[Intel-gfx] [PATCH 2/4] drm/i915/chv: Fix error path in GPU freq helpers

[David Weinehall]

On Fri, Jan 29, 2016 at 02:52:27PM +0200, Imre Deak wrote:
> Atm we wouldn't catch these errors or on the error path we would end up
> with a division-by-zero, fix this up.
> 
> Caught by Coverity.
> 
> Signed-off-by: Imre Deak <imre.deak at intel.com>

Reviewed-by: David Weinehall <david.weinehall at intel.com>

> ---
>  drivers/gpu/drm/i915/intel_pm.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 20bf854..740a0e3 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -7189,9 +7189,10 @@ static int chv_gpu_freq(struct drm_i915_private *dev_priv, int val)
>  {
>  	int div, czclk_freq = DIV_ROUND_CLOSEST(dev_priv->czclk_freq, 1000);
>  
> -	div = vlv_gpu_freq_div(czclk_freq) / 2;
> +	div = vlv_gpu_freq_div(czclk_freq);
>  	if (div < 0)
>  		return div;
> +	div /= 2;
>  
>  	return DIV_ROUND_CLOSEST(czclk_freq * val, 2 * div) / 2;
>  }
> @@ -7200,9 +7201,10 @@ static int chv_freq_opcode(struct drm_i915_private *dev_priv, int val)
>  {
>  	int mul, czclk_freq = DIV_ROUND_CLOSEST(dev_priv->czclk_freq, 1000);
>  
> -	mul = vlv_gpu_freq_div(czclk_freq) / 2;
> +	mul = vlv_gpu_freq_div(czclk_freq);
>  	if (mul < 0)
>  		return mul;
> +	mul /= 2;
>  
>  	/* CHV needs even values */
>  	return DIV_ROUND_CLOSEST(val * 2 * mul, czclk_freq) * 2;
> -- 
> 2.5.0
>