 8:04 a.m., matthias@kernel.org wrote:
> From: Matthias Brugger 
>
> 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 
> ---
>
>  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  0x1FFF
>  #define RNG_CTRL_RNG_RBGEN_ENABLE0x0001
> -#define RNG_CTRL_RNG_RBGEN_DISABLE   0x
>  
>  #define RNG_SOFT_RESET_OFFSET0x04
>  #define RNG_SOFT_RESET   0x0001
> @@ -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);
>  }
>  



Re: [PATCH 1/2] hwrng: iproc-rng200: Fix disable of the block.

2020-12-14 Thread Florian Fainelli
On 12/14/20 8:04 AM, matthias@kernel.org wrote:
> From: Matthias Brugger 
> 
> 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 

Acked-by: Florian Fainelli 
-- 
Florian