On Thu, May 02, 2013 at 10:48:08AM -0700, Jesse Barnes wrote:
> Both the docs and the existing code were wrong. So fix both and use a
> switch statement like we do elsewhere to make things simple & clear.
>
> Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
> ---
> drivers/gpu/drm/i915/intel_pm.c | 13 ++++++++++++-
> 1 file changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 0f4b46e..556b989 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -2902,7 +2902,18 @@ static void valleyview_enable_rps(struct drm_device *dev)
> GEN7_RC_CTL_TO_MODE);
>
> valleyview_punit_read(dev_priv, PUNIT_REG_GPU_FREQ_STS, &val);
> - dev_priv->mem_freq = 800 + (266 * (val >> 6) & 3);
> + switch ((val >> 6) & 3) {
> + case 0:
> + case 1:
> + dev_priv->mem_freq = 800;
> + break;
> + case 2:
> + dev_priv->mem_freq = 1066;
> + break;
> + case 3:
> + dev_priv->mem_freq = 1333;
> + break;
> + }
> DRM_DEBUG_DRIVER("DDR speed: %d MHz", dev_priv->mem_freq);
>
> DRM_DEBUG_DRIVER("GPLL enabled? %s\n", val & 0x10 ? "yes" : "no");
The code does what the author wants it to, but I don't have the doc that
says this:
Reviewed-by: Ben Widawsky <ben at bwidawsk.net>
Since I've set up a precedent of providing what I think are better
options:
freq_lut[] = {800, 800, 1066, 1333};
freq_lut[(val >> 6) & 3];
[really ugly one-liner redacted]
--
Ben Widawsky, Intel Open Source Technology Center
